1
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Cummings E, Karadakov PB. Aromaticity in the Electronic Ground and Lowest Triplet States of Molecules with Fused Thiophene Rings. Chemistry 2024; 30:e202303724. [PMID: 38038597 DOI: 10.1002/chem.202303724] [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: 11/09/2023] [Revised: 11/30/2023] [Accepted: 12/01/2023] [Indexed: 12/02/2023]
Abstract
Analysis of the variations of the off-nucleus isotropic magnetic shielding, σiso(r), around thiophene, thienothiophenes, dithienothiophenes and sulflowers in their electronic ground (S0) and lowest triplet (T1) states reveals that some of the features of aromaticity and bonding in these molecules do not fit in with predictions based on the popular Hückel's and Baird's rules. Despite having 4n π electrons, the S0 states of the sulflowers are shown to be aromatic, due to the local aromaticities of the individual thiophene rings. To reduce its T1 antiaromaticity, the geometry of thiophene changes considerably between S0 and T1: In addition to losing planarity, the carbon-carbon two 'double' and one 'single' bonds in S0 turn into two 'single' and one 'double' bonds in T1. Well-defined Baird-style aromaticity reversals are observed between the S0 and T1 states of only three of the twelve thiophene-based compounds investigated in this work, in contrast, the sulflower with six thiophene rings which is weakly aromatic in S0 becomes more aromatic in T1. The results suggest that the change in aromaticity between the S0 and T1 states in longer chains of fused rings is likely to affect mostly the central ring (or the pair of central rings); rings sufficiently far away from the central ring(s) can retain aromatic character.
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Affiliation(s)
- Edward Cummings
- Department of Chemistry, University of York, Heslington, York, YO10 5DD, UK
| | - Peter B Karadakov
- Department of Chemistry, University of York, Heslington, York, YO10 5DD, UK
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2
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Jalife S, Tsybizova A, Gershoni-Poranne R, Wu JI. Modulating Paratropicity in Heteroarene-Fused Expanded Pentalenes. Org Lett 2024; 26:1293-1298. [PMID: 38307038 DOI: 10.1021/acs.orglett.4c00188] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/04/2024]
Abstract
Pentalenes are formally eight-π-electron antiaromatic, but π-expanded pentalenes can display varying levels of paratropicity depending on the choice of annelated (hetero)arenes and the geometry of π-expansion (i.e., linear vs bent topologies) around the [4n] core. Here, we explain the effects of annelation on the paratropicity of π-expanded pentalenes by relating the electronic structure of pentalenes to a pair of conjoined pentafulvenes.
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Affiliation(s)
- Said Jalife
- Department of Chemistry, University of Houston, Houston, Texas 77204-5003, United States
| | - Alexandra Tsybizova
- Laboratory for Organic Chemistry, ETH Zurich, Vladimir-Prelog-Weg 2, Zurich 8092, Switzerland
| | - Renana Gershoni-Poranne
- Schulich Faculty of Chemistry, Technion - Israel Institute of Technology, Technion City, Haifa 32000, Israel
| | - Judy I Wu
- Department of Chemistry, University of Houston, Houston, Texas 77204-5003, United States
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3
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Murai M, Enoki T, Yamaguchi S. Dithienoazepine-Based Near-Infrared Dyes: Janus-Faced Effects of a Thiophene-Fused Structure on Antiaromatic Azepines. Angew Chem Int Ed Engl 2023; 62:e202311445. [PMID: 37699858 DOI: 10.1002/anie.202311445] [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: 08/07/2023] [Revised: 09/10/2023] [Accepted: 09/12/2023] [Indexed: 09/14/2023]
Abstract
We here disclose that the incorporation of thiophene rings into a seven-membered 8π azepine in a fused fashion produces a useful antiaromatic core for near-infrared (NIR) dyes. In contrast to dibenzazepine derivatives with bent structures, dithieno-fused derivatives with electron-accepting groups adopt flat conformations in the ground state. The dithieno-fused derivatives exhibited broad absorption spectra that cover the visible region as well as sharp emission bands in the NIR region, which are considerably red-shifted relative to those of the dibenzo-fused congeners. Theoretical study revealed two contradictory effects of the less-aromatic thiophene-fused structure, i.e., the enhancement of the antiaromaticity of the adjacent azepine ring and the relief of the antiaromaticity through the contribution of a quinoidal resonance form. The combination of the dithienoazepine core with cationic electron-accepting groups produced a NIR fluorescent dye with an emission at 878 nm in solution.
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Affiliation(s)
- Masahito Murai
- Department of Chemistry, Graduate School of Science, and Integrated Research Consortium on Chemical Sciences (IRCCS), Nagoya University, Furo, Chikusa, Nagoya, 464-8602, Japan
| | - Takahiro Enoki
- Department of Chemistry, Graduate School of Science, and Integrated Research Consortium on Chemical Sciences (IRCCS), Nagoya University, Furo, Chikusa, Nagoya, 464-8602, Japan
| | - Shigehiro Yamaguchi
- Department of Chemistry, Graduate School of Science, and Integrated Research Consortium on Chemical Sciences (IRCCS), Nagoya University, Furo, Chikusa, Nagoya, 464-8602, Japan
- Institute of Transformative Bio-Molecules (WPI-ITbM), Nagoya University, Furo, Chikusa, Nagoya, 464-8601, Japan
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4
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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.
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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
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5
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Lee S, Wang Y, Dutta R, Lee CH, Sessler JL, Kim D. Xanthene-Separated 24 π-Electron Antiaromatic Rosarin Dimer. Chemistry 2023; 29:e202301501. [PMID: 37205632 DOI: 10.1002/chem.202301501] [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: 05/12/2023] [Revised: 05/18/2023] [Accepted: 05/19/2023] [Indexed: 05/21/2023]
Abstract
Antiaromatic molecules have recently received attention because of their intrinsic properties, such as high reactivity and their narrow HOMO-LUMO gaps. Stacking of antiaromatic molecules has been predicted to induce three-dimensional aromaticity via frontier orbital interactions. Here, we report a covalently linked π-π stacked rosarin dimer that has been examined experimentally by steady-state absorption and transient absorption measurements and theoretically by quantum chemical calculations, including time-dependent density functional theory, anisotropy of induced current density, and nucleus-independent chemical shift calculations. Relative to the corresponding monomer, the dimer exhibits diminished antiaromaticity upon lowering the temperature to 77 K, a finding ascribed to intramolecular interactions between the macrocyclic rosarin subunits.
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Affiliation(s)
- Seokwon Lee
- Department of Chemistry, Spectroscopy Laboratory for Functional π-Electronic Systems, Yonsei University, Seoul, 03722, Korea
| | - Yuying Wang
- Department of Chemistry, The University of Texas at Austin, Austin, Texas, 78712-1224, USA
| | - Ranjan Dutta
- School of Applied Science and Humanities, Haldia Institute of Technology, Haldia, West Bengal, 721657, India
| | - Chang-Hee Lee
- Department of Chemistry, Kangwon National University, Chun Cheon, 200-701, Korea
| | - Jonathan L Sessler
- Department of Chemistry, The University of Texas at Austin, Austin, Texas, 78712-1224, USA
| | - Dongho Kim
- Department of Chemistry, Spectroscopy Laboratory for Functional π-Electronic Systems, Yonsei University, Seoul, 03722, Korea
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6
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Adachi Y, Hasegawa T, Ohshita J. Highly luminescent antiaromatic diborinines with fused thiophene rings. Dalton Trans 2023. [PMID: 37357987 DOI: 10.1039/d3dt01841e] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/27/2023]
Abstract
Tricoordinate boron-incorporated π-conjugated systems are widely investigated as optoelectronic materials because of their unique p-π* orbital interactions and high Lewis acidity. Among them, thiophene-fused diborinines are characterized by moderate antiaromaticity and extended conjugation. In this work, we have developed two new dithienodiborinines with C2h and C2v symmetries, which exhibited completely different optical properties. The thiophene-fused diborinines synthesized in this study showed excellent fluorescence properties both in solution and in the solid state, with quantum yields of up to 95%. The high antiaromaticity enhanced the Lewis acidity of the boron centers, as proven by the large association constants with fluoride ion estimated from titration experiments. The high Lewis acidity and the superior luminescence property have enabled their application as fluorescent sensor materials for the detection of ammonia vapor.
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Affiliation(s)
- Yohei Adachi
- Graduate School of Advanced Science and Engineering, Hiroshima University, Higashi-Hiroshima 739-8527, Japan.
| | - Takumi Hasegawa
- Graduate School of Advanced Science and Engineering, Hiroshima University, Higashi-Hiroshima 739-8527, Japan.
| | - Joji Ohshita
- Graduate School of Advanced Science and Engineering, Hiroshima University, Higashi-Hiroshima 739-8527, Japan.
- Digital Monozukuri (Manufacturing) Education and Research Center, Hiroshima University, Higashi-Hiroshima 739-0046, Japan.
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7
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Coburger P, Schweinzer C, Li Z, Grützmacher H. Reversible Single Electron Redox Steps Convert Polycycles with a C 3 P 3 Core to a Planar Triphosphinine. Angew Chem Int Ed Engl 2023; 62:e202214548. [PMID: 36688727 DOI: 10.1002/anie.202214548] [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: 10/03/2022] [Revised: 12/18/2022] [Accepted: 01/23/2023] [Indexed: 01/24/2023]
Abstract
Reaction of the imidazolium-stabilized diphosphete-diide IDP with trityl phosphaalkyne affords a mixture which contains the molecules 1 a and 1 b with a central C3 P3 core, which formally carries a two-fold negative charge. In order to avoid the formation of an antiaromatic 8π electron system within a conjugated dianionic six-membered [C3 P3 ]2- ring, 1 a adopts a bicyclic [3.1.0] and 1 b a tricyclic [2.2.0.0] structure which are in a dynamic equilibrium. 1 a, b can be reversibly oxidized to a triphosphinine dication [5]2+ with a central flat aromatic six-membered C3 P3 ring. This two-electron redox reaction occurs in two single-electron transfer steps via the 7π-radical cation [4]⋅+ , which could also be isolated and fully characterized. The profound reversible structural change observed for the two-electron redox couple [5]2+ /1 a, b is in sharp contrast to the C6 H6 /[C6 H6 ]2- couple, which undergoes only a modest structural deformation.
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Affiliation(s)
- Peter Coburger
- Department of Chemistry and Applied Biosciences, ETH Zürich, Vladimir-Prelog-Weg 1-5/10, 8093, Zürich, Switzerland
| | - Clara Schweinzer
- Department of Chemistry and Applied Biosciences, ETH Zürich, Vladimir-Prelog-Weg 1-5/10, 8093, Zürich, Switzerland
| | - Zhongshu Li
- Lehn Institute of Functional Materials (LIFM), School of Chemistry, Sun Yat-Sen University, 510275, Guangzhou, China.,State Key Laboratory of Elemento-Organic Chemistry, Nankai University, 30071, Tianjin, China
| | - Hansjörg Grützmacher
- Department of Chemistry and Applied Biosciences, ETH Zürich, Vladimir-Prelog-Weg 1-5/10, 8093, Zürich, Switzerland
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8
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Sprachmann J, Wachsmuth T, Bhosale M, Burmeister D, Smales GJ, Schmidt M, Kochovski Z, Grabicki N, Wessling R, List-Kratochvil EJW, Esser B, Dumele O. Antiaromatic Covalent Organic Frameworks Based on Dibenzopentalenes. J Am Chem Soc 2023; 145:2840-2851. [PMID: 36701177 DOI: 10.1021/jacs.2c10501] [Citation(s) in RCA: 11] [Impact Index Per Article: 11.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/27/2023]
Abstract
Despite their inherent instability, 4n π systems have recently received significant attention due to their unique optical and electronic properties. In dibenzopentalene (DBP), benzanellation stabilizes the highly antiaromatic pentalene core, without compromising its amphoteric redox behavior or small HOMO-LUMO energy gap. However, incorporating such molecules in organic devices as discrete small molecules or amorphous polymers can limit the performance (e.g., due to solubility in the battery electrolyte solution or low internal surface area). Covalent organic frameworks (COFs), on the contrary, are highly ordered, porous, and crystalline materials that can provide a platform to align molecules with specific properties in a well-defined, ordered environment. We synthesized the first antiaromatic framework materials and obtained a series of three highly crystalline and porous COFs based on DBP. Potential applications of such antiaromatic bulk materials were explored: COF films show a conductivity of 4 × 10-8 S cm-1 upon doping and exhibit photoconductivity upon irradiation with visible light. Application as positive electrode materials in Li-organic batteries demonstrates a significant enhancement of performance when the antiaromaticity of the DBP unit in the COF is exploited in its redox activity with a discharge capacity of 26 mA h g-1 at a potential of 3.9 V vs. Li/Li+. This work showcases antiaromaticity as a new design principle for functional framework materials.
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Affiliation(s)
- Josefine Sprachmann
- Department of Chemistry & IRIS Adlershof, Humboldt University of Berlin, 12489 Berlin, Germany
| | - Tommy Wachsmuth
- Department of Chemistry & IRIS Adlershof, Humboldt University of Berlin, 12489 Berlin, Germany
| | - Manik Bhosale
- Institute of Organic Chemistry II and Advanced Materials, Ulm University, 89081 Ulm, Germany
| | - David Burmeister
- Department of Chemistry & IRIS Adlershof, Humboldt University of Berlin, 12489 Berlin, Germany.,Institut für Physik, Humboldt-Universität zu Berlin, IRIS Adlershof, 12489 Berlin, Germany
| | - Glen J Smales
- Bundesanstalt für Materialforschung und -prüfung (BAM), 12205 Berlin, Germany
| | - Maximilian Schmidt
- Institute of Organic Chemistry II and Advanced Materials, Ulm University, 89081 Ulm, Germany
| | - Zdravko Kochovski
- Department for Electrochemical Energy Storage, Helmholtz-Zentrum Berlin für Materialien und Energie, 14109 Berlin, Germany
| | - Niklas Grabicki
- Department of Chemistry & IRIS Adlershof, Humboldt University of Berlin, 12489 Berlin, Germany
| | - Robin Wessling
- Institute of Organic Chemistry II and Advanced Materials, Ulm University, 89081 Ulm, Germany.,Institute of Organic Chemistry, University of Freiburg, 79104 Freiburg, Germany
| | - Emil J W List-Kratochvil
- Department of Chemistry & IRIS Adlershof, Humboldt University of Berlin, 12489 Berlin, Germany.,Institut für Physik, Humboldt-Universität zu Berlin, IRIS Adlershof, 12489 Berlin, Germany
| | - Birgit Esser
- Institute of Organic Chemistry II and Advanced Materials, Ulm University, 89081 Ulm, Germany
| | - Oliver Dumele
- Department of Chemistry & IRIS Adlershof, Humboldt University of Berlin, 12489 Berlin, Germany
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9
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Abstract
A novel class of stable monoareno-pentalenes is introduced that have an olefinic proton on each five-membered ring of the pentalene subunit. Their synthesis was accomplished via a regioselective carbopalladation cascade reaction between ortho-arylacetyleno gem-dibromoolefins and TIPS-acetylene. These molecules could be experimental probes of magnetic (anti)aromaticity effects.
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Affiliation(s)
- Péter
J. Mayer
- MTA
TTK Lendület Functional Organic Materials Research Group, Institute
of Organic Chemistry, Research Centre for
Natural Sciences, Magyar tudósok krt 2., Budapest, 1117, Hungary,Institute
of Chemistry, University of Szeged, Rerrich tér 1., Szeged, 6720, Hungary
| | - Gábor London
- MTA
TTK Lendület Functional Organic Materials Research Group, Institute
of Organic Chemistry, Research Centre for
Natural Sciences, Magyar tudósok krt 2., Budapest, 1117, Hungary,E-mail:
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10
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Theoretical Study on the Structures, Electronic Properties, and Aromaticity of Thiophene Analogues of Anti-Kekulene. CHEMISTRY 2022. [DOI: 10.3390/chemistry4040102] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022] Open
Abstract
We predict the geometries, electronic properties, and aromaticity of thiophene analogues of anti-kekulene with six to nine thiophene rings 1–4, together with those of cyclobutadithiophenes (CDTs) and anti-kekulene as reference compounds, using density functional theory calculations. Investigation of the simplest reference compounds, CDTs, reveals that the local aromaticity of their thiophene rings is influenced by their fused position (b- or c-bond) to the four-membered ring (4MR). A thiophene ring fused at the b-position (b-TR) retains its aromatic character to some extent, whereas the aromatic character of one fused at the c-position is attenuated. The 4MR with two fused b-TRs retains a strong anti-aromatic character. Thiophene analogues of anti-kekulene with six to eight thiophene rings 1–3 favor bowl-shaped structures, in contrast to the planar structure of anti-kekulene, because of the shorter distances of the sulfur bridges. Compound 4, with nine thiophene rings, adopts a planar structure. The local aromaticity and anti-aromaticity of the thiophene ring and 4MR are significantly attenuated in 1–4 compared with the reference compounds, the CDTs and anti-kekulene. This can be attributed to the considerable contribution of the quinoidal electronic structure in 1–4. The present study provides new insight into the aromatic and electronic nature of systems containing cyclobutadienothiophene.
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11
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Hindenberg P, Belyaev A, Rominger F, Koshevoy IO, Romero-Nieto C. Two-Fold Intramolecular Phosphacyclization: From Fluorescent Diphosphapyrene Salts to Pentavalent Derivatives. Org Lett 2022; 24:6391-6396. [PMID: 36040429 DOI: 10.1021/acs.orglett.2c02391] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
The synthesis of π-extended pyrene-based luminescent compounds containing two six-membered phosphacycles has been realized through a two-step synthesis. It involves a Cu(II)-mediated double cyclization of tertiary diphosphane derivatives to afford dicationic molecules with quaternized phosphorus centers. Subsequent transformation of diphosphonium species into the corresponding P-oxide derivatives has been successfully achieved through Pd(0)-assisted cleavage of the P-Ph bonds, which opens a promising way for the functionalization of polyaromatic P-systems.
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Affiliation(s)
- Philip Hindenberg
- Organisch-Chemisches Institut, Ruprecht-Karls-Universität Heidelberg, Im Neuenheimer Feld 270, 69120 Heidelberg, Germany
| | - Andrey Belyaev
- Department of Chemistry, University of Eastern Finland, Yliopistokatu 7, 80101 Joensuu, Finland
| | - Frank Rominger
- Organisch-Chemisches Institut, Ruprecht-Karls-Universität Heidelberg, Im Neuenheimer Feld 270, 69120 Heidelberg, Germany
| | - Igor O Koshevoy
- Department of Chemistry, University of Eastern Finland, Yliopistokatu 7, 80101 Joensuu, Finland
| | - Carlos Romero-Nieto
- Organisch-Chemisches Institut, Ruprecht-Karls-Universität Heidelberg, Im Neuenheimer Feld 270, 69120 Heidelberg, Germany.,Faculty of Pharmacy, Universidad de Castilla-La Mancha, Calle Almansa 14 - Edif. Bioincubadora, 02008 Albacete, Spain
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12
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Kalapos P, Mayer PJ, Gazdag T, Demeter A, Oruganti B, Durbeej B, London G. Photoswitching of Local (Anti)Aromaticity in Biphenylene-Based Diarylethene Molecular Switches. J Org Chem 2022; 87:9532-9542. [PMID: 35849785 PMCID: PMC9361354 DOI: 10.1021/acs.joc.2c00504] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/04/2022] [Indexed: 02/02/2023]
Abstract
Photoinduced tuning of (anti)aromaticity and associated molecular properties is currently in the focus of attention for both tailoring photochemical reactivity and designing new materials. Here, we report on the synthesis and spectroscopic characterization of diarylethene-based molecular switches embedded in a biphenylene structure composed of rings with different levels of local (anti)aromaticity. We show that it is possible to modulate and control the (anti)aromatic character of each ring through reversible photoswitching of the aryl units of the system between open and closed forms. Remarkably, it is shown that the irreversible formation of an annulated bis(dihydro-thiopyran) side-product that hampers the photoswitching can be efficiently suppressed when the aryl core formed by thienyl groups in one switch is replaced by thiazolyl groups in another.
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Affiliation(s)
- Péter
Pál Kalapos
- MTA
TTK Lendület Functional Organic Materials Research Group, Institute
of Organic Chemistry, Research Centre for
Natural Sciences, Magyar tudósok krt. 2, 1117 Budapest, Hungary
| | - Péter J. Mayer
- MTA
TTK Lendület Functional Organic Materials Research Group, Institute
of Organic Chemistry, Research Centre for
Natural Sciences, Magyar tudósok krt. 2, 1117 Budapest, Hungary
- Institute
of Chemistry, University of Szeged, Rerrich tér 1, 6720 Szeged, Hungary
| | - Tamás Gazdag
- MTA
TTK Lendület Functional Organic Materials Research Group, Institute
of Organic Chemistry, Research Centre for
Natural Sciences, Magyar tudósok krt. 2, 1117 Budapest, Hungary
- Hevesy
György PhD School of Chemistry, Eötvös
Loránd University, Pázmány Péter sétány 1/a, Budapest 1117, Hungary
| | - Attila Demeter
- Institute
of Materials and Environmental Chemistry, Research Centre for Natural Sciences, Magyar tudósok krt. 2, 1117 Budapest, Hungary
| | - Baswanth Oruganti
- Department
of Chemistry and Biomedical Sciences, Faculty of Health and Life Sciences, Linnaeus University, SE-45041 Kalmar, Sweden
| | - Bo Durbeej
- Division
of Theoretical Chemistry, IFM, Linköping
University, SE-58183 Linköping, Sweden
| | - Gábor London
- MTA
TTK Lendület Functional Organic Materials Research Group, Institute
of Organic Chemistry, Research Centre for
Natural Sciences, Magyar tudósok krt. 2, 1117 Budapest, Hungary
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13
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Gazdag T, Mayer PJ, Kalapos PP, Holczbauer T, El Bakouri O, London G. Unsymmetrical Thienopentalenes: Synthesis, Optoelectronic Properties, and (Anti)aromaticity Analysis. ACS OMEGA 2022; 7:8336-8349. [PMID: 35309486 PMCID: PMC8928497 DOI: 10.1021/acsomega.1c05618] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 10/08/2021] [Accepted: 02/22/2022] [Indexed: 06/14/2023]
Abstract
The synthesis and properties of a series of unsymmetrical thienopentalenes are explored, including both monoareno and diareno derivatives. For the synthesis of monoareno pentalenes, a carbopalladation cascade reaction between alkynes and gem-dibromoolefins was applied. Diareno pentalene derivatives were accessed via gold-catalyzed cyclization of diynes. Thiophene was fused to pentalene in two different geometries via its 2,3 and 3,4 bonds. 2,3-Fusion resulted in increased antiaromaticity of the pentalene unit compared to the 3,4-fusion both in the monoareno and diareno framework. Monothienopentalenes that contained the destabilizing 2,3-fusion could not be isolated. For diareno derivatives, the aromatic character of the different aryl groups fused to the pentalene was not independent. Destabilizing fusion on one side resulted in alleviated aromaticity on the other side and vice versa. The synthesized molecules were characterized experimentally by 1H NMR and UV-vis spectroscopies, cyclic voltammetry, and X-ray crystallography, and their aromatic character was assessed using magnetic (NICS and ACID) and electronic indices (MCI and FLU).
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Affiliation(s)
- Tamás Gazdag
- MTA
TTK Lendület Functional Organic Materials Research Group, Institute
of Organic Chemistry, Research Centre for
Natural Sciences, Magyar tudósok krt. 2., Budapest 1117, Hungary
- Hevesy
György PhD School of Chemistry, Eötvös
Loránd University, Pázmány Péter sétány 1/a, Budapest 1117, Hungary
| | - Péter J. Mayer
- MTA
TTK Lendület Functional Organic Materials Research Group, Institute
of Organic Chemistry, Research Centre for
Natural Sciences, Magyar tudósok krt. 2., Budapest 1117, Hungary
- Institute
of Chemistry, University of Szeged, Rerrich tér 1, Szeged 6720, Hungary
| | - Péter Pál Kalapos
- MTA
TTK Lendület Functional Organic Materials Research Group, Institute
of Organic Chemistry, Research Centre for
Natural Sciences, Magyar tudósok krt. 2., Budapest 1117, Hungary
| | - Tamás Holczbauer
- Centre
for Structural Science and Institute of Organic Chemistry, Research Centre for Natural Sciences, Magyar tudósok körútja
2 Budapest 1117, Hungary
| | - Ouissam El Bakouri
- Institut
de Química Computacional i Catàlisi (IQCC) and Departament
de Química, Universitat de Girona, C/Maria Aurèlia Capmany 6, Girona 17003, Catalonia, Spain
| | - Gábor London
- MTA
TTK Lendület Functional Organic Materials Research Group, Institute
of Organic Chemistry, Research Centre for
Natural Sciences, Magyar tudósok krt. 2., Budapest 1117, Hungary
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14
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Horii K, Nogata A, Mizuno Y, Iwasa H, Suzuki M, Nakayama KI, Konishi A, Yasuda M. Synthesis and Characterization of Dinaphtho[2,1-a:2,3-f]pentalene: A Stable Antiaromatic/Quinoidal Hydrocarbon Showing Appropriate Carrier Mobility in the Amorphous Layer. CHEM LETT 2022. [DOI: 10.1246/cl.210809] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
Affiliation(s)
- Koki Horii
- 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
| | - Yusuke Mizuno
- Department of Applied Chemistry, Graduate School of Engineering, Osaka University, 2-1 Yamadaoka, Suita, Osaka 565-0871, Japan
| | - Haruna Iwasa
- 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
| | - Akihito Konishi
- Department of Applied Chemistry, Graduate School of Engineering, Osaka University, 2-1 Yamadaoka, Suita, Osaka 565-0871, Japan
- Center for Atomic and Molecular Technologies, 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
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15
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Hong C, Baltazar J, Tovar JD. Manifestations of antiaromaticity in organic materials: case studies of cyclobutadiene, borole, and pentalene. European J Org Chem 2022. [DOI: 10.1002/ejoc.202101343] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Affiliation(s)
| | | | - John D. Tovar
- Johns Hopkins University Department of Chemistry Department of Materials Science and Engineering 3400 N. Charles StreetNCB 316 MD 21218 Baltimore UNITED STATES
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16
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Saha HK, Mallick D, Das S. Unveiling two antiaromatic s-indacenodicarbazole isomers with tuneable paratropicity. Chem Commun (Camb) 2022; 58:8492-8495. [DOI: 10.1039/d2cc02318k] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Linear and curved antiaromatic s-indacenodicarbazole isomers were synthesized and characterized to show tuneable strength of s-indacene paratropicity, as analyzed by NICS(1)zz and ACID (ring-current) calculations. The curved isomer showed a...
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17
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Usuba J, Fukazawa A. Thiophene-Fused 1,4-Diazapentalene: A Stable C=N-Containing π-Conjugated System with Restored Antiaromaticity. Chemistry 2021; 27:16127-16134. [PMID: 34605567 DOI: 10.1002/chem.202103122] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/31/2021] [Indexed: 11/07/2022]
Abstract
A thiophene-fused 1,4-diazapentalene (TAP) was rationally designed and synthesized as a C=N-containing 4n π-electron system that exhibits restored antiaromaticity impaired by the doping with C=N bonds. X-ray crystallographic analysis and quantum chemical calculations revealed that the annulation of thiophene rings with the 1,4-diazapentalene moiety resulted in a much higher antiaromaticity than the pristine 1,4-diazapentalene. These effects can be ascribed to the reduced bond alternation of the eight-membered-ring periphery caused by stabilization of the less-stable bond-shifted resonance structure upon increasing the degree of substitution of imine moieties. Consequently, TAP underwent facile hydrogenation even under mild conditions because of its pronounced antiaromaticity and the high aromaticity of the corresponding hydrogenated product H2 -TAP. In addition, the electrophilic C=N moieties in TAP led to the formation of a dense π-stacked structure. These results highlight the effect of partial replacement of C=C bonds with C=N bonds in antiaromatic π-electron systems.
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Affiliation(s)
- Junichi Usuba
- Institute for Integrated Cell-Material Sciences (WPI-iCeMS) Institute for Advanced Study, Kyoto University Yoshida, Sakyo-ku, Kyoto, 606-8501, Japan.,Department of Chemistry Graduate School of Science, Nagoya University Furo, Chikusa, Nagoya, 464-8602, Japan
| | - Aiko Fukazawa
- Institute for Integrated Cell-Material Sciences (WPI-iCeMS) Institute for Advanced Study, Kyoto University Yoshida, Sakyo-ku, Kyoto, 606-8501, Japan
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18
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Barker JE, Price TW, Karas LJ, Kishi R, MacMillan SN, Zakharov LN, Gómez-García CJ, Wu JI, Nakano M, Haley MM. A Tale of Two Isomers: Enhanced Antiaromaticity/Diradical Character versus Deleterious Ring-Opening of Benzofuran-fused s-Indacenes and Dicyclopenta[b,g]naphthalenes. Angew Chem Int Ed Engl 2021; 60:22385-22392. [PMID: 34383986 DOI: 10.1002/anie.202107855] [Citation(s) in RCA: 13] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/12/2021] [Indexed: 11/05/2022]
Abstract
We examine the effects of fusing two benzofurans to s-indacene (indacenodibenzofurans, IDBFs) and dicyclopenta[b,g]naphthalene (indenoindenodibenzofurans, IIDBFs) to control the strong antiaromaticity and diradical character of these core units. Synthesis via 3-functionalized benzofuran yields syn-IDBF and syn-IIDBF. syn-IDBF possesses a high degree of paratropicity, exceeding that of the parent hydrocarbon, which in turn results in strong diradical character for syn-IIDBF. In the case of the anti-isomers, synthesized via 2-substituted benzofurans, these effects are decreased; however, both derivatives undergo an unexpected ring-opening reaction during the final dearomatization step. All the results are compared to the benzothiophene-fused analogues and show that the increased electronegativity of oxygen in the syn-fused derivatives leads to enhancement of the antiaromatic core causing greater paratropicity. For syn-IIDBF increased diradical character results from rearomati-zation of the core naphthalene unit in order to relieve this paratropicity.
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Affiliation(s)
- Joshua E Barker
- Department of Chemistry and Biochemistry and the Materials Science Institute, University of Oregon, Eugene, Oregon, 97403-1253, USA
| | - Tavis W Price
- Department of Chemistry and Biochemistry and the Materials Science Institute, University of Oregon, Eugene, Oregon, 97403-1253, USA
| | - Lucas J Karas
- Department of Chemistry, University of Houston, Houston, Texas, 77204, USA
| | - Ryohei Kishi
- Department of Materials Engineering Science, Graduate School of Engineering Science and Center for Quantum Information and Quantum Biology, International Advanced Research Institute (QIQB-IARI), Osaka University, Toyonaka, Osaka, 560-8531, Japan.,Division of Quantum Photochemical Engineering, Research Center for Solar Energy Chemistry (RCSEC), Graduate School of Engineering Science, Osaka University, 1-1 Machikaneyama, Toyonaka, Osaka, 560-0043, Japan
| | - Samantha N MacMillan
- Department of Chemistry & Chemical Biology, Cornell University, Ithaca, New York, 14853, USA
| | - Lev N Zakharov
- Center for Advanced Materials Characterization at Oregon (CAMCOR), University of Oregon, Eugene, Oregon, 97403-1433, USA
| | - Carlos J Gómez-García
- Department of Inorganic Chemistry and Instituto de Ciencia Molecular, Universidad de Valencia, 46980, Paterna, Spain
| | - Judy I Wu
- Department of Chemistry, University of Houston, Houston, Texas, 77204, USA
| | - Masayoshi Nakano
- Department of Materials Engineering Science, Graduate School of Engineering Science and Center for Quantum Information and Quantum Biology, International Advanced Research Institute (QIQB-IARI), Osaka University, Toyonaka, Osaka, 560-8531, Japan.,Division of Quantum Photochemical Engineering, Research Center for Solar Energy Chemistry (RCSEC), Graduate School of Engineering Science, Osaka University, 1-1 Machikaneyama, Toyonaka, Osaka, 560-0043, Japan.,Innovative Catalysis Science Division, Institute for Open and Transdisciplinary Research Initiatives (ICS-OTRI), Osaka University, Suita, Osaka, 565-0871, Japan.,Center for Spintronics Research Network (CSRN), Graduate School of Engineering Science, Osaka University, Toyonaka, Osaka, 560-8531, Japan
| | - Michael M Haley
- Department of Chemistry and Biochemistry and the Materials Science Institute, University of Oregon, Eugene, Oregon, 97403-1253, USA
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19
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Barker JE, Price TW, Karas LJ, Kishi R, MacMillan SN, Zakharov LN, Gómez‐García CJ, Wu JI, Nakano M, Haley MM. A Tale of Two Isomers: Enhanced Antiaromaticity/Diradical Character versus Deleterious Ring‐Opening of Benzofuran‐fused
s
‐Indacenes and Dicyclopenta[
b
,
g
]naphthalenes. Angew Chem Int Ed Engl 2021. [DOI: 10.1002/ange.202107855] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Affiliation(s)
- Joshua E. Barker
- Department of Chemistry and Biochemistry and the Materials Science Institute University of Oregon Eugene Oregon 97403-1253 USA
| | - Tavis W. Price
- Department of Chemistry and Biochemistry and the Materials Science Institute University of Oregon Eugene Oregon 97403-1253 USA
| | - Lucas J. Karas
- Department of Chemistry University of Houston Houston Texas 77204 USA
| | - Ryohei Kishi
- Department of Materials Engineering Science Graduate School of Engineering Science and Center for Quantum Information and Quantum Biology International Advanced Research Institute (QIQB-IARI) Osaka University Toyonaka Osaka 560-8531 Japan
- Division of Quantum Photochemical Engineering Research Center for Solar Energy Chemistry (RCSEC) Graduate School of Engineering Science Osaka University 1-1 Machikaneyama, Toyonaka Osaka 560-0043 Japan
| | - Samantha N. MacMillan
- Department of Chemistry & Chemical Biology Cornell University Ithaca New York 14853 USA
| | - Lev N. Zakharov
- Center for Advanced Materials Characterization at Oregon (CAMCOR) University of Oregon Eugene Oregon 97403-1433 USA
| | - Carlos J. Gómez‐García
- Department of Inorganic Chemistry and Instituto de Ciencia Molecular Universidad de Valencia 46980 Paterna Spain
| | - Judy I. Wu
- Department of Chemistry University of Houston Houston Texas 77204 USA
| | - Masayoshi Nakano
- Department of Materials Engineering Science Graduate School of Engineering Science and Center for Quantum Information and Quantum Biology International Advanced Research Institute (QIQB-IARI) Osaka University Toyonaka Osaka 560-8531 Japan
- Division of Quantum Photochemical Engineering Research Center for Solar Energy Chemistry (RCSEC) Graduate School of Engineering Science Osaka University 1-1 Machikaneyama, Toyonaka Osaka 560-0043 Japan
- Innovative Catalysis Science Division Institute for Open and Transdisciplinary Research Initiatives (ICS-OTRI) Osaka University Suita, Osaka 565-0871 Japan
- Center for Spintronics Research Network (CSRN) Graduate School of Engineering Science Osaka University Toyonaka, Osaka 560-8531 Japan
| | - Michael M. Haley
- Department of Chemistry and Biochemistry and the Materials Science Institute University of Oregon Eugene Oregon 97403-1253 USA
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20
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Warren GI, Barker JE, Zakharov LN, Haley MM. Enhancing the Antiaromaticity of s-Indacene through Naphthothiophene Fusion. Org Lett 2021; 23:5012-5017. [PMID: 34129339 DOI: 10.1021/acs.orglett.1c01514] [Citation(s) in RCA: 14] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
Addressing the instability of antiaromatic compounds often involves protection with bulky groups and/or fusion of aromatic rings, thus decreasing paratropicity. We report four naphthothiophene-fused s-indacene isomers, one of which is more antiaromatic than parent s-indacene. This surprising result is examined computationally through nucleus-independent chemical shift XY calculations and experimentally via nuclear magnetic resonance spectroscopy, X-ray crystallography, ultraviolet-visible spectrophotometry, and cyclic voltammetry, with the latter two indicating that this molecule possesses the lowest highest occupied molecular orbital-lowest unoccupied molecular orbital energy gap observed for heterocycle-fused s-indacene.
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Affiliation(s)
- Gabrielle I Warren
- Department of Chemistry & Biochemistry, University of Oregon, Eugene, Oregon 97403, United States
| | - Joshua E Barker
- Department of Chemistry & Biochemistry, University of Oregon, Eugene, Oregon 97403, United States
| | - Lev N Zakharov
- CAMCOR, University of Oregon, Eugene, Oregon 97403, United States
| | - Michael M Haley
- Department of Chemistry & Biochemistry, University of Oregon, Eugene, Oregon 97403, United States
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21
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Chen M, Sato W, Shang R, Nakamura E. Iron-Catalyzed Tandem Cyclization of Diarylacetylene to a Strained 1,4-Dihydropentalene Framework for Narrow-Band-Gap Materials. J Am Chem Soc 2021; 143:6823-6828. [PMID: 33929185 DOI: 10.1021/jacs.1c03394] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
Carbon bridging in a form of a strained 1,4-dihydropentalene framework is an effective strategy for flattening and stabilizing oligophenylenevinylene systems for the development of optoelectronic materials. However, efficient and flexible methods for making such a strained ring system are lacking. We report herein a mild and versatile synthetic access to the 1,4-dihydropentalene framework enabled by iron-catalyzed single-pot tandem cyclization of a diarylacetylene using FeCl2 and PPh3 as catalyst, magnesium/LiCl as a reductant, and 1,2-dichloropropane as a mild oxidant. The new annulation method features two iron-catalyzed transformations used in tandem, a reductive acetylenic carboferration and an oxidation-induced ring contraction of a ferracycle under mild oxidative conditions. The new method provides access not only to a variety of substituted indeno[2,1-a]indenes but also to their thiophene congeners, 4,9-dihydrobenzo[4,5]pentaleno[1,2-b]thiophene (CPTV) and 4,8-dihydropentaleno[1,2-b:4,5-b']dithiophenes (CTV). With its high highest occupied molecular orbital level and narrow optical gap, CTV serves as a donor unit in a narrow-band-gap non-fullerene acceptor, which shows absorption extending over 1000 nm in the film state, and has found use in a near-infrared photodetector device that exhibited an external quantum efficiency of 72.4% at 940 nm.
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Affiliation(s)
- Mengqing Chen
- Department of Chemistry, The University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo 113-0033, Japan
| | - Wataru Sato
- Department of Chemistry, The University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo 113-0033, Japan
| | - Rui Shang
- Department of Chemistry, The University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo 113-0033, Japan
| | - Eiichi Nakamura
- Department of Chemistry, The University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo 113-0033, Japan
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22
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Konishi A, Yasuda M. Breathing New Life into Nonalternant Hydrocarbon Chemistry: Syntheses and Properties of Polycyclic Hydrocarbons Containing Azulene, Pentalene, and Heptalene Frameworks. CHEM LETT 2021. [DOI: 10.1246/cl.200650] [Citation(s) in RCA: 31] [Impact Index Per Article: 10.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Affiliation(s)
- Akihito Konishi
- Department of Applied Chemistry, Graduate School of Engineering, Osaka University, 2-1 Yamadaoka, Suita, Osaka 565-0871, Japan
- Center for Atomic and Molecular Technologies, Graduate School of Engineering, Osaka University, 2-1 Yamadaoka, 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
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23
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Phenanthrylene–alkynylene macrocycles, phenanthrene-fused dicyclopenta[b,g]naphthalene, as well as relevant diradicaloids and antiaromatic compounds. ADVANCES IN PHYSICAL ORGANIC CHEMISTRY 2021. [DOI: 10.1016/bs.apoc.2021.09.001] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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