1
|
Yoshina R, Hirano J, Nishimoto E, Sakamoto Y, Tajima K, Minabe S, Uyanik M, Ishihara K, Ikai T, Yashima E, Omine T, Ishiwari F, Saeki A, Kim J, Oh J, Kim D, Liu G, Yasuda T, Shinokubo H, Fukui N. Inner-Bond-Cleavage Approach to Figure-Eight Macrocycles from Planar Aromatic Hydrocarbons. J Am Chem Soc 2024. [PMID: 39315432 DOI: 10.1021/jacs.4c07985] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 09/25/2024]
Abstract
Figure-eight-shaped nonplanar π-systems adopt distinctive chiral D2-symmetric structures, which are ideal for realizing efficient circularly polarized luminescence (CPL). However, the short-step and enantioselective synthesis of figure-eight π-systems represents a considerable challenge for the conventional bottom-up synthetic strategy. Herein, we report that the oxidative cleavage of the internal double bond of a commercially available polycyclic aromatic hydrocarbon, i.e., dibenzo[g,p]chrysene (DBC), catalytically affords a figure-eight electron-accepting macrocycle, i.e., cyclobisbiphenylenecarbonyl (CBBC), with high scalability (up to 3.3 g) and excellent enantioselectivity (94% ee). This inner-bond-cleavage approach also applies to larger PAHs, affording highly distorted molecular frameworks that comprise two figure-eight subunits. Furthermore, we demonstrate that the peripheral functionalization of CBBC with carbazole afforded donor-acceptor-type emitter, which shows thermally activated delayed fluorescence and emits CPL with a g value of 1.0 × 10-2. This g value is ten times higher than those of previously reported chiral TADF-active emitters for circularly polarized organic light-emitting diodes. These results demonstrate that oxidative inner-bond cleavage is a powerful synthetic strategy for creating innovative materials that incorporate molecules with figure-eight structures.
Collapse
Affiliation(s)
- Reiji Yoshina
- Department of Molecular and Macromolecular Chemistry, Graduate School of Engineering, and Integrated Research Consortium on Chemical Science (IRCCS), Nagoya University, Furo-cho, Chikusa-ku, Nagoya, Aichi 464-8603, Japan
| | - Junichiro Hirano
- Department of Molecular and Macromolecular Chemistry, Graduate School of Engineering, and Integrated Research Consortium on Chemical Science (IRCCS), Nagoya University, Furo-cho, Chikusa-ku, Nagoya, Aichi 464-8603, Japan
| | - Emiko Nishimoto
- Department of Molecular and Macromolecular Chemistry, Graduate School of Engineering, and Integrated Research Consortium on Chemical Science (IRCCS), Nagoya University, Furo-cho, Chikusa-ku, Nagoya, Aichi 464-8603, Japan
| | - Yuki Sakamoto
- Department of Molecular and Macromolecular Chemistry, Graduate School of Engineering, and Integrated Research Consortium on Chemical Science (IRCCS), Nagoya University, Furo-cho, Chikusa-ku, Nagoya, Aichi 464-8603, Japan
| | - Keita Tajima
- Department of Molecular and Macromolecular Chemistry, Graduate School of Engineering, and Integrated Research Consortium on Chemical Science (IRCCS), Nagoya University, Furo-cho, Chikusa-ku, Nagoya, Aichi 464-8603, Japan
| | - Shunsuke Minabe
- Department of Molecular and Macromolecular Chemistry, Graduate School of Engineering, and Integrated Research Consortium on Chemical Science (IRCCS), Nagoya University, Furo-cho, Chikusa-ku, Nagoya, Aichi 464-8603, Japan
| | - Muhammet Uyanik
- Department of Molecular and Macromolecular Chemistry, Graduate School of Engineering, and Integrated Research Consortium on Chemical Science (IRCCS), Nagoya University, Furo-cho, Chikusa-ku, Nagoya, Aichi 464-8603, Japan
| | - Kazuaki Ishihara
- Department of Molecular and Macromolecular Chemistry, Graduate School of Engineering, and Integrated Research Consortium on Chemical Science (IRCCS), Nagoya University, Furo-cho, Chikusa-ku, Nagoya, Aichi 464-8603, Japan
| | - Tomoyuki Ikai
- Department of Molecular and Macromolecular Chemistry, Graduate School of Engineering, and Integrated Research Consortium on Chemical Science (IRCCS), Nagoya University, Furo-cho, Chikusa-ku, Nagoya, Aichi 464-8603, Japan
- PRESTO, Japan Science and Technology Agency (JST), Kawaguchi, Saitama 332-0012, Japan
| | - Eiji Yashima
- Department of Molecular and Macromolecular Chemistry, Graduate School of Engineering, and Integrated Research Consortium on Chemical Science (IRCCS), Nagoya University, Furo-cho, Chikusa-ku, Nagoya, Aichi 464-8603, Japan
| | - Takuya Omine
- Department of Applied Chemistry, Graduate School of Engineering, Osaka University, 2-1 Yamadaoka, Suita, Osaka 565-0871, Japan
| | - Fumitaka Ishiwari
- PRESTO, Japan Science and Technology Agency (JST), Kawaguchi, Saitama 332-0012, Japan
- Department of Applied Chemistry, Graduate School of Engineering, Osaka University, 2-1 Yamadaoka, Suita, Osaka 565-0871, Japan
| | - Akinori Saeki
- Department of Applied Chemistry, Graduate School of Engineering, Osaka University, 2-1 Yamadaoka, Suita, Osaka 565-0871, Japan
| | - Jinseok Kim
- Spectroscopy Laboratory for Functional π-Electronic Systems and Department of Chemistry, Yonsei University, Seoul 03722, Korea
| | - Juwon Oh
- Department of Chemistry, Soonchunhyang University, Asan, Chungnam 31538, Republic of Korea
| | - Dongho Kim
- Spectroscopy Laboratory for Functional π-Electronic Systems and Department of Chemistry, Yonsei University, Seoul 03722, Korea
| | - Guanting Liu
- Institute for Advanced Study, Kyushu University, 744 Motooka, Nishi-ku, Fukuoka 819-0395, Japan
| | - Takuma Yasuda
- Institute for Advanced Study, Kyushu University, 744 Motooka, Nishi-ku, Fukuoka 819-0395, Japan
| | - Hiroshi Shinokubo
- Department of Molecular and Macromolecular Chemistry, Graduate School of Engineering, and Integrated Research Consortium on Chemical Science (IRCCS), Nagoya University, Furo-cho, Chikusa-ku, Nagoya, Aichi 464-8603, Japan
| | - Norihito Fukui
- Department of Molecular and Macromolecular Chemistry, Graduate School of Engineering, and Integrated Research Consortium on Chemical Science (IRCCS), Nagoya University, Furo-cho, Chikusa-ku, Nagoya, Aichi 464-8603, Japan
- PRESTO, Japan Science and Technology Agency (JST), Kawaguchi, Saitama 332-0012, Japan
| |
Collapse
|
2
|
Kleinpeter E, Koch A. 1H and 13C NMR spectra of infinitene and the ring current effect of the aromatic molecule. MAGNETIC RESONANCE IN CHEMISTRY : MRC 2024; 62:686-693. [PMID: 38782584 DOI: 10.1002/mrc.5467] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/11/2024] [Revised: 05/08/2024] [Accepted: 05/08/2024] [Indexed: 05/25/2024]
Abstract
The spatial magnetic properties (through-space NMR shieldings-TSNMRSs-actually the ring current effect in 1H NMR spectroscopy) of the recently synthesized infinitene (the helically twisted [12]circulene) have been calculated using the GIAO perturbation method employing the nucleus-independent chemical shift (NICS) concept and visualized as iso-chemical-shielding surfaces (ICSS) of various size and direction. Both 1H and 13C chemical shifts of infinitene and the aromaticity of this esthetically very appealing molecule have been studied subject to the ring current effect thus obtained. This spatial magnetic response property of TSNMRSs dominates the different magnitude of 1H and 13C chemical shifts, especially in the cross-over section of infinitene, which is unequivocally classified as an aromatic molecule based on the deshielding belt of its ring current effect. Differences in aromaticity of infinitene compared with isolated benzene can also be qualified and quantified on the magnetic criterion.
Collapse
Affiliation(s)
- Erich Kleinpeter
- Institut für Chemie, Universität Potsdam, Potsdam (Golm), Germany
| | - Andreas Koch
- Institut für Chemie, Universität Potsdam, Potsdam (Golm), Germany
| |
Collapse
|
3
|
Valiulina LI, Cherepanov VN, Khoroshkin K. Insight into magnetically induced ring currents and photophysics of six-porphyrin nanorings. Phys Chem Chem Phys 2024; 26:22337-22345. [PMID: 39157944 DOI: 10.1039/d4cp02547d] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 08/20/2024]
Abstract
The series of nanorings based on Zn-porphyrins and tetraoxa-isophlorins in different oxidation states (Q = 0, 2+, 4+, 6+) have been studied studied computationally at density functional theory level (DFT) using BHandHLYP functional combined with def2-SVP basis sets. Magnetically induced ring currents of nanorings have been calculated using the GIMIC method and the Ampère-Maxwell integration scheme. Ring current calculations show that neutral nanorings sustain equal diatropic and paratropic currents of 8 nA T-1, resulting in zero net ring current strengths. The charged nanorings sustain strong ring currents with tropicity depending on the oxidation state Q. Among the considered nanorings, the nanoring composed of 6 isophlorins c-Iso66+ is the most aromatic with a ring current of IGIMIC = 81.6 nA T-1. The structure c-P62+ with a ring current of IGIMIC = 54.9 nA T-1 can be considered as the most aromatic among the synthesized porphyrin nanorings. Spin-orbit coupling matrix elements, oscillator strengths, and excitation energies calculated at the CAM-B3LYP/def2-SVP level of theory were used to estimate rate constants for radiative and nonradiative processes. The algorithm based on X-H approximation were used to calculate the internal conversion rates (kIC). The main channel for the deactivation of the excitation energy in the studied nanorings is the process of internal conversion. The deactivation of excited energy occurs due to the vibrations of certain groups of C-H bonds in the nanorings. The nanoring c-Iso6 has magnetically allowed low-lying transitions that contributes significantly to the paratropic ring current, resulting in strong local antiaromaticity in the tetraoxa-isophlorin units.
Collapse
Affiliation(s)
- Lenara I Valiulina
- Department of Optics and Spectroscopy, Tomsk State University, Tomsk, 634050, Russia.
| | - Victor N Cherepanov
- Department of Optics and Spectroscopy, Tomsk State University, Tomsk, 634050, Russia.
| | - Kirill Khoroshkin
- Department of Optics and Spectroscopy, Tomsk State University, Tomsk, 634050, Russia.
| |
Collapse
|
4
|
Hou L, Yang L, Yang G, Luo Z, Xiao W, Yang L, Wang F, Gong LZ, Liu X, Cao W, Feng X. Catalytic Asymmetric Dearomative [2 + 2] Photocycloaddition/Ring-Expansion Sequence of Indoles with Diversified Alkenes. J Am Chem Soc 2024; 146:23457-23466. [PMID: 38993029 DOI: 10.1021/jacs.4c06780] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 07/13/2024]
Abstract
Developing novel strategies for catalytic asymmetric dearomatization (CADA) reactions is highly valuable. Visible light-mediated photocatalysis is demonstrated to be a powerful tool to activate aromatic compounds for further synthetic transformations. Herein, a catalytic asymmetric dearomative [2 + 2] photocycloaddition/ring-expansion sequence of indoles with simple alkenes was reported, providing a facile access to enantioenriched cyclopenta[b]indoles with good to high yields and enantioselectivities by means of chiral lanthanide photocatalysis. This protocol exhibited a broad substrate scope and good functional group tolerance, as well as potential applications in the synthesis of bioactive molecules. Mechanistic studies, including control experiments, UV-vis absorption spectroscopy, emission spectroscopy, and DFT calculations, were carried out, shedding insights into the reaction mechanism and the origin of enantioselectivity.
Collapse
Affiliation(s)
- Liuzhen Hou
- Key Laboratory of Green Chemistry & Technology, Ministry of Education, College of Chemistry, Sichuan University, Chengdu 610064, China
| | - Longqing Yang
- Key Laboratory of Green Chemistry & Technology, Ministry of Education, College of Chemistry, Sichuan University, Chengdu 610064, China
| | - Gaofei Yang
- Key Laboratory of Green Chemistry & Technology, Ministry of Education, College of Chemistry, Sichuan University, Chengdu 610064, China
| | - Zhe Luo
- Key Laboratory of Green Chemistry & Technology, Ministry of Education, College of Chemistry, Sichuan University, Chengdu 610064, China
| | - Wanlong Xiao
- Key Laboratory of Green Chemistry & Technology, Ministry of Education, College of Chemistry, Sichuan University, Chengdu 610064, China
| | - Linhan Yang
- Center for Natural Products Research, Chengdu Institute of Biology, Chinese Academy of Sciences, Chengdu 610061, China
| | - Fei Wang
- Center for Natural Products Research, Chengdu Institute of Biology, Chinese Academy of Sciences, Chengdu 610061, China
| | - Liu-Zhu Gong
- Hefei National Research Center for Physical Sciences at the Microscale and Department of Chemistry, University of Science and Technology of China, Hefei, Anhui 230026, China
| | - Xiaohua Liu
- Key Laboratory of Green Chemistry & Technology, Ministry of Education, College of Chemistry, Sichuan University, Chengdu 610064, China
| | - Weidi Cao
- Key Laboratory of Green Chemistry & Technology, Ministry of Education, College of Chemistry, Sichuan University, Chengdu 610064, China
| | - Xiaoming Feng
- Key Laboratory of Green Chemistry & Technology, Ministry of Education, College of Chemistry, Sichuan University, Chengdu 610064, China
| |
Collapse
|
5
|
Arathi PK, Suresh CH. Direct Estimation of Aromatization Energy from 1H NMR and UV-Vis Absorption Data of Homodesmotic Molecules. J Org Chem 2024; 89:10485-10497. [PMID: 39042814 DOI: 10.1021/acs.joc.4c00668] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 07/25/2024]
Abstract
This study delves into the ring-opening reaction of two distinct diaryl-ring-pyran systems, referred to as drnp1 and drnp2, where the term 'ring' encompasses aromatic, nonaromatic, or antiaromatic motifs. These systems transform into the corresponding cis-ortho quinonoid systems, denoted as c-drnq1 and c-drnq2. Homodesmotic pairs (drnp1, drnp2) and (c-drnq1, c-drnq2) are categorized as (aromatic, nonaromatic), (aromatic, partially aromatic), (antiaromatic, nonaromatic), and (nonaromatic, nonaromatic), with their energy difference representing aromatization energy (Earoma). Using reliable density functional theory, Earoma is assessed for various aromatic and antiaromatic ring motifs, including borderline cases and nonaromatic structures. For example, benzene exhibits an Earoma of 23.4 kcal/mol, indicating 3.9 kcal/mol aromatic stabilization per CC bond, while cyclobutadiene shows -29.9 kcal/mol, indicating a 7.5 kcal/mol destabilization of the CC bond. This approach extends to evaluating global and local aromatic stabilization effects in polycyclic hydrocarbons, nonbenzenoid systems, and heterocyclic compounds. Additionally, variation in 1H NMR chemical shift (δavg) correlates with Earoma, suggesting that a -1.0 ppm shift corresponds to 24.2 kcal/mol aromatization energy. UV-vis absorption maxima difference (Δλavg) correlates linearly with Earoma, enabling direct assessment of aromatization energy from UV-vis spectra using suitable homodesmotic pairs. This comprehensive approach enhances our understanding of structural, energetic, and spectroscopic aspects of aromatic and antiaromatic systems.
Collapse
Affiliation(s)
- Puthiyavalappil K Arathi
- Chemical Sciences and Technology Division, CSIR-National Institute for Interdisciplinary Science and Technology, Thiruvananthapuram 695019, India
- Academy of Scientific and Innovative Research (AcSIR), Ghaziabad 201002, India
| | - Cherumuttathu H Suresh
- Chemical Sciences and Technology Division, CSIR-National Institute for Interdisciplinary Science and Technology, Thiruvananthapuram 695019, India
- Academy of Scientific and Innovative Research (AcSIR), Ghaziabad 201002, India
| |
Collapse
|
6
|
Song Z, Wang X, Feng W, Armand M, Zhou Z, Zhang H. Designer Anions for Better Rechargeable Lithium Batteries and Beyond. ADVANCED MATERIALS (DEERFIELD BEACH, FLA.) 2024; 36:e2310245. [PMID: 38839065 DOI: 10.1002/adma.202310245] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/03/2023] [Revised: 04/17/2024] [Indexed: 06/07/2024]
Abstract
Non-aqueous electrolytes, generally consisting of metal salts and solvating media, are indispensable elements for building rechargeable batteries. As the major sources of ionic charges, the intrinsic characters of salt anions are of particular importance in determining the fundamental properties of bulk electrolyte, as well as the features of the resulting electrode-electrolyte interphases/interfaces. To cope with the increasing demand for better rechargeable batteries requested by emerging application domains, the structural design and modifications of salt anions are highly desired. Here, salt anions for lithium and other monovalent (e.g., sodium and potassium) and multivalent (e.g., magnesium, calcium, zinc, and aluminum) rechargeable batteries are outlined. Fundamental considerations on the design of salt anions are provided, particularly involving specific requirements imposed by different cell chemistries. Historical evolution and possible synthetic methodologies for metal salts with representative salt anions are reviewed. Recent advances in tailoring the anionic structures for rechargeable batteries are scrutinized, and due attention is paid to the paradigm shift from liquid to solid electrolytes, from intercalation to conversion/alloying-type electrodes, from lithium to other kinds of rechargeable batteries. The remaining challenges and key research directions in the development of robust salt anions are also discussed.
Collapse
Affiliation(s)
- Ziyu Song
- Key Laboratory of Material Chemistry for Energy Conversion and Storage (Ministry of Education), School of Chemistry and Chemical Engineering, Huazhong University of Science and Technology, 1037 Luoyu Road, Wuhan, 430074, China
| | - Xingxing Wang
- Key Laboratory of Material Chemistry for Energy Conversion and Storage (Ministry of Education), School of Chemistry and Chemical Engineering, Huazhong University of Science and Technology, 1037 Luoyu Road, Wuhan, 430074, China
| | - Wenfang Feng
- Key Laboratory of Material Chemistry for Energy Conversion and Storage (Ministry of Education), School of Chemistry and Chemical Engineering, Huazhong University of Science and Technology, 1037 Luoyu Road, Wuhan, 430074, China
| | - Michel Armand
- Centre for Cooperative Research on Alternative Energies (CIC energiGUNE), Basque Research and Technology Alliance (BRTA), Alava Technology Park, Albert Einstein 48, Vitoria-Gasteiz, 01510, Spain
| | - Zhibin Zhou
- Key Laboratory of Material Chemistry for Energy Conversion and Storage (Ministry of Education), School of Chemistry and Chemical Engineering, Huazhong University of Science and Technology, 1037 Luoyu Road, Wuhan, 430074, China
| | - Heng Zhang
- Key Laboratory of Material Chemistry for Energy Conversion and Storage (Ministry of Education), School of Chemistry and Chemical Engineering, Huazhong University of Science and Technology, 1037 Luoyu Road, Wuhan, 430074, China
| |
Collapse
|
7
|
Ganoe B, Shee J. On the notion of strong correlation in electronic structure theory. Faraday Discuss 2024. [PMID: 39072670 DOI: 10.1039/d4fd00066h] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 07/30/2024]
Abstract
Strong correlation has been said to have many faces, and appears to have many synonyms of questionable suitability. In this work we aim not to define the term once and for all, but to highlight one possibility that is both rigorously defined and physically transparent, and remains so in reference to molecules and quantum lattice models. We survey both molecular examples - hydrogen systems (Hn, n = 2, 4, 6), Be2, H-He-H, and benzene - and the half-filled Hubbard model over a range of correlation regimes. Various quantities are examined including the extent of spin symmetry breaking in correlated single-reference wave functions, energetic ratios inspired by the Hubbard model and the Virial theorem, and metrics derived from the one- and two-electron reduced density matrices (RDMs). The trace and the square norm of the cumulant of the two-electron reduced density matrix capture what may well be defined as strong correlation. Accordingly, strong correlation is understood as a statistical dependence between two electrons, and is distinct from the concepts of "correlation energy" and more general than entanglement quantities that require a partitioning of a quantum system into distinguishable subspaces. This work enables us to build a bridge between a rigorous and quantifiable regime of strong electron correlation and more familiar chemical concepts such as anti-aromaticity in the context of Baird's rule.
Collapse
Affiliation(s)
- Brad Ganoe
- Department of Chemistry, Rice University, Houston, TX, 77005, USA.
| | - James Shee
- Department of Chemistry, Rice University, Houston, TX, 77005, USA.
| |
Collapse
|
8
|
Jiang Z, Kuninobu Y. Synthesis of a novel twisted π-conjugated macrocycle via double Friedel-Crafts reaction and its physical properties. Chem Commun (Camb) 2024; 60:7642-7645. [PMID: 38963239 DOI: 10.1039/d4cc00890a] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 07/05/2024]
Abstract
We synthesized a cyclic molecule from diarylalkynes and Meldrum's acid derivatives as the methylenation reagent via double Friedel-Crafts reaction. Single-crystal X-ray structure analysis confirmed the twisted structure of the molecule. We also investigated their physical properties and homoconjugation by UV-Vis, photoluminescence, DFT and TD-DFT calculations.
Collapse
Affiliation(s)
- Zhiyan Jiang
- Department of Interdisciplinary Engineering Sciences, Interdisciplinary Graduate School of Engineering Sciences, Kyushu University, 6-1 Kasugakoen, Kasuga-Shi, Fukuoka 816-8580, Japan
| | - Yoichiro Kuninobu
- Institute for Materials Chemistry and Engineering, Kyushu University, 6-1 Kasugakoen, Kasuga-Shi, Fukuoka 816-8580, Japan.
- Department of Interdisciplinary Engineering Sciences, Interdisciplinary Graduate School of Engineering Sciences, Kyushu University, 6-1 Kasugakoen, Kasuga-Shi, Fukuoka 816-8580, Japan
| |
Collapse
|
9
|
Borstelmann J, Schneider L, Rominger F, Deschler F, Kivala M. Helically Chiral π-Expanded Azocines Through Regioselective Beckmann Rearrangement and Their Charged States. Angew Chem Int Ed Engl 2024; 63:e202405570. [PMID: 38716767 DOI: 10.1002/anie.202405570] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/21/2024] [Indexed: 06/16/2024]
Abstract
We report a synthetic approach to π-expanded [6]helicenes incorporating tropone and azocine units in combination with a 5-membered ring, which exhibit intriguing structural, electronic, and chiroptical properties. The regioselective Beckmann rearrangement allows the isolation of helical scaffolds containing 8-membered lactam, azocine, and amine units. As shown by X-ray crystallographic analysis, the incorporation of tropone or azocine units leads to highly distorted [6]helicene moieties, with distinct packing motifs in the solid state. The compounds exhibit promising optoelectronic properties with considerable photoluminescence quantum yields and tunable emission wavelengths depending on the relative position of the nitrogen center within the polycyclic framework. Separation of the enantiomers by chiral high-performance liquid chromatography (HPLC) allowed characterization of their chiroptical properties by circular dichroism (CD) and circularly polarized luminescence (CPL) spectroscopy. The azocine compounds feature manifold redox chemistry, allowing for the characterization of the corresponding radical anions and cations as well as the dications and dianions, with near-infrared (NIR) absorption bands extending beyond 3000 nm. Detailed theoretical studies provided insights into the aromaticity evolution upon reduction and oxidation, suggesting that the steric strain prevents the azocine unit from undergoing aromatization, while the indene moiety dominates the observed redox chemistry.
Collapse
Affiliation(s)
- Jan Borstelmann
- Organisch-Chemisches Institut, Universität Heidelberg, Im Neuenheimer Feld 270, 69120, Heidelberg, Germany
| | - Lars Schneider
- Physikalisch-Chemisches Institut, Universität Heidelberg, Im Neuenheimer Feld 253, 69120, Heidelberg, Germany
| | - Frank Rominger
- Organisch-Chemisches Institut, Universität Heidelberg, Im Neuenheimer Feld 270, 69120, Heidelberg, Germany
| | - Felix Deschler
- Physikalisch-Chemisches Institut, Universität Heidelberg, Im Neuenheimer Feld 253, 69120, Heidelberg, Germany
| | - Milan Kivala
- Organisch-Chemisches Institut, Universität Heidelberg, Im Neuenheimer Feld 270, 69120, Heidelberg, Germany
| |
Collapse
|
10
|
Yang D, Cheung KM, Gong Q, Zhang L, Qiao L, Chen X, Huang Z, Miao Q. Synthesis, Structures and Properties of Trioxa[9]circulene and Diepoxycyclononatrinaphthalene. Angew Chem Int Ed Engl 2024; 63:e202402756. [PMID: 38563770 DOI: 10.1002/anie.202402756] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/07/2024] [Revised: 03/28/2024] [Accepted: 04/02/2024] [Indexed: 04/04/2024]
Abstract
This article presents trioxa[9]circulene (3) as a novel member of hetero[n]circulenes. Its synthesis began with the synthesis of dimethoxydioxa[8]helicene (5) and used dimethoxydiepoxycyclononatrinaphthalene (4) as a key intermediate, despite the condensation reaction predominantly yielding a 1,4-addition byproduct. The structures and properties of 3-5 were extensively investigated using experimental and computational methods. Analysis of the crystal structures reveal elongation of the internal C-C bonds in the nine-membered ring of 3 compared to 4 and 5. Computational studies demonstrate the remarkable flexibility of trioxa[9]circulene's saddle-shaped polycyclic framework, while the other two compounds are rigid with large racemization barriers. Optically pure forms of 4 and 5 exhibit absorption and luminescence dissymmetry factors on the order of 10-2, with smaller values observed for compound 4. In the crystal structures, molecules of 3 stack to form columns with remarkable π-π overlap, and the π-π interactions of 4 exhibit short intermolecular C-to-C contacts. Consequently, the solution-processed film of 4 functioned as a p-type organic semiconductor in field effect transistors.
Collapse
Affiliation(s)
- Daiyue Yang
- State Key Laboratory of Antiviral Drugs, Pingyuan Laboratory, School of Chemistry and Chemical Engineering, Henan Normal University, 453007, Xinxiang, Henan, China
- Shanghai-Hong Kong Joint Laboratory in Chemical Synthesis, Shanghai Institute of Organic Chemistry, Chinese Academy of Sciences, 230032, Shanghai, China
| | - Ka Man Cheung
- Department of Chemistry, The Chinese University of Hong Kong, Shatin, New Territories, Hong Kong, China
| | - Qi Gong
- Department of Chemistry, The Chinese University of Hong Kong, Shatin, New Territories, Hong Kong, China
| | - Li Zhang
- Department of Chemistry, The Chinese University of Hong Kong, Shatin, New Territories, Hong Kong, China
| | - Lulin Qiao
- State Key Laboratory of Antiviral Drugs, Pingyuan Laboratory, School of Chemistry and Chemical Engineering, Henan Normal University, 453007, Xinxiang, Henan, China
- Shanghai-Hong Kong Joint Laboratory in Chemical Synthesis, Shanghai Institute of Organic Chemistry, Chinese Academy of Sciences, 230032, Shanghai, China
| | - Xiao Chen
- Department of Chemistry, The Chinese University of Hong Kong, Shatin, New Territories, Hong Kong, China
| | - Zhifeng Huang
- Department of Chemistry, The Chinese University of Hong Kong, Shatin, New Territories, Hong Kong, China
| | - Qian Miao
- Department of Chemistry, The Chinese University of Hong Kong, Shatin, New Territories, Hong Kong, China
- Shanghai-Hong Kong Joint Laboratory in Chemical Synthesis, Shanghai Institute of Organic Chemistry, Chinese Academy of Sciences, 230032, Shanghai, China
| |
Collapse
|
11
|
Kenouche S, Bachir N, Bouchal W, Martínez-Araya JI. Aromaticity of six-membered nitro energetic compounds through molecular electrostatic potential, magnetic, electronic delocalization and reactivity-based indices. J Mol Graph Model 2024; 129:108728. [PMID: 38412811 DOI: 10.1016/j.jmgm.2024.108728] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/19/2023] [Revised: 02/06/2024] [Accepted: 02/13/2024] [Indexed: 02/29/2024]
Abstract
The electron density depletion associated with π-hole at the ring center typical of energetic compounds was clearly revealed by the molecular electrostatic potential (ESP). In addition, the spatial arrangement of NO2 groups appears to affect the ESP value in the ring center, and therefore sensitivity to detonation. Indeed, for monocyclic nitrobenzene compounds with the same number of NO2 groups, the ESP value in the ring center decreases as the NO2 groups are more closely spaced. As expected, the central rings become less aromatic as NO2 groups are added. The MCI, PDI, PLR, NICSzz(1), FLU indices are all strongly correlated with the ESP values observed in the ring center of the set of nitrobenzenes. Aromaticity indices based on electron delocalization criteria appear to be very sensitive to small variations in aromaticity. Among magnetic-based indices, only NICSzz(1) is capable to predict small changes in aromaticity. The PLR index derived from conceptual DFT is quite relevant for predicting small variations in aromaticity. According to our results, the most suitable aromaticity index is not based on a single criterion, and that selecting it is more subtle. Therefore, it is important to combine information from several criteria to obtain a more complete description of the aromaticity of the studied compounds.
Collapse
Affiliation(s)
- Samir Kenouche
- Group of Modeling of Chemical Systems using Quantum Calculations, Applied Chemistry Laboratory (LCA). University M. Khider of Biskra, 07000 Biskra, Algeria
| | - Nassima Bachir
- Group of Modeling of Chemical Systems using Quantum Calculations, Applied Chemistry Laboratory (LCA). University M. Khider of Biskra, 07000 Biskra, Algeria
| | - Wissam Bouchal
- Molecular Chemistry and Environment Laboratory, University of Mohammed Khider of Biskra, BP 145 RP, Biskra 07000, Algeria
| | - Jorge I Martínez-Araya
- Departamento de Ciencias Químicas, Facultad de Ciencias Exactas, Universidad Andres Bello (UNAB), Av. República 275, 8370146 Santiago, Chile; Centro de Química Teórica y Computacional (CQT&C). Facultad de Ciencias Exactas, Santiago, Chile.
| |
Collapse
|
12
|
Sarker M, Dobner C, Zahl P, Fiankor C, Zhang J, Saxena A, Aluru N, Enders A, Sinitskii A. Porous Nanographenes, Graphene Nanoribbons, and Nanoporous Graphene Selectively Synthesized from the Same Molecular Precursor. J Am Chem Soc 2024; 146:14453-14467. [PMID: 38747845 DOI: 10.1021/jacs.3c10842] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/30/2024]
Abstract
We demonstrate a family of molecular precursors based on 7,10-dibromo-triphenylenes that can selectively produce different varieties of atomically precise porous graphene nanomaterials through the use of different synthetic environments. Upon Yamamoto polymerization of these molecules in solution, the free rotations of the triphenylene units around the C-C bonds result in the formation of cyclotrimers in high yields. In contrast, in on-surface polymerization of the same molecules on Au(111) these rotations are impeded, and the coupling proceeds toward the formation of long polymer chains. These chains can then be converted to porous graphene nanoribbons (pGNRs) by annealing. Correspondingly, the solution-synthesized cyclotrimers can also be deposited onto Au(111) and converted into porous nanographenes (pNGs) via thermal treatment. Thus, both processes start with the same molecular precursor and end with a porous graphene nanomaterial on Au(111), but the type of product, pNG or pGNR, depends on the specific coupling approach. We also produced extended nanoporous graphenes (NPGs) through the lateral fusion of highly aligned pGNRs on Au(111) that were grown at high coverage. The pNGs can also be synthesized directly in solution by Scholl oxidative cyclodehydrogenation of cyclotrimers. We demonstrate the generality of this approach by synthesizing two varieties of 7,10-dibromo-triphenylenes that selectively produced six nanoporous products with different dimensionalities. The basic 7,10-dibromo-triphenylene monomer is amenable to structural modifications, potentially providing access to many new porous graphene nanomaterials. We show that by constructing different porous structures from the same building blocks, it is possible to tune the energy band gap in a wide range.
Collapse
Affiliation(s)
- Mamun Sarker
- Department of Chemistry, University of Nebraska - Lincoln, Lincoln, Nebraska 68588, United States
| | - Christoph Dobner
- Physikalisches Institut, Universität Bayreuth, Universitätsstraße 30, 95440 Bayreuth, Germany
| | - Percy Zahl
- Center for Functional Nanomaterials, Brookhaven National Laboratory, Upton, New York 11973, United States
| | - Christian Fiankor
- Department of Chemistry, University of Nebraska - Lincoln, Lincoln, Nebraska 68588, United States
| | - Jian Zhang
- Department of Chemistry, University of Nebraska - Lincoln, Lincoln, Nebraska 68588, United States
- The Molecular Foundry, Lawrence Berkeley National Laboratory, Berkeley, California 94720, United States
| | - Anshul Saxena
- Oden Institute for Computational Engineering and Sciences, The University of Texas at Austin, Austin, Texas 78712, United States
| | - Narayana Aluru
- Oden Institute for Computational Engineering and Sciences, The University of Texas at Austin, Austin, Texas 78712, United States
| | - Axel Enders
- Physikalisches Institut, Universität Bayreuth, Universitätsstraße 30, 95440 Bayreuth, Germany
| | - Alexander Sinitskii
- Department of Chemistry, University of Nebraska - Lincoln, Lincoln, Nebraska 68588, United States
- Nebraska Center for Materials and Nanoscience, University of Nebraska - Lincoln, Lincoln, Nebraska 68588, United States
| |
Collapse
|
13
|
Wang K, You X, Miao X, Yi Y, Peng S, Wu D, Chen X, Xu J, Sfeir MY, Xia J. Activated Singlet Fission Dictated by Anti-Kasha Property in a Rylene Imide Dye. J Am Chem Soc 2024; 146:13326-13335. [PMID: 38693621 DOI: 10.1021/jacs.4c01732] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/03/2024]
Abstract
A key challenge in the search of new materials capable of singlet fission (SF) arises from the primary energy conservation criterion, i.e., the energy of the triplet exciton has to be half that of the singlet (E(S1) ≥ 2E(T1)), which excludes most photostable organic materials from consideration and confines the design strategy to materials with low energy triplet states. One potential way to overcome this energy requirement and improve the triplet energy is to enable a SF channel from higher energy ("hot") excitonic states (Sn) in a process called activated SF. Herein, we demonstrate that efficient activated SF is achieved in a rylene imide-based derivative acenaphth[l, 2-a]acenaphthylene diimide (AADI). This process is enabled by an increase in the energy gap to greater than 1.0 eV between the S3 and S1 states due to the incorporation of an antiaromatic pentalene unit, which leads to the emergence of anti-Kasha properties in the isolated molecule. Transient spectroscopy studies show that AADI undergoes ultrafast SF from higher singlet excited states in thin film, with excitation wavelength-dependent SF yields. The SF yield of ∼200% is observed upon higher energy excitation, and long-lived free triplets persist on the μs time scale suggesting that AADI can be used in SF-enhanced devices. Our results suggest that enlarging the Sn-S1 energy gap is an effective way to turn on the activated SF channel and shed light on the development of novel, stable SF materials with high triplet energies.
Collapse
Affiliation(s)
- Kangwei Wang
- State Key Laboratory of Advanced Technology for Materials Synthesis and Processing, Center of Smart Materials and Devices, Wuhan University of Technology, Wuhan 430070, China
| | - Xiaoxiao You
- State Key Laboratory of Advanced Technology for Materials Synthesis and Processing, Center of Smart Materials and Devices, Wuhan University of Technology, Wuhan 430070, China
| | - Xiaodan Miao
- Beijing National Laboratory for Molecular Sciences, CAS Key Laboratory of Organic Solids, Institute of Chemistry, Chinese Academy of Sciences, Beijing 100190, China
- University of Chinese Academy Sciences, Beijing 100049, China
| | - Yuanping Yi
- Beijing National Laboratory for Molecular Sciences, CAS Key Laboratory of Organic Solids, Institute of Chemistry, Chinese Academy of Sciences, Beijing 100190, China
- University of Chinese Academy Sciences, Beijing 100049, China
| | - Shaoqian Peng
- State Key Laboratory of Advanced Technology for Materials Synthesis and Processing, Center of Smart Materials and Devices, Wuhan University of Technology, Wuhan 430070, China
| | - Di Wu
- State Key Laboratory of Advanced Technology for Materials Synthesis and Processing, Center of Smart Materials and Devices, Wuhan University of Technology, Wuhan 430070, China
- School of Chemistry, Chemical Engineering and Life Science, Wuhan University of Technology, Wuhan 430070, China
| | - Xingyu Chen
- State Key Laboratory of Advanced Technology for Materials Synthesis and Processing, Center of Smart Materials and Devices, Wuhan University of Technology, Wuhan 430070, China
- School of Chemistry, Chemical Engineering and Life Science, Wuhan University of Technology, Wuhan 430070, China
| | - Jingwen Xu
- State Key Laboratory of Advanced Technology for Materials Synthesis and Processing, Center of Smart Materials and Devices, Wuhan University of Technology, Wuhan 430070, China
- School of Chemistry, Chemical Engineering and Life Science, Wuhan University of Technology, Wuhan 430070, China
| | - Matthew Y Sfeir
- Photonics Initiative, Advanced Science Research Center, City University of New York, New York 10016, United States
- Department of Physics, Graduate Center, City University of New York, New York 10031, United States
| | - Jianlong Xia
- State Key Laboratory of Advanced Technology for Materials Synthesis and Processing, Center of Smart Materials and Devices, Wuhan University of Technology, Wuhan 430070, China
- School of Chemistry, Chemical Engineering and Life Science, Wuhan University of Technology, Wuhan 430070, China
- International School of Materials Science and Engineering, Wuhan University of Technology, Wuhan 430070, China
| |
Collapse
|
14
|
Chagas JCV, Milanez BD, Oliveira VP, Pinheiro M, Ferrão LFA, Aquino AJA, Lischka H, Machado FBC. A multi-descriptor analysis of substituent effects on the structure and aromaticity of benzene derivatives: π-Conjugation versus charge effects. J Comput Chem 2024; 45:863-877. [PMID: 38153839 DOI: 10.1002/jcc.27296] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/24/2023] [Revised: 11/29/2023] [Accepted: 12/10/2023] [Indexed: 12/30/2023]
Abstract
This work provides a detailed multi-component analysis of aromaticity in monosubstituted (X = CH3, CH 2 - , CH 2 + , NH2, NH-, NH+, OH, O-, and O+) and para-homodisubstituted (X = CH3, CH2, NH2, NH, OH, and O) benzene derivatives. We investigate the effects of substituents using single-reference (B3LYP/DFT) and multireference (CASSCF/MRCI) methods, focusing on structural (HOMA), vibrational (AI(vib)), topological (ELFπ), electronic (MCI), magnetic (NICS), and stability (S0-T1 splitting) properties. The findings reveal that appropriate π-electron-donating and π-electron-accepting substituents with suitable size and symmetry can interact with the π-system of the ring, significantly influencing π-electron delocalization. While the charge factor has a minimal impact on π-electron delocalization, the presence of a pz orbital capable of interacting with the π-electron delocalization is the primary factor leading to a deviation from the typical aromaticity characteristics observed in benzene.
Collapse
Affiliation(s)
- Julio C V Chagas
- Department of Chemistry, Aeronautics Institute of Technology, São José dos Campos, São Paulo, Brazil
| | - Bruno D Milanez
- Department of Chemistry, Aeronautics Institute of Technology, São José dos Campos, São Paulo, Brazil
| | - Vytor P Oliveira
- Department of Chemistry, Aeronautics Institute of Technology, São José dos Campos, São Paulo, Brazil
| | - Max Pinheiro
- Department of Chemistry, Aeronautics Institute of Technology, São José dos Campos, São Paulo, Brazil
| | - Luiz F A Ferrão
- Department of Chemistry, Aeronautics Institute of Technology, São José dos Campos, São Paulo, Brazil
| | - Adelia J A Aquino
- Department of Mechanical Engineering, Texas Tech University, Lubbock, Texas, USA
| | - Hans Lischka
- Department of Chemistry and Biochemistry, Texas Tech University, Lubbock, Texas, USA
| | - Francisco B C Machado
- Department of Chemistry, Aeronautics Institute of Technology, São José dos Campos, São Paulo, Brazil
| |
Collapse
|
15
|
Shukla P, Ambhore MD, Anand VG. Open shell (4 n + 2)π and closed shell 4 nπ planar core-modified decaphyrins. Chem Sci 2024; 15:6022-6027. [PMID: 38665541 PMCID: PMC11041311 DOI: 10.1039/d3sc05251f] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/04/2023] [Accepted: 03/09/2024] [Indexed: 04/28/2024] Open
Abstract
Planar 44π and 46π core-modified decaphyrins with ten thiophene units have been synthesized from short thiophene oligomers. They have been structurally characterized by single crystal X-ray diffraction with further support from spectroscopic analysis and quantum chemical calculations. Our analysis revealed diradicaloid characteristics for 46π species in contrast to the closed shell property of the 44π congener. Further, 44π and 46π undergo reversible two-electron chemical oxidation, as observed by spectro-electrochemical measurements.
Collapse
Affiliation(s)
- Pragati Shukla
- Department of Chemistry, Indian Institute of Science Education and Research (IISER) Pune 411008 Maharashtra India
| | - Madan D Ambhore
- Department of Chemistry, Indian Institute of Science Education and Research (IISER) Pune 411008 Maharashtra India
| | - Venkataramanarao G Anand
- Department of Chemistry, Indian Institute of Science Education and Research (IISER) Pune 411008 Maharashtra India
| |
Collapse
|
16
|
Wang K, Ito S, Ren S, Shimizu D, Fukui N, Kishi R, Liu Q, Osuka A, Song J, Shinokubo H. A Triply Linked Porphyrin-Norcorrole Hybrid with Singlet Diradical Character. Angew Chem Int Ed Engl 2024; 63:e202401233. [PMID: 38251909 DOI: 10.1002/anie.202401233] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/18/2024] [Revised: 01/22/2024] [Accepted: 01/22/2024] [Indexed: 01/23/2024]
Abstract
Norcorrole Ni(II) complexes have recently received considerable attention because they are readily accessible antiaromatic molecules. Their high stability under ambient conditions and ease of synthesis have enabled the exploration of the intrinsic properties of antiaromatic molecules. Here, we report the synthesis and properties of meso-meso singly linked porphyrin-norcorrole hybrids and a triply linked porphyrin-norcorrole hybrid. The singly linked and triply linked porphyrin-norcorrole hybrids were fully characterized, including an X-ray structural analysis. Due to their orthogonal conformation, the singly linked hybrids maintain the individual electronic properties of their porphyrin and norcorrole subunits, while the triply linked hybrid shows a significantly smaller electrochemical HOMO-LUMO gap (0.45 eV) than that of Ni(II) dimesitylnorcorrole (1.08 eV). Furthermore, the triply linked hybrid exhibits singlet diradical characteristics, as confirmed by VT NMR, ESR, and SQUID experiments.
Collapse
Affiliation(s)
- Kaisheng Wang
- Department of Molecular and Macromolecular Chemistry, Graduate School of Engineering, Nagoya University, Furo-cho, Chikusa-ku, Nagoya, Aichi, 464-8603, Japan
| | - Satoru Ito
- Department of Molecular and Macromolecular Chemistry, Graduate School of Engineering, Nagoya University, Furo-cho, Chikusa-ku, Nagoya, Aichi, 464-8603, Japan
| | - Shuang Ren
- College of Chemistry and Chemical Engineering, Advanced Catalytic Engineering Research Center of the Ministry of Education, Hunan University, Changsha, 410082, China
| | - Daiki Shimizu
- Department of Synthetic Chemistry and Biological Chemistry, Graduate School of Engineering, Kyoto University, Nishikyo-ku, Kyoto, 615-8510, Japan
| | - Norihito Fukui
- Department of Molecular and Macromolecular Chemistry, Graduate School of Engineering, Nagoya University, Furo-cho, Chikusa-ku, Nagoya, Aichi, 464-8603, Japan
- PRESTO, Japan Science and Technology Agency (JST), Kawaguchi, Saitama, 332-0012, Japan
| | - Ryohei Kishi
- Department of Materials Engineering Science, Graduate School of Engineering Science, Osaka University, 1-3 Machikaneyama, Toyonaka, Osaka, 560-8531, Japan
| | - Qiang Liu
- College of Chemistry and Chemical Engineering, Advanced Catalytic Engineering Research Center of the Ministry of Education, Hunan University, Changsha, 410082, China
| | - Atsuhiro Osuka
- Key Laboratory of Chemical Biology and Traditional Chinese Medicine, Ministry of Educational of China, Key Laboratory of the Assembly and Application of Organic Functional Molecules of Hunan Province, College of Chemistry and Chemical Engineering, Hunan Normal University, Changsha, 410081, China
| | - Jianxin Song
- Key Laboratory of Chemical Biology and Traditional Chinese Medicine, Ministry of Educational of China, Key Laboratory of the Assembly and Application of Organic Functional Molecules of Hunan Province, College of Chemistry and Chemical Engineering, Hunan Normal University, Changsha, 410081, China
| | - Hiroshi Shinokubo
- Department of Molecular and Macromolecular Chemistry, Graduate School of Engineering, Nagoya University, Furo-cho, Chikusa-ku, Nagoya, Aichi, 464-8603, Japan
| |
Collapse
|
17
|
Kino S, Ukai S, Fukui N, Haruki R, Kumai R, Wang Q, Horike S, Phung QM, Sundholm D, Shinokubo H. Close Stacking of Antiaromatic Ni(II) Norcorrole Originating from a Four-Electron Multicentered Bonding Interaction. J Am Chem Soc 2024; 146:9311-9317. [PMID: 38502926 PMCID: PMC10996016 DOI: 10.1021/jacs.4c01142] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/25/2024] [Revised: 03/04/2024] [Accepted: 03/05/2024] [Indexed: 03/21/2024]
Abstract
A π-conjugated molecule with one electronic spin often forms a π-stacked dimer through molecular orbital interactions between two unpaired electrons. The bonding is recognized as a multicentered two-electron interaction between the two π-conjugated molecules. Here, we disclose a multicentered bonding interaction between two antiaromatic molecules involving four electrons. We have synthesized an antiaromatic porphyrin analogue, Ni(II) bis(pentafluorophenyl)norcorrole. Its dimer adopts a face-to-face stacked structure with an extremely short stacking distance of 2.97 Å. The close stacking originates from a multicenter four-electron bonding interaction between the two molecules. The bonding electrons were experimentally observed via synchrotron X-ray diffraction analysis and corroborated by theoretical calculations. The intermolecular interaction of the molecular orbitals imparts the stacked dimer with aromatic character that is distinctly different from that of its monomer.
Collapse
Affiliation(s)
- Shota Kino
- Department
of Molecular and Macromolecular Chemistry, Graduate School of Engineering
and Integrated Research Consortium on Chemical Sciences (IRCCS), Nagoya University, Furo-cho, Chikusa-ku, Nagoya, Aichi 464-8603, Japan
| | - Shusaku Ukai
- Department
of Molecular and Macromolecular Chemistry, Graduate School of Engineering
and Integrated Research Consortium on Chemical Sciences (IRCCS), Nagoya University, Furo-cho, Chikusa-ku, Nagoya, Aichi 464-8603, Japan
| | - Norihito Fukui
- Department
of Molecular and Macromolecular Chemistry, Graduate School of Engineering
and Integrated Research Consortium on Chemical Sciences (IRCCS), Nagoya University, Furo-cho, Chikusa-ku, Nagoya, Aichi 464-8603, Japan
- PRESTO, Japan
Science and Technology Agency (JST), Kawaguchi, Saitama 332-0012, Japan
| | - Rie Haruki
- Photon
Factory, Institute of Materials Structure
Science, High Energy Accelerator Research Organization (KEK), Tsukuba, 305-0801, Japan
| | - Reiji Kumai
- Photon
Factory, Institute of Materials Structure
Science, High Energy Accelerator Research Organization (KEK), Tsukuba, 305-0801, Japan
| | - Qian Wang
- Department
of Chemistry, Faculty of Science, University
of Helsinki, Helsinki, FIN-00014, Finland
| | - Satoshi Horike
- Department
of Chemistry, Graduate School of Science, Kyoto University, Kitashirakawa Oiwake-cho, Sakyo-ku, Kyoto, 606-8502, Japan
| | - Quan Manh Phung
- Department
of Chemistry, Graduate School of Science, Nagoya University, Furo-cho,
Chikusa-ku, Nagoya, 464-8602, Japan
| | - Dage Sundholm
- Department
of Chemistry, Faculty of Science, University
of Helsinki, Helsinki, FIN-00014, Finland
| | - Hiroshi Shinokubo
- Department
of Molecular and Macromolecular Chemistry, Graduate School of Engineering
and Integrated Research Consortium on Chemical Sciences (IRCCS), Nagoya University, Furo-cho, Chikusa-ku, Nagoya, Aichi 464-8603, Japan
| |
Collapse
|
18
|
Yang C, Dong H, Li X, Zhou N, Liu Y, Jin J, Wang Y. The σ+π dual aromaticity of typical bi-tetrazole ring molecule TKX-50. Chemphyschem 2024; 25:e202400005. [PMID: 38259129 DOI: 10.1002/cphc.202400005] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/02/2024] [Revised: 01/19/2024] [Accepted: 01/23/2024] [Indexed: 01/24/2024]
Abstract
Two complexes of dihydroxylammonium 5,5'-bistetrazole-1,1'-diolate (TKX-50) were employed to evaluate the aromaticity of their tetrazole rings via deep analysis such as the electronic structure, the ZZ component of the natural chemical shielding tensor (NICSZZ) and component orbitals, localized orbital locator purely contributed by σ-orbitals (LOL-σ) and localized orbital locator purely contributed by π-orbitals (LOL-π), the anisotropy of the induced current density (AICD) and the ZZ component of iso-chemical shielding surface (ICSSZZ) of these tetrazole rings thereof. The conclusion shows: that all tetrazole rings and bi-tetrazole rings in complexes have strong σ and a comparable strength π double aromaticity; all these magnetic shields almost symmetrically increase from the central axis to the tetrazole ring atoms; tetrazole rings in complex II show a little stronger dual aromaticity than that in complex I mainly due to the different orientation of the fragment 2 encompassing two hydroxylamine groups resulting in different effects on the contributions of σ orbitals and π orbitals to total aromaticity of tetrazole rings thereof; the difference in aromaticity is fundamentally caused by the atoms O with stronger electron-withdrawing than atom N in fragment 2 interact with bi-tetrazole ring through O in complex I but through N in complex II.
Collapse
Affiliation(s)
- Chunhai Yang
- School of Materials Engineering, Changshu Institute of Technology, Suzhou, 215500, China
| | - Huilong Dong
- School of Materials Engineering, Changshu Institute of Technology, Suzhou, 215500, China
| | - Xue Li
- School of Petroleum Engineering, Changzhou University, Changzhou, 213164, China
| | - Ning Zhou
- School of Petroleum Engineering, Changzhou University, Changzhou, 213164, China
| | - Yi Liu
- College of Chemistry and Chemical Engineering, China University of Petroleum (East China), Qingdao, 266580, China
| | - Junxun Jin
- School of Materials Engineering, Changshu Institute of Technology, Suzhou, 215500, China
| | - Yinjun Wang
- BGRIMM Explosive & Blasting Technology Co., Ltd., Beijing, 100160, China
| |
Collapse
|
19
|
Hamamoto Y, Ochiai K, Li Y, Tapavicza E, Ito S. Synthesis and Properties of Azahomocorannulenyl Cations and Radicals. Angew Chem Int Ed Engl 2024; 63:e202319022. [PMID: 38153357 DOI: 10.1002/anie.202319022] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/11/2023] [Revised: 12/22/2023] [Accepted: 12/28/2023] [Indexed: 12/29/2023]
Abstract
Cycloheptatrienyl (tropyl) molecules are representative non-alternant hydrocarbons that offer interesting chemistry because of their unique structures and properties. However, there have been a limited number of polycyclic aromatic tropyl cations and radicals reported in the literature. Herein, we report the synthesis of a series of azahomocorannulene derivatives, where the key reactions are a 1,3-dipolar cycloaddition of polycyclic aromatic azomethine ylides with dibenzotropone and a subsequent palladium-catalyzed cyclization. X-ray diffraction analysis revealed that the obtained azahomocorannulenyl cation and radical adopt planar structures and exhibit unique packing structures. Their electronic and optical properties were investigated experimentally and theoretically to reveal their aromatic character.
Collapse
Affiliation(s)
- Yosuke Hamamoto
- School of Chemistry, Chemical Engineering and Biotechnology, Nanyang Technological University, 21 Nanyang Link, Singapore, 637371, Singapore
| | - Kotaro Ochiai
- School of Chemistry, Chemical Engineering and Biotechnology, Nanyang Technological University, 21 Nanyang Link, Singapore, 637371, Singapore
| | - Yongxin Li
- School of Chemistry, Chemical Engineering and Biotechnology, Nanyang Technological University, 21 Nanyang Link, Singapore, 637371, Singapore
| | - Enrico Tapavicza
- Department of Chemistry and Biochemistry, California State University, Long Beach, 1250 Bellflower Boulevard, Long Beach, CA 90840, USA
| | - Shingo Ito
- School of Chemistry, Chemical Engineering and Biotechnology, Nanyang Technological University, 21 Nanyang Link, Singapore, 637371, Singapore
| |
Collapse
|
20
|
Lim JM, Shim S, Bui HT, Kim J, Kim HJ, Hwa Y, Cho S. Substitution Effect of a Single Nitrogen Atom on π-Electronic Systems of Linear Polycyclic Aromatic Hydrocarbons (PAHs): Theoretically Visualized Coexistence of Mono- and Polycyclic π-Electron Delocalization. Molecules 2024; 29:784. [PMID: 38398536 PMCID: PMC10892997 DOI: 10.3390/molecules29040784] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/12/2024] [Revised: 01/31/2024] [Accepted: 02/05/2024] [Indexed: 02/25/2024] Open
Abstract
We theoretically investigated the nitrogen substitution effect on the molecular structure and π-electron delocalization in linear nitrogen-substituted polycyclic aromatic hydrocarbons (N-PAHs). Based on the optimized molecular structures and magnetic field-induced parameters of fused bi- and tricyclic linear N-PAHs, we found that the local π-electron delocalization of subcycles (e.g., mono- and bicyclic constituent moieties) in linear N-PAHs is preserved, despite deviation from ideal structures of parent monocycles. The introduction of a fused five-membered ring with a pyrrolic N atom (N-5MR) in linear N-PAHs significantly perturbs the π-electronic condition of the neighboring fused six-membered ring (6MR). Monocyclic pyrrole exhibits substantial bond length alternations, strongly influencing the π-electronic systems of both the fused N-5MR and 6MR in linear N-PAHs, depending on the location of shared covalent bonds. A fused six-membered ring with a graphitic N atom in an indolizine moiety cannot generate monocyclic π-electron delocalization but instead contributes to the formation of polycyclic π-electron delocalization. This is evidenced by bifurcated diatropic ring currents induced by an external magnetic field. In conclusion, the satisfaction of Hückel's 4n + 2 rule for both mono- and polycycles is crucial for understanding the overall π-electron delocalization. It is crucial to consider the unique characteristics of the three types of substituted N atoms and the spatial arrangement of 5MR and 6MR in N-PAHs.
Collapse
Affiliation(s)
- Jong Min Lim
- Department of Chemistry, Kyungpook National University, Daegu 41566, Republic of Korea;
| | - Sangdeok Shim
- Department of Chemistry, Sunchon National University, Suncheon 57922, Republic of Korea;
| | - Hoa Thi Bui
- Department of Chemistry, Chonnam National University, Gwangju 61186, Republic of Korea; (H.T.B.); (J.K.)
| | - Jimin Kim
- Department of Chemistry, Chonnam National University, Gwangju 61186, Republic of Korea; (H.T.B.); (J.K.)
| | - Ho-Joong Kim
- Department of Chemistry, Chosun University, Gwangju 61452, Republic of Korea;
| | - Yoon Hwa
- School of Electrical, Computer and Energy Engineering, Arizona State University, Tempe, AZ 85287, USA
| | - Sung Cho
- Department of Chemistry, Chonnam National University, Gwangju 61186, Republic of Korea; (H.T.B.); (J.K.)
| |
Collapse
|
21
|
Kuroda Y, Krell M, Kurokawa K, Takasu K. Synthesis of mesoionic triazolones via a formal [3+2] cycloaddition between 4-phenyl-1,2,4-triazoline-3,5-dione and alkynes. Chem Commun (Camb) 2024; 60:1719-1722. [PMID: 38240015 DOI: 10.1039/d3cc05088b] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/09/2024]
Abstract
1,2,4-Triazoline-3,5-diones (TADs) are versatile reagents and have found widespread adoption in chemical science. Despite their remarkable reactivity toward a wide array of unsaturated hydrocarbons, the chemical reaction between TADs and alkynes has remained largely unexplored. Herein, we demonstrate that 1,1,1,3,3,3-hexafluoro-2-propanol facilitates the unusual [3+2] cycloaddition between 4-phenyl-1,2,4-triazoline-3,5-dione and alkynes, resulting in the formation of unprecedented mesoionic triazolones. Moreover, the structural properties of the resulting triazolone have been investigated by employing X-ray diffraction analysis and Density Functional Theory (DFT) calculations.
Collapse
Affiliation(s)
- Yusuke Kuroda
- Graduate School of Pharmaceutical Sciences, Kyoto University Yoshida, Kyoto 606-8501, Japan.
- Research Foundation ITSUU Laboratory, Kawasaki, Kanagawa 213-0012, Japan
| | - Maya Krell
- Graduate School of Pharmaceutical Sciences, Kyoto University Yoshida, Kyoto 606-8501, Japan.
- Institute of Pharmaceutical Sciences, Department of Chemistry and Applied Biosciences, ETH Zurich, Zurich 8093, Switzerland
| | - Kazuma Kurokawa
- Graduate School of Pharmaceutical Sciences, Kyoto University Yoshida, Kyoto 606-8501, Japan.
| | - Kiyosei Takasu
- Graduate School of Pharmaceutical Sciences, Kyoto University Yoshida, Kyoto 606-8501, Japan.
| |
Collapse
|
22
|
Shil S, Bhattacharya D, Misra A, Bytautas L. Antiaromatic Molecules as Magnetic Couplers: A Computational Quest. J Phys Chem A 2024; 128:815-828. [PMID: 38267395 PMCID: PMC10860145 DOI: 10.1021/acs.jpca.3c05784] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/28/2023] [Revised: 12/28/2023] [Accepted: 01/03/2024] [Indexed: 01/26/2024]
Abstract
In this study, we investigate a set of organic diradical structures in which two oxo-verdazyl radicals are selected as radical spin centers that are connected (coupled) via six coupler molecules (CM), resulting in various magnetic (ferromagnetic (FM) or antiferromagnetic (AFM)) characteristics, as reflected by their exchange coupling constants (J). We have designed 12 diradicals with 6-antiaromatic couplers coupled with bis-oxo-verdazyl diradicals with meta-meta (m-m) and para-meta (p-m) positional connectivities. The nature of the magnetic coupling (ferromagnetic, nonmagnetic, or antiferromagnetic) and the magnitude of the exchange constant J depend on the type of coupler, the connecting point between each radical center and CM, the degree of aromaticity of the coupler, and the length of the through-bond distance between radical centers. The computed magnetic exchange coupling constants J for these diradicals at the B3LYP/6-311++G(d,p) and MN12SX/6-311++G(d,p) levels of theory are large for many of these structures, indicating strong ferromagnetic coupling (with positive J values). In some cases, magnetic couplings are observed with J > 1000 cm-1 (B3LYP/6-311++G(d,p)) and strong antiferromagnetic coupling (with negative J values) with J < -1000 cm-1 (B3LYP/6-311++G(d,p)). Similarly, in some cases, magnetic couplings are observed with J > 289 cm-1 (MN12SX/6-311++G(d,p)) and strong antiferromagnetic coupling (with negative J values) with J < -568 cm-1 (MN12SX/6-311++G(d,p)). Furthermore, while numerous studies have reported that the degree of aromaticity of molecular couplers often favors strong ferromagnetic coupling, displaying the high-spin character of diradicals in their ground states, the couplers chosen in this study are characterized as antiaromatic or nonaromatic. The current investigation provides evidence that, remarkably, antiaromatic couplers are able to enhance stability by favoring electronic diradical structures with very strong ferromagnetic coupling when the length of the through-bond distance and connectivity pattern between radical centers are selected in such a way that the FM coupling is optimized. The findings in this study offer new strategies in the design of novel organic materials with interesting magnetic properties for practical applications.
Collapse
Affiliation(s)
- Suranjan Shil
- Manipal
Centre for Natural Sciences (Centre of Excellence), Manipal Academy of Higher Education, Manipal 576104, India
| | | | - Anirban Misra
- Department
of Chemistry, University of North Bengal, Raja Rammohunpur, Siliguri 734013, India
| | - Laimutis Bytautas
- Department
of Chemistry, Galveston College, 4015 Avenue Q, Galveston, Texas 77550, United States
| |
Collapse
|
23
|
Bergner J, Borstelmann J, Cavinato LM, Fuenzalida-Werner JP, Walla C, Hinrichs H, Schulze P, Rominger F, Costa RD, Dreuw A, Kivala M. A Conformationally Stable π-Expanded X-Type Double Helicene Comprising Dihydropyracylene Units with Multistage Redox Behavior. Chemistry 2024; 30:e202303336. [PMID: 37986242 DOI: 10.1002/chem.202303336] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/12/2023] [Revised: 11/17/2023] [Accepted: 11/17/2023] [Indexed: 11/22/2023]
Abstract
A π-expanded X-type double [5]helicene comprising dihydropyracylene moieties was synthesized from commercially available acenaphthene. X-ray crystallographic analysis revealed the unique highly twisted structure of the compound resulting in the occurrence of two enantiomers which were separated by chiral HPLC, owing to their high conformational stability. The compound shows strongly bathochromically shifted UV/vis absorption and emission bands with small Stokes shift and considerable photoluminescence quantum yield and circular polarized luminescence response. The electrochemical studies revealed five facilitated reversible redox events, including three reductions and two oxidations, thus qualifying the compound as chiral multistage redox amphoter. The experimental findings are in line with the computational studies based on density functional theory pointing towards increased spatial extension of the frontier molecular orbitals over the polycyclic framework and a considerably narrowed HOMO-LUMO gap.
Collapse
Affiliation(s)
- John Bergner
- Organisch-Chemisches Institut, Universität Heidelberg, Im Neuenheimer Feld 270, 69120, Heidelberg, Germany
| | - Jan Borstelmann
- Organisch-Chemisches Institut, Universität Heidelberg, Im Neuenheimer Feld 270, 69120, Heidelberg, Germany
| | - Luca M Cavinato
- Technical University of Munich Campus Straubing, Chair of Biogenic Functional Materials, Schulgasse 22, 94315, Straubing, Germany
| | - Juan Pablo Fuenzalida-Werner
- Technical University of Munich Campus Straubing, Chair of Biogenic Functional Materials, Schulgasse 22, 94315, Straubing, Germany
| | - Christian Walla
- Organisch-Chemisches Institut, Universität Heidelberg, Im Neuenheimer Feld 270, 69120, Heidelberg, Germany
- Interdisziplinäres Zentrum für Wissenschaftliches Rechnen, Universität Heidelberg, Im Neuenheimer Feld 205, A, 69120, Heidelberg, Germany
| | - Heike Hinrichs
- Abteilung Chromatographie & Elektrophorese, Max-Planck-Institut für Kohlenforschung, Kaiser-Wilhelm-Platz 1, 45470, Mülheim an der Ruhr, Germany
| | - Philipp Schulze
- Abteilung Chromatographie & Elektrophorese, Max-Planck-Institut für Kohlenforschung, Kaiser-Wilhelm-Platz 1, 45470, Mülheim an der Ruhr, Germany
| | - Frank Rominger
- Organisch-Chemisches Institut, Universität Heidelberg, Im Neuenheimer Feld 270, 69120, Heidelberg, Germany
| | - Rubén D Costa
- Technical University of Munich Campus Straubing, Chair of Biogenic Functional Materials, Schulgasse 22, 94315, Straubing, Germany
| | - Andreas Dreuw
- Interdisziplinäres Zentrum für Wissenschaftliches Rechnen, Universität Heidelberg, Im Neuenheimer Feld 205, A, 69120, Heidelberg, Germany
| | - Milan Kivala
- Organisch-Chemisches Institut, Universität Heidelberg, Im Neuenheimer Feld 270, 69120, Heidelberg, Germany
| |
Collapse
|
24
|
Ruan L, Luo W, Zhang H, Liu P, Shi Y, An P. Cycl[2,2,4]azine-embedded non-alternant nanographenes containing fused antiaromatic azepine ring. Chem Sci 2024; 15:1511-1519. [PMID: 38274082 PMCID: PMC10806646 DOI: 10.1039/d3sc05515a] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/17/2023] [Accepted: 12/14/2023] [Indexed: 01/27/2024] Open
Abstract
The development of non-alternant nanographenes has attracted considerable attention due to their unique photophysical properties. Herein, we reported a novel aza-doped, non-alternant nanographene (NG) 1 by embedding the cycl[2,2,4]azine unit into the benzenoid NG framework. Single-crystal X-ray diffractometry suggests saddle or twisted nonplanar geometry of the entire backbone of 1 and coplanar conformation of the cycl[2,2,4]azine unit. DFT calculation together with solid structure indicates that NG 1 possesses significant local antiaromaticity in the azepine ring. By oxidative process or trifluoroacetic acid treatment, this nanographene can transform into a mono-radical cation, which was confirmed by UV/Vis absorption, 1H NMR, and electron paramagnetic resonance (EPR) spectroscopy. The antiaromaticity/aromaticity switching of the azepine ring on 1˙+ from 1 enables the high stability of this radical cation, which remained intact for over 1 day. Due to the electron-donating nature of the nitrogen and the unique electronic structure, NG 1 exhibits strong electron-donating properties, as proved by the intermolecular charge transfer towards C60 with a high association constant. Furthermore, selective modification of NG 1 was accomplished by Vilsmeier reaction, and the derivatives 7 and 8 with substituted benzophenone were obtained. The photophysical and electronic properties can be tuned by the introduction of different electronic groups in benzophenone.
Collapse
Affiliation(s)
- Lan Ruan
- School of Chemical Science and Technology, Yunnan University Kunming 650091 P. R. China
| | - Wanhua Luo
- School of Chemical Science and Technology, Yunnan University Kunming 650091 P. R. China
| | - Haifan Zhang
- School of Chemical Science and Technology, Yunnan University Kunming 650091 P. R. China
| | - Peng Liu
- School of Chemical Science and Technology, Yunnan University Kunming 650091 P. R. China
| | - Yong Shi
- School of Chemical Science and Technology, Yunnan University Kunming 650091 P. R. China
| | - Peng An
- School of Chemical Science and Technology, Yunnan University Kunming 650091 P. R. China
- Key Laboratory of Medicinal Chemistry for Natural Resource, Ministry of Education, Yunnan University Kunming 650091 P. R. China
| |
Collapse
|
25
|
Shen L, Gao X, Chang Z, Zhang C, Li Y, Lu J, Meng Q, Wu Q. Sufficient driving force for quinoidal isoindigo-based diradicaloids with tunable diradical characters. Phys Chem Chem Phys 2024; 26:2529-2538. [PMID: 38170813 DOI: 10.1039/d3cp05199d] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/05/2024]
Abstract
Stable organic π-conjugated diradcialoids with tunable diradical characters can profoundly affect emerging technology. Over the past years, great efforts have been devoted to studying the structure-diradical character relationship in diradicaloids. Herein, a series of quinoidal isoindigo (IID) compounds with different attached terminal end groups were designed. Detailed analysis focuses on elucidating the driving force for evoking and enhancing the diradical character in the quinoidal IID systems. The arylene units of the IID core and the bridged aromatic units determine the contribution of the open-shell diradical form in the ground state. Diradical character y0 correlates well with bond length alternation (BLA), the total HOMA, and the total NICS(1)zz, and it is tuned by bridged aromatic units and terminal end groups in symmetric systems. The zwitterionic character weakens the diradical character in asymmetric systems to different extents. This work contributes to the deep understanding of evoking and enhancing the diradical character in quinoidal IID-based diradcialoids, providing useful guidelines to produce new molecules with desirable properties.
Collapse
Affiliation(s)
- Li Shen
- College of Chemical Engineering and Environmental Chemistry, Weifang University, Weifang, 261061, China.
| | - Xiaobo Gao
- College of Chemical Engineering and Environmental Chemistry, Weifang University, Weifang, 261061, China.
| | - Zhanqing Chang
- College of Chemical Engineering and Environmental Chemistry, Weifang University, Weifang, 261061, China.
| | - Changhao Zhang
- College of Chemical Engineering and Environmental Chemistry, Weifang University, Weifang, 261061, China.
| | - Yue Li
- College of Chemical Engineering and Environmental Chemistry, Weifang University, Weifang, 261061, China.
| | - Jitao Lu
- College of Chemical Engineering and Environmental Chemistry, Weifang University, Weifang, 261061, China.
| | - Qingguo Meng
- College of Chemical Engineering and Environmental Chemistry, Weifang University, Weifang, 261061, China.
| | - Qian Wu
- College of Chemical Engineering and Environmental Chemistry, Weifang University, Weifang, 261061, China.
| |
Collapse
|
26
|
Hulley EB, Clennan EL. Dihydrophenanthrene Open-Shell Singlet Diradicals and Their Roles in the Mallory Photocyclization Reaction. J Am Chem Soc 2024; 146:1122-1131. [PMID: 38163932 DOI: 10.1021/jacs.3c12400] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/03/2024]
Abstract
A computational study (ωB97X-D/6-31G(d)) of the Mallory photocyclization reaction has revealed that the well-established dihydrophenanthrene (DHP) intermediates can adopt either closed-shell (CS) or open-shell-diradical (OS) singlet ground states. A detailed study of the properties of DHPs allowed their classifications as OS, borderline-OS, borderline-CS, or CS intermediates. The triplet electronic state and higher energy CS* isomer of all the OS singlet diradicals were computationally located, and the expected relationship between the diradical index, yo, and the triplet energy and the OS-CS* energy gaps was established. The importance of aromaticity in stabilizing the OS singlet diradicals was confirmed by using the Harmonic Oscillator Model of Aromaticity (HOMA). The thermal decompositions of DHPs by cycloreversions to regenerate the Mallory starting materials were also studied. The cycloreversion mechanism was described as a homolytic cleavage characterized by an anchimeric assistance continuum promoted by bis-β-homolytic cleavage.
Collapse
Affiliation(s)
- Elliott B Hulley
- Department of Chemistry, University of Wyoming, Laramie, Wyoming 82071, United States
| | - Edward L Clennan
- Department of Chemistry, University of Wyoming, Laramie, Wyoming 82071, United States
| |
Collapse
|
27
|
Dobrowolski JC, Ostrowski S. HOMA Index Establishes Similarity to a Reference Molecule. J Chem Inf Model 2023; 63:7744-7754. [PMID: 38055931 PMCID: PMC10751799 DOI: 10.1021/acs.jcim.3c01551] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/03/2023] [Revised: 11/24/2023] [Accepted: 11/27/2023] [Indexed: 12/08/2023]
Abstract
The article shows that the definition of the HOMA index of geometrical aromaticity satisfies the axioms of a similarity function between the examined and benzene ring. Consequently, for purely mathematical reasons, the index works exceptionally well as an index of aromaticity: it expresses a geometric similarity to the archetypal aromatic benzene. Thus, if the molecule is geometrically similar to benzene, then it is also chemically similar, and therefore, it is aromatic. However, the similarity property legitimizes using the HOMA-like indices to express similarity to molecules other than benzene, whether cyclic or linear and existing or hypothetical. The paper demonstrates an example of HOMA-similarity to cyclohexane, which expresses a (relaxed)-saturicity property not accompanied by strong structural strains or steric hindrances. Further, it is also shown that the HOMA index can evaluate the properties of whole molecules, such as 25 unbranched catacondensed isomers of hexacene. The index exhibits a significant quadratic correlation with the total energy differences of planar isomers from which the nonplanar ones deviate. Moreover, the HOMA index of hexacene isomers significantly correlates with the Kekulé count connected to the resonance energy in the Hückel approximation. As a result, the study shows that the HOMA index can be used not only for aromaticity analyses but also as a general chemical descriptor applicable to rings, chains, composed molecular moieties, or even whole molecules.
Collapse
Affiliation(s)
- Jan Cz. Dobrowolski
- Institute of Nuclear Chemistry
and Technology, 16 Dorodna Street, 03-195 Warsaw, Poland
| | - Sławomir Ostrowski
- Institute of Nuclear Chemistry
and Technology, 16 Dorodna Street, 03-195 Warsaw, Poland
| |
Collapse
|
28
|
Baranac-Stojanović M, Aleksić J, Stojanović M. Theoretical investigation of tautomerism of 2- and 4-pyridones: origin, substituent and solvent effects. Org Biomol Chem 2023; 22:144-158. [PMID: 38051113 DOI: 10.1039/d3ob01588b] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/07/2023]
Abstract
Computational investigation at the BHandHLYP/6-311+G(d,p) level of theory of the gas-phase tautomerism of 2- and 4-pyridones confirmed the slight prevalence of lactim in the case of the former, but its dominance in the case of the latter, as shown previously. Examination of aromaticity by using HOMA, EDDB, NBOdel, NICS and AICD led to the conclusion that tautomerization of 4-pyridone results in greater aromaticity gain. It is also driven by the Pauli repulsion relief, which was revealed by the tautomerization energy decomposition analysis. By contrast, in the case of 2-pyridone, lactim is favoured by orbital and electrostatic interactions and disfavoured by the Pauli repulsion. Aromaticity gain in this case is smaller. The position of the tautomeric equilibrium can be modulated by substituent inductive effects (Cl and F), inductive and resonance effects (NH2 and NO2), hydrogen bonding (NO2), and medium polarity, the increase of which increases lactam population.
Collapse
Affiliation(s)
- Marija Baranac-Stojanović
- University of Belgrade - Faculty of Chemistry, Studentski trg 12-16, P. O. Box 158, 11000 Belgrade, Serbia.
| | - Jovana Aleksić
- University of Belgrade - Institute of Chemistry, Technology and Metallurgy - Center for Chemistry, Njegoševa 12, P. O. Box 473, 11000 Belgrade, Serbia
| | - Milovan Stojanović
- University of Belgrade - Institute of Chemistry, Technology and Metallurgy - Center for Chemistry, Njegoševa 12, P. O. Box 473, 11000 Belgrade, Serbia
| |
Collapse
|
29
|
Stawski W, Zhu Y, Wei Z, Petrukhina MA, Anderson HL. Crystallographic evidence for global aromaticity in the di-anion and tetra-anion of a cyclophane hydrocarbon. Chem Sci 2023; 14:14109-14114. [PMID: 38098717 PMCID: PMC10718070 DOI: 10.1039/d3sc04251k] [Citation(s) in RCA: 5] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/14/2023] [Accepted: 09/20/2023] [Indexed: 12/17/2023] Open
Abstract
[24]Paracyclophanetetraene is a classic example of a macrocyclic hydrocarbon that becomes globally aromatic on reduction to the di-anion, and switches to globally anti-aromatic in the tetra-anion. This redox activity makes it promising as an electrode material for batteries. Here, we report the solid-state structures of the di- and tetra-anions of this cyclophane, in several coordination environments. The changes in bond length on reduction yield insights into the global aromaticity of the di-anion (26π electrons), and anti-aromaticity of the tetra-anion (28π electrons), that were previously deduced from NMR spectra of species generated in situ. The experimental geometries of the aromatic di-anion and anti-aromatic tetra-anion from X-ray crystallographic data match well with gas-phase calculated structures, and reproduce the low symmetry expected in the anti-aromatic ring. Comparison of coordinated and naked anions confirms that metal coordination has little effect on the bond lengths. The UV-vis-NIR absorption spectra show a sharp intense peak at 878 nm for the di-anion, whereas the tetra-anion gives a broad spectrum typical of an anti-aromatic system.
Collapse
Affiliation(s)
- Wojciech Stawski
- Department of Chemistry, University at Albany, State University of New York Albany NY 12222 USA
- Department of Chemistry, University of Oxford, Chemistry Research Laboratory Oxford OX1 3TA UK
| | - Yikun Zhu
- Department of Chemistry, University at Albany, State University of New York Albany NY 12222 USA
| | - Zheng Wei
- Department of Chemistry, University at Albany, State University of New York Albany NY 12222 USA
| | - Marina A Petrukhina
- Department of Chemistry, University at Albany, State University of New York Albany NY 12222 USA
| | - Harry L Anderson
- Department of Chemistry, University of Oxford, Chemistry Research Laboratory Oxford OX1 3TA UK
| |
Collapse
|
30
|
Nad P, Mukherjee A. A Lewis Acid-Base Pair Catalyzed Dearomative Transformation of Unprotected Indoles via B-H Bond Activation. Chem Asian J 2023; 18:e202300714. [PMID: 37811913 DOI: 10.1002/asia.202300714] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/14/2023] [Revised: 09/29/2023] [Accepted: 10/09/2023] [Indexed: 10/10/2023]
Abstract
A sustainable and metal-free protocol has been described for the reduction of unprotected indoles. The catalytic system consists of B(C6 F5 )3 and THF as a Lewis acid-base pair that can activate the B-H bond of pincolborane (HBpin). The catalytic system encompasses a broad substrate scope. Control experiments were conducted to understand the possible catalytic intermediates involved during the present protocol.
Collapse
Affiliation(s)
- Pinaki Nad
- Department of Chemistry, Indian Institute of Technology Bhilai GEC Campus, Sejbahar, Raipur, 492015, Chhattisgarh (India
| | - Arup Mukherjee
- Department of Chemistry, Indian Institute of Technology Bhilai GEC Campus, Sejbahar, Raipur, 492015, Chhattisgarh (India
| |
Collapse
|
31
|
Cao N, Björk J, Corral-Rascon E, Chen Z, Ruben M, Senge MO, Barth JV, Riss A. The role of aromaticity in the cyclization and polymerization of alkyne-substituted porphyrins on Au(111). Nat Chem 2023; 15:1765-1772. [PMID: 37723257 DOI: 10.1038/s41557-023-01327-6] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/18/2022] [Accepted: 08/17/2023] [Indexed: 09/20/2023]
Abstract
Aromaticity is an established and widely used concept for the prediction of the reactivity of organic molecules. However, its role remains largely unexplored in on-surface chemistry, where the interaction with the substrate can alter the electronic and geometric structure of the adsorbates. Here we investigate how aromaticity affects the reactivity of alkyne-substituted porphyrin molecules in cyclization and coupling reactions on a Au(111) surface. We examine and quantify the regioselectivity in the reactions by scanning tunnelling microscopy and bond-resolved atomic force microscopy at the single-molecule level. Our experiments show a substantially lower reactivity of carbon atoms that are stabilized by the aromatic diaza[18]annulene pathway of free-base porphyrins. The results are corroborated by density functional theory calculations, which show a direct correlation between aromaticity and thermodynamic stability of the reaction products. These insights are helpful to understand, and in turn design, reactions with aromatic species in on-surface chemistry and heterogeneous catalysis.
Collapse
Affiliation(s)
- Nan Cao
- Physics Department E20, Technical University of Munich, Garching, Germany
| | - Jonas Björk
- Department of Physics, Chemistry and Biology, IFM, Linköping University, Linköping, Sweden
| | | | - Zhi Chen
- Institute of Nanotechnology, Karlsruhe Institute of Technology, Eggenstein-Leopoldshafen, Germany
- College of Chemistry and Environmental Engineering, Shenzhen University, Shenzhen, PR China
| | - Mario Ruben
- Institute of Nanotechnology, Karlsruhe Institute of Technology, Eggenstein-Leopoldshafen, Germany
- Centre Européen de Science Quantique, Institut de Science et d'Ingénierie Supramoléculaires (UMR 7006), CNRS-Université de Strasbourg, Strasbourg, France
- Institute of Quantum Materials and Technologies, Karlsruhe Institute of Technology, Eggenstein-Leopoldshafen, Germany
| | - Mathias O Senge
- Institute for Advanced Study (TUM-IAS), Focus Group-Molecular and Interfacial Engineering of Organic Nanosystems, Technical University of Munich, Garching, Germany
| | - Johannes V Barth
- Physics Department E20, Technical University of Munich, Garching, Germany.
| | - Alexander Riss
- Physics Department E20, Technical University of Munich, Garching, Germany.
| |
Collapse
|
32
|
Zhao M, Chen S, He C, Zhou Y. Synthesis, Structure, and Properties of a Nitrogen-Boron-Nitrogen-Embedded Polycyclic π-System Containing a Pleiaheptalene Framework. Org Lett 2023. [PMID: 38015797 DOI: 10.1021/acs.orglett.3c03311] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2023]
Abstract
A novel polycyclic π-system (1) featuring both a pleiaheptalene framework (a three-fused heptagon system) and nitrogen-boron-nitrogen (NBN) unit was constructed by electrophilic borylation. A combined experimental and computational study demonstrated that 1 has a highly twisted π-backbone with approximate C2 symmetry, which can undergo conformational isomerization at room temperature in contrast to pleiaheptalene. It was also found that 1 can bind the fluoride ion in the solution, which induces changes in the absorption and emission spectra.
Collapse
Affiliation(s)
- Mengna Zhao
- College of Life Science, China Jiliang University, Hangzhou, Zhejiang 310018, China
| | - Shuaishuai Chen
- College of Life Science, China Jiliang University, Hangzhou, Zhejiang 310018, China
| | - Chun He
- Apeloa Pharmaceutical Co., Ltd., Dongyang, Zhejiang 322118, China
| | - Yifeng Zhou
- College of Life Science, China Jiliang University, Hangzhou, Zhejiang 310018, China
| |
Collapse
|
33
|
Ferrão LFA, Pontes MAP, Fernandes GFS, Bettanin F, Aquino AJA, Lischka H, Nachtigallova D, Machado FBC. Stability and Reactivity of the Phenalene and Olympicene Isomers. J Phys Chem A 2023; 127:9430-9441. [PMID: 37920974 DOI: 10.1021/acs.jpca.3c04331] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/04/2023]
Abstract
The phenalene (triangulene) and olympicene molecules belong to the polycyclic aromatic hydrocarbon class, which have attracted substantial technological interest due to their unique electronic properties. Electronic structure calculations serve as a valuable tool in investigating the stability and reactivity of these molecular systems. In the present work, the multireference calculations, namely, the complete active space second-order perturbation theory and multireference averaged quadratic coupled cluster (MR-AQCC), were employed to study the reactivity and stability of phenalene and olympicene isomers, as well as their modified structures where the sp3-carbon at the borders were removed. The harmonic oscillator model of aromaticity (HOMA) and the nucleus-independent chemical shift as geometric and magnetic indexes calculated with density functional theory were utilized to assess the aromaticity of the studied molecules. These indexes were compared with properties such as the excitation energy and natural orbitals occupation. The reactivity analyzed using the HOMA index combined with MR-AQCC revealed the radical character of certain structures as well as the weakening of their aromaticity. Moreover, the results suggest that the removal of sp3-carbon atoms and the addition of hydrogen atoms did not alter the π network and the excitation energies of the phenalene molecules.
Collapse
Affiliation(s)
- Luiz F A Ferrão
- Departamento de Química, Instituto Tecnológico de Aeronáutica, São José dos Campos 122228-900, SP, Brazil
| | - Marcelo A P Pontes
- Departamento de Química, Instituto Tecnológico de Aeronáutica, São José dos Campos 122228-900, SP, Brazil
| | - Gabriel F S Fernandes
- Departamento de Química, Instituto Tecnológico de Aeronáutica, São José dos Campos 122228-900, SP, Brazil
| | - Fernanda Bettanin
- Escola de Artes, Ciências e Humanidades (EACH) - Universidade de São Paulo (USP), São Paulo 03828-000, SP, Brazil
| | - Adélia J A Aquino
- Department of Mechanical Engineering, Texas Tech University, Lubbock, Texas 79409, United States
| | - Hans Lischka
- Department of Chemistry and Biochemistry, Texas Tech University, Lubbock, Texas 79409-1061, United States
| | - Dana Nachtigallova
- Institute of Organic Chemistry and Biochemistry, Academy of Sciences of the Czech Republic, Flemingovo nam. 2, CZ-16610 Prague 6, Czech Republic
- IT4Innovations, VŠB-Technical University of Ostrava, 17. listopadu 2172/15, 70800 Ostrava-Poruba, Czech Republic
| | - Francisco B C Machado
- Departamento de Química, Instituto Tecnológico de Aeronáutica, São José dos Campos 122228-900, SP, Brazil
| |
Collapse
|
34
|
Zhong Q, Mardyukov A, Solel E, Ebeling D, Schirmeisen A, Schreiner PR. On-Surface Synthesis and Real-Space Visualization of Aromatic P 3 N 3. Angew Chem Int Ed Engl 2023; 62:e202310121. [PMID: 37702299 DOI: 10.1002/anie.202310121] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/16/2023] [Revised: 09/11/2023] [Accepted: 09/12/2023] [Indexed: 09/14/2023]
Abstract
On-surface synthesis is at the verge of emerging as the method of choice for the generation and visualization of unstable or unconventional molecules, which could not be obtained via traditional synthetic methods. A case in point is the on-surface synthesis of the structurally elusive cyclotriphosphazene (P3 N3 ), an inorganic aromatic analogue of benzene. Here, we report the preparation of this fleetingly existing species on Cu(111) and Au(111) surfaces at 5.2 K through molecular manipulation with unprecedented precision, i.e., voltage pulse-induced sextuple dechlorination of an ultra-small (about 6 Å) hexachlorophosphazene P3 N3 Cl6 precursor by the tip of a scanning probe microscope. Real-space atomic-level imaging of cyclotriphosphazene reveals its planar D3h -symmetric ring structure. Furthermore, this demasking strategy has been expanded to generate cyclotriphosphazene from a hexaazide precursor P3 N21 via a different stimulation method (photolysis) for complementary measurements by matrix isolation infrared and ultraviolet spectroscopy.
Collapse
Affiliation(s)
- Qigang Zhong
- Institute of Applied Physics, Justus Liebig University Giessen, Giessen, Germany
- Center for Materials Research (ZfM), Justus Liebig University Giessen, Giessen, Germany
| | - Artur Mardyukov
- Center for Materials Research (ZfM), Justus Liebig University Giessen, Giessen, Germany
- Institute of Organic Chemistry, Justus Liebig University Giessen, Giessen, Germany
| | - Ephrath Solel
- Center for Materials Research (ZfM), Justus Liebig University Giessen, Giessen, Germany
- Institute of Organic Chemistry, Justus Liebig University Giessen, Giessen, Germany
| | - Daniel Ebeling
- Institute of Applied Physics, Justus Liebig University Giessen, Giessen, Germany
- Center for Materials Research (ZfM), Justus Liebig University Giessen, Giessen, Germany
| | - André Schirmeisen
- Institute of Applied Physics, Justus Liebig University Giessen, Giessen, Germany
- Center for Materials Research (ZfM), Justus Liebig University Giessen, Giessen, Germany
| | - Peter R Schreiner
- Center for Materials Research (ZfM), Justus Liebig University Giessen, Giessen, Germany
- Institute of Organic Chemistry, Justus Liebig University Giessen, Giessen, Germany
| |
Collapse
|
35
|
Borstelmann J, Bergner J, Rominger F, Kivala M. A Negatively Curved π-Expanded Pyracylene Comprising a Tropylium Cation. Angew Chem Int Ed Engl 2023; 62:e202312740. [PMID: 37739928 DOI: 10.1002/anie.202312740] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/29/2023] [Revised: 09/22/2023] [Accepted: 09/22/2023] [Indexed: 09/24/2023]
Abstract
We disclose π-expanded pyracylenes and their cationic species comprising 7-membered rings. The compounds were synthesized by stepwise oxidative cyclodehydrogenation to monitor the effect of successive cyclization on the structural and optoelectronic properties. As shown by X-ray crystallography, the complete cyclization leads to a boat-shaped scaffold featuring negative curvature provided by the 7-membered ring. The embedded tropone unit enabled the convenient generation of a stabilized tropylium cation, showing bathochromically shifted absorption bands reaching into the near-infrared region beyond 1000 nm. The altered structural features, supported by theoretical calculations, point towards the positively charged 7-membered ring having aromatic character.
Collapse
Affiliation(s)
- Jan Borstelmann
- Organisch-Chemisches Institut, Universität Heidelberg, Im Neuenheimer Feld 270, 69120, Heidelberg, Germany
| | - John Bergner
- Organisch-Chemisches Institut, Universität Heidelberg, Im Neuenheimer Feld 270, 69120, Heidelberg, Germany
| | - Frank Rominger
- Organisch-Chemisches Institut, Universität Heidelberg, Im Neuenheimer Feld 270, 69120, Heidelberg, Germany
| | - Milan Kivala
- Organisch-Chemisches Institut, Universität Heidelberg, Im Neuenheimer Feld 270, 69120, Heidelberg, Germany
| |
Collapse
|
36
|
Tang J, Zhang S, Zhou BW, Wang W, Zhao L. Hyperconjugative Aromaticity-Based Circularly Polarized Luminescence Enhancement in Polyaurated Heterocycles. J Am Chem Soc 2023; 145:23442-23451. [PMID: 37870916 DOI: 10.1021/jacs.3c04953] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/24/2023]
Abstract
Hyperconjugative aromaticity (HA) frequently appears in metalla-aromatics, but its effect on photophysical properties remains unexplored to date. Herein, we reveal two different HA scenarios in nearly isostructural triaurated indolium and benzofuranylium compounds. The biased HAs show a discernible effect on the spatial arrangement of metal atoms and thus tailor metal parentage in frontier orbitals and the HOMO-LUMO energy gap. Theoretical calculations and structural analyses demonstrate that HA not only influences the degree of electron delocalization over the trimetalated aromatic rings but also affects π-coordination of Au(I) and intercluster aurophilic interaction. Consequently, the triaurated benzofuranylium complex shows better photoluminescence performance (quantum yield up to 49.7%) over the indolium analogue. Furthermore, four pairs of axially chiral bibenzofuran-centered trinuclear and hexanuclear gold clusters were purposefully synthesized to correlate their HA-involved structures with the chiroptical response. The triaurated benzofuranylium complexes exhibit strong circular dichroism (CD) response in solution but CPL silence even in solid film. In contrast, the hexa-aurated homologues display strong CD and intense CPL signals in both aggregated state and solid film (luminescence anisotropy factor glum up to 10-3). Their amplified chiroptical response is finally ascribed to the dominant intermolecular exciton couplings of large assemblies formed through the HA-tailored aggregation of hexanuclear compounds.
Collapse
Affiliation(s)
- Jian Tang
- Key Laboratory of Bioorganic Phosphorus Chemistry & Chemical Biology (Ministry of Education), Department of Chemistry, Tsinghua University, Beijing 100084, China
- Sinopec (Beijing) Research Institute of Chemical Industry, Beijing 100013, China
| | - Siqi Zhang
- Key Laboratory of Bioorganic Phosphorus Chemistry & Chemical Biology (Ministry of Education), Department of Chemistry, Tsinghua University, Beijing 100084, China
- Jiangsu Key Laboratory of New Drug Research and Clinical Pharmacy, Xuzhou Medical University, Xuzhou, Jiangsu 221004, China
| | - Bo-Wei Zhou
- Key Laboratory of Bioorganic Phosphorus Chemistry & Chemical Biology (Ministry of Education), Department of Chemistry, Tsinghua University, Beijing 100084, China
| | - Wan Wang
- Key Laboratory of Bioorganic Phosphorus Chemistry & Chemical Biology (Ministry of Education), Department of Chemistry, Tsinghua University, Beijing 100084, China
| | - Liang Zhao
- Key Laboratory of Bioorganic Phosphorus Chemistry & Chemical Biology (Ministry of Education), Department of Chemistry, Tsinghua University, Beijing 100084, China
| |
Collapse
|
37
|
Foroutan-Nejad C. Magnetic Antiaromaticity─Paratropicity─Does Not Necessarily Imply Instability. J Org Chem 2023; 88:14831-14835. [PMID: 37774173 PMCID: PMC10594649 DOI: 10.1021/acs.joc.3c01807] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/10/2023] [Indexed: 10/01/2023]
Abstract
Magnetically induced ring currents are a conventional tool for the characterization of aromaticity. Dia- and paratropic currents are thought to be associated with stabilization (aromaticity) and destabilization (antiaromaticity), respectively. In the present work, I have questioned the validity of the paratropic currents as a measure of antiaromaticity among monocyclic hydrocarbons. I have shown that while reduced/oxidized radical ions of hydrocarbons sustain strong paratropic currents, they often gain extra stabilization via cyclic conjugation compared to their acyclic counterparts.
Collapse
Affiliation(s)
- Cina Foroutan-Nejad
- Institute of Organic Chemistry, Polish Academy of Sciences, Kasprzaka 44/52, 01-224 Warsaw, Poland
| |
Collapse
|
38
|
Sudhakaran KP, Benny A, John AT, Hariharan M. Exploring the influence of graphene on antiaromaticity of pentalene. Phys Chem Chem Phys 2023; 25:26986-26990. [PMID: 37812393 DOI: 10.1039/d3cp02760k] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/10/2023]
Abstract
Theoretical investigations on the influence of graphene fragments on the antiaromaticity of pentalene are conducted by employing multiple aromaticity descriptors based on magnetic, geometric and electronic criteria. NICS as a sole descriptor for analysing the antiaromaticity of pentalene on graphene fragments has to be carefully considered while looking through the other aromaticity indicators.
Collapse
Affiliation(s)
- Keerthy P Sudhakaran
- School of Chemistry, Indian Institute of Science Education and Research Thiruvananthapuram, Vithura, Thiruvananthapuram, Kerala, 695551, India.
| | - Alfy Benny
- Department of Chemistry, Princeton University, Princeton, New Jersey 08544, USA
| | - Athira T John
- School of Chemistry, Indian Institute of Science Education and Research Thiruvananthapuram, Vithura, Thiruvananthapuram, Kerala, 695551, India.
| | - Mahesh Hariharan
- School of Chemistry, Indian Institute of Science Education and Research Thiruvananthapuram, Vithura, Thiruvananthapuram, Kerala, 695551, India.
| |
Collapse
|
39
|
H. El-Demerdash S, F. Gad S, M. El-Mehasseb I, E. El-Kelany K. Isosterism in pyrrole via azaboroles substitution, a theoretical investigation for electronic structural, stability and aromaticity. Heliyon 2023; 9:e20542. [PMID: 37810871 PMCID: PMC10551570 DOI: 10.1016/j.heliyon.2023.e20542] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/04/2023] [Revised: 08/26/2023] [Accepted: 09/28/2023] [Indexed: 10/10/2023] Open
Abstract
This work uses ab-initio CBS-QB3 and density functional theory (B3LYP) to analyze the structure, stability, and aromaticity of all isosteric nitrogen-boron pyrroles. The mono-NB unit substituted group of the isosteric NB pyrrole has four isosteres, whereas the multi-NB unit substituted group has two isosteres. These two groups make up all isosteric NB pyrrole. For structural, energetic, magnetic, and electron delocalization criteria, the results highlight the predominance of the PN3B2 isostere and its greater stability over other conformers. In addition, the global reactivity indices, ESP, HOMO-LUMO, and NBO charges have all been estimated to forecast the active side's electron donation and acceptance. These isosteres are categorized as weak electrophiles and marginal nucleophiles. NB-isosteres have poorer stability, HOMO-LUMO gap, and aromaticity than the parent (pyrrole). In general, NB compounds with more ring sharing are less aromatic than NB molecules with less ring sharing. The current study is anticipated to help in understanding of the chemistry of NB substituted molecules and their experimental identification and characterization.
Collapse
Affiliation(s)
| | - Shaimaa F. Gad
- Chemistry Department, Faculty of Science, Kafrelsheikh University, 33516, Kafr el-Sheikh, Egypt
| | - Ibrahim M. El-Mehasseb
- Chemistry Department, Faculty of Science, Kafrelsheikh University, 33516, Kafr el-Sheikh, Egypt
| | - Khaled E. El-Kelany
- Institute of Nanoscience and Nanotechnology, Kafrelsheikh University, 33516, Kafr el-skiekh, Egypt
| |
Collapse
|
40
|
Mizuno Y, Nogata A, Suzuki M, Nakayama KI, Hisaki I, Kishi R, Konishi A, Yasuda M. Synthesis and Characterization of Dibenzothieno[ a, f]pentalenes Enabling Large Antiaromaticity and Moderate Open-Shell Character through a Small Energy Barrier for Bond-Shift Valence Tautomerization. J Am Chem Soc 2023; 145:20595-20609. [PMID: 37695346 DOI: 10.1021/jacs.3c07356] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 09/12/2023]
Abstract
Experimental and theoretical rationalization of bond-shift valence tautomerization, characterized by double-well potential surfaces, is one of the most challenging topics of study among the rich electronic properties of antiaromatic molecules. Although the pseudo-Jahn-Teller effect (PJTE) is an essential effect to provide attractive characteristics of 4nπ systems, an understanding of the structure-property relationship derived from the PJTE for planar 4nπ electron systems is still in its infancy. Herein, we describe the synthesis and characterization of two regioisomers of the thiophene-fused diareno[a,f]pentalenes 6 and 7. The magnetic and optoelectronic properties characterize these sulfur-doped diareno[a,f]pentalenes as open-shell antiaromatic molecules, in sharp contrast to the closed-shell antiaromatic systems of 3 and 5, in which these main cores consist of the same number of π electrons as 6 and 7. Notably, thiophene-fused 6b and 7b showed pronounced antiaromaticity, the strongest among the previous systems, as well as moderate open-shell characteristics. Our experimental and theoretical investigations concluded that these properties of 6b and 7b are derived from the small energy barrier Ea‡ for the bond-shift valence tautomerization. The energy profile of the single crystal of 6b showed the temperature-dependent structural variations assigned to the dynamic mutual exchange between the two Cs-symmetric structures, which was also supported by changes in the chemical shifts of variable-temperature 1H NMR spectra in the solution phase. Both experimental and computational results revealed the importance of introducing heteroaromatic rings into 4nπ systems for controlling the PJTE and manifesting the antiaromatic and open-shell natures originating from the high-symmetric structure. The findings of this study advance the understanding of antiaromaticity characterized by the PJTE by controlling the energy barrier for bond-shift valence tautomerizations, potentially leading to the rational design of optoelectronic devices based on novel antiaromatic molecules possessing the strong contributions of their high-symmetric geometries.
Collapse
Affiliation(s)
- Yusuke Mizuno
- Department of Applied Chemistry, Graduate School of Engineering, Osaka University, 2-1 Yamadaoka, Suita, Osaka 565-0871, Japan
| | - Akira Nogata
- Department of Applied Chemistry, Graduate School of Engineering, Osaka University, 2-1 Yamadaoka, Suita, Osaka 565-0871, Japan
| | - Mitsuharu Suzuki
- Department of Applied Chemistry, Graduate School of Engineering, Osaka University, 2-1 Yamadaoka, Suita, Osaka 565-0871, Japan
| | - Ken-Ichi Nakayama
- Department of Applied Chemistry, Graduate School of Engineering, Osaka University, 2-1 Yamadaoka, Suita, Osaka 565-0871, Japan
| | - Ichiro Hisaki
- Division of Chemistry, Graduate School of Engineering Science, Osaka University, 1-3 Machikaneyama, Toyonaka, Osaka 560-8531, Japan
| | - Ryohei Kishi
- Department of Materials Engineering Science, Graduate School of Engineering Science, Osaka University, 1-3 Machikaneyama, Toyonaka, Osaka 560-8531, Japan
- Center for Quantum Information and Quantum Biology (QIQB), Osaka University, Toyonaka, Osaka 560-8531, Japan
- Innovative Catalysis Science Division, Institute for Open and Transdisciplinary Research Initiatives (ICS-OTRI), Osaka University, Suita, Osaka 565-0871, Japan
| | - Akihito Konishi
- Department of Applied Chemistry, Graduate School of Engineering, Osaka University, 2-1 Yamadaoka, Suita, Osaka 565-0871, Japan
- Innovative Catalysis Science Division, Institute for Open and Transdisciplinary Research Initiatives (ICS-OTRI), Osaka University, Suita, Osaka 565-0871, Japan
| | - Makoto Yasuda
- Department of Applied Chemistry, Graduate School of Engineering, Osaka University, 2-1 Yamadaoka, Suita, Osaka 565-0871, Japan
- Innovative Catalysis Science Division, Institute for Open and Transdisciplinary Research Initiatives (ICS-OTRI), Osaka University, Suita, Osaka 565-0871, Japan
| |
Collapse
|
41
|
Takase M, Takata T, Oki K, Mori S, Uno H. Substituent effects on paratropicity and diatropicity in π-extended hexapyrrolohexaazacoronene. Chem Sci 2023; 14:7036-7043. [PMID: 37389264 PMCID: PMC10306074 DOI: 10.1039/d2sc07037e] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/23/2022] [Accepted: 06/04/2023] [Indexed: 07/01/2023] Open
Abstract
Research into the application of antiaromatic compounds as molecular materials is an attractive strategy in the development of electronic materials. Antiaromatic compounds have traditionally been considered to be unstable, and thus, the creation of stable antiaromatic compounds has been sought in the field of organic chemistry. Recently, some studies have been reported on the synthesis, isolation, and elucidation of the physical properties of compounds with stability and definitive antiaromatic properties. In general, antiaromatic compounds are considered to be more susceptible to substituents due to their inherently narrow HOMO-LUMO gap compared to aromatic compounds. However, there have been no studies examining substituent effects in antiaromatic compounds. In this study, we have developed a synthetic method to introduce various substituents into π-extended hexapyrrolohexaazacoronene (homoHPHAC+), one of the stable and clearly antiaromatic compounds, and investigated the substituent effects on the optical, redox, and geometrical properties and paratropicity of a series of compounds. In addition, the properties of the two-electron oxidized form, homoHPHAC3+, were investigated. Control of electronic properties by introducing substituents into antiaromatic compounds provides a new design guideline for molecular materials.
Collapse
Affiliation(s)
- Masayoshi Takase
- Graduate School of Science and Engineering, Ehime University Matsuyama 790-8577 Japan
- Research Unit on Molecular Materials Science for Toroidal π-Electron Systems, Ehime University Matsuyama 790-8577 Japan
| | - Toranosuke Takata
- Graduate School of Science and Engineering, Ehime University Matsuyama 790-8577 Japan
| | - Kosuke Oki
- Graduate School of Science and Engineering, Ehime University Matsuyama 790-8577 Japan
| | - Shigeki Mori
- Research Unit on Molecular Materials Science for Toroidal π-Electron Systems, Ehime University Matsuyama 790-8577 Japan
- Advanced Research Support Center (ADRES), Ehime University Matsuyama 790-8577 Japan
| | - Hidemitsu Uno
- Graduate School of Science and Engineering, Ehime University Matsuyama 790-8577 Japan
| |
Collapse
|
42
|
Merino G, Solà M, Fernández I, Foroutan-Nejad C, Lazzeretti P, Frenking G, Anderson HL, Sundholm D, Cossío FP, Petrukhina MA, Wu J, Wu JI, Restrepo A. Aromaticity: Quo Vadis. Chem Sci 2023; 14:5569-5576. [PMID: 37265727 PMCID: PMC10231312 DOI: 10.1039/d2sc04998h] [Citation(s) in RCA: 43] [Impact Index Per Article: 43.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/07/2022] [Accepted: 02/22/2023] [Indexed: 07/25/2023] Open
Abstract
Aromaticity is one of the most deeply rooted concepts in chemistry. But why, if two-thirds of existing compounds can be classified as aromatic, is there no consensus on what aromaticity is? σ-, π-, δ-, spherical, Möbius, or all-metal aromaticity… why are so many attributes needed to specify a property? Is aromaticity a dubious concept? This perspective aims to reflect where the aromaticity community is and where it is going.
Collapse
Affiliation(s)
- Gabriel Merino
- Departamento de Física Aplicada, Centro de Investigación y de Estudios Avanzados Unidad Mérida, km 6 Antigua Carretera a Progreso, Apdo. Postal 73, Cordemex 97310 Mérida Yucatán Mexico
| | - Miquel Solà
- Institut de Química Computacional i Catàlisi and Department de Química, Universitat de Girona C/M. Aurèlia Capmany, 69 Girona 17003 Catalonia Spain
| | - Israel Fernández
- Departamento de Química Orgánica and Centro de Innovación en Química Avanzada (ORFEO-CINQA), Facultad de Ciencias Químicas, Universidad Complutense de Madrid 28040 Madrid Spain
| | - Cina Foroutan-Nejad
- Institute of Organic Chemistry, Polish Academy of Sciences Kasprzaka 44/52 01-224 Warsaw Poland
| | - Paolo Lazzeretti
- Dipartimento di Chimica e Biologia "A. Zambelli", Università degli Studi di Salerno via Giovanni Paolo II 132, Fisciano 84084 SA Italy
| | - Gernot Frenking
- Fachbereich Chemie, Philipps-Universität Marburg Hans-Meerwein-Strasse 4, D-35043 Marburg Germany
| | | | - Dage Sundholm
- Department of Chemistry, Faculty of Science, University of Helsinki P.O. Box 55, A. I. Virtasen aukio 1 FIN-00014 Helsinki Finland
| | - Fernando P Cossío
- Departamento de Química Orgánica I, Instituto de Innovaciónen Química Avanzada (ORFEO-CINQA), University of the Basque Country (UPV/EHU) Paseo Manuel Lardizabal 3 20018 Donostia/San Sebastián Spain
| | - Marina A Petrukhina
- Department of Chemistry, University at Albany, State University of New York Albany New York 12222 USA
| | - Jishan Wu
- Department of Chemistry, National University of Singapore 3 Science Drive 3 Singapore 117543 Singapore
| | - Judy I Wu
- Department of Chemistry, University of Houston Houston Texas 77204 USA
| | - Albeiro Restrepo
- Instituto de Química, Universidad de Antioquia Calle 70 No. 52-21 050010 Medellín Colombia
| |
Collapse
|
43
|
Li S, Sun Y, Li X, Smaga O, Koniarz S, Pawlicki M, Chmielewski PJ. Oxidative insertion of amines into conjugated macrocycles: transformation of antiaromatic norcorrole into aromatic azacorrole. Chem Commun (Camb) 2023; 59:3739-3742. [PMID: 36897336 DOI: 10.1039/d2cc06648c] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 03/11/2023]
Abstract
A new group of aromatic porphyrinoids was obtained by an oxidative insertion of primary amines into the antiaromatic ring of 5,14-dimesityl-norcorrolatonickel(II) activated by iodosobenzene. The substituted 10-azacorroles thus formed were characterized by spectroscopic and electrochemical methods, and XRD analysis. Protonated forms of azacorroles were shown to remain aromatic despite disconnection of the original π-electron delocalization path.
Collapse
Affiliation(s)
- Sha Li
- Key Laboratory of Theoretical Organic Chemistry and Functional Molecules, Ministry of Education, School of Chemistry and Chemical Engineering, Hunan University of Science and Technology Xiangtan, Hunan 411201, China.
| | - Yahan Sun
- Key Laboratory of Theoretical Organic Chemistry and Functional Molecules, Ministry of Education, School of Chemistry and Chemical Engineering, Hunan University of Science and Technology Xiangtan, Hunan 411201, China.
| | - Xiaofang Li
- Key Laboratory of Theoretical Organic Chemistry and Functional Molecules, Ministry of Education, School of Chemistry and Chemical Engineering, Hunan University of Science and Technology Xiangtan, Hunan 411201, China.
| | - Oskar Smaga
- Department of Chemistry, University of Wrocław, F. Joliot-Curie 14, Wrocław 50 383, Poland.
| | - Sebastian Koniarz
- Department of Chemistry, University of Wrocław, F. Joliot-Curie 14, Wrocław 50 383, Poland.
| | - Miłosz Pawlicki
- Faculty of Chemistry, Jagiellonian University, Gronostajowa 2, Kraków 30 387, Poland
| | - Piotr J Chmielewski
- Department of Chemistry, University of Wrocław, F. Joliot-Curie 14, Wrocław 50 383, Poland.
| |
Collapse
|
44
|
Jhang SJ, Pandidurai J, Chu CP, Miyoshi H, Takahara Y, Miki M, Sotome H, Miyasaka H, Chatterjee S, Ozawa R, Ie Y, Hisaki I, Tsai CL, Cheng YJ, Tobe Y. s-Indacene Revisited: Modular Synthesis and Modulation of Structures and Molecular Orbitals of Hexaaryl Derivatives. J Am Chem Soc 2023; 145:4716-4729. [PMID: 36796008 DOI: 10.1021/jacs.2c13159] [Citation(s) in RCA: 12] [Impact Index Per Article: 12.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/18/2023]
Abstract
Though s-indacene is an intriguing antiaromatic hydrocarbon of 12 π-electrons, it has been underrepresented due to the lack of efficient and versatile methods to prepare stable derivatives. Herein we report a concise and modular synthetic method for hexaaryl-s-indacene derivatives bearing electron-donating/-accepting groups at specific positions to furnish C2h-, D2h-, and C2v-symmetric substitution patterns. We also report the effects of substituents on their molecular structures, frontier molecular orbital (MO) levels, and magnetically induced ring current tropicities. Both theoretical calculations and X-ray structure analyses indicate that the derivatives of the C2h-substitution pattern adopt different C2h structures with significant bond length alternation depending on the electronic property of the substituents. Due to the nonuniform distribution of the frontier MOs, their energy levels are selectively modulated by the electron-donating substituents. This leads to the inversion of the HOMO and HOMO-1 sequences with respect to those of the intrinsic s-indacene as theoretically predicted and experimentally proven by the absorption spectra at visible and near-infrared regions. The NICS values and the 1H NMR chemical shifts of the s-indacene derivatives indicate their weak antiaromaticity. The different tropicities are explained by the modulation of the HOMO and HOMO-1 levels. In addition, for the hexaxylyl derivative, weak fluorescence from the S2 excited state was detected due to the large energy gap between the S1 and S2 states. Notably, an organic field-effect transistor (OFET) fabricated using the hexaxylyl derivative exhibited moderate hole carrier mobility, a result which opens the door for optoelectronic applications of s-indacene derivatives.
Collapse
Affiliation(s)
- Shun-Jie Jhang
- Department of Applied Chemistry, National Yang Ming Chiao Tung University, 1001 Ta Hsueh Road, Hsinchu 30010, Taiwan
| | - Jayabalan Pandidurai
- Department of Applied Chemistry, National Yang Ming Chiao Tung University, 1001 Ta Hsueh Road, Hsinchu 30010, Taiwan
| | - Ching-Piao Chu
- Department of Applied Chemistry, National Yang Ming Chiao Tung University, 1001 Ta Hsueh Road, Hsinchu 30010, Taiwan
| | - Hirokazu Miyoshi
- Division of Frontier Materials Science, Graduate School of Engineering Science, Osaka University, Toyonaka, Osaka 560-8531, Japan
| | - Yuta Takahara
- Division of Frontier Materials Science, Graduate School of Engineering Science, Osaka University, Toyonaka, Osaka 560-8531, Japan
| | - Masahito Miki
- Division of Frontier Materials Science, Graduate School of Engineering Science, Osaka University, Toyonaka, Osaka 560-8531, Japan
| | - Hikaru Sotome
- Division of Chemistry, Graduate School of Engineering Science, Osaka University, Toyonaka, Osaka 560-8531, Japan
| | - Hiroshi Miyasaka
- Division of Chemistry, Graduate School of Engineering Science, Osaka University, Toyonaka, Osaka 560-8531, Japan
| | - Shreyam Chatterjee
- Nanoscience and Nanotechnology Center, The Institute of Scientific and Industrial Research (SANKEN), Osaka University, Ibaraki, Osaka 567-0047, Japan
| | - Rumi Ozawa
- Nanoscience and Nanotechnology Center, The Institute of Scientific and Industrial Research (SANKEN), Osaka University, Ibaraki, Osaka 567-0047, Japan
| | - Yutaka Ie
- Nanoscience and Nanotechnology Center, The Institute of Scientific and Industrial Research (SANKEN), Osaka University, Ibaraki, Osaka 567-0047, Japan
| | - Ichiro Hisaki
- Division of Chemistry, Graduate School of Engineering Science, Osaka University, Toyonaka, Osaka 560-8531, Japan
| | - Chia-Lin Tsai
- Department of Applied Chemistry, National Yang Ming Chiao Tung University, 1001 Ta Hsueh Road, Hsinchu 30010, Taiwan
| | - Yen-Ju Cheng
- Department of Applied Chemistry, National Yang Ming Chiao Tung University, 1001 Ta Hsueh Road, Hsinchu 30010, Taiwan
| | - Yoshito Tobe
- Department of Applied Chemistry, National Yang Ming Chiao Tung University, 1001 Ta Hsueh Road, Hsinchu 30010, Taiwan.,Division of Frontier Materials Science, Graduate School of Engineering Science, Osaka University, Toyonaka, Osaka 560-8531, Japan.,Nanoscience and Nanotechnology Center, The Institute of Scientific and Industrial Research (SANKEN), Osaka University, Ibaraki, Osaka 567-0047, Japan
| |
Collapse
|
45
|
Rafat R, Nakhaei E, Zargari F, Gorgichi F, Nowroozi A. Quantum chemical study of tautomeric equilibriums, intramolecular hydrogen bonds, and π-electron delocalization in the first singlet and triplet excited states of 2-selenoformyl-3-thioxo-propionaldehyde. J Sulphur Chem 2023. [DOI: 10.1080/17415993.2023.2171292] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 03/07/2023]
Affiliation(s)
- Ramin Rafat
- Department of Chemistry, Faculty of Science, University of Sistan and Baluchestan (USB), Zahedan, Iran
| | - Ebrahim Nakhaei
- Department of Chemistry, Faculty of Science, University of Sistan and Baluchestan (USB), Zahedan, Iran
| | - Farshid Zargari
- Department of Chemistry, Faculty of Science, University of Sistan and Baluchestan (USB), Zahedan, Iran
| | - Faezeh Gorgichi
- Department of Chemistry, Faculty of Science, University of Sistan and Baluchestan (USB), Zahedan, Iran
| | - Alireza Nowroozi
- Department of Chemistry, Faculty of Science, University of Sistan and Baluchestan (USB), Zahedan, Iran
| |
Collapse
|
46
|
Hoelm M, Adamczyk J, Wzgarda-Raj K, Palusiak M. Effect of a Substituent on the Properties of Salicylaldehyde Hydrazone Derivatives. J Org Chem 2023; 88:2132-2139. [PMID: 36735741 PMCID: PMC9942203 DOI: 10.1021/acs.joc.2c02547] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
Abstract
The present study investigates the effect of the substitution of salicylaldehyde hydrazones at two selected positions, i.e., the para-position with regard to the proton-donating and proton-accepting centers forming the hydrogen bridge. A detailed analysis of structural data obtained by theoretical approaches and X-ray experiments, together with original resonance Hammett's constants, indicates that the strength of the intramolecular hydrogen bonding present in salicylaldehyde hydrazones can be selectively modulated by substitution of the parent molecular system with the chemical group of known π-electron-donating or -accepting properties. Our findings provide an insight into planning synthesis pathways for salicylaldehyde hydrazone species and predicting their result with regard to their H-bonding and related physical and chemical properties.
Collapse
Affiliation(s)
- Marta Hoelm
- Department
of Physical Chemistry, Faculty of Chemistry, University of Lodz, Pomorska 163/165, Lodz90-236, Poland
| | - Justyna Adamczyk
- Department
of Organic and Applied Chemistry, Faculty of Chemistry, University of Lodz, Tamka 12, Lodz91-403, Poland
| | - Kinga Wzgarda-Raj
- Department
of Physical Chemistry, Faculty of Chemistry, University of Lodz, Pomorska 163/165, Lodz90-236, Poland
| | - Marcin Palusiak
- Department
of Physical Chemistry, Faculty of Chemistry, University of Lodz, Pomorska 163/165, Lodz90-236, Poland,
| |
Collapse
|
47
|
Kato M, Kim J, Oh J, Shimizu D, Fukui N, Shinokubo H. Near-Infrared-Responsive Hydrocarbons Designed by π-Extension of Indeno[1,2,3,4-pgra]perylene at the 1,2,12-Positions. Chemistry 2023; 29:e202300249. [PMID: 36705165 DOI: 10.1002/chem.202300249] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/25/2023] [Revised: 01/26/2023] [Accepted: 01/27/2023] [Indexed: 01/28/2023]
Abstract
The relationship between the overall electronic structure of π-conjugated molecules and the arrangement of their constituent elements is of fundamental importance. Establishing rational design guidelines for conjugated hydrocarbons with narrow HOMO-LUMO gaps is useful to develop near-infrared (NIR) responsive dyes and redox-active materials. This study describes the synthesis and properties of three conjugated hydrocarbons, i. e., an indenonaphthoperylene, an indenoterrylene, and a diindenoterrylene. These molecules exhibit NIR absorption despite the absence of significant antiaromaticity and diradical character. Notably, the indenonaphthoperylene exhibits red-to-NIR emission in the 620-850 nm region. The indenoterrylene and the diindenoterrylene exhibit NIR absorption tailing to 870 and 940 nm, respectively. Moreover, the effect of the π-extension of indenoperylene is disclosed in order to propose guidelines for achieving a narrow HOMO-LUMO gap with negligible antiaromaticity and diradical character.
Collapse
Affiliation(s)
- Masaki Kato
- Department of Molecular and Macromolecular Chemistry, Graduate School of Engineering, Integrated Research Consortium on Chemical Science (IRCCS), Nagoya University, Furo-cho, Chikusa-ku, 464-8603, Nagoya, Japan
| | - Jinseok Kim
- Spectroscopy Laboratory for Functional π-Electronic Systems and, Department of Chemistry, Yonsei University, 03722, Seoul, Korea
| | - Juwon Oh
- Spectroscopy Laboratory for Functional π-Electronic Systems and, Department of Chemistry, Yonsei University, 03722, Seoul, Korea.,Department of Chemistry and, Department of ICT Environmental Health System, Soonchunhyang University, 31538, Asan, Korea
| | - Daiki Shimizu
- Department of Synthetic Chemistry and Biological Chemistry, Graduate School of Engineering, Kyoto University, Nishikyo-ku, 615-8510, Kyoto, Japan
| | - Norihito Fukui
- Department of Molecular and Macromolecular Chemistry, Graduate School of Engineering, Integrated Research Consortium on Chemical Science (IRCCS), Nagoya University, Furo-cho, Chikusa-ku, 464-8603, Nagoya, Japan.,PRESTO, Japan Science and Technology Agency (JST), 332-0012, Kawaguchi, Saitama, Japan
| | - Hiroshi Shinokubo
- Department of Molecular and Macromolecular Chemistry, Graduate School of Engineering, Integrated Research Consortium on Chemical Science (IRCCS), Nagoya University, Furo-cho, Chikusa-ku, 464-8603, Nagoya, Japan
| |
Collapse
|
48
|
Tajima K, Matsuo K, Yamada H, Fukui N, Shinokubo H. Diazazethrene bisimide: a strongly electron-accepting π-system synthesized via the incorporation of both imide substituents and imine-type nitrogen atoms into zethrene. Chem Sci 2023; 14:635-642. [PMID: 36741537 PMCID: PMC9847653 DOI: 10.1039/d2sc05992d] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/28/2022] [Accepted: 12/03/2022] [Indexed: 12/12/2022] Open
Abstract
The development of highly electron-accepting π-systems is a fundamentally challenging issue despite their potential applications as high-performance n-type organic semiconductors, organic rechargeable batteries, and stable redox-active organocatalysts. Herein, we demonstrate that the incorporation of both imide substituents and imine-type nitrogen atoms into zethrene affords the strongly electron-accepting π-system diazazethrene bisimide (DAZBI). DAZBI has a low-lying LUMO (-4.3 eV vs. vacuum) and is readily reduced by the weak reductant l-ascorbic acid to afford the corresponding dihydro species. The injection of two electrons into DAZBI provides the corresponding dianion. These reduced species display remarkable stability, even under ambient conditions, and an intense red fluorescence. A DAZBI dimer, which was also synthesized, effectively accommodated four electrons upon electron injection.
Collapse
Affiliation(s)
- Keita Tajima
- Department of Molecular and Macromolecular Chemistry, Graduate School of Engineering, Integrated Research Consortium on Chemical Science (IRCCS), Nagoya University Furo-cho, Chikusa-ku Nagoya Aichi 464-8603 Japan
| | - Kyohei Matsuo
- Division of Material Science, Graduate of School of Science and Technology, Nara Institute of Science and Technology 8916-5 Takayama-cho, Ikoma Nara 630-0912 Japan
| | - Hiroko Yamada
- Division of Material Science, Graduate of School of Science and Technology, Nara Institute of Science and Technology 8916-5 Takayama-cho, Ikoma Nara 630-0912 Japan
| | - Norihito Fukui
- Department of Molecular and Macromolecular Chemistry, Graduate School of Engineering, Integrated Research Consortium on Chemical Science (IRCCS), Nagoya University Furo-cho, Chikusa-ku Nagoya Aichi 464-8603 Japan
- PRESTO, Japan Science and Technology Agency (JST) Kawaguchi Saitama 332-0012 Japan
| | - Hiroshi Shinokubo
- Department of Molecular and Macromolecular Chemistry, Graduate School of Engineering, Integrated Research Consortium on Chemical Science (IRCCS), Nagoya University Furo-cho, Chikusa-ku Nagoya Aichi 464-8603 Japan
| |
Collapse
|
49
|
Acoplanarity, Aromaticity, Chirality, and Helical Twisting Power of Chlorin e6 13(N)-Methylamide-15,17-dimethyl Ester Complexes: Effect of a Metal. INORGANICS 2023. [DOI: 10.3390/inorganics11010024] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/04/2023] Open
Abstract
The experimental and theoretical study of the influence of metal complexing on geometry, aromaticity, chirality, and the ability to twist the nematic phase by complexes based on modified natural chlorin e6 was carried out. The geometry optimization of the chlorin e6 13(N)-methylamide-15,17-dimethyl ester (MADMECl) and its Zn, Cu, and Ni complexes by DFT (CAM-B3LYP/6–31 G(d,p) functional) method was performed. Based on these calculations, the acoplanarity degree of the macrocyclic ligand and the distortion energy of its dianion were estimated, which allowed the arrangement of the MADMECl complexes in the series Ni > Cu > Zn. Aromaticity was evaluated using the NICS criterion (nuclear independent chemical shift). An increase in the degree of aromaticity of the macrocycle upon complex formation was established. At the same time, the aromaticity of the inner conjugation contour corresponds to the same series as the acoplanarity, while the outer π-delocalization is characterized by the reverse sequence. An experimental evaluation of the electron circular dichroism of the Soret and the Q-bands, as well as the g-factor of dissymmetry, was carried out. The growth of these parameters with an increase in the degree of acoplanarity and aromaticity of the internal conjugation contour was determined. The induction of helical phases in mixtures of nematic liquid crystals (LCs) based on cyanobiphenyls and MADMECl macrocyclic metal complexes was studied by polarization microscopy, and the clearance temperatures and helix pitch of the mesophases were measured. A strong effect of the metal on the phase transition temperature and helical twisting power was established.
Collapse
|
50
|
FUJIMORI S, MIZUHATA Y, TOKITOH N. Recent progress in the chemistry of heavy aromatics. PROCEEDINGS OF THE JAPAN ACADEMY. SERIES B, PHYSICAL AND BIOLOGICAL SCIENCES 2023; 99:480-512. [PMID: 38072454 PMCID: PMC10822718 DOI: 10.2183/pjab.99.027] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/19/2023] [Accepted: 09/25/2023] [Indexed: 12/18/2023]
Abstract
The aromaticity and synthetic application of "heavy benzenes", i.e., benzenes containing a heavier Group 14 element (Si, Ge, Sn, and Pb) in place of skeletal carbon, have been the targets of many theoretical and synthetic studies. Although the introduction of a sterically demanding substituent enabled us to synthesize and isolate heavy aromatic species as a stable compound by suppressing their high reactivity and tendency to polymerize, the existence of a protection group is an obstruction to the development of functional materials based on heavy aromatics. This review will delineate the most recent topics in the chemistry of heavy aromatics, i.e., the chemistry of "metallabenzenyl anions", which are the heavier Group 14 element analogs of phenyl anions stabilized by taking advantage of charge repulsion instead of steric protection.
Collapse
Affiliation(s)
- Shiori FUJIMORI
- Institute for Chemical Research, Kyoto University, Kyoto, Japan
| | | | | |
Collapse
|