1
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Wang J, Gámez FG, Marín-Beloqui J, Diaz-Andres A, Miao X, Casanova D, Casado J, Liu J. Synthesis of a Dicyclohepta[a,g]heptalene-Containing Polycyclic Conjugated Hydrocarbon and the Impact of Non-Alternant Topologies. Angew Chem Int Ed Engl 2023; 62:e202217124. [PMID: 36511094 DOI: 10.1002/anie.202217124] [Citation(s) in RCA: 14] [Impact Index Per Article: 14.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/21/2022] [Revised: 12/12/2022] [Accepted: 12/13/2022] [Indexed: 12/15/2022]
Abstract
Incorporating non-hexagonal rings into polycyclic conjugated hydrocarbons (PCHs) can significantly affect their electronic and optoelectronic properties and chemical reactivities. Here, we report the first bottom-up synthesis of a dicyclohepta[a,g]heptalene-embedded PCH (1) with four continuous heptagons, which are arranged in a "Z" shape. Compared with its structural isomer bischrysene 1 R with only hexagonal rings, compound 1 presents a distinct antiaromatic character, especially the inner heptalene core, which possesses clear antiaromatic nature. In addition, PCH 1 exhibits a narrower highest occupied molecular orbital (HOMO)-lowest unoccupied molecular orbital (LUMO) energy gap than its benzenoid contrast 1 R, as verified by experimental measurements and theoretical calculations. Our work reported herein not only provides a new way to synthesize novel PCHs with non-alternant topologies but also offers the possibility to tune their electronic and optical properties.
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Affiliation(s)
- Junting Wang
- Department of Chemistry and State Key Laboratory of Synthetic Chemistry, The University of Hong Kong, Pokfulam Road, Hong Kong, China
| | - Fernando Gordillo Gámez
- Department of Physical Chemistry, University of Malaga, Campus de Teations s/n, 229071, Malaga, Spain
| | - Jose Marín-Beloqui
- Department of Physical Chemistry, University of Malaga, Campus de Teations s/n, 229071, Malaga, Spain
| | - Aitor Diaz-Andres
- Donostia International Physics Center (DIPC), 20018, Donostia, Euskadi, Spain
| | - Xiaohe Miao
- Instrumentation and Service Center for Physical Sciences, Westlake University, Hangzhou, 310024, Zhejiang Province, China
| | - David Casanova
- Donostia International Physics Center (DIPC), 20018, Donostia, Euskadi, Spain.,IKERBASQUE-Basque Foundation for Science, 48009, Bilbao, Euskadi, Spain
| | - Juan Casado
- Department of Physical Chemistry, University of Malaga, Campus de Teations s/n, 229071, Malaga, Spain
| | - Junzhi Liu
- Department of Chemistry and State Key Laboratory of Synthetic Chemistry, The University of Hong Kong, Pokfulam Road, Hong Kong, China
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2
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Hung TY, Kuck D, Chow HF. Donor-Acceptor Tribenzotriquinacene-Based Molecular Wizard Hats Bearing Three ortho-Benzoquinone Units. Chemistry 2022; 29:e202203749. [PMID: 36585931 DOI: 10.1002/chem.202203749] [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: 11/30/2022] [Revised: 12/29/2022] [Accepted: 12/29/2022] [Indexed: 01/01/2023]
Abstract
Two π-extended bay-bridged tribenzotriquinacenes ("TBTQ wizard hats") 12 and 16 bearing three mutually conjugated, alternating veratrole-type and ortho-benzoquinone units were synthesized. The electronic properties of these complementarily arranged, nonplanar push-pull systems are affected by the fusion with the rigid, C3 -symmetric TBTQ core to a different extent, as revealed by X-ray structural analysis, UV-vis spectroscopy and cyclovoltammetry. The combination of three quinone units within the original TBTQ core and three veratrole-type bay bridging units in 12 gives rise to a more efficiently π-conjugated chromophore, as reflected by the shallower shape of wizard hat and its absorption in the visible up to 750 nm in comparison to 16. Congener 12 contains an aromatic 18-π electron system in contrast to the cross-conjugated analog 16. X-ray structure analysis of the precursor dodecaether 15 revealed the formation of a cage-like supramolecular dimer, in which the peripheral dioxane-type ether groups interlace by twelve noncovalent C-H⋅⋅⋅⋅⋅O bonds.
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Affiliation(s)
- Tsz-Yu Hung
- Department of Chemistry, The Chinese University of Hong Kong, Shatin, Hong Kong
| | - Dietmar Kuck
- Department of Chemistry, Bielefeld University, Universitätsstraße 25, 33615, Bielefeld, Germany
| | - Hak-Fun Chow
- Department of Chemistry, The Chinese University of Hong Kong, Shatin, Hong Kong
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3
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Qiu ZL, Chen XW, Huang YD, Wei RJ, Chu KS, Zhao XJ, Tan YZ. Nanographene with Multiple Embedded Heptagons: Cascade Radical Photocyclization. Angew Chem Int Ed Engl 2022; 61:e202116955. [PMID: 35191583 DOI: 10.1002/anie.202116955] [Citation(s) in RCA: 12] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/12/2021] [Indexed: 12/27/2022]
Abstract
Although heptagons are widely found in graphenic materials, the precise synthesis of nanocarbons containing heptagons remains a challenge, especially for the nanocarbons containing multiple-heptagons. Herein, we show that photo-induced radical cyclization (PIRC) can be used to synthesize multi-heptagon-embedded nanocarbons. Notably, a nanographene containing six heptagons (1) was obtained via a six-fold cascade PIRC reaction. The structure of 1 was clearly validated and showed a Monkey-saddle-shaped conformation. Experimental bond analysis and theoretical calculations indicated that the heptagons in 1 were non-aromatic, whereas the peripheral rings were highly aromatic. Compared to planar nanographene with the same number of π electrons, 1 had a similar optical gap due to a compromise between the decreased conjugation in the wrapped structure and enhanced electronic delocalization at the rim. Electrochemical studies showed that 1 had low-lying oxidation potentials, which was attributed to the nitrogen-doping.
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Affiliation(s)
- Zhen-Lin Qiu
- State Key Laboratory for Physical Chemistry of Solid Surfaces, Department of Chemistry, College of Chemistry, Chemical Engineering, Xiamen University, Xiamen, 361005, China
| | - Xuan-Wen Chen
- State Key Laboratory for Physical Chemistry of Solid Surfaces, Department of Chemistry, College of Chemistry, Chemical Engineering, Xiamen University, Xiamen, 361005, China
| | - Yu-Dong Huang
- State Key Laboratory for Physical Chemistry of Solid Surfaces, Department of Chemistry, College of Chemistry, Chemical Engineering, Xiamen University, Xiamen, 361005, China
| | - Rong-Jing Wei
- State Key Laboratory for Physical Chemistry of Solid Surfaces, Department of Chemistry, College of Chemistry, Chemical Engineering, Xiamen University, Xiamen, 361005, China
| | - Ke-Shan Chu
- State Key Laboratory for Physical Chemistry of Solid Surfaces, Department of Chemistry, College of Chemistry, Chemical Engineering, Xiamen University, Xiamen, 361005, China
| | - Xin-Jing Zhao
- State Key Laboratory for Physical Chemistry of Solid Surfaces, Department of Chemistry, College of Chemistry, Chemical Engineering, Xiamen University, Xiamen, 361005, China
| | - Yuan-Zhi Tan
- State Key Laboratory for Physical Chemistry of Solid Surfaces, Department of Chemistry, College of Chemistry, Chemical Engineering, Xiamen University, Xiamen, 361005, China
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4
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Qiu Z, Chen X, Huang Y, Wei R, Chu K, Zhao X, Tan Y. Nanographene with Multiple Embedded Heptagons: Cascade Radical Photocyclization. Angew Chem Int Ed Engl 2022. [DOI: 10.1002/ange.202116955] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
Affiliation(s)
- Zhen‐Lin Qiu
- State Key Laboratory for Physical Chemistry of Solid Surfaces Department of Chemistry College of Chemistry Chemical Engineering Xiamen University Xiamen 361005 China
| | - Xuan‐Wen Chen
- State Key Laboratory for Physical Chemistry of Solid Surfaces Department of Chemistry College of Chemistry Chemical Engineering Xiamen University Xiamen 361005 China
| | - Yu‐Dong Huang
- State Key Laboratory for Physical Chemistry of Solid Surfaces Department of Chemistry College of Chemistry Chemical Engineering Xiamen University Xiamen 361005 China
| | - Rong‐Jing Wei
- State Key Laboratory for Physical Chemistry of Solid Surfaces Department of Chemistry College of Chemistry Chemical Engineering Xiamen University Xiamen 361005 China
| | - Ke‐Shan Chu
- State Key Laboratory for Physical Chemistry of Solid Surfaces Department of Chemistry College of Chemistry Chemical Engineering Xiamen University Xiamen 361005 China
| | - Xin‐Jing Zhao
- State Key Laboratory for Physical Chemistry of Solid Surfaces Department of Chemistry College of Chemistry Chemical Engineering Xiamen University Xiamen 361005 China
| | - Yuan‐Zhi Tan
- State Key Laboratory for Physical Chemistry of Solid Surfaces Department of Chemistry College of Chemistry Chemical Engineering Xiamen University Xiamen 361005 China
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5
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Sekiya R, Haino T. Nanographene - A Scaffold of Two-Dimensional Materials. CHEM REC 2021; 22:e202100257. [PMID: 34962042 DOI: 10.1002/tcr.202100257] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/03/2021] [Revised: 12/03/2021] [Indexed: 11/07/2022]
Abstract
Substances can be divided into 0D to 3D species based on the number of repeating units (atom, ion, and molecule) and their arrangements in space (point, linear, layer, and solid). Discrete substances belong to 0D species, polymers are examples of 1D species, and molecular crystals are 3D species. Most of the substances belong to one of these species. On the other hand, those categorized into 2D species wherein the repeating units organize a layer are less explored. 2D species have a surface and edges. The incorporation of these structural features into a molecular design can realize multifunctionalized systems that are difficult to achieve by conventional organic synthesis. The development of 2D species is, therefore, the frontier of organic, inorganic, and polymer chemistry. Nanographenes (NGs) are suitable scaffolds for realizing 2D species due to several factors, such as chemical stability and oxygen-containing functional groups on the surface and on the edge, allowing postsynthetic modifications. Our group has utilized NGs with tens of nanometers in diameters for developing 2D species. Carboxy groups on the edge enable us to install various substituents into NGs, offering NG-based functional materials. These studies demonstrate that the integration of NGs with organic chemistry can widen the scope of their applications other than optical materials that are a main application of NGs. We introduce our recent studies on the development of NG-based functional materials realized by postsynthetic modifications. We hope that this account will contribute to the development of the chemistry of 2D species.
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Affiliation(s)
- Ryo Sekiya
- Department of Chemistry, Graduate School of Advanced Science and Engineering, Hiroshima University, 1-3-1 Kagamiyama, Higashi-Hiroshima, Hiroshima, 739-8526, Japan
| | - Takeharu Haino
- Department of Chemistry, Graduate School of Advanced Science and Engineering, Hiroshima University, 1-3-1 Kagamiyama, Higashi-Hiroshima, Hiroshima, 739-8526, Japan
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6
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Li R, Ma B, He RY, Zhang B, Zhang YK, Feng SY, An P. Azepine- or Oxepine-embedded Double Saddle-Helix Nanographenes. Chem Asian J 2021; 17:e202101365. [PMID: 34904381 DOI: 10.1002/asia.202101365] [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: 12/08/2021] [Indexed: 11/09/2022]
Abstract
The azepine- and oxepine-embedded polycyclic aromatic hydrocarbons (PAH) 1-3, as the hexa-peri-hexabenzocoronene (HBC)-based nanographenes (NG) were designed and synthesized by Diels-Alder reaction of cyclic alkene with tetrachlorothiophene-S,S-dioxide, followed by Suzuki-Miyaura cross-coupling and Scholl-type cyclodehydrogenation. Due to the strained seven-membered ring and the inherent structural pattern, heteroatom-doped NGs 1-3 show Cs symmetrical, double saddle-helix hybrid conformation, which represents a new shape for HBC based nanographenes. The calculation studies reveal the low aromaticity of the 8π heterocycles themselves and the heterocycles also decrease the electron delocalization of benzenes surrounding them. Dynamics-based calculation suggests the Cs symmetry would maintain druing the saddle-inversion process. Meanwhile, we show property perturbation by doping with different heteroatoms.
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Affiliation(s)
- Ranran Li
- School of Chemical Science and Technology, Ynunan University, Kunming, 650500, P. R. China
| | - Bin Ma
- School of Chemical Science and Technology, Ynunan University, Kunming, 650500, P. R. China
| | - Run-Ying He
- School of Chemical Science and Technology, Ynunan University, Kunming, 650500, P. R. China
| | - Bin Zhang
- School of Chemical Science and Technology, Ynunan University, Kunming, 650500, P. R. China
| | - Yi-Kang Zhang
- School of Chemical Science and Technology, Ynunan University, Kunming, 650500, P. R. China
| | - Shi-Yu Feng
- School of Chemical Science and Technology, Ynunan University, Kunming, 650500, P. R. China
| | - Peng An
- School of Chemical Science and Technology, Ynunan University, Kunming, 650500, P. R. China
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7
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Ejlli B, Nußbaum P, Rominger F, Freudenberg J, Bunz UHF, Müllen K. Benzo‐fused Tri[8]annulenes as Molecular Models of Cubic Graphite. Angew Chem Int Ed Engl 2021. [DOI: 10.1002/ange.202106233] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Affiliation(s)
- Barbara Ejlli
- Organisch-Chemisches Institut Ruprecht-Karls-Universität Heidelberg Im Neuenheimer Feld 270 69120 Heidelberg Germany
- InnovationLab Speyerer Str. 4 69115 Heidelberg Germany
- Max Planck Institute for Polymer Research Ackermannweg 10 55128 Mainz Germany
| | - Pascal Nußbaum
- Organisch-Chemisches Institut Ruprecht-Karls-Universität Heidelberg Im Neuenheimer Feld 270 69120 Heidelberg Germany
| | - Frank Rominger
- Organisch-Chemisches Institut Ruprecht-Karls-Universität Heidelberg Im Neuenheimer Feld 270 69120 Heidelberg Germany
| | - Jan Freudenberg
- Organisch-Chemisches Institut Ruprecht-Karls-Universität Heidelberg Im Neuenheimer Feld 270 69120 Heidelberg Germany
- InnovationLab Speyerer Str. 4 69115 Heidelberg Germany
| | - Uwe H. F. Bunz
- Organisch-Chemisches Institut Ruprecht-Karls-Universität Heidelberg Im Neuenheimer Feld 270 69120 Heidelberg Germany
| | - Klaus Müllen
- Max Planck Institute for Polymer Research Ackermannweg 10 55128 Mainz Germany
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8
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Yang X, Rominger F, Mastalerz M. Contorted Heteroannulated Tetraareno[a,d,j,m]coronenes. Chemistry 2021; 27:14345-14352. [PMID: 34374459 PMCID: PMC8596641 DOI: 10.1002/chem.202102112] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/14/2021] [Indexed: 11/06/2022]
Abstract
Fused polycyclic aromatic compounds are interesting materials for organic electronics applications. To fine-tune photophysical or electrochemical properties, either various substituents can be attached or heteroatoms (such as N or S) can be incorporated into the fused aromatic backbone. Coronenes and heterocoronenes are promising compounds in this respect. Up until now, the possibilities for varying the attached fused heteroaromatics at the coronene core were quite limited, and realizing both electron-withdrawing and -donating rings at the same time was very difficult. Here, a series of pyridine, anisole and thiophene annulated tetraareno[a,d,j,m]coronenes has been synthesized by a facile two-step route that is a combination of Suzuki-Miyaura cross-coupling and a following cyclization step, starting from three different diarenoperylene dibromides. The contorted molecular π-planes of the obtained cata-condensed tetraarenocoronenes were analyzed by single-crystal X-ray crystallography, and the photophysical and electrochemical properties were systematically investigated by UV/Vis spectroscopy and cyclovoltammetry.
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Affiliation(s)
- Xuan Yang
- Organisch-Chemisches Institut, Ruprecht-Karls-Universität Heidelberg, Im Neuenheimer Feld 270, 69120, Heidelberg, Germany
| | - Frank Rominger
- Organisch-Chemisches Institut, Ruprecht-Karls-Universität Heidelberg, Im Neuenheimer Feld 270, 69120, Heidelberg, Germany
| | - Michael Mastalerz
- Organisch-Chemisches Institut, Ruprecht-Karls-Universität Heidelberg, Im Neuenheimer Feld 270, 69120, Heidelberg, Germany
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9
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Ejlli B, Nußbaum P, Rominger F, Freudenberg J, Bunz UHF, Müllen K. Benzo-fused Tri[8]annulenes as Molecular Models of Cubic Graphite. Angew Chem Int Ed Engl 2021; 60:20220-20224. [PMID: 34156743 PMCID: PMC8457115 DOI: 10.1002/anie.202106233] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/08/2021] [Revised: 06/11/2021] [Indexed: 12/18/2022]
Abstract
Cyclotrimerization of 9,10‐dibromo‐9,10‐dihydrodibenzo[3,4:7,8]cycloocta[1,2‐l]phenanthrene with potassium tert‐butoxide in the presence of a transition‐metal catalyst afforded two polycyclic aromatic hydrocarbon stereoisomers consisting of three cyclooctatetraene (COT) moieties connected via a central benzene ring. Both isomeric tri[8]annulenes were obtained selectively through the choice of the catalyst: The α,α,α‐form (Ru catalyst) displayed a threefold symmetrywith the COT subunits forming the side walls of a (chiral) molecular cup. In the thermodynamically more stable α,α,β‐isomer (Pd catalyst), one of the three boat‐shaped COTs was flipped over and faced the opposite molecular hemisphere with respect to the central benzene ring as evidenced by crystal structure analysis. Both title compounds are small segments of “cubic graphite”, an elusive carbon allotrope.
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Affiliation(s)
- Barbara Ejlli
- Organisch-Chemisches Institut, Ruprecht-Karls-Universität Heidelberg, Im Neuenheimer Feld 270, 69120, Heidelberg, Germany.,InnovationLab, Speyerer Str. 4, 69115, Heidelberg, Germany.,Max Planck Institute for Polymer Research, Ackermannweg 10, 55128, Mainz, Germany
| | - Pascal Nußbaum
- Organisch-Chemisches Institut, Ruprecht-Karls-Universität Heidelberg, Im Neuenheimer Feld 270, 69120, Heidelberg, Germany
| | - Frank Rominger
- Organisch-Chemisches Institut, Ruprecht-Karls-Universität Heidelberg, Im Neuenheimer Feld 270, 69120, Heidelberg, Germany
| | - Jan Freudenberg
- Organisch-Chemisches Institut, Ruprecht-Karls-Universität Heidelberg, Im Neuenheimer Feld 270, 69120, Heidelberg, Germany.,InnovationLab, Speyerer Str. 4, 69115, Heidelberg, Germany
| | - Uwe H F Bunz
- Organisch-Chemisches Institut, Ruprecht-Karls-Universität Heidelberg, Im Neuenheimer Feld 270, 69120, Heidelberg, Germany
| | - Klaus Müllen
- Max Planck Institute for Polymer Research, Ackermannweg 10, 55128, Mainz, Germany
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10
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Wang Y, Zhang Y, Wang S, Cao D. Saddle-Shaped Building Blocks: A New Concept for Designing Fully Conjugated 3D Organic Semiconducting Materials. Chemistry 2021; 27:12012-12018. [PMID: 34042231 DOI: 10.1002/chem.202101326] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/13/2021] [Indexed: 12/14/2022]
Abstract
Currently, most organic semiconducting materials (OSMs) are π-conjugated structures in one or two dimension (2D), where the lack of layer-layer π-conjugation connection greatly blocks their electron delocalization and transport. The 3D fully conjugated materials could solve this issue because they can provide efficient charge-transport pathways throughout the whole 3D skeleton, in which the suitable 3D building block is the key to the development of fully conjugated 3D OSMs. Cyclooctatetraene (COT) and its derivatives are good candidates due to their π-conjugation with 3D saddle-shaped architecture. In this Concept, we discuss the key features of saddle-shaped COT-based derivatives and their synthetic strategy, then we present the current development of using the COT derivatives as building blocks to construct the 3D fully conjugated organic small compound- and polymer-based OSMs. The properties and perspectives of these OSMs in photovoltaics, electro-catalysis and electrical conductivities are also discussed. These recent advances in the developing 3D fully conjugated materials could potentially open up a new frontier in the design of OSMs.
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Affiliation(s)
- Yaqin Wang
- State Key Laboratory of Organic-Inorganic Composites, Beijing University of Chemical Technology, Beijing, 100029, P. R. China
| | - Yuting Zhang
- State Key Laboratory of Organic-Inorganic Composites, Beijing University of Chemical Technology, Beijing, 100029, P. R. China
| | - Shitao Wang
- State Key Laboratory of Organic-Inorganic Composites, Beijing University of Chemical Technology, Beijing, 100029, P. R. China
| | - Dapeng Cao
- State Key Laboratory of Organic-Inorganic Composites, Beijing University of Chemical Technology, Beijing, 100029, P. R. China
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11
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Full J, Panchal SP, Götz J, Krause A, Nowak‐Król A. Modular Synthesis of Organoboron Helically Chiral Compounds: Cutouts from Extended Helices. Angew Chem Int Ed Engl 2021; 60:4350-4357. [PMID: 33244880 PMCID: PMC7898935 DOI: 10.1002/anie.202014138] [Citation(s) in RCA: 56] [Impact Index Per Article: 18.7] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/21/2020] [Revised: 11/25/2020] [Indexed: 11/12/2022]
Abstract
Two types of helically chiral compounds bearing one and two boron atoms were synthesized by a modular approach. Formation of the helical scaffolds was executed by the introduction of boron to flexible biaryl and triaryl derived from small achiral building blocks. All-ortho-fused azabora[7]helicenes feature exceptional configurational stability, blue or green fluorescence with quantum yields (Φfl ) of 18-24 % in solution, green or yellow solid-state emission (Φfl up to 23 %), and strong chiroptical response with large dissymmetry factors of up to 1.12×10-2 . Azabora[9]helicenes consisting of angularly and linearly fused rings are blue emitters exhibiting Φfl of up to 47 % in CH2 Cl2 and 25 % in the solid state. As revealed by the DFT calculations, their P-M interconversion pathway is more complex than that of H1. Single-crystal X-ray analysis shows clear differences in the packing arrangement of methyl and phenyl derivatives. These molecules are proposed as primary structures of extended helices.
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Affiliation(s)
- Julian Full
- Institut für Anorganische ChemieUniversität WürzburgAm Hubland97074WürzburgGermany
- Institut für Organische Chemie and Center for Nanosystems ChemistryUniversität WürzburgAm Hubland97074WürzburgGermany
| | - Santosh P. Panchal
- Institut für Anorganische ChemieUniversität WürzburgAm Hubland97074WürzburgGermany
- Institut für Organische Chemie and Center for Nanosystems ChemistryUniversität WürzburgAm Hubland97074WürzburgGermany
| | - Julian Götz
- Institut für Organische Chemie and Center for Nanosystems ChemistryUniversität WürzburgAm Hubland97074WürzburgGermany
| | - Ana‐Maria Krause
- Institut für Organische Chemie and Center for Nanosystems ChemistryUniversität WürzburgAm Hubland97074WürzburgGermany
| | - Agnieszka Nowak‐Król
- Institut für Anorganische ChemieUniversität WürzburgAm Hubland97074WürzburgGermany
- Institut für Organische Chemie and Center for Nanosystems ChemistryUniversität WürzburgAm Hubland97074WürzburgGermany
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12
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Zhou Z, Zhu Y, Wei Z, Bergner J, Neiß C, Doloczki S, Görling A, Kivala M, Petrukhina MA. Reduction of π-Expanded Cyclooctatetraene with Lithium: Stabilization of the Tetra-Anion through Internal Li + Coordination. Angew Chem Int Ed Engl 2021; 60:3510-3514. [PMID: 33108043 PMCID: PMC7898929 DOI: 10.1002/anie.202013353] [Citation(s) in RCA: 13] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/03/2020] [Indexed: 01/18/2023]
Abstract
The chemical reduction of a π-expanded polycyclic framework comprising a cyclooctatetraene moiety, octaphenyltetrabenzocyclooctatetraene, with lithium metal readily affords the corresponding tetra-anion instead of the expected aromatic dianion. As revealed by X-ray crystallography, the highly contorted tetra-anion is stabilized by coordination of two internally bound Li+ , while two external cations remain solvent separated. The variable-temperature 7 Li NMR spectra in THF confirm the presence of three types of Li+ ions and clearly differentiate internal binding, consistent with the crystal structure. Density-functional theory calculations suggest that the formation of the highly charged tetra-reduced carbanion is stabilized through Li+ coordination under the applied experimental conditions.
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Affiliation(s)
- Zheng Zhou
- Department of ChemistryUniversity at AlbanyState University of New York1400 Washington Ave.AlbanyNY12222USA
| | - Yikun Zhu
- Department of ChemistryUniversity at AlbanyState University of New York1400 Washington Ave.AlbanyNY12222USA
| | - Zheng Wei
- Department of ChemistryUniversity at AlbanyState University of New York1400 Washington Ave.AlbanyNY12222USA
| | - John Bergner
- Organisch-Chemisches InstitutRuprecht-Karls-Universität HeidelbergIm Neuenheimer Feld 27069120HeidelbergGermany
- Centre for Advanced MaterialsRuprecht-Karls-Universität HeidelbergIm Neuenheimer Feld 22569120HeidelbergGermany
| | - Christian Neiß
- Department of Chemistry and PharmacyChair of Theoretical ChemistryFriedrich-Alexander-Universität Erlangen-NürnbergEgerlandstr. 391058ErlangenGermany
| | - Susanne Doloczki
- Department of Chemistry and PharmacyChair of Organic Chemistry IFriedrich-Alexander-Universität Erlangen-NürnbergNikolaus-Fiebiger-Str. 1091058ErlangenGermany
| | - Andreas Görling
- Department of Chemistry and PharmacyChair of Theoretical ChemistryFriedrich-Alexander-Universität Erlangen-NürnbergEgerlandstr. 391058ErlangenGermany
| | - Milan Kivala
- Organisch-Chemisches InstitutRuprecht-Karls-Universität HeidelbergIm Neuenheimer Feld 27069120HeidelbergGermany
- Centre for Advanced MaterialsRuprecht-Karls-Universität HeidelbergIm Neuenheimer Feld 22569120HeidelbergGermany
| | - Marina A. Petrukhina
- Department of ChemistryUniversity at AlbanyState University of New York1400 Washington Ave.AlbanyNY12222USA
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13
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Medel MA, Tapia R, Blanco V, Miguel D, Morcillo SP, Campaña AG. Octagon-Embedded Carbohelicene as a Chiral Motif for Circularly Polarized Luminescence Emission of Saddle-Helix Nanographenes. Angew Chem Int Ed Engl 2021; 60:6094-6100. [PMID: 33337575 DOI: 10.1002/anie.202015368] [Citation(s) in RCA: 52] [Impact Index Per Article: 17.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/17/2020] [Indexed: 12/17/2022]
Abstract
We report a new family of hexa-peri-hexabenzocoronene (HBC)-based helical nanographenes incorporating π-extended carbo[5]helicenes bearing an octagonal carbocycle. This family represents a new kind of highly distorted saddle-helix hybrid nanographenes. For the first time, the eight-membered ring becomes a constituent of both a carbo[5]helicene and a HBC and thus, the negative curvature is responsible for twisting both units. This novel chiral motif, namely, oct-[5]helicene results in the largest torsion angle recorded so far for a carbo[5]helicene (θ=79.5°), as it has been suggested by DFT-calculations and confirmed by X-ray crystallography. Consequently, the barriers of isomerization become exceptionally high for a [5]helicene unsubstituted in the fjord region since neither racemization nor decomposition were observed at 200 °C for 1 or 3 during 5 h. Therefore, racemic resolutions allowed subsequent chiroptical studies showing the ECD and CPL responses of this novel family of chiral nanographenes.
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Affiliation(s)
- Miguel A Medel
- Departamento de Química Orgánica, Unidad de Excelencia de Química (UEQ), Facultad de Ciencias, Universidad de Granada, 18071, Granada, Spain
| | - Rubén Tapia
- Departamento de Química Orgánica, Unidad de Excelencia de Química (UEQ), Facultad de Ciencias, Universidad de Granada, 18071, Granada, Spain
| | - Victor Blanco
- Departamento de Química Orgánica, Unidad de Excelencia de Química (UEQ), Facultad de Ciencias, Universidad de Granada, 18071, Granada, Spain
| | - Delia Miguel
- Departamento de Fisicoquímica, Facultad de Farmacia, UEQ, Universidad de Granada, Granada, Spain
| | - Sara P Morcillo
- Departamento de Química Orgánica, Unidad de Excelencia de Química (UEQ), Facultad de Ciencias, Universidad de Granada, 18071, Granada, Spain
| | - Araceli G Campaña
- Departamento de Química Orgánica, Unidad de Excelencia de Química (UEQ), Facultad de Ciencias, Universidad de Granada, 18071, Granada, Spain
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14
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Medel MA, Tapia R, Blanco V, Miguel D, Morcillo SP, Campaña AG. Octagon‐Embedded Carbohelicene as a Chiral Motif for Circularly Polarized Luminescence Emission of Saddle‐Helix Nanographenes. Angew Chem Int Ed Engl 2021. [DOI: 10.1002/ange.202015368] [Citation(s) in RCA: 16] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022]
Affiliation(s)
- Miguel A. Medel
- Departamento de Química Orgánica Unidad de Excelencia de Química (UEQ) Facultad de Ciencias Universidad de Granada 18071 Granada Spain
| | - Rubén Tapia
- Departamento de Química Orgánica Unidad de Excelencia de Química (UEQ) Facultad de Ciencias Universidad de Granada 18071 Granada Spain
| | - Victor Blanco
- Departamento de Química Orgánica Unidad de Excelencia de Química (UEQ) Facultad de Ciencias Universidad de Granada 18071 Granada Spain
| | - Delia Miguel
- Departamento de Fisicoquímica Facultad de Farmacia, UEQ Universidad de Granada Granada Spain
| | - Sara P. Morcillo
- Departamento de Química Orgánica Unidad de Excelencia de Química (UEQ) Facultad de Ciencias Universidad de Granada 18071 Granada Spain
| | - Araceli G. Campaña
- Departamento de Química Orgánica Unidad de Excelencia de Química (UEQ) Facultad de Ciencias Universidad de Granada 18071 Granada Spain
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15
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Ueberricke L, Punja Benke B, Kirschbaum T, Hahn S, Rominger F, Bunz UHF, Mastalerz M. Synthesis and Optoelectronic Properties of a Quinoxalino-Phenanthrophenazine (QPP) Extended Tribenzotriquinacene (TBTQ). Chemistry 2021; 27:2043-2049. [PMID: 32954544 PMCID: PMC7898691 DOI: 10.1002/chem.202003666] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/07/2020] [Indexed: 12/21/2022]
Abstract
A six‐step synthesis towards a tribenzotriquinacene (TBTQ) bearing three quinoxalinophenanthrophenazine (QPP) units is presented. The optoelectronic properties are investigated and the effect of the three‐dimensional arrangement of the individual QPP planes is examined using optical spectroscopy, electrochemical analysis and quantum‐chemical calculations.
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Affiliation(s)
- Lucas Ueberricke
- Organisch-Chemisches Institut, Ruprecht-Karls-Universität Heidelberg, Im Neuenheimer Feld 270, 69120, Heidelberg, Germany
| | - Bahiru Punja Benke
- Organisch-Chemisches Institut, Ruprecht-Karls-Universität Heidelberg, Im Neuenheimer Feld 270, 69120, Heidelberg, Germany
| | - Tobias Kirschbaum
- Organisch-Chemisches Institut, Ruprecht-Karls-Universität Heidelberg, Im Neuenheimer Feld 270, 69120, Heidelberg, Germany
| | - Sebastian Hahn
- Organisch-Chemisches Institut, Ruprecht-Karls-Universität Heidelberg, Im Neuenheimer Feld 270, 69120, Heidelberg, Germany
| | - Frank Rominger
- Organisch-Chemisches Institut, Ruprecht-Karls-Universität Heidelberg, Im Neuenheimer Feld 270, 69120, Heidelberg, Germany
| | - Uwe H F Bunz
- Organisch-Chemisches Institut, Ruprecht-Karls-Universität Heidelberg, Im Neuenheimer Feld 270, 69120, Heidelberg, Germany
| | - Michael Mastalerz
- Organisch-Chemisches Institut, Ruprecht-Karls-Universität Heidelberg, Im Neuenheimer Feld 270, 69120, Heidelberg, Germany
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16
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Full J, Panchal SP, Götz J, Krause A, Nowak‐Król A. Modulare Synthese helikal‐chiraler Organobor‐Verbindungen: Ausschnitte verlängerter Helices. Angew Chem Int Ed Engl 2021. [DOI: 10.1002/ange.202014138] [Citation(s) in RCA: 13] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Affiliation(s)
- Julian Full
- Institut für Anorganische Chemie Universität Würzburg Am Hubland 97074 Würzburg Deutschland
- Institut für Organische Chemie and Center for Nanosystems Chemistry Universität Würzburg Am Hubland 97074 Würzburg Deutschland
| | - Santosh P. Panchal
- Institut für Anorganische Chemie Universität Würzburg Am Hubland 97074 Würzburg Deutschland
- Institut für Organische Chemie and Center for Nanosystems Chemistry Universität Würzburg Am Hubland 97074 Würzburg Deutschland
| | - Julian Götz
- Institut für Organische Chemie and Center for Nanosystems Chemistry Universität Würzburg Am Hubland 97074 Würzburg Deutschland
| | - Ana‐Maria Krause
- Institut für Organische Chemie and Center for Nanosystems Chemistry Universität Würzburg Am Hubland 97074 Würzburg Deutschland
| | - Agnieszka Nowak‐Król
- Institut für Anorganische Chemie Universität Würzburg Am Hubland 97074 Würzburg Deutschland
- Institut für Organische Chemie and Center for Nanosystems Chemistry Universität Würzburg Am Hubland 97074 Würzburg Deutschland
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17
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Zhou Z, Zhu Y, Wei Z, Bergner J, Neiß C, Doloczki S, Görling A, Kivala M, Petrukhina MA. Reduction of π‐Expanded Cyclooctatetraene with Lithium: Stabilization of the Tetra‐Anion through Internal Li
+
Coordination. Angew Chem Int Ed Engl 2020. [DOI: 10.1002/ange.202013353] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Affiliation(s)
- Zheng Zhou
- Department of Chemistry University at Albany State University of New York 1400 Washington Ave. Albany NY 12222 USA
| | - Yikun Zhu
- Department of Chemistry University at Albany State University of New York 1400 Washington Ave. Albany NY 12222 USA
| | - Zheng Wei
- Department of Chemistry University at Albany State University of New York 1400 Washington Ave. Albany NY 12222 USA
| | - John Bergner
- Organisch-Chemisches Institut Ruprecht-Karls-Universität Heidelberg Im Neuenheimer Feld 270 69120 Heidelberg Germany
- Centre for Advanced Materials Ruprecht-Karls-Universität Heidelberg Im Neuenheimer Feld 225 69120 Heidelberg Germany
| | - Christian Neiß
- Department of Chemistry and Pharmacy Chair of Theoretical Chemistry Friedrich-Alexander-Universität Erlangen-Nürnberg Egerlandstr. 3 91058 Erlangen Germany
| | - Susanne Doloczki
- Department of Chemistry and Pharmacy Chair of Organic Chemistry I Friedrich-Alexander-Universität Erlangen-Nürnberg Nikolaus-Fiebiger-Str. 10 91058 Erlangen Germany
| | - Andreas Görling
- Department of Chemistry and Pharmacy Chair of Theoretical Chemistry Friedrich-Alexander-Universität Erlangen-Nürnberg Egerlandstr. 3 91058 Erlangen Germany
| | - Milan Kivala
- Organisch-Chemisches Institut Ruprecht-Karls-Universität Heidelberg Im Neuenheimer Feld 270 69120 Heidelberg Germany
- Centre for Advanced Materials Ruprecht-Karls-Universität Heidelberg Im Neuenheimer Feld 225 69120 Heidelberg Germany
| | - Marina A. Petrukhina
- Department of Chemistry University at Albany State University of New York 1400 Washington Ave. Albany NY 12222 USA
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18
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Zhu C, Shoyama K, Würthner F. Conformation and Aromaticity Switching in a Curved Non-Alternant sp 2 Carbon Scaffold. Angew Chem Int Ed Engl 2020; 59:21505-21509. [PMID: 32815658 PMCID: PMC7756343 DOI: 10.1002/anie.202010077] [Citation(s) in RCA: 48] [Impact Index Per Article: 12.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/22/2020] [Revised: 08/19/2020] [Indexed: 01/19/2023]
Abstract
A curved sp2 carbon scaffold containing fused pentagon and heptagon units (1) was synthesized by Pd-catalyzed [5+2] annulation from a 3,9-diboraperylene precursor and shows two reversible oxidation processes at low redox potential, accompanied by a butterfly-like motion. Stepwise oxidation produced radical cation 1.+ and dication 12+ . In the crystal structure, 1 exhibits a chiral cisoid conformation and partial π-overlap between the enantiomers. For the radical cation 1.+ , a less curved cisoid conformation is observed with a π-dimer-type arrangement. 12+ adopts a more planar structure with transoid conformation and slip-stacked π-overlap with closest neighbors. We also observed an intermolecular mixed-valence complex of 1⋅(1.+ )3 that has a huge trigonal unit cell [(1)72 (SbF6 )54 ⋅(hexane)101 ] and hexagonal columnar stacks. In addition to the conformational change, the aromaticity of 1 changes from localized to delocalized, as demonstrated by AICD and NICS(1)zz calculations.
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Affiliation(s)
- Chongwei Zhu
- Institut für Organische Chemie and Center for Nanosystems Chemistry (CNC)Universität WürzburgAm Hubland97074WürzburgGermany
| | - Kazutaka Shoyama
- Institut für Organische Chemie and Center for Nanosystems Chemistry (CNC)Universität WürzburgAm Hubland97074WürzburgGermany
| | - Frank Würthner
- Institut für Organische Chemie and Center for Nanosystems Chemistry (CNC)Universität WürzburgAm Hubland97074WürzburgGermany
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19
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Kirschbaum T, Rominger F, Mastalerz M. An Isosteric Triaza Analogue of a Polycyclic Aromatic Hydrocarbon Monkey Saddle. Chemistry 2020; 26:14560-14564. [PMID: 32539193 PMCID: PMC7756504 DOI: 10.1002/chem.202002826] [Citation(s) in RCA: 21] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/11/2020] [Indexed: 01/06/2023]
Abstract
Since a few years, the interest in negatively-curved fused polycyclic aromatic hydrocarbons (PAHs) has significantly increased. Recently, the first chiral negatively-curved PAH with the topology of a monkey saddle was introduced. Herein the synthesis of its triaza congener is reported. The influence of this CH↔N exchange on photophysical and electrochemical properties is studied as well as the isomerization process of the enantiomers. The aza analogue has a significantly higher inversion barrier, which makes it easier to handle at room temperature. All experimental results are underpinned by theoretical DFT calculations.
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Affiliation(s)
- Tobias Kirschbaum
- Organisch-Chemisches InstitutRuprecht-Karls-Universität HeidelbergIm Neuenheimer Feld 27069120HeidelbergGermany
| | - Frank Rominger
- Organisch-Chemisches InstitutRuprecht-Karls-Universität HeidelbergIm Neuenheimer Feld 27069120HeidelbergGermany
| | - Michael Mastalerz
- Organisch-Chemisches InstitutRuprecht-Karls-Universität HeidelbergIm Neuenheimer Feld 27069120HeidelbergGermany
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20
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Zhu C, Shoyama K, Würthner F. Conformation and Aromaticity Switching in a Curved Non‐Alternant sp
2
Carbon Scaffold. Angew Chem Int Ed Engl 2020. [DOI: 10.1002/ange.202010077] [Citation(s) in RCA: 17] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
Affiliation(s)
- Chongwei Zhu
- Institut für Organische Chemie and Center for Nanosystems Chemistry (CNC) Universität Würzburg Am Hubland 97074 Würzburg Germany
| | - Kazutaka Shoyama
- Institut für Organische Chemie and Center for Nanosystems Chemistry (CNC) Universität Würzburg Am Hubland 97074 Würzburg Germany
| | - Frank Würthner
- Institut für Organische Chemie and Center for Nanosystems Chemistry (CNC) Universität Würzburg Am Hubland 97074 Würzburg Germany
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21
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Báti G, Csókás D, Yong T, Tam SM, Shi RRS, Webster RD, Pápai I, García F, Stuparu MC. Mechanochemical Synthesis of Corannulene‐Based Curved Nanographenes. Angew Chem Int Ed Engl 2020. [DOI: 10.1002/ange.202007815] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023]
Affiliation(s)
- Gábor Báti
- Division of Chemistry and Biological Chemistry School of Physical and Mathematical Sciences Nanyang Technological University Singapore 21 Nanyang Link 637371 Singapore Singapore
| | - Dániel Csókás
- Institute of Organic Chemistry Research Centre for Natural Sciences Magyar tudósok körútja 2 1117 Budapest Hungary
| | - Teoh Yong
- Division of Chemistry and Biological Chemistry School of Physical and Mathematical Sciences Nanyang Technological University Singapore 21 Nanyang Link 637371 Singapore Singapore
| | - Si Man Tam
- Division of Chemistry and Biological Chemistry School of Physical and Mathematical Sciences Nanyang Technological University Singapore 21 Nanyang Link 637371 Singapore Singapore
| | - Raymond R. S. Shi
- Division of Chemistry and Biological Chemistry School of Physical and Mathematical Sciences Nanyang Technological University Singapore 21 Nanyang Link 637371 Singapore Singapore
| | - Richard D. Webster
- Division of Chemistry and Biological Chemistry School of Physical and Mathematical Sciences Nanyang Technological University Singapore 21 Nanyang Link 637371 Singapore Singapore
| | - Imre Pápai
- Institute of Organic Chemistry Research Centre for Natural Sciences Magyar tudósok körútja 2 1117 Budapest Hungary
| | - Felipe García
- Division of Chemistry and Biological Chemistry School of Physical and Mathematical Sciences Nanyang Technological University Singapore 21 Nanyang Link 637371 Singapore Singapore
| | - Mihaiela C. Stuparu
- Division of Chemistry and Biological Chemistry School of Physical and Mathematical Sciences Nanyang Technological University Singapore 21 Nanyang Link 637371 Singapore Singapore
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22
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Báti G, Csókás D, Yong T, Tam SM, Shi RRS, Webster RD, Pápai I, García F, Stuparu MC. Mechanochemical Synthesis of Corannulene‐Based Curved Nanographenes. Angew Chem Int Ed Engl 2020; 59:21620-21626. [DOI: 10.1002/anie.202007815] [Citation(s) in RCA: 21] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/01/2020] [Revised: 08/03/2020] [Indexed: 01/12/2023]
Affiliation(s)
- Gábor Báti
- Division of Chemistry and Biological Chemistry School of Physical and Mathematical Sciences Nanyang Technological University Singapore 21 Nanyang Link 637371 Singapore Singapore
| | - Dániel Csókás
- Institute of Organic Chemistry Research Centre for Natural Sciences Magyar tudósok körútja 2 1117 Budapest Hungary
| | - Teoh Yong
- Division of Chemistry and Biological Chemistry School of Physical and Mathematical Sciences Nanyang Technological University Singapore 21 Nanyang Link 637371 Singapore Singapore
| | - Si Man Tam
- Division of Chemistry and Biological Chemistry School of Physical and Mathematical Sciences Nanyang Technological University Singapore 21 Nanyang Link 637371 Singapore Singapore
| | - Raymond R. S. Shi
- Division of Chemistry and Biological Chemistry School of Physical and Mathematical Sciences Nanyang Technological University Singapore 21 Nanyang Link 637371 Singapore Singapore
| | - Richard D. Webster
- Division of Chemistry and Biological Chemistry School of Physical and Mathematical Sciences Nanyang Technological University Singapore 21 Nanyang Link 637371 Singapore Singapore
| | - Imre Pápai
- Institute of Organic Chemistry Research Centre for Natural Sciences Magyar tudósok körútja 2 1117 Budapest Hungary
| | - Felipe García
- Division of Chemistry and Biological Chemistry School of Physical and Mathematical Sciences Nanyang Technological University Singapore 21 Nanyang Link 637371 Singapore Singapore
| | - Mihaiela C. Stuparu
- Division of Chemistry and Biological Chemistry School of Physical and Mathematical Sciences Nanyang Technological University Singapore 21 Nanyang Link 637371 Singapore Singapore
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