1
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Artigas A, Carissan Y, Hagebaum-Reignier D, Bock H, Durola F, Coquerel Y. Aromaticity in Semi-Condensed Figure-Eight Molecules. Chemistry 2024:e202401016. [PMID: 38642001 DOI: 10.1002/chem.202401016] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/12/2024] [Revised: 04/08/2024] [Accepted: 04/19/2024] [Indexed: 04/22/2024]
Abstract
Electron delocalization and aromaticity was comparatively evaluated in recently synthesized figure-eight molecules made of two condensed U-shaped polycyclic aromatic hydrocarbon moieties connected either by two single bonds or by two para-phenylene groups. The selected examples include molecules that incorporate eight-membered and sixteen-membered rings, as well as a doubly [5]helicene-bridged (1,4)cyclophane. We probe whether some electron delocalization could occur through the stereogenic single bonds in these molecules: Is aromaticity purely (semi-)local, or possibly also global in these molecules? It was concluded that the situation can go from a purely (semi-)local character when the dihedral angle at the connecting single bonds is large, such as in biphenyl, to a predominantly (semi-)local character with a minor global contribution when the dihedral angle is small, such as in the para-phenylene connectors of the [5] helicene-bridged cyclophane.
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Affiliation(s)
- Albert Artigas
- Facultat de Ciències, Universitat de Girona, Campus Montilivi, Carrer de Maria Aurèlia Capmany i Farnès 69, 17003, Girona, Catalunya, Spain
| | - Yannick Carissan
- Aix Marseille Univ, CNRS, Centrale Méditerranée, iSm2, Marseille, France
| | | | - Harald Bock
- Centre de Recherche Paul Pascal, CNRS, 115 av. Schweitzer, 33600, Pessac, France
| | - Fabien Durola
- Centre de Recherche Paul Pascal, CNRS, 115 av. Schweitzer, 33600, Pessac, France
| | - Yoann Coquerel
- Aix Marseille Univ, CNRS, Centrale Méditerranée, iSm2, Marseille, France
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2
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An D, Zhang R, Zhu J, Wang T, Zhao Y, Lu X, Liu Y. From π-conjugated macrocycles to heterocycloarenes based on benzo[2,1- b:3,4- b']dithiophene (BDTh): size- and geometry-dependent host-guest properties. Chem Sci 2024; 15:4590-4601. [PMID: 38516086 PMCID: PMC10952093 DOI: 10.1039/d3sc05074b] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/27/2023] [Accepted: 02/19/2024] [Indexed: 03/23/2024] Open
Abstract
π-Conjugated macrocycles have been highly attractive due to their challenging synthesis, fascinating aesthetic structure and unique physical and chemical properties. Although some progress has been made in synthesis, the study of π-macrocycles with different structural characteristics and supramolecular interactions still faces major challenges. In this paper, two new single-bond linked macrocycles (MS-4T/MS-6T) were reported, and the corresponding vinyl-bridged heterocycloarenes (MF-4T/MF-6T) were synthesized by the periphery fusion strategy. Further studies have indicated that the structure of these four macrocycles is determined by both size and curvature, showing unique variations from nearly planar to bowl and then to saddle. Interestingly, the nearly planar MS-4T with a small size and the rigid saddle-shaped MF-6T show no obvious response to fullerenes C60 or C70, while the bowl-shaped MS-6T and MF-4T demonstrate a strong binding affinity towards fullerenes C60 and C70. What's more, two kinds of co-crystals with capsule-like configurations, MS-6T@C60 and MS-6T@C70, have been successfully obtained, among which the former shows a loose columnar arrangement while the latter displays a unique three-dimensional honeycomb arrangement that is extremely rare in supramolecular complexes. This work systematically studies the π-conjugated macrocycles and provides a new idea for the development of novel host-guest systems and further multifunctional applications.
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Affiliation(s)
- Dongyue An
- Department of Materials Science, State Key Laboratory of Molecular Engineering of Polymers, Fudan University Shanghai 200433 China
| | - Rong Zhang
- Department of Materials Science, State Key Laboratory of Molecular Engineering of Polymers, Fudan University Shanghai 200433 China
| | - Jiangyu Zhu
- Department of Materials Science, State Key Laboratory of Molecular Engineering of Polymers, Fudan University Shanghai 200433 China
| | - Teng Wang
- Department of Materials Science, State Key Laboratory of Molecular Engineering of Polymers, Fudan University Shanghai 200433 China
| | - Yan Zhao
- Department of Materials Science, State Key Laboratory of Molecular Engineering of Polymers, Fudan University Shanghai 200433 China
| | - Xuefeng Lu
- Department of Materials Science, State Key Laboratory of Molecular Engineering of Polymers, Fudan University Shanghai 200433 China
| | - Yunqi Liu
- Department of Materials Science, State Key Laboratory of Molecular Engineering of Polymers, Fudan University Shanghai 200433 China
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3
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Shi Y, Li C, Di J, Xue Y, Jia Y, Duan J, Hu X, Tian Y, Li Y, Sun C, Zhang N, Xiong Y, Jin T, Chen P. Polycationic Open-Shell Cyclophanes: Synthesis of Electron-Rich Chiral Macrocycles, and Redox-Dependent Electronic States. Angew Chem Int Ed Engl 2024:e202402800. [PMID: 38411404 DOI: 10.1002/anie.202402800] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/07/2024] [Revised: 02/20/2024] [Accepted: 02/23/2024] [Indexed: 02/28/2024]
Abstract
π-Conjugated chiral nanorings with intriguing electronic structures and chiroptical properties have attracted considerable interests in synthetic chemistry and materials science. We present the design principles to access new chiral macrocycles (1 and 2) that are essentially built on the key components of main-group electron-donating carbazolyl moieties or the π-expanded aza[7]helicenes. Both macrocycles show the unique molecular conformations with a (quasi) figure-of-eight topology as a result of the conjugation patterns of 2,2',7,7'-spirobifluorenyl in 1 and triarylamine-coupled aza[7]helicene-based building blocks in 2. This electronic nature of redox-active, carbazole-rich backbones enabled these macrocycles to be readily oxidized chemically and electrochemically, leading to the sequential production of a series of positively charged polycationic open-shell cyclophanes. Their redox-dependent electronic states of the resulting multispin polyradicals have been characterized by VT-ESR, UV/Vis-NIR absorption and spectroelectrochemical measurements. The singlet (ΔES-T=-1.29 kcal mol-1) and a nearly degenerate singlet-triplet ground state (ΔES-T(calcd)=-0.15 kcal mol-1 and ΔES-T(exp)=0.01 kcal mol-1) were proved for diradical dications 12+2⋅ and 22+2⋅, respectively. Our work provides an experimental proof for the construction of electron-donating new chiral nanorings, and more importantly for highly charged polyradicals with potential applications in chirospintronics and organic conductors.
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Affiliation(s)
- Yafei Shi
- Beijing Key Laboratory of Photoelectronic/Electrophotonic Conversion Materials, Key Laboratory of Medical Molecule Science, Pharmaceutical Engineering of the Ministry of Industry and Information Technology, School of Chemistry and Chemical Engineering, Beijing Institute of Technology, Beijing, 102488, China
| | - Chenglong Li
- Beijing Key Laboratory of Photoelectronic/Electrophotonic Conversion Materials, Key Laboratory of Medical Molecule Science, Pharmaceutical Engineering of the Ministry of Industry and Information Technology, School of Chemistry and Chemical Engineering, Beijing Institute of Technology, Beijing, 102488, China
| | - Jiaqi Di
- Beijing Key Laboratory of Photoelectronic/Electrophotonic Conversion Materials, Key Laboratory of Medical Molecule Science, Pharmaceutical Engineering of the Ministry of Industry and Information Technology, School of Chemistry and Chemical Engineering, Beijing Institute of Technology, Beijing, 102488, China
| | - Yuting Xue
- Beijing Key Laboratory of Photoelectronic/Electrophotonic Conversion Materials, Key Laboratory of Medical Molecule Science, Pharmaceutical Engineering of the Ministry of Industry and Information Technology, School of Chemistry and Chemical Engineering, Beijing Institute of Technology, Beijing, 102488, China
| | - Yawei Jia
- Beijing Key Laboratory of Photoelectronic/Electrophotonic Conversion Materials, Key Laboratory of Medical Molecule Science, Pharmaceutical Engineering of the Ministry of Industry and Information Technology, School of Chemistry and Chemical Engineering, Beijing Institute of Technology, Beijing, 102488, China
| | - Jiaxian Duan
- Beijing Key Laboratory of Photoelectronic/Electrophotonic Conversion Materials, Key Laboratory of Medical Molecule Science, Pharmaceutical Engineering of the Ministry of Industry and Information Technology, School of Chemistry and Chemical Engineering, Beijing Institute of Technology, Beijing, 102488, China
| | - Xiaoyu Hu
- Beijing Key Laboratory of Photoelectronic/Electrophotonic Conversion Materials, Key Laboratory of Medical Molecule Science, Pharmaceutical Engineering of the Ministry of Industry and Information Technology, School of Chemistry and Chemical Engineering, Beijing Institute of Technology, Beijing, 102488, China
| | - Yu Tian
- Beijing Key Laboratory of Photoelectronic/Electrophotonic Conversion Materials, Key Laboratory of Medical Molecule Science, Pharmaceutical Engineering of the Ministry of Industry and Information Technology, School of Chemistry and Chemical Engineering, Beijing Institute of Technology, Beijing, 102488, China
| | - Yanqiu Li
- Beijing Key Laboratory of Photoelectronic/Electrophotonic Conversion Materials, Key Laboratory of Medical Molecule Science, Pharmaceutical Engineering of the Ministry of Industry and Information Technology, School of Chemistry and Chemical Engineering, Beijing Institute of Technology, Beijing, 102488, China
| | - Cuiping Sun
- Beijing Key Laboratory of Photoelectronic/Electrophotonic Conversion Materials, Key Laboratory of Medical Molecule Science, Pharmaceutical Engineering of the Ministry of Industry and Information Technology, School of Chemistry and Chemical Engineering, Beijing Institute of Technology, Beijing, 102488, China
| | - Niu Zhang
- Analysis and Testing Centre, Beijing Institute of Technology, 102488, Beijing, China
| | - Yan Xiong
- Analysis and Testing Centre, Beijing Institute of Technology, 102488, Beijing, China
| | - Tianyun Jin
- Center of Marine Biotechnology and Biomedicine, Scripps Institution of Oceanography University of California, San Diego La Jolla, 92093, USA
| | - Pangkuan Chen
- Beijing Key Laboratory of Photoelectronic/Electrophotonic Conversion Materials, Key Laboratory of Medical Molecule Science, Pharmaceutical Engineering of the Ministry of Industry and Information Technology, School of Chemistry and Chemical Engineering, Beijing Institute of Technology, Beijing, 102488, China
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4
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Chang X, Xu Y, von Delius M. Recent advances in supramolecular fullerene chemistry. Chem Soc Rev 2024; 53:47-83. [PMID: 37853792 PMCID: PMC10759306 DOI: 10.1039/d2cs00937d] [Citation(s) in RCA: 7] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/01/2023] [Indexed: 10/20/2023]
Abstract
Fullerene chemistry has come a long way since 1990, when the first bulk production of C60 was reported. In the past decade, progress in supramolecular chemistry has opened some remarkable and previously unexpected opportunities regarding the selective (multiple) functionalization of fullerenes and their (self)assembly into larger structures and frameworks. The purpose of this review article is to provide a comprehensive overview of these recent developments. We describe how macrocycles and cages that bind strongly to C60 can be used to block undesired addition patterns and thus allow the selective preparation of single-isomer addition products. We also discuss how the emergence of highly shape-persistent macrocycles has opened opportunities for the study of photoactive fullerene dyads and triads as well as the preparation of mechanically interlocked compounds. The preparation of two- or three-dimensional fullerene materials is another research area that has seen remarkable progress over the past few years. Due to the rapidly decreasing price of C60 and C70, we believe that these achievements will translate into all fields where fullerenes have traditionally (third-generation solar cells) and more recently been applied (catalysis, spintronics).
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Affiliation(s)
- Xingmao Chang
- College of Chemistry and Molecular Sciences, Henan University, Kaifeng 475004, China.
- Institute of Organic Chemistry, Ulm University, Ulm 89081, Germany.
| | - Youzhi Xu
- College of Chemistry and Molecular Sciences, Henan University, Kaifeng 475004, China.
| | - Max von Delius
- Institute of Organic Chemistry, Ulm University, Ulm 89081, Germany.
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Gu Q, Lu X, Chen C, Hu R, Wang X, Sun G, Kang F, Yang J, Wang X, Wu J, Li YY, Peng YK, Qin W, Han Y, Liu X, Zhang Q. Thermally Induced Persistent Covalent-Organic Frameworks Radicals. ACS NANO 2023. [PMID: 38014811 DOI: 10.1021/acsnano.3c08313] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/29/2023]
Abstract
Persistent covalent-organic framework (COF) radicals hold important applications in magnetics and spintronics; however, their facile synthesis remains a daunting challenge. Here, three p-phenylenediacetonitrile-based COFs (named CityU-4, CityU-5, and CityU-6) were synthesized. Upon heat treatment (250 °C for CityU-4 and CityU-5 or 220 °C for CityU-6), these frameworks were brought into their persistent radical forms (no obvious changes after at least one year), together with several observable factors, including color changes, red-shifted absorption, the appearance of electron spin resonance (ESR) signals, and detectable magnetic susceptibility. The theoretical simulation suggests that after heat treatment, lower total energy and nonzero spin density are two main factors to guarantee persistent COFs radicals and polarized spin distributions. This work provides an efficient method for the preparation of persistent COF radicals with promising potentials.
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Affiliation(s)
- Qianfeng Gu
- Department of Materials Science and Engineering, City University of Hong Kong, Tat Chee Avenue 83, Kowloon, Hong Kong SAR 999077, P. R. China
| | - Xiangqian Lu
- School of Physics, State Key Laboratory of Crystal Materials, Shandong University, Jinan 250100, P. R. China
| | - Cailing Chen
- Advanced Membranes and Porous Materials (AMPM) Center, Physical Science and Engineering Division, King Ab-dullah University of Science and Technology (KAUST), Thuwal 23955-6900, Saudi Arabia
| | - Renjie Hu
- School of Physics, State Key Laboratory of Crystal Materials, Shandong University, Jinan 250100, P. R. China
| | - Xin Wang
- Department of Materials Science and Engineering, City University of Hong Kong, Tat Chee Avenue 83, Kowloon, Hong Kong SAR 999077, P. R. China
| | - Guohan Sun
- Department of Chemistry, City University of Hong Kong, Tat Chee Avenue 83, Kowloon, Hong Kong SAR 999077, P. R. China
| | - Fangyuan Kang
- Department of Materials Science and Engineering, City University of Hong Kong, Tat Chee Avenue 83, Kowloon, Hong Kong SAR 999077, P. R. China
| | - Jinglun Yang
- Department of Materials Science and Engineering, City University of Hong Kong, Tat Chee Avenue 83, Kowloon, Hong Kong SAR 999077, P. R. China
| | - Xiang Wang
- Department of Materials Science and Engineering, City University of Hong Kong, Tat Chee Avenue 83, Kowloon, Hong Kong SAR 999077, P. R. China
| | - Jinghang Wu
- Department of Materials Science and Engineering, City University of Hong Kong, Tat Chee Avenue 83, Kowloon, Hong Kong SAR 999077, P. R. China
| | - Yang Yang Li
- Department of Materials Science and Engineering, City University of Hong Kong, Tat Chee Avenue 83, Kowloon, Hong Kong SAR 999077, P. R. China
| | - Yung-Kang Peng
- Department of Chemistry, City University of Hong Kong, Tat Chee Avenue 83, Kowloon, Hong Kong SAR 999077, P. R. China
| | - Wei Qin
- School of Physics, State Key Laboratory of Crystal Materials, Shandong University, Jinan 250100, P. R. China
| | - Yu Han
- Advanced Membranes and Porous Materials (AMPM) Center, Physical Science and Engineering Division, King Ab-dullah University of Science and Technology (KAUST), Thuwal 23955-6900, Saudi Arabia
| | - Xiaogang Liu
- Department of Chemistry and the N.1 Institute for Health, National University of Singapore, Singapore 117543, Singapore
| | - Qichun Zhang
- Department of Materials Science and Engineering, City University of Hong Kong, Tat Chee Avenue 83, Kowloon, Hong Kong SAR 999077, P. R. China
- Department of Chemistry & Center of Super-Diamond and Advanced Films (COSDAF), City University of Hong Kong, Tat Chee Avenue 83, Kowloon, Hong Kong SAR 999077, P. R. China
- Department of Chemistry, City University of Hong Kong, Tat Chee Avenue 83, Kowloon, Hong Kong SAR 999077, P. R. China
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6
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Das S, Sai Naik MB, Maliyekkal G, Maity SB, Jana A. Recent update on the electroactive oligopyrrolic macrocyclic hosts with a Bucky-ball heart. Chem Commun (Camb) 2023; 59:12972-12985. [PMID: 37828866 DOI: 10.1039/d3cc04028c] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/14/2023]
Abstract
Supramolecular chemistry is a multidisciplinary research area mostly associated with the investigation of host-guest interactions within intricate three-dimensional (3D) molecular architectures held together reversibly by various non-covalent interactions. Continuous efforts to develop such kinds of complex host-guest systems with designer oligopyrrolic macrocyclic receptors are a rapidly growing research domain, which is deeply involved in applied supramolecular chemistry research. These host-guest supramolecular complexes can be constructed by combining suitable electron-rich oligopyrrolic donors (as a host) with complementary electron-poor guests (as acceptors), held together by the ionic force of attraction triggered by intermolecular charge/electron transfer (CT/ET) transitions. Some of these resulting CT/ET ensembles are potential candidates for the construction of efficient optoelectronic materials, optical sensors, molecular switches, etc. In this Feature Article we aim to focus on these supramolecular ensembles composed by size and shape complementary electroactive oligopyrrolic molecular containers, which are suitable for spherical guest (e.g., buckminsterfullerene) complexation. We also provide a "state-of-the-art" overview on plausible applications of these particular host-guest systems. Our aim is to cover only specific electron-rich tetrathiafulvalene (TTF)-based oligopyrrolic receptors, e.g., TTF-calix[4]pyrroles, TTF-cryptands, TTF-porphyrins and exTTF-porphyrin-based molecular motifs reported to date, along with a brief outlining of their "functional behaviour" in materials chemistry research.
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Affiliation(s)
- Shubhasree Das
- Applied Supramolecular Chemistry Research Laboratory, Department of Chemistry, Gandhi Institute of Technology and Management (GITAM), Gandhinagar, Rushikonda, Visakhapatnam - 530045, Andhra Pradesh, India.
| | - M Bhargav Sai Naik
- Applied Supramolecular Chemistry Research Laboratory, Department of Chemistry, Gandhi Institute of Technology and Management (GITAM), Gandhinagar, Rushikonda, Visakhapatnam - 530045, Andhra Pradesh, India.
| | - Godwin Maliyekkal
- Department of Chemical Sciences, IISER Mohali, Manauli - 140306, Punjab, India
| | - Shubhra Bikash Maity
- Faculty of Physical and Mathematical Sciences, Department of Chemistry, C. V. Raman Global University, Bhubaneswar - 752054, India
| | - Atanu Jana
- Applied Supramolecular Chemistry Research Laboratory, Department of Chemistry, Gandhi Institute of Technology and Management (GITAM), Gandhinagar, Rushikonda, Visakhapatnam - 530045, Andhra Pradesh, India.
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Kang HW, Liu YC, Shao WK, Wei YC, Hsieh CT, Chen BH, Lu CH, Yang SD, Cheng MJ, Chou PT, Chiang MH, Wu YT. Synthesis, structural analysis, and properties of highly twisted alkenes 13,13'-bis(dibenzo[a,i]fluorenylidene) and its derivatives. Nat Commun 2023; 14:5248. [PMID: 37640729 PMCID: PMC10462764 DOI: 10.1038/s41467-023-40990-8] [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: 06/07/2023] [Accepted: 08/18/2023] [Indexed: 08/31/2023] Open
Abstract
The rotation of a C = C bond in an alkene can be efficiently accelerated by creating the high-strain ground state and stabilizing the transition state of the process. Herein, the synthesis, structures, and properties of several highly twisted alkenes are comprehensively explored. A facile and practical synthetic approach to target molecules is developed. The twist angles and lengths of the central C = C bonds in these molecules are 36-58° and 1.40-1.43 Å, respectively, and confirmed by X-ray crystallography and DFT calculations. A quasi-planar molecular half with the π-extended substituents delivers a shallow rotational barrier (down to 2.35 kcal/mol), indicating that the rotation of the C = C bond is as facile as that of the aryl-aryl bond in 2-flourobiphenyl. Other versatile and unique properties of the studied compounds include a broad photoabsorption range (from 250 up to 1100 nm), a reduced HOMO-LUMO gap (1.26-1.68 eV), and a small singlet-triplet energy gap (3.65-5.68 kcal/mol).
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Affiliation(s)
- Hao-Wen Kang
- Department of Chemistry, National Cheng Kung University, 70101, Tainan, Taiwan
| | - Yu-Chiao Liu
- Institute of Chemistry, Academia Sinica, 11529, Taipei, Taiwan
| | - Wei-Kai Shao
- Department of Chemistry, National Cheng Kung University, 70101, Tainan, Taiwan
| | - Yu-Chen Wei
- Department of Chemistry, National Taiwan University, 10617, Taipei, Taiwan
| | - Chi-Tien Hsieh
- Department of Chemistry, National Cheng Kung University, 70101, Tainan, Taiwan
| | - Bo-Han Chen
- Department of Electrical Engineering, National Tsing Hua University, 30013, Hsinchu, Taiwan
| | - Chih-Hsuan Lu
- Department of Electrical Engineering, National Tsing Hua University, 30013, Hsinchu, Taiwan
| | - Shang-Da Yang
- Department of Electrical Engineering, National Tsing Hua University, 30013, Hsinchu, Taiwan
| | - Mu-Jeng Cheng
- Department of Chemistry, National Cheng Kung University, 70101, Tainan, Taiwan
| | - Pi-Tai Chou
- Department of Chemistry, National Taiwan University, 10617, Taipei, Taiwan.
| | - Ming-Hsi Chiang
- Institute of Chemistry, Academia Sinica, 11529, Taipei, Taiwan.
- Department of Medical and Applied Chemistry, Kaohsiung Medical University, 80708, Kaohsiung, Taiwan.
| | - Yao-Ting Wu
- Department of Chemistry, National Cheng Kung University, 70101, Tainan, Taiwan.
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8
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Kundu G, Dash SR, Kumar R, Vanka K, Ghosh A, Sen SS. Enhancing Diradical Character of Chichibabin's Hydrocarbon through Fluoride Substitution. Chempluschem 2023; 88:e202300273. [PMID: 37409641 DOI: 10.1002/cplu.202300273] [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: 06/07/2023] [Revised: 07/04/2023] [Accepted: 07/06/2023] [Indexed: 07/07/2023]
Abstract
In this work, 5-SIDipp [SIDipp=1,3-bis(2,6-diisopropylphenyl)-imidazolin-2-ylidene] (1) derived Chichibabin's hydrocarbon with an octafluorobiphenylene spacer (3) has been reported. The addition of two equivalents of 5-SIDipp with decafluorobiphenyl in presence of BF3 gives the double C-F bond activated imidazolium salt with two tetrafluoroborate anions, 2. Further reduction of 2 gives the fluorine substituted 5-SIDipp based Chichibabin's hydrocarbon, 3. Quantum chemical calculations suggested a singlet state of 3 with a singlet-triplet energy gap (ΔES-T ) of 3.7 kcal mol-1 , which is substantially lower with respect to the hydrogen substituted NHC-based Chichibabin's hydrocarbons (10.7 kcal mol-1 , B3LYP). As a result, the diradical character (y) of 3 (y=0.62) is also noticeably higher than the hydrogen substituted CHs (y=0.41-0.43). The ▵ES-T was found to be higher in CASSCF (22.24 kcal mol-1 ) and CASPT2 (11.17 kcal mol-1 ) for 3 and the diradical character (d) is 44.6 %.
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Affiliation(s)
- Gargi Kundu
- Inorganic Chemistry and Catalysis Division, CSIR-National Chemical Laboratory, Dr. Homi Bhabha Road Pashan, Pune, 411008, India
- Academy of Scientific and Innovative Research (AcSIR), Ghaziabad, 201002, India
| | - Soumya Ranjan Dash
- Academy of Scientific and Innovative Research (AcSIR), Ghaziabad, 201002, India
- Physical and Materials Chemistry Division, CSIR-National Chemical Laboratory, Dr. Homi Bhabha Road Pashan, Pune, 411008, India
| | - Ravi Kumar
- Academy of Scientific and Innovative Research (AcSIR), Ghaziabad, 201002, India
- Physical and Materials Chemistry Division, CSIR-National Chemical Laboratory, Dr. Homi Bhabha Road Pashan, Pune, 411008, India
| | - Kumar Vanka
- Academy of Scientific and Innovative Research (AcSIR), Ghaziabad, 201002, India
- Physical and Materials Chemistry Division, CSIR-National Chemical Laboratory, Dr. Homi Bhabha Road Pashan, Pune, 411008, India
| | - Aryya Ghosh
- Department of Chemistry, Ashoka University, Sonipat, Haryana, 131029, India
| | - Sakya S Sen
- Inorganic Chemistry and Catalysis Division, CSIR-National Chemical Laboratory, Dr. Homi Bhabha Road Pashan, Pune, 411008, India
- Academy of Scientific and Innovative Research (AcSIR), Ghaziabad, 201002, India
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9
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Wang P, Hu J, Xu Z, Pu Z, Sato S, Zhang X, Hu W, Sun Z. Synthesis and structure elucidation of triarylmethyl radicals with anthryl substitution. Chem Commun (Camb) 2023; 59:2015-2018. [PMID: 36723079 DOI: 10.1039/d2cc06083c] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/26/2023]
Abstract
Two stable triarylmethyl radicals with one or two anthryl substitutions are synthesized in gram scale, and are isolated in the crystalline state. Detailed structural elucidation with X-ray crystallographic analysis and DFT calculations revealed that the twisted structure is more energetically favorable than the folded structure, and consequently, the spin density is mainly localized at the methyl carbon. The spin distribution leads to unique physical properties, making them promising open-shell organic materials.
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Affiliation(s)
- Peng Wang
- Institute of Molecular Plus, Department of Chemistry, Tianjin University, 92 Weijin Road, Tianjin, 300072, China. .,Tianjin Key Laboratory of Molecular Optoelectronic Sciences, Department of Chemistry, School of Science, Tianjin University, Tianjin 300072, China.
| | - Jinlian Hu
- Institute of Molecular Plus, Department of Chemistry, Tianjin University, 92 Weijin Road, Tianjin, 300072, China.
| | - Zhuofan Xu
- Institute of Molecular Plus, Department of Chemistry, Tianjin University, 92 Weijin Road, Tianjin, 300072, China.
| | - Zhaofangzhou Pu
- Institute of Molecular Plus, Department of Chemistry, Tianjin University, 92 Weijin Road, Tianjin, 300072, China.
| | - Sota Sato
- Department of Applied Chemistry, Integrated Molecular Structure Analysis Laboratory, Social Cooperation Program, The University of Tokyo, Hongo, Bunkyo-ku, Tokyo 113-8656, Japan
| | - Xiaotao Zhang
- Institute of Molecular Aggregation Science, Tianjin University, Tianjin 300072, China.
| | - Wenping Hu
- Tianjin Key Laboratory of Molecular Optoelectronic Sciences, Department of Chemistry, School of Science, Tianjin University, Tianjin 300072, China. .,Haihe Laboratory of Sustainable Chemical Transformations, Tianjin 300192, China
| | - Zhe Sun
- Institute of Molecular Plus, Department of Chemistry, Tianjin University, 92 Weijin Road, Tianjin, 300072, China. .,Tianjin Key Laboratory of Molecular Optoelectronic Sciences, Department of Chemistry, School of Science, Tianjin University, Tianjin 300072, China. .,Haihe Laboratory of Sustainable Chemical Transformations, Tianjin 300192, China
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10
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Bera S, Das S, Melle-Franco M, Mateo-Alonso A. An Organic Molecular Nanobarrel that Hosts and Solubilizes C 60. Angew Chem Int Ed Engl 2023; 62:e202216540. [PMID: 36469042 PMCID: PMC10107786 DOI: 10.1002/anie.202216540] [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: 11/09/2022] [Revised: 12/05/2022] [Accepted: 12/05/2022] [Indexed: 12/12/2022]
Abstract
Organic cages have gained increasing attention in recent years as molecular hosts and porous materials. Among these, barrel-shaped cages or molecular nanobarrels are promising systems to encapsulate large hosts as they possess windows of the same size as their internal cavity. However, these systems have received little attention and remain practically unexplored despite their potential. Herein, we report the design and synthesis of a new trigonal prismatic organic nanobarrel with two large triangular windows with a diameter of 12.7 Å optimal for the encapsulation of C60 . Remarkably, this organic nanobarrel shows a high affinity for C60 in solvents in which C60 is virtually insoluble, providing stable solutions of C60 .
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Affiliation(s)
- Saibal Bera
- POLYMAT, University of the Basque Country UPV/EHU, Avenida de Tolosa 72, 20018, Donostia-San Sebastián, Spain
| | - Satyajit Das
- POLYMAT, University of the Basque Country UPV/EHU, Avenida de Tolosa 72, 20018, Donostia-San Sebastián, Spain
| | - Manuel Melle-Franco
- CICECO-Aveiro Institute of Materials, Department of Chemistry, University of Aveiro, 3810-193, Aveiro, Portugal
| | - Aurelio Mateo-Alonso
- POLYMAT, University of the Basque Country UPV/EHU, Avenida de Tolosa 72, 20018, Donostia-San Sebastián, Spain.,Ikerbasque, Basque Foundation for Science, 48009, Bilbao, Spain
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11
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Hayashi Y, Suzuki S, Suzuki T, Ishigaki Y. Dibenzotropylium-Capped Orthogonal Geometry Enabling Isolation and Examination of a Series of Hydrocarbons with Multiple 14π-Aromatic Units. J Am Chem Soc 2023; 145:2596-2608. [PMID: 36606368 PMCID: PMC9896550 DOI: 10.1021/jacs.2c12574] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/07/2023]
Abstract
A series of six dications composed of pure hydrocarbons with one to six non-substituted 9,10-anthrylene units end-capped with two dibenzotropyliums were designed and synthesized to elucidate the electronic properties of huge oligo(9,10-anthrylene) backbones. Their structures were successfully determined by X-ray analyses even in the case of eight planar 14π-electron units, revealing that all dications adopt almost orthogonally twisted structures between neighboring units. Spectroscopic and voltammetric analyses show that neither the significant overlap of orbitals nor the delocalization of electrons between 14π-electron units occurs due to the orthogonally twisted geometry even in solution. As a result, sequential oxidation processes were observed with the reversible formation of multivalent cations with the release of the same number of electrons as the number of anthrylene units. Upon two-electron reduction, a closed-shell butterfly-shaped form was obtained from the dication containing one anthrylene unit, whereas open-shell twisted biradicals were isolated as stable entities in the cases of derivatives containing three to six anthrylene units. Notably, from the derivative with two anthrylene units, a metastable open-shell isomer was obtained quantitatively and underwent slow thermal conversion to the most stable closed-shell isomer (Ea = 23.1 kcal mol-1). There is a drastic change in oxidation potentials between two neutral species (ΔE = 1.32 V in CH2Cl2). Since the present dications were regenerated upon oxidation of the isolated reduction products, these systems may contribute to the development of advanced response systems capable of switching color, magnetic properties, and oxidative properties by using a "cation-capped orthogonal geometry".
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Affiliation(s)
- Yuki Hayashi
- Department
of Chemistry, Faculty of Science, Hokkaido
University, Sapporo 060-0810, Japan
| | - Shuichi Suzuki
- Graduate
School of Engineering Science, Osaka University, Osaka 560-8531, Japan
| | - Takanori Suzuki
- Department
of Chemistry, Faculty of Science, Hokkaido
University, Sapporo 060-0810, Japan
| | - Yusuke Ishigaki
- Department
of Chemistry, Faculty of Science, Hokkaido
University, Sapporo 060-0810, Japan,
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12
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Dai Y, Xie Z, Bao M, Liu C, Su Y. Multiple stable redox states and tunable ground states via the marriage of viologens and Chichibabin's hydrocarbon †. Chem Sci 2023; 14:3548-3553. [PMID: 37006684 PMCID: PMC10056129 DOI: 10.1039/d3sc00102d] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/08/2023] [Accepted: 02/28/2023] [Indexed: 03/30/2023] Open
Abstract
Chichibabin's hydrocarbon and viologens are among the most famous diradicaloids and organic redox systems, respectively. However, each has its own disadvantages: the instability of the former and its charged species, and the closed-shell nature of the neutral species derived from the latter, respectively. Herein, we report that terminal borylation and central distortion of 4,4′-bipyridine allow us to readily isolate the first bis-BN-based analogues (1 and 2) of Chichibabin's hydrocarbon with three stable redox states and tunable ground states. Electrochemically, both compounds exhibit two reversible oxidation processes with wide redox ranges. One- and two-electron chemical oxidations of 1 afford the crystalline radical cation 1˙+ and dication 12+, respectively. Moreover, the ground states of 1 and 2 are tunable with 1 as a closed-shell singlet and the tetramethyl-substituted 2 as an open-shell singlet, the latter of which could be thermally excited to its triplet state because of the small singlet-triplet gap. Herein, we report the isolation of bis-BN-based species 1 and 2 with multiple stable redox states. Their ground states are tunable with 1 as a closed-shell singlet and 2 as an open-shell singlet with a small singlet-triplet gap.![]()
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Affiliation(s)
- Yuyang Dai
- College of Chemistry, Chemical Engineering and Materials Science, School of Radiation Medicine and Protection, Soochow UniversitySuzhou 215123China
| | - Zhuofeng Xie
- College of Chemistry, Chemical Engineering and Materials Science, School of Radiation Medicine and Protection, Soochow UniversitySuzhou 215123China
| | - Manling Bao
- College of Chemistry, Chemical Engineering and Materials Science, School of Radiation Medicine and Protection, Soochow UniversitySuzhou 215123China
| | - Chunmeng Liu
- College of Chemistry, Chemical Engineering and Materials Science, School of Radiation Medicine and Protection, Soochow UniversitySuzhou 215123China
| | - Yuanting Su
- College of Chemistry, Chemical Engineering and Materials Science, School of Radiation Medicine and Protection, Soochow UniversitySuzhou 215123China
- State Key Laboratory of Coordination Chemistry, Nanjing UniversityNanjing 210023China
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13
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Design of an open-shell nitrogen-centered diradicaloid with tunable stimuli-responsive electronic properties. Commun Chem 2022; 5:127. [PMID: 36697916 PMCID: PMC9814612 DOI: 10.1038/s42004-022-00747-8] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/30/2022] [Accepted: 10/03/2022] [Indexed: 01/28/2023] Open
Abstract
Organic diradicaloids usually display an open-shell singlet ground state with significant singlet diradical character (y0) which endow them with intriguing physiochemical properties and wide applications. In this study, we present the design of an open-shell nitrogen-centered diradicaloid which can reversibly respond to multiple stimuli and display the tunable diradical character and chemo-physical properties. 1a was successfully synthesized through a simple and high-yielding two-step synthetic strategy. Both experimental and calculated results indicated that 1a displayed an open-shell singlet ground state with small singlet-triplet energy gap (ΔES-T = -2.311 kcal mol-1) and a modest diradical character (y0 = 0.60). Interestingly, 1a was demonstrated to undergo reversible Lewis acid-base reaction to form acid-base adducts, which was proven to effectively tune the ground-state electronic structures of 1a as well as its diradical character and spin density distributions. Based on this, we succeeded in devising a photoresponsive system based on 1a and a commercially available photoacid merocyanine (MEH). We believe that our studies including the molecular design methodology and the stimuli-responsive organic diradicaloid system will open up a new way to develop organic diradicaloids with tunable properties and even intelligent-responsive diradicaloid-based materials.
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14
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He L, Jiang C, Chen Z, Ma D, Yi L, Xi Z. A triple-diazonium reagent for virus crosslinking and the synthesis of an azo-linked molecular cage. Org Biomol Chem 2022; 20:7577-7581. [PMID: 36131636 DOI: 10.1039/d2ob01583h] [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
The first bench-stable triple-diazonium reagent (TDA-1) was rationally designed and synthesized for coupling and crosslinking. The three reactive sites of TDA-1 can react with phenol-containing molecules as well as plant viruses in aqueous buffers efficiently. In addition, a new-type azo-linked cage was constructed by the direct reaction of TDA-1 with a triple-phenol molecule and was characterized by X-ray crystallography.
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Affiliation(s)
- Lijun He
- State Key Laboratory of Organic-Inorganic Composites and Beijing Key Lab of Bioprocess, Beijing University of Chemical Technology, Beijing 100029, China.
| | - Chenyang Jiang
- State Key Laboratory of Organic-Inorganic Composites and Beijing Key Lab of Bioprocess, Beijing University of Chemical Technology, Beijing 100029, China.
| | - Zhuoyue Chen
- State Key Laboratory of Organic-Inorganic Composites and Beijing Key Lab of Bioprocess, Beijing University of Chemical Technology, Beijing 100029, China.
| | - Dejun Ma
- State Key Laboratory of Elemento-Organic Chemistry and Department of Chemical Biology, College of Chemistry, National Pesticide Engineering Research Center, Collaborative Innovation Center of Chemical Science and Engineering, Nankai University, Tianjin 300071, China.
| | - Long Yi
- State Key Laboratory of Organic-Inorganic Composites and Beijing Key Lab of Bioprocess, Beijing University of Chemical Technology, Beijing 100029, China.
| | - Zhen Xi
- State Key Laboratory of Elemento-Organic Chemistry and Department of Chemical Biology, College of Chemistry, National Pesticide Engineering Research Center, Collaborative Innovation Center of Chemical Science and Engineering, Nankai University, Tianjin 300071, China.
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15
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Li Z, Hou X, Han Y, Fan W, Ni Y, Zhou Q, Zhu J, Wu S, Huang K, Wu J. [8]Cyclo‐
para
‐phenylmethine as A Super‐Cyclooctatetraene: Dynamic Behavior, Global Aromaticity, and Open‐Shell Diradical Character in The Neutral and Dicationic States. Angew Chem Int Ed Engl 2022; 61:e202210697. [DOI: 10.1002/anie.202210697] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/20/2022] [Indexed: 11/11/2022]
Affiliation(s)
- Zhengtao Li
- Department of Chemistry National University of Singapore 3 Science Drive 3 117543 Singapore Singapore
| | - Xudong Hou
- Department of Chemistry National University of Singapore 3 Science Drive 3 117543 Singapore Singapore
| | - Yi Han
- Department of Chemistry National University of Singapore 3 Science Drive 3 117543 Singapore Singapore
| | - Wei Fan
- Department of Chemistry National University of Singapore 3 Science Drive 3 117543 Singapore Singapore
| | - Yong Ni
- Department of Chemistry National University of Singapore 3 Science Drive 3 117543 Singapore Singapore
| | - Qifeng Zhou
- Department of Chemistry National University of Singapore 3 Science Drive 3 117543 Singapore Singapore
- Joint School of National University of Singapore and Tianjin University International Campus of Tianjin University Binhai New City, Fuzhou 350207 China
| | - Jun Zhu
- Department of Chemistry National University of Singapore 3 Science Drive 3 117543 Singapore Singapore
| | - Shaofei Wu
- Department of Chemistry National University of Singapore 3 Science Drive 3 117543 Singapore Singapore
| | - Kuo‐Wei Huang
- KAUST Catalysis Center and Division of Physical Science and Engineering King Abdullah University of Science and Technology Thuwal 23955-6900 Saudi Arabia
- Institute of Materials Research and Engineering and Institute of Sustainability for Chemicals Energy and Environment Agency for Science, Technology, and Research (A*STAR) Singapore 138634 Singapore
| | - Jishan Wu
- Department of Chemistry National University of Singapore 3 Science Drive 3 117543 Singapore Singapore
- Joint School of National University of Singapore and Tianjin University International Campus of Tianjin University Binhai New City, Fuzhou 350207 China
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16
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Wang Y, Gong Q, Pun SH, Lee HK, Zhou Y, Xu J, Miao Q. Robust Radical Cations of Hexabenzoperylene Exhibiting High Conductivity and Enabling an Organic Nonvolatile Optoelectronic Memory. J Am Chem Soc 2022; 144:16612-16619. [PMID: 36043840 DOI: 10.1021/jacs.2c06835] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Herein, we report robust π-conjugated radical cations resulting from the oxidation of hexabenzoperylene (HBP) derivatives, HBP-B and HBP-H, which have butyl and hexyl groups, respectively, attached to the same twisted double helicene π-backbone. The radical cation of HBP-B was successfully crystallized in the form of hexafluorophosphate, which exhibited conductivity as high as 1.32 ± 0.04 S cm-1. Photochemical oxidation of HBP-H by molecular oxygen led to the formation of its radical cation in the solid state, as found with different techniques. This allowed the organic field effect transistor of HBP-H to function as a nonvolatile optoelectronic memory, with the memory switching contrast above 103 and long-term stability without using a floating gate, an electret layer, or photochromic molecules.
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Affiliation(s)
- Yujing Wang
- Department of Chemistry, The Chinese University of Hong Kong, Shatin, New Territories, Hong Kong, China
| | - Qi Gong
- Department of Chemistry, The Chinese University of Hong Kong, Shatin, New Territories, Hong Kong, China
| | - Sai Ho Pun
- Department of Chemistry, The Chinese University of Hong Kong, Shatin, New Territories, Hong Kong, China
| | - Hung Kay Lee
- Department of Chemistry, The Chinese University of Hong Kong, Shatin, New Territories, Hong Kong, China
| | - Yaoqiang Zhou
- Department of Electronic Engineering, The Chinese University of Hong Kong, Shatin, New Territories, Hong Kong, China
| | - Jianbin Xu
- Department of Electronic Engineering, The Chinese University of Hong Kong, Shatin, New Territories, Hong Kong, China
| | - Qian Miao
- Department of Chemistry, The Chinese University of Hong Kong, Shatin, New Territories, Hong Kong, China
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17
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[8]Cyclo‐para‐phenylmethine as A Super‐Cyclooctatetraene: Dynamic Behavior, Global Aromaticity, and Open‐Shell Diradical Character in The Neutral and Dicationic States. Angew Chem Int Ed Engl 2022. [DOI: 10.1002/ange.202210697] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
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18
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Gu Y, Qiu Z, Müllen K. Nanographenes and Graphene Nanoribbons as Multitalents of Present and Future Materials Science. J Am Chem Soc 2022; 144:11499-11524. [PMID: 35671225 PMCID: PMC9264366 DOI: 10.1021/jacs.2c02491] [Citation(s) in RCA: 39] [Impact Index Per Article: 19.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/25/2023]
Abstract
As cut-outs from a graphene sheet, nanographenes (NGs) and graphene nanoribbons (GNRs) are ideal cases with which to connect the world of molecules with that of bulk carbon materials. While various top-down approaches have been developed to produce such nanostructures in high yields, in the present perspective, precision structural control is emphasized for the length, width, and edge structures of NGs and GNRs achieved by modern solution and on-surface syntheses. Their structural possibilities have been further extended from "flatland" to the three-dimensional world, where chirality and handedness are the jewels in the crown. In addition to properties exhibited at the molecular level, self-assembly and thin-film structures cannot be neglected, which emphasizes the importance of processing techniques. With the rich toolkit of chemistry in hand, NGs and GNRs can be endowed with versatile properties and functions ranging from stimulated emission to spintronics and from bioimaging to energy storage, thus demonstrating their multitalents in present and future materials science.
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Affiliation(s)
- Yanwei Gu
- Max
Planck Institute for Polymer Research, Ackermannweg 10, 55128 Mainz, Germany
| | - Zijie Qiu
- Max
Planck Institute for Polymer Research, Ackermannweg 10, 55128 Mainz, Germany
- Shenzhen
Institute of Aggregate Science and Technology, School of Science and
Engineering, The Chinese University of Hong
Kong, Shenzhen 518172, China
| | - Klaus Müllen
- Max
Planck Institute for Polymer Research, Ackermannweg 10, 55128 Mainz, Germany
- Institute
for Physical Chemistry , Johannes Gutenberg
University Mainz, Duesbergweg
10-14, 55128 Mainz, Germany
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19
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Rothschild DA, Kopcha WP, Tran A, Zhang J, Lipke MC. Gram-scale synthesis of a covalent nanocage that preserves the redox properties of encapsulated fullerenes. Chem Sci 2022; 13:5325-5332. [PMID: 35655559 PMCID: PMC9093146 DOI: 10.1039/d2sc00445c] [Citation(s) in RCA: 8] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/24/2022] [Accepted: 04/04/2022] [Indexed: 11/21/2022] Open
Abstract
Discrete nanocages provide a way to solubilize, separate, and tune the properties of fullerenes, but these 3D receptors cannot usually be synthesized easily from inexpensive starting materials, limiting their utility. Herein, we describe the first fullerene-binding nanocage (Cage4+) that can be made efficiently on a gram scale. Cage4+ was prepared in up to 57% yield by the formation of pyridinium linkages between complemantary porphyrin components that are themselves readily accessible. Cage4+ binds C60 and C70 with large association constants (>108 M−1), thereby solubilizing these fullerenes in polar solvents. Fullerene association and redox-properties were subsequently investigated across multiple charge states of the host-guest complexes. Remarkably, neutral and singly reduced fullerenes bind with similar strengths, leaving their 0/1− redox couples minimally perturbed and fully reversible, whereas other hosts substantially alter the redox properties of fullerenes. Thus, C60@Cage4+ and C70@Cage4+ may be useful as solubilized fullerene derivatives that preserve the inherent electron-accepting and electron-transfer capabilities of the fullerenes. Fulleride dianions were also found to bind strongly in Cage4+, while further reduction is centered on the host, leading to lowered association of the fulleride guest in the case of C602−. This report describes the first gram-scale synthesis of a nanocage that can host fullerenes (C60 and C70). The redox properties of the fullerenes are preserved in this host, enabling characterization of complexes with fulleride anions and dianions.![]()
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Affiliation(s)
- Daniel A Rothschild
- Department of Chemistry and Chemical Biology, Rutgers, The State University of New Jersey 123 Bevier Rd Piscataway NJ 08854 USA
| | - William P Kopcha
- Department of Chemistry and Chemical Biology, Rutgers, The State University of New Jersey 123 Bevier Rd Piscataway NJ 08854 USA
| | - Aaron Tran
- Department of Chemistry and Chemical Biology, Rutgers, The State University of New Jersey 123 Bevier Rd Piscataway NJ 08854 USA
| | - Jianyuan Zhang
- Department of Chemistry and Chemical Biology, Rutgers, The State University of New Jersey 123 Bevier Rd Piscataway NJ 08854 USA
| | - Mark C Lipke
- Department of Chemistry and Chemical Biology, Rutgers, The State University of New Jersey 123 Bevier Rd Piscataway NJ 08854 USA
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20
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Harimoto T, Ishigaki Y. Redox‐Active Hydrocarbons: Isolation and Structural Determination of Cationic States toward Advanced Response Systems. Chempluschem 2022; 87:e202200013. [DOI: 10.1002/cplu.202200013] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/17/2022] [Revised: 03/17/2022] [Indexed: 11/12/2022]
Affiliation(s)
- Takashi Harimoto
- Hokkaido University: Hokkaido Daigaku Department of Chemistry, Faculty of Science JAPAN
| | - Yusuke Ishigaki
- Hokkaido University: Hokkaido Daigaku Department of Chemistry, Faculty of Science North 10, West 8, North-ward 060-0810 Sapporo JAPAN
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21
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Vasylevskyi SI, Raffy G, Salentinig S, Del Guerzo A, Fromm KM, Bassani DM. Multifunctional Anthracene-Based Ni-MOF with Encapsulated Fullerenes: Polarized Fluorescence Emission and Selective Separation of C 70 from C 60. ACS APPLIED MATERIALS & INTERFACES 2022; 14:1397-1403. [PMID: 34967204 DOI: 10.1021/acsami.1c19141] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/14/2023]
Abstract
We report an anthracene-based Ni-MOF [Ni(II) metal-organic framework, {[Ni(μ2-L)2Cl2]·x(C6H6)·y(MeOH)}n (1), L = anthracene-9,10-diylbis(methylene)diisonicotinate] whose crystal structure reveals the presence of hexagonal channels with a pore size of 1.4 nm that can accommodate guests such as C60 and C70. Both confocal fluorescence and Raman microscopy results are in agreement with a homogeneous distribution of fullerenes throughout the single crystals of 1. Efficient energy transfer from 1 to the fullerenes was observed, which emitted partially polarized fluorescence emission. Stronger binding between 1 and C70 versus C60 was confirmed from HPLC analysis of the dissolved material and provides a basis for the selective retention of C70 in liquid chromatography columns packed with 1.
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Affiliation(s)
- Serhii I Vasylevskyi
- Chemistry Department, University of Fribourg, Chemin du Musee 9, Fribourg 1700, Switzerland
- University of Bordeaux, ISM CNRS UMR 5255, Talence 33400, France
| | - Guillaume Raffy
- University of Bordeaux, ISM CNRS UMR 5255, Talence 33400, France
| | - Stefan Salentinig
- Chemistry Department, University of Fribourg, Chemin du Musee 9, Fribourg 1700, Switzerland
| | - André Del Guerzo
- University of Bordeaux, ISM CNRS UMR 5255, Talence 33400, France
| | - Katharina M Fromm
- Chemistry Department, University of Fribourg, Chemin du Musee 9, Fribourg 1700, Switzerland
| | - Dario M Bassani
- University of Bordeaux, ISM CNRS UMR 5255, Talence 33400, France
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22
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Liu C, Yang W, Wang C, Liu K, Jiang J. Photophysical Behaviors of Shape-persistent Zinc Porphyrin Organic Cage. NEW J CHEM 2022. [DOI: 10.1039/d2nj00734g] [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
A pair chiral metallic porphyrin cages, (R)/(S)-PTC-1(Zn), have been afforded by pure chiral cyclohexanediamine reacting with zinc 5,15-di[3',5'-diformyl-(1,1'-biphenyl)]porphyrin. Both their chiral tubular structures have been demonstrated with single crystal diffraction...
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23
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Moreno-Simoni M, Torres T, de la Torre G. Subphthalocyanine capsules: molecular reactors for photoredox transformations of fullerenes. Chem Sci 2022; 13:9249-9255. [PMID: 36092995 PMCID: PMC9384690 DOI: 10.1039/d2sc01931k] [Citation(s) in RCA: 9] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/03/2022] [Accepted: 07/19/2022] [Indexed: 12/20/2022] Open
Abstract
The internal cavity formed by a dimeric subphthalocyanine (SubPc) capsule (SubPc2Pd3, 2), ensembled by coordination of pyridyl substituents in the monomeric SubPc 1 to Pd centers, has proved an optimal space for the complexation of C60 fullerene. Taking advantage of the intense absorption of green light of the SubPc component at around 550 nm, we have tested different green-light induced photoredox addition reactions over the double bonds of guest C60. Both addition of amine radicals, generated by reductive quenching of the excited state of 2 by aromatic trimethylsilylamines, and addition of trifluoroethyl radicals, obtained from oxidative quenching of the photosensitizer, have successfully taken place with good yields in the 2:C60 host:guest complex. On the other hand, both the photoredox reactions result in much lower yields when the monomeric pyridyl-SubPc is used as a photocatalyst, demonstrating that encapsulation results in a strong acceleration of the reaction. Importantly, this is the first example of the use of a confined microenvironment to trigger photoredox chemical transformations of fullerenes. A photoredox cage built by coordination of two pyridyl-subphthalocyanines to Pd centers has proved versatile and efficient to catalyze photoredox addition reactions over encapsulated C60.![]()
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Affiliation(s)
- Marta Moreno-Simoni
- Organic Chemistry Department, Universidad Autónoma de Madrid, Campus de Cantoblanco, 28049-Madrid, Spain
| | - Tomás Torres
- Organic Chemistry Department, Universidad Autónoma de Madrid, Campus de Cantoblanco, 28049-Madrid, Spain
- Institute for Advanced Research in Chemical Sciences (IAdChem), Universidad Autónoma de Madrid, Campus de Cantoblanco, 28049-Madrid, Spain
- IMDEA-Nanociencia, C/Faraday 9, 28049-Madrid, Spain
| | - Gema de la Torre
- Organic Chemistry Department, Universidad Autónoma de Madrid, Campus de Cantoblanco, 28049-Madrid, Spain
- Institute for Advanced Research in Chemical Sciences (IAdChem), Universidad Autónoma de Madrid, Campus de Cantoblanco, 28049-Madrid, Spain
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24
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Maiti A, Sobottka S, Chandra S, Jana D, Ravat P, Sarkar B, Jana A. Diamidocarbene-Based Thiele and Tschitschibabin Hydrocarbons: Carbonyl Functionalized Kekulé Diradicaloids. J Org Chem 2021; 86:16464-16472. [PMID: 34780693 DOI: 10.1021/acs.joc.1c01827] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Herein, we report diamidocarbene (DAC)-based Thiele and Tschitschibabin hydrocarbons, diradicaloids that contain four carbonyl/amido functional groups. The impact of two different π-conjugated spacers, p-phenylene vs p,p'-biphenylene, has been realized. The quantum chemical calculations suggest diamidocarbene (DAC)-based Thiele hydrocarbon (p-phenylene bridged) closed-shell singlet is the ground state, whereas for the diamidocarbene (DAC)-based Tschitschibabin hydrocarbon (p,p'-biphenylene bridged), open-shell singlet is the ground state. The influence of two different π-conjugated spacers also has been reflected in their UV-vis spectra. To gain more information on the diamidocarbene (DAC)-based Thiele and Tschitschibabin hydrocarbons, we have also carried out cyclic voltammetry investigations along with UV-vis-NIR-spectroelectrochemical studies of their corresponding 2-e oxidized product.
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Affiliation(s)
- Avijit Maiti
- Tata Institute of Fundamental Research Hyderabad, Gopanpally, Hyderabad 500046, Telangana, India
| | - Sebastian Sobottka
- Institut für Chemie und Biochemie, Anorganische Chemie, Freie Universität Berlin, Fabeckstraße 34-36, 14195 Berlin, Germany
| | - Shubhadeep Chandra
- Institut für Chemie und Biochemie, Anorganische Chemie, Freie Universität Berlin, Fabeckstraße 34-36, 14195 Berlin, Germany.,Universität Stuttgart, Fakultät Chemie, Lehrstuhl für Anorganische Koordinationschemie, Institut für Anorganische Chemie, Pfaffenwaldring 55, 70569 Stuttgart, Germany
| | - Debayan Jana
- Tata Institute of Fundamental Research Hyderabad, Gopanpally, Hyderabad 500046, Telangana, India
| | - Prince Ravat
- Institute of Organic Chemistry, University of Würzburg, Am Hubland, 97074 Würzburg, Germany
| | - Biprajit Sarkar
- Institut für Chemie und Biochemie, Anorganische Chemie, Freie Universität Berlin, Fabeckstraße 34-36, 14195 Berlin, Germany.,Universität Stuttgart, Fakultät Chemie, Lehrstuhl für Anorganische Koordinationschemie, Institut für Anorganische Chemie, Pfaffenwaldring 55, 70569 Stuttgart, Germany
| | - Anukul Jana
- Tata Institute of Fundamental Research Hyderabad, Gopanpally, Hyderabad 500046, Telangana, India
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25
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Mao L, Zhou M, Shi X, Yang HB. Triphenylamine (TPA) radical cations and related macrocycles. CHINESE CHEM LETT 2021. [DOI: 10.1016/j.cclet.2021.05.004] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/08/2023]
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26
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Huang B, Mao L, Shi X, Yang HB. Recent advances and perspectives on supramolecular radical cages. Chem Sci 2021; 12:13648-13663. [PMID: 34760150 PMCID: PMC8549795 DOI: 10.1039/d1sc01618k] [Citation(s) in RCA: 22] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/01/2021] [Accepted: 08/31/2021] [Indexed: 12/20/2022] Open
Abstract
Supramolecular radical chemistry has been emerging as a cutting-edge interdisciplinary field of traditional supramolecular chemistry and radical chemistry in recent years. The purpose of such a fundamental research field is to combine traditional supramolecular chemistry and radical chemistry together, and take the benefit of both to eventually create new molecules and materials. Recently, supramolecular radical cages have been becoming one of the most frontier and challenging research focuses in the field of supramolecular chemistry. In this Perspective, we give a brief introduction to organic radical chemistry, supramolecular chemistry, and the emerging supramolecular radical chemistry along with their history and application. Subsequently, we turn to the main part of this topic: supramolecular radical cages. The design and synthesis of supramolecular cages consisting of redox-active building blocks and radical centres are summarized. The host-guest interactions between supramolecular (radical) cages and organic radicals are also surveyed. Some interesting properties and applications of supramolecular radical cages such as their unique spin-spin interactions and intriguing confinement effects in radical-mediated/catalyzed reactions are comprehensively discussed and highlighted in the main text. The purpose of this Perspective is to help students and researchers understand the development of supramolecular radical cages, and potentially to stimulate innovation and creativity and infuse new energy into the fields of traditional supramolecular chemistry and radical chemistry as well as supramolecular radical chemistry.
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Affiliation(s)
- Bin Huang
- Shanghai Key Laboratory of Green Chemistry and Chemical Processes, School of Chemistry and Molecular Engineering, East China Normal University 3663 N. Zhongshan Road Shanghai 200062 P. R. China
| | - Lijun Mao
- Shanghai Key Laboratory of Green Chemistry and Chemical Processes, School of Chemistry and Molecular Engineering, East China Normal University 3663 N. Zhongshan Road Shanghai 200062 P. R. China
| | - Xueliang Shi
- Shanghai Key Laboratory of Green Chemistry and Chemical Processes, School of Chemistry and Molecular Engineering, East China Normal University 3663 N. Zhongshan Road Shanghai 200062 P. R. China
| | - Hai-Bo Yang
- Shanghai Key Laboratory of Green Chemistry and Chemical Processes, School of Chemistry and Molecular Engineering, East China Normal University 3663 N. Zhongshan Road Shanghai 200062 P. R. China
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Míguez‐Lago S, Gliemann BD, Kivala M, Cid MM. A Chiral Molecular Cage Comprising Diethynylallenes and N-Heterotriangulenes for Enantioselective Recognition. Chemistry 2021; 27:13352-13357. [PMID: 34374138 PMCID: PMC8518621 DOI: 10.1002/chem.202101801] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/21/2021] [Indexed: 12/05/2022]
Abstract
Chirality, a characteristic tool of molecular recognition in nature, is often a complement of redox active systems. Scientists, in their eagerness to mimic such sophistication, have designed numerous chiral systems based on molecular entities with cavities, such as macrocycles and cages. In an attempt to combine chirality and redox-active species, in this contribution we report the synthesis and detailed characterization of a chiral shape-persistent molecular cage based on the combination of enantiopure diethynylallenes and electron-rich bridged triarylamines, also known as N-heterotriangulenes. Its ability for chiral recognition in solution was revealed through UV/vis titrations with enantiopure helicenes.
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Affiliation(s)
- Sandra Míguez‐Lago
- Departamento de Química OrgánicaUniversidade de VigoCampus Lagoas-Marcosende36310VigoSpain
- Department of Chemistry and PharmacyChair of Organic Chemistry IFriedrich-Alexander-Universität Erlangen-NürnbergNikolaus-Fiebiger-Str. 1091058ErlangenGermany
| | - Bettina D. Gliemann
- Department of Chemistry and PharmacyChair of Organic Chemistry IFriedrich-Alexander-Universität Erlangen-NürnbergNikolaus-Fiebiger-Str. 1091058ErlangenGermany
| | - Milan Kivala
- Organisch-Chemisches InstitutRuprecht-Karls-Universität HeidelbergIm Neuenheimer Feld 27069120HeidelbergGermany
- Centre for Advanced MaterialsRuprecht-Karls-Universität HeidelbergIm Neuenheimer Feld 22569120HeidelbergGermany
| | - María Magdalena Cid
- Departamento de Química OrgánicaUniversidade de VigoCampus Lagoas-Marcosende36310VigoSpain
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28
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Zhu J, Han Y, Ni Y, Wu S, Zhang Q, Jiao T, Li Z, Wu J. Facile Synthesis of a Fully Fused, Three-Dimensional π-Conjugated Archimedean Cage with Magnetically Shielded Cavity. J Am Chem Soc 2021; 143:14314-14321. [PMID: 34455792 DOI: 10.1021/jacs.1c06490] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022]
Abstract
The synthesis of molecular cages consisting of fully fused, π-conjugated rings is rare due to synthetic challenges including preorganization, large strain, and poor solubility. Herein, we report such an example in which a tris-2-aminobenzophenone precursor undergoes acid-mediated self-condensation to form a truncated tetrahedron, one of the 13 Archimedean solids. Formation of eight-membered [1,5]diazocine rings provides preorganization and releases the strain while still maintains weak π-conjugation of the backbone. Thorough characterizations were performed by X-ray, NMR, and UV-vis analysis, assisted by theoretical calculations. The cage exhibits a rigid backbone structure with a well-defined cavity that confines a magnetically shielded environment. The solvent molecule, o-dichlorobenzene, is precisely encapsulated in the cavity at a 1:1 ratio with multiple π···π, C-H···π, and halogen···π interactions with the cage skeleton, implying its template effect for the cage closing reaction. Our synthetic strategy opens the opportunity to access more complex, fully fused, three-dimensional π-conjugated cages.
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Affiliation(s)
- Jun Zhu
- Department of Chemistry, National University of Singapore, Singapore 117543
| | - Yi Han
- Department of Chemistry, National University of Singapore, Singapore 117543
| | - Yong Ni
- Department of Chemistry, National University of Singapore, Singapore 117543
| | - Shaofei Wu
- Department of Chemistry, National University of Singapore, Singapore 117543
| | - Qiuyu Zhang
- Department of Chemistry, National University of Singapore, Singapore 117543.,Joint School of National University of Singapore and Tianjin University, International Campus of Tianjin University, Fuzhou 350207, China
| | - Tianyu Jiao
- Department of Chemistry, National University of Singapore, Singapore 117543
| | - Zhengtao Li
- Department of Chemistry, National University of Singapore, Singapore 117543
| | - Jishan Wu
- Department of Chemistry, National University of Singapore, Singapore 117543.,Joint School of National University of Singapore and Tianjin University, International Campus of Tianjin University, Fuzhou 350207, China
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29
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Zhu C, Poater A, Duhayon C, Kauffmann B, Saquet A, Rives A, Maraval V, Chauvin R. Carbo-mer of Barrelene: A Rigid 3D-Carbon-Expanded Molecular Barrel. Chemistry 2021; 27:9286-9291. [PMID: 33900649 DOI: 10.1002/chem.202100670] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/23/2021] [Indexed: 11/08/2022]
Abstract
After extensive studies of 1D and 2D skeletal carbo-mers based on C8 π-conjugating dialkynylbutatriene units (DABs: ∼C≡C-(R)C=C=C=C(R)-C≡C∼) bridging sp or sp2 centers in carbo-butene, carbo-xylylene or carbo-benzene derivatives, 3D versions are envisaged through carbo-barrelenes and partially reduced derivatives thereof where two or three DAB blades span a bridge between sp3 carbinol vertices or ether thereof. For R=Ph, stable representatives were synthesized through a pivotal [6]pericyclynedione, and extensively characterized by spectroscopic, electrochemical and crystallographic methods. Density functional theory calculations allow detailed analysis of structural and electronic features of the 7 Å high C26 barrel-shaped molecules, and show that they can behave as cages for ionic species. Beyond aesthetical concerns, the results could open prospects of applications in host-guest supramolecular chemistry and single molecule charge transport.
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Affiliation(s)
- Chongwei Zhu
- LCC-CNRS, University of Toulouse, 205 route de Narbonne, 31077, Toulouse, France
| | - Albert Poater
- Institut de Química Computacional i Catàlisi and, Departament de Química, Universitat de Girona, c/ Maria Aurèlia Capmany 69, 17003, Girona, Catalonia, Spain
| | - Carine Duhayon
- LCC-CNRS, University of Toulouse, 205 route de Narbonne, 31077, Toulouse, France
| | - Brice Kauffmann
- CNRS, INSERM, UMS3033/US001, Institut Européen de Chimie Biologie, Université de Bordeaux, 33607, Pessac, France
| | - Alix Saquet
- LCC-CNRS, University of Toulouse, 205 route de Narbonne, 31077, Toulouse, France
| | - Arnaud Rives
- LCC-CNRS, University of Toulouse, 205 route de Narbonne, 31077, Toulouse, France
| | - Valérie Maraval
- LCC-CNRS, University of Toulouse, 205 route de Narbonne, 31077, Toulouse, France
| | - Remi Chauvin
- LCC-CNRS, University of Toulouse, 205 route de Narbonne, 31077, Toulouse, France
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Ishigaki Y, Harimoto T, Sugawara K, Suzuki T. Hysteretic Three-State Redox Interconversion among Zigzag Bisquinodimethanes with Non-fused Benzene Rings and Twisted Tetra-/Dications with [5]/[3]Acenes Exhibiting Near-Infrared Absorptions. J Am Chem Soc 2021; 143:3306-3311. [PMID: 33636078 DOI: 10.1021/jacs.1c00189] [Citation(s) in RCA: 13] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Octaaryl-substituted bisquinodimethanes (BQDs) with a zigzag structure were designed as redox-switchable molecules that undergo four-electron oxidation to produce tetracationic pentacenes with a doubly twisted structure. In contrast to one-stage four-electron oxidation of BQDs, stepwise two-electron reduction of tetracationic pentacenes occurs to give dicationic anthracenes and then the original BQDs, step-by-step. Since both tetracations and dications exhibit near-infrared (NIR) absorptions (-1400 nm) based on an intramolecular charge-transfer interaction, changes in not only their structures but also their UV-vis-NIR spectra can be controlled by redox stimuli. In this Communication, we present an unprecedented one-step π-extension to pentacene from non-fused benzene rings by oxidation, and subsequent two-stage deannulation to benzene rings via anthracene upon reduction. All structures were determined by single-crystal X-ray analyses, and their properties were characterized by spectroscopic and theoretical studies.
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Affiliation(s)
- Yusuke Ishigaki
- Department of Chemistry, Faculty of Science, Hokkaido University, Sapporo 060-0810, Japan
| | - Takashi Harimoto
- Department of Chemistry, Faculty of Science, Hokkaido University, Sapporo 060-0810, Japan
| | - Kazuma Sugawara
- Department of Chemistry, Faculty of Science, Hokkaido University, Sapporo 060-0810, Japan
| | - Takanori Suzuki
- Department of Chemistry, Faculty of Science, Hokkaido University, Sapporo 060-0810, Japan
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32
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Liao F, Huang W, Chen B, Ding Z, Li X, Su H, Wang T, Wang Y, Miao H, Zhang X, Luo Y, Yang J, Zhang G. Are pyridinium ylides radicals? Chem Commun (Camb) 2020; 56:11287-11290. [PMID: 32839790 DOI: 10.1039/d0cc04604c] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Pyridinium ylides are usually considered nucleophiles that can undergo various reactions involving electron pairs. However, it was found that ylides resulting from deprotonation of N-alkyl-substituted pyridinium salts exhibit radical characters, with no discernable NMR signals but decent EPR spectra in both solution and the solid state. An observed correlation between lowered π* energy level of the pyridinium ring and increased EPR activity indicates that thermally induced electron-transfer processes could be involved, where the variable-temperature EPR spectrum indicates a singlet ground state and a thermally activated triplet state for the ylide. The fact that the high-resolution mass spectrum confirms the presence of oligomers of a less sterically hindered pyridinium ylide further points to a radical mechanism.
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Affiliation(s)
- Fan Liao
- Hefei National Laboratory for Physical Sciences at the Microscale, University of Science and Technology of China, Hefei, Anhui 230026, China.
| | - Wenhuan Huang
- Hefei National Laboratory for Physical Sciences at the Microscale, University of Science and Technology of China, Hefei, Anhui 230026, China.
| | - Biao Chen
- Hefei National Laboratory for Physical Sciences at the Microscale, University of Science and Technology of China, Hefei, Anhui 230026, China.
| | - Zijing Ding
- Hefei National Laboratory for Physical Sciences at the Microscale, University of Science and Technology of China, Hefei, Anhui 230026, China.
| | - Xingxing Li
- Hefei National Laboratory for Physical Sciences at the Microscale, University of Science and Technology of China, Hefei, Anhui 230026, China.
| | - Hao Su
- Hefei National Laboratory for Physical Sciences at the Microscale, University of Science and Technology of China, Hefei, Anhui 230026, China.
| | - Tao Wang
- Hefei National Laboratory for Physical Sciences at the Microscale, University of Science and Technology of China, Hefei, Anhui 230026, China.
| | - Yucai Wang
- Hefei National Laboratory for Physical Sciences at the Microscale, University of Science and Technology of China, Hefei, Anhui 230026, China.
| | - Hui Miao
- Hefei National Laboratory for Physical Sciences at the Microscale, University of Science and Technology of China, Hefei, Anhui 230026, China.
| | - Xiaolong Zhang
- Hefei National Laboratory for Physical Sciences at the Microscale, University of Science and Technology of China, Hefei, Anhui 230026, China.
| | - Yi Luo
- Hefei National Laboratory for Physical Sciences at the Microscale, University of Science and Technology of China, Hefei, Anhui 230026, China.
| | - Jinlong Yang
- Hefei National Laboratory for Physical Sciences at the Microscale, University of Science and Technology of China, Hefei, Anhui 230026, China.
| | - Guoqing Zhang
- Hefei National Laboratory for Physical Sciences at the Microscale, University of Science and Technology of China, Hefei, Anhui 230026, China.
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