1
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Mu Y, Dai Y, Ruiz DA, Liu LL, Xu LP, Tung CH, Kong L. Aromatic 1,4,2,3-Diazadiborole Featuring an Unsymmetrical B=B Entity: A Versatile Synthon for Unusual Boron Heterocycles. Angew Chem Int Ed Engl 2024:e202405905. [PMID: 38771269 DOI: 10.1002/anie.202405905] [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: 03/27/2024] [Revised: 05/21/2024] [Accepted: 05/21/2024] [Indexed: 05/22/2024]
Abstract
The replacement of a CC unit with an isoelectronic BN unit in aromatic systems can give rise to molecules and materials with fascinating properties. We report here the synthesis, characterization, and reactivity of a 1,4,2,3-diazadiborole species, 2, featuring an unprecedented 6π-aromatic BN-heterocyclic moiety that is isoelectronic to cyclopentadienide (Cp-). Bearing an unsymmetrical B=B entity, 2 exhibits reactivity toward oxidants, protic reagents, electrophiles, and unsaturated substrates. This reactivity facilitates the synthesis of a variety of novel mono- and bicyclic organoboron derivatives through mechanisms including ring retention, cleavage/recombination, annulation, and expansion. These findings reveal innovative synthetic routes to BN-embedded aromatic compounds via desymmetrization, affording unique building blocks for synthetic chemistry.
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Affiliation(s)
- Yu Mu
- School of Chemistry and Chemical Engineering, Shandong University, Jinan, 250100, China
| | - Yuyang Dai
- School of Chemistry and Chemical Engineering, Shandong University, Jinan, 250100, China
| | - David A Ruiz
- Department of Chemistry and Research Center for Chemical Biology and Omics Analysis, College of Science, Southern University of Science and Technology, Shenzhen, 518055, China
| | - Liu Leo Liu
- Department of Chemistry and Research Center for Chemical Biology and Omics Analysis, College of Science, Southern University of Science and Technology, Shenzhen, 518055, China
| | - Li-Ping Xu
- School of Chemistry and Chemical Engineering, Shandong University, Jinan, 250100, China
| | - Chen-Ho Tung
- School of Chemistry and Chemical Engineering, Shandong University, Jinan, 250100, China
| | - Lingbing Kong
- School of Chemistry and Chemical Engineering, Shandong University, Jinan, 250100, China
- State Key Laboratory of Elemento-Organic Chemistry, Nankai University, Tianjin, 300071, China
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2
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Heinz M, Arrowsmith M, Schweizer JI, Krummenacher I, Holthausen MC, Braunschweig H. Experimental and Computational Study of a Confirmed Borylene-to-Diborene Dimerization. J Am Chem Soc 2023; 145:22685-22696. [PMID: 37802099 DOI: 10.1021/jacs.3c07979] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/08/2023]
Abstract
While the dimerization of heavier group 13 carbene analogues to the corresponding alkene analogues is known and relatively well understood, the dimerization of dicoordinate borylenes (LRB:, L = neutral donor; R = anionic substituent) to the corresponding diborenes (LRB═BRL) has never been directly observed. In this study we present the first example of a formal borylene-to-diborene dimerization through abstraction of a labile phosphine ligand from the tricoordinate hydroborylene precursor (CAAC)(Me3P)BH (CAAC = cyclic alkyl(amino)carbene) by bulky Lewis-acidic dihaloboranes (BX2Y, X = Cl, Br, Y = aryl, boryl), generating the corresponding dihydrodiborene (CAAC)HB═BH(CAAC) and (Me3P)BX2Y as the byproduct. An in-depth experimental and computational mechanistic analysis shows that this seemingly simple process (2 LL'BH + 2 BX2Y → LHB═BHL + 2 L'BX2Y) is in fact based on a complex sequence of finely tuned processes, involving the one-electron oxidation of and PMe3 abstraction from the borylene precursor by BX2Y, multiple halide transfers between (di)boron intermediates and BX2Y/[BX3Y]-, and multiple one-electron redox processes between diboron intermediates and the borylene precursor, which make the reaction ultimately autocatalytic in [(CAAC)(Me3P)BH]•+. The findings suggest that [LBXR]• boryl radicals are more likely coupling partners than dicoordinate LRB: borylenes in the reductive coupling of base-stabilized LBX2R boranes to LRB═BRL diborenes.
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Affiliation(s)
- Myron Heinz
- Institute for Inorganic and Analytical Chemistry, Goethe-Universität Frankfurt am Main, Max-von-Laue-Straße 7, 60438 Frankfurt am Main, Germany
| | - Merle Arrowsmith
- Institute for Inorganic Chemistry, Julius-Maximilians-Universität Würzburg, Am Hubland, 97074 Würzburg, Germany
- Institute for Sustainable Chemistry & Catalysis with Boron, Julius-Maximilians-Universität Würzburg, Am Hubland, 97074 Würzburg, Germany
| | - Julia I Schweizer
- Institute for Inorganic and Analytical Chemistry, Goethe-Universität Frankfurt am Main, Max-von-Laue-Straße 7, 60438 Frankfurt am Main, Germany
| | - Ivo Krummenacher
- Institute for Inorganic Chemistry, Julius-Maximilians-Universität Würzburg, Am Hubland, 97074 Würzburg, Germany
- Institute for Sustainable Chemistry & Catalysis with Boron, Julius-Maximilians-Universität Würzburg, Am Hubland, 97074 Würzburg, Germany
| | - Max C Holthausen
- Institute for Inorganic and Analytical Chemistry, Goethe-Universität Frankfurt am Main, Max-von-Laue-Straße 7, 60438 Frankfurt am Main, Germany
| | - Holger Braunschweig
- Institute for Inorganic Chemistry, Julius-Maximilians-Universität Würzburg, Am Hubland, 97074 Würzburg, Germany
- Institute for Sustainable Chemistry & Catalysis with Boron, Julius-Maximilians-Universität Würzburg, Am Hubland, 97074 Würzburg, Germany
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3
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Fan J, Koh AP, Zhou J, Zhang ZF, Wu CS, Webster RD, Su MD, So CW. Tetrakis( N-heterocyclic Carbene)-Diboron(0): Double Single-Electron-Transfer Reactivity. J Am Chem Soc 2023; 145:11669-11677. [PMID: 37201187 DOI: 10.1021/jacs.3c01801] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/20/2023]
Abstract
The use of 1,3,4,5-tetramethylimidazol-2-ylidene (IMe) to coordinate with diatomic B2 species afforded a tetrakis(N-heterocyclic carbene)-diboron(0) [(IMe)2B-B(IMe)2] (2). The singly bonded B2 moiety therein possesses a valence electronic configuration 1σg21πu21πg*2 with four vacant molecular orbitals (1σu*, 2σg, 1πu', 1πg'*) coordinated with IMe. Its unprecedented electronic structure is analogous to the energetically unfavorable planar hydrazine with a D2h symmetry. The two highly reactive πg* antibonding electrons enable double single-electron-transfer (SET) reactivity in small-molecule activation. Compound 2 underwent a double SET reduction with CO2 to form two carbon dioxide radical anions CO2•-, which then reduced pyridine to yield a carboxylated pyridine reductive coupling dianion [O2CNC5(H)5-C5(H)5NCO2]2- and converted compound 2 to the tetrakis(N-heterocyclic carbene)-diborene dication [(IMe)2B═B(IMe)2]2+ (32+). This is a remarkable transition-metal-free SET reduction of CO2 without ultraviolet/visible (UV/vis) light conditions.
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Affiliation(s)
- Jun Fan
- School of Chemistry, Chemical Engineering and Biotechnology, Nanyang Technological University, 637371 Singapore
| | - An-Ping Koh
- School of Chemistry, Chemical Engineering and Biotechnology, Nanyang Technological University, 637371 Singapore
| | - Jingsong Zhou
- School of Chemistry, Chemical Engineering and Biotechnology, Nanyang Technological University, 637371 Singapore
| | - Zheng-Feng Zhang
- Department of Applied Chemistry, National Chiayi University, Chiayi 60004, Taiwan
| | - Chi-Shiun Wu
- Department of Applied Chemistry, National Chiayi University, Chiayi 60004, Taiwan
| | - Richard D Webster
- School of Chemistry, Chemical Engineering and Biotechnology, Nanyang Technological University, 637371 Singapore
| | - Ming-Der Su
- Department of Applied Chemistry, National Chiayi University, Chiayi 60004, Taiwan
- Department of Medicinal and Applied Chemistry, Kaohsiung Medical University, Kaohsiung 80708, Taiwan
| | - Cheuk-Wai So
- School of Chemistry, Chemical Engineering and Biotechnology, Nanyang Technological University, 637371 Singapore
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4
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Tang C, Song L, Zhou K, Ren P, Zhao E, He Z. Manipulating D-A interaction to achieve stable photoinduced organic radicals in triphenylphosphine crystals. Chem Sci 2023; 14:1871-1877. [PMID: 36819874 PMCID: PMC9930928 DOI: 10.1039/d2sc05753k] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/17/2022] [Accepted: 01/18/2023] [Indexed: 01/19/2023] Open
Abstract
New strategies for the design and synthesis of stable organic radicals without additives are highly desirable. Herein, we design a series of donor-acceptor structured triarylphosphines and disclose the fast color change triggered by UV-irradiation in the crystalline state. Photoinduced organic radicals are undoubtedly verified and proved to be the reason for the color change by time-dependent and quantitative electron paramagnetic resonance analysis, X-ray crystallographic analysis, and theoretical calculations. It is revealed that the intrinsic symmetry breaking of peripheral architecture helps to form continuous molecular chains by donor-acceptor counterpart pairing. Intermolecular electron-transfer occurs among molecular chains and results in radical ion pairs upon photoirradiation.
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Affiliation(s)
- Chunlin Tang
- School of Science, Harbin Institute of Technology Shenzhen Guangdong 518055 China
| | - Lijuan Song
- School of Science, Harbin Institute of Technology Shenzhen Guangdong 518055 China
| | - Kang Zhou
- Hoffmann Institute of Advanced Materials, Shenzhen PolytechnicShenzhenGuangdong 518055China
| | - Peng Ren
- School of Science, Harbin Institute of Technology Shenzhen Guangdong 518055 China
| | - Engui Zhao
- School of Science, Harbin Institute of Technology Shenzhen Guangdong 518055 China
| | - Zikai He
- School of Science, Harbin Institute of Technology Shenzhen Guangdong 518055 China .,School of Chemical Engineering and Technology, Harbin Institute of Technology Harbin Heilongjiang 150001 China
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5
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Bennaamane S, Rialland B, Khrouz L, Fustier-Boutignon M, Bucher C, Clot E, Mézailles N. Ammonia Synthesis at Room Temperature and Atmospheric Pressure from N 2 : A Boron-Radical Approach. Angew Chem Int Ed Engl 2023; 62:e202209102. [PMID: 36301016 PMCID: PMC10107438 DOI: 10.1002/anie.202209102] [Citation(s) in RCA: 10] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/21/2022] [Revised: 09/09/2022] [Accepted: 10/24/2022] [Indexed: 11/06/2022]
Abstract
Ammonia, NH3 , is an essential molecule, being part of fertilizers. It is currently synthesized via the Haber-Bosch process, from the very stable dinitrogen molecule, N2 and dihydrogen, H2 . This process requires high temperatures and pressures, thereby generating ca 1.6 % of the global CO2 emissions. Alternative strategies are needed to realize the functionalization of N2 to NH3 under mild conditions. Here, we show that boron-centered radicals provide a means of activating N2 at room temperature and atmospheric pressure whilst allowing a radical process to occur, leading to the production of borylamines. Subsequent hydrolysis released NH4 + , the acidic form of NH3 . EPR spectroscopy supported the intermediacy of radicals in the process, corroborated by DFT calculations, which rationalized the mechanism of the N2 functionalization by R2 B radicals.
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Affiliation(s)
- Soukaina Bennaamane
- Laboratoire Hétérochimie Fondamentale et Appliquée, Université Paul Sabatier, CNRS, 118 Route de Narbonne, 31062, Toulouse, France
| | - Barbara Rialland
- Laboratoire Hétérochimie Fondamentale et Appliquée, Université Paul Sabatier, CNRS, 118 Route de Narbonne, 31062, Toulouse, France
| | - Lhoussain Khrouz
- Univ Lyon, ENS Lyon, CNRS, Universite Lyon 1, Laboratoire de Chimie, UMR 5182, 46 allée d'Italie, 69364, Lyon, France
| | - Marie Fustier-Boutignon
- Laboratoire Hétérochimie Fondamentale et Appliquée, Université Paul Sabatier, CNRS, 118 Route de Narbonne, 31062, Toulouse, France
| | - Christophe Bucher
- Univ Lyon, ENS Lyon, CNRS, Universite Lyon 1, Laboratoire de Chimie, UMR 5182, 46 allée d'Italie, 69364, Lyon, France
| | - Eric Clot
- ICGM, Univ. Montpellier, CNRS, ENSCM, 34000, Montpellier, France
| | - Nicolas Mézailles
- Laboratoire Hétérochimie Fondamentale et Appliquée, Université Paul Sabatier, CNRS, 118 Route de Narbonne, 31062, Toulouse, France
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6
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Zhang H, Wang Y, Lu Q, Song J, Duan Y, Zeng Y, Mo Y. Captodative Effect Facilitates the Excitation in Diboron Molecule (CAAC) 2 B 2 (SH) 2. Chemistry 2023; 29:e202203817. [PMID: 36624078 DOI: 10.1002/chem.202203817] [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: 12/06/2022] [Revised: 01/09/2023] [Accepted: 01/09/2023] [Indexed: 01/11/2023]
Abstract
Given the extraordinary versatility in chemical reactions and applications, boron compounds have gained increasing attentions in the past two decades. One of the remarkable advances is the unprecedented preparation of unsaturated boron species. Notably, Braunschweig et al. found that the cyclic (alkyl)(amino) carbenes (CAACs) stabilized diboron molecules (CAAC)2 B2 (SR)2 host unpaired electrons and exist in the 90°-twisted diradical form, while other analogues, such as N-heterocyclic carbenes (NHCs), stabilized diboron molecules prefer a conventional B=B double bond. Since previous studies recognized the differences in the steric effect between CAAC and NHC carbenes, here we focused on the role of thiol substituents in (CAAC)2 B2 (SR)2 by gradually localizing involved electrons. The co-planarity of the thiol groups and the consequent captodative effect were found to be the culprit for the 90°-twisted diradical form of (CAAC)2 B2 (SR)2 . Computational analyses identified two forces contributing to the π electron movements. One is the "push" effect of lone pairs on the sulfur atoms which boosts the π electron delocalization between the BB center and CAACs. The other is the π electron delocalization within each (CAAC)B(SR) fragment where the pull effect originates from the π electron withdrawal by CAACs. There are two such independent and orthogonal push-pull channels which function mainly in individual (CAAC)B(SR) fragments. This enhanced π push-pull effect in the triplet state facilitates the electronic excitation in (CAAC)2 B2 (SR)2 by reducing the singlet-triplet gap.
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Affiliation(s)
- Huaiyu Zhang
- Institute of Computational Quantum Chemistry, College of Chemistry and Materials Science, Hebei Normal University, Shijiazhuang, 050024, China
| | - Yating Wang
- Institute of Computational Quantum Chemistry, College of Chemistry and Materials Science, Hebei Normal University, Shijiazhuang, 050024, China
| | - Qingrui Lu
- Institute of Computational Quantum Chemistry, College of Chemistry and Materials Science, Hebei Normal University, Shijiazhuang, 050024, China
| | - Jinshuai Song
- Green Catalysis Center, and College of Chemistry, Zhengzhou University, Zhengzhou, 450001, China
| | - Yandong Duan
- Hebei Key Laboratory of Photoelectric Control on Surface and Interface, School of Sciences, Hebei University of Science and Technology, Shijiazhuang, 050018, China
| | - Yanli Zeng
- Institute of Computational Quantum Chemistry, College of Chemistry and Materials Science, Hebei Normal University, Shijiazhuang, 050024, China
| | - Yirong Mo
- Department of Nanoscience, Joint School of Nanoscience and Nanoengineering, University of North Carolina at Greensboro, Greensboro, NC 27401, USA
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7
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Lin YJ, Liu WC, Liu YH, Lee GH, Chien SY, Chiu CW. A linear Di-coordinate boron radical cation. Nat Commun 2022; 13:7051. [PMCID: PMC9671878 DOI: 10.1038/s41467-022-34900-7] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/15/2022] [Accepted: 11/10/2022] [Indexed: 11/19/2022] Open
Abstract
AbstractThe pursuit of di-coordinate boron radical has been continued for more than a half century, and their stabilization and structural characterization remains a challenge. Here we report the isolation and structural characterization of a linear di-coordinate boron radical cation, achieved by stabilizing the two reactive atomic orbitals of the central boron atom by two orthogonal π-donating and π-accepting functionalities. The electron deficient radical cation undergoes facile one-electron reduction to borylene and binds Lewis base to give heteroleptic tri-coordinate boron radical cation. The co-existence of half-filled and empty p orbitals at boron also allows the CO-regulated electron transfer to be explored. As the introduction of CO promotes the electron transfer from a tri-coordinate neutral boron radical to a boron radical cation, the removal of CO under vacuum furnishes the reverse electron transfer from borylene to yield a solution consisting of two boron radicals.
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8
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Kundu G, Balayan K, Tothadi S, Sen SS. Six-Membered Saturated NHC-Stabilized Borenium Cations: Isolation of a Cationic Analogue of Borinic Acid. Inorg Chem 2022; 61:12991-12997. [PMID: 35930736 DOI: 10.1021/acs.inorgchem.2c00611] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
The reaction of six-membered saturated NHC [1,3-di(2,6-diisopropylphenyl) tetrahydropyrimidine-2-ylidene; henceforth abbreviated as 6-SIDipp] with PhBCl2 yields a Lewis base adduct, 6-SIDipp·PhBCl2 (1), which readily undergoes nucleophilic substitution reaction with AgNO3, leading to the single (2) and double (3) substitution of both chlorides with ONO2 moieties at the boron atom. The reaction of 1 with 1 equiv of AlCl3 resulted in a borenium cation of composition [6-SIDipp·B(Ph)Cl]+ (4) with AlCl4- as the counteranion. Although borenium cations with different substituents on boron have been reported, a structurally characterized phenylchloroborenium cation remains unknown. Similarly, the reaction of 1 with triflic acid provides the first representative of a new class of borenium cations bearing one hydroxyl and one phenyl group on boron (5), a cationic analogue of borinic acid.
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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
| | - Kajal Balayan
- 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
| | - Srinu Tothadi
- Analytical and Environmental Sciences Division and Centralized Instrumentation Facility, CSIR-Central Salt and Marine Chemicals Research Institute, Gijubhai Badheka Marg, Bhavnagar 364002, India.,Academy of Scientific and Innovative Research (AcSIR), Ghaziabad 201002, 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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Lu W, Jayaraman A, Fantuzzi F, Dewhurst RD, Härterich M, Dietz M, Hagspiel S, Krummenacher I, Hammond K, Cui J, Braunschweig H. Ein unsymmetrisches, cyclisches Diboren basierend auf einem chelatisierenden CAAC‐Liganden sowie dessen Aktivierung kleiner Moleküle und Umlagerungsreaktionen. Angew Chem Int Ed Engl 2022. [DOI: 10.1002/ange.202113947] [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)
- Wei Lu
- Institut für Anorganische Chemie Julius-Maximilians-Universität Würzburg Am Hubland 97074 Würzburg Deutschland
- Institut für nachhaltige Chemie & Katalyse mit Bor Julius-Maximilians-Universität Würzburg Am Hubland 97074 Würzburg Deutschland
- Key Laboratory of Green Chemistry & Technology of Ministry of Education College of Chemistry Sichuan University 29 Wangjiang Road Chengdu 610064 P. R. China
| | - Arumugam Jayaraman
- Institut für Anorganische Chemie Julius-Maximilians-Universität Würzburg Am Hubland 97074 Würzburg Deutschland
- Institut für nachhaltige Chemie & Katalyse mit Bor Julius-Maximilians-Universität Würzburg Am Hubland 97074 Würzburg Deutschland
| | - Felipe Fantuzzi
- Institut für Anorganische Chemie Julius-Maximilians-Universität Würzburg Am Hubland 97074 Würzburg Deutschland
- Institut für nachhaltige Chemie & Katalyse mit Bor Julius-Maximilians-Universität Würzburg Am Hubland 97074 Würzburg Deutschland
- School of Physical Sciences Ingram Building University of Kent Park Wood Road Canterbury CT2 7NH United Kingdom
| | - Rian D. Dewhurst
- Institut für Anorganische Chemie Julius-Maximilians-Universität Würzburg Am Hubland 97074 Würzburg Deutschland
- Institut für nachhaltige Chemie & Katalyse mit Bor Julius-Maximilians-Universität Würzburg Am Hubland 97074 Würzburg Deutschland
| | - Marcel Härterich
- Institut für Anorganische Chemie Julius-Maximilians-Universität Würzburg Am Hubland 97074 Würzburg Deutschland
- Institut für nachhaltige Chemie & Katalyse mit Bor Julius-Maximilians-Universität Würzburg Am Hubland 97074 Würzburg Deutschland
| | - Maximilian Dietz
- Institut für Anorganische Chemie Julius-Maximilians-Universität Würzburg Am Hubland 97074 Würzburg Deutschland
- Institut für nachhaltige Chemie & Katalyse mit Bor Julius-Maximilians-Universität Würzburg Am Hubland 97074 Würzburg Deutschland
| | - Stephan Hagspiel
- Institut für Anorganische Chemie Julius-Maximilians-Universität Würzburg Am Hubland 97074 Würzburg Deutschland
- Institut für nachhaltige Chemie & Katalyse mit Bor Julius-Maximilians-Universität Würzburg Am Hubland 97074 Würzburg Deutschland
| | - Ivo Krummenacher
- Institut für Anorganische Chemie Julius-Maximilians-Universität Würzburg Am Hubland 97074 Würzburg Deutschland
- Institut für nachhaltige Chemie & Katalyse mit Bor Julius-Maximilians-Universität Würzburg Am Hubland 97074 Würzburg Deutschland
| | - Kai Hammond
- Institut für Anorganische Chemie Julius-Maximilians-Universität Würzburg Am Hubland 97074 Würzburg Deutschland
- Institut für nachhaltige Chemie & Katalyse mit Bor Julius-Maximilians-Universität Würzburg Am Hubland 97074 Würzburg Deutschland
| | - Jingjing Cui
- Institut für Anorganische Chemie Julius-Maximilians-Universität Würzburg Am Hubland 97074 Würzburg Deutschland
- Institut für nachhaltige Chemie & Katalyse mit Bor Julius-Maximilians-Universität Würzburg Am Hubland 97074 Würzburg Deutschland
| | - Holger Braunschweig
- Institut für Anorganische Chemie Julius-Maximilians-Universität Würzburg Am Hubland 97074 Würzburg Deutschland
- Institut für nachhaltige Chemie & Katalyse mit Bor Julius-Maximilians-Universität Würzburg Am Hubland 97074 Würzburg Deutschland
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10
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Xu J, Xu X, Li D, Jian J. Spectroscopic Characterization of Two Boron Heterocyclic Radicals in the Solid Neon Matrix. Phys Chem Chem Phys 2022; 24:7961-7968. [DOI: 10.1039/d2cp00076h] [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
Two novel boron heterocyclic radicals, 3,4,5-trihydroborinine radical and 1-methyl-2-dihydro-1H-borole radical, were observed in the reaction of boron atom with cyclopentene. These radicals were trapped in solid neon and identified by...
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11
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A crystalline radical cation derived from Thiele's hydrocarbon with redox range beyond 1 V. Nat Commun 2021; 12:7052. [PMID: 34862371 PMCID: PMC8642399 DOI: 10.1038/s41467-021-27104-y] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/08/2021] [Accepted: 11/03/2021] [Indexed: 02/07/2023] Open
Abstract
Thiele’s hydrocarbon occupies a central role as an open-shell platform for new organic materials, however little is known about its redox behaviour. While recent synthetic approaches involving symmetrical carbene substitution of the CPh2 termini yield isolable neutral/dicationic analogues, the intervening radical cations are much more difficult to isolate, due to narrow compatible redox ranges (typically < 0.25 V). Here we show that a hybrid BN/carbene approach allows access to an unsymmetrical analogue of Thiele’s hydrocarbon 1, and that this strategy confers markedly enhanced stability on the radical cation. 1•+ is stable across an exceptionally wide redox range (> 1 V), permitting its isolation in crystalline form. Further single-electron oxidation affords borenium dication 12+, thereby establishing an organoboron redox system fully characterized in all three redox states. We perceive that this strategy can be extended to other transient organic radicals to widen their redox stability window and facilitate their isolation. Organic molecules that can access various redox states have potential applications in electronics, batteries, catalysis, among others. Here the authors report the preparation of an unsymmetrical organoboron analogue of Thiele’s hydrocarbon and study its one- and two-electron oxidation reactions; remarkably, the radical cation is stable over a redox range of > 1 V and can also be isolated.
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12
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Lu W, Jayaraman A, Fantuzzi F, Dewhurst RD, Härterich M, Dietz M, Hagspiel S, Krummenacher I, Hammond K, Cui J, Braunschweig H. An Unsymmetrical, Cyclic Diborene Based on a Chelating CAAC Ligand and its Small-Molecule Activation and Rearrangement Chemistry. Angew Chem Int Ed Engl 2021; 61:e202113947. [PMID: 34750945 PMCID: PMC9299934 DOI: 10.1002/anie.202113947] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/14/2021] [Indexed: 01/15/2023]
Abstract
A one‐pot synthesis of a CAAC‐stabilized, unsymmetrical, cyclic diborene was achieved via consecutive two‐electron reduction steps from an adduct of CAAC and B2Br4(SMe2)2. Theoretical studies revealed that this diborene has a considerably smaller HOMO–LUMO gap than those of reported NHC‐ and phosphine‐supported diborenes. Complexation of the diborene with [AuCl(PCy3)] afforded two diborene–AuI π complexes, while reaction with DurBH2, P4 and a terminal acetylene led to the cleavage of B−H, P−P, and C−C π bonds, respectively. Thermal rearrangement of the diborene gave an electron‐rich cyclic alkylideneborane, which readily coordinated to AgI via its B=C double bond.
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Affiliation(s)
- Wei Lu
- Institute for Inorganic Chemistry, Julius-Maximilians-Universität Würzburg, Am Hubland, 97074, Würzburg, Germany.,Institute for Sustainable Chemistry & Catalysis with Boron, Julius-Maximilians-Universität Würzburg, Am Hubland, 97074, Würzburg, Germany.,Key Laboratory of Green Chemistry & Technology of Ministry of Education, College of Chemistry, Sichuan University, 29 Wangjiang Road, Chengdu, 610064, P. R. China
| | - Arumugam Jayaraman
- Institute for Inorganic Chemistry, Julius-Maximilians-Universität Würzburg, Am Hubland, 97074, Würzburg, Germany.,Institute for Sustainable Chemistry & Catalysis with Boron, Julius-Maximilians-Universität Würzburg, Am Hubland, 97074, Würzburg, Germany
| | - Felipe Fantuzzi
- Institute for Inorganic Chemistry, Julius-Maximilians-Universität Würzburg, Am Hubland, 97074, Würzburg, Germany.,Institute for Sustainable Chemistry & Catalysis with Boron, Julius-Maximilians-Universität Würzburg, Am Hubland, 97074, Würzburg, Germany.,School of Physical Sciences, Ingram Building, University of Kent, Park Wood Road, Canterbury, CT2 7NH, United Kingdom
| | - Rian D Dewhurst
- Institute for Inorganic Chemistry, Julius-Maximilians-Universität Würzburg, Am Hubland, 97074, Würzburg, Germany.,Institute for Sustainable Chemistry & Catalysis with Boron, Julius-Maximilians-Universität Würzburg, Am Hubland, 97074, Würzburg, Germany
| | - Marcel Härterich
- Institute for Inorganic Chemistry, Julius-Maximilians-Universität Würzburg, Am Hubland, 97074, Würzburg, Germany.,Institute for Sustainable Chemistry & Catalysis with Boron, Julius-Maximilians-Universität Würzburg, Am Hubland, 97074, Würzburg, Germany
| | - Maximilian Dietz
- Institute for Inorganic Chemistry, Julius-Maximilians-Universität Würzburg, Am Hubland, 97074, Würzburg, Germany.,Institute for Sustainable Chemistry & Catalysis with Boron, Julius-Maximilians-Universität Würzburg, Am Hubland, 97074, Würzburg, Germany
| | - Stephan Hagspiel
- Institute for Inorganic Chemistry, Julius-Maximilians-Universität Würzburg, Am Hubland, 97074, Würzburg, Germany.,Institute for Sustainable Chemistry & Catalysis with Boron, Julius-Maximilians-Universität Würzburg, Am Hubland, 97074, Würzburg, Germany
| | - Ivo Krummenacher
- Institute for Inorganic Chemistry, Julius-Maximilians-Universität Würzburg, Am Hubland, 97074, Würzburg, Germany.,Institute for Sustainable Chemistry & Catalysis with Boron, Julius-Maximilians-Universität Würzburg, Am Hubland, 97074, Würzburg, Germany
| | - Kai Hammond
- Institute for Inorganic Chemistry, Julius-Maximilians-Universität Würzburg, Am Hubland, 97074, Würzburg, Germany.,Institute for Sustainable Chemistry & Catalysis with Boron, Julius-Maximilians-Universität Würzburg, Am Hubland, 97074, Würzburg, Germany
| | - Jingjing Cui
- Institute for Inorganic Chemistry, Julius-Maximilians-Universität Würzburg, Am Hubland, 97074, Würzburg, Germany.,Institute for Sustainable Chemistry & Catalysis with Boron, Julius-Maximilians-Universität Würzburg, Am Hubland, 97074, Würzburg, Germany
| | - Holger Braunschweig
- Institute for Inorganic Chemistry, Julius-Maximilians-Universität Würzburg, Am Hubland, 97074, Würzburg, Germany.,Institute for Sustainable Chemistry & Catalysis with Boron, Julius-Maximilians-Universität Würzburg, Am Hubland, 97074, Würzburg, Germany
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13
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Abstract
The amidinatoamidosilylene [LSiNMe2] [1; L = PhC(NtBu)2] was reacted with B2Br4(SMe2)2 in toluene at room temperature to form the bis(silylene)tetrabromodiborane [L{Me2N}Si]2B2Br4 (2). It was then reacted with excess KC8 in tetrahydrofuran at room temperature to afford the bis(silylene)dibromodiborene [L{Me2N}Si]2B2Br2 (3).
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Affiliation(s)
- Jun Fan
- Division of Chemistry and Biological Chemistry, School of Physical and Mathematical Sciences, Nanyang Technological University, Singapore 637371, Singapore
| | - Ming-Chung Yang
- Department of Applied Chemistry, National Chiayi University, Chiayi 60004, Taiwan
| | - Ming-Der Su
- Department of Applied Chemistry, National Chiayi University, Chiayi 60004, Taiwan.,Department of Medicinal and Applied Chemistry, Kaohsiung Medical University, Kaohsiung 80708, Taiwan
| | - Cheuk-Wai So
- Division of Chemistry and Biological Chemistry, School of Physical and Mathematical Sciences, Nanyang Technological University, Singapore 637371, Singapore
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14
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Arrowsmith M, Endres S, Heinz M, Nestler V, Holthausen MC, Braunschweig H. Probing the Boundaries between Lewis-Basic and Redox Behavior of a Parent Borylene. Chemistry 2021; 27:17660-17668. [PMID: 34596278 PMCID: PMC9299150 DOI: 10.1002/chem.202103256] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/08/2021] [Indexed: 11/09/2022]
Abstract
The parent borylene (CAAC)(Me3P)BH, 1 (CAAC=cyclic alkyl(amino)carbene), acts both as a Lewis base and one‐electron reducing agent towards group 13 trichlorides (ECl3, E=B, Al, Ga, In), yielding the adducts 1‐ECl3 and increasing proportions of the radical cation [1]•+ for the heavier group 13 analogues. With boron trihalides (BX3, X=F, Cl, Br, I) 1 undergoes sequential adduct formation and halide abstraction reactions to yield borylboronium cations and shows an increasing tendency towards redox processes for the heavier halides. Calculations confirm that 1 acts as a strong Lewis base towards EX3 and show a marked increase in the B−E bond dissociation energies down both group 13 and the halide group.
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Affiliation(s)
- Merle Arrowsmith
- Institute for Inorganic Chemistry, Julius-Maximilians-Universität Würzburg, Am Hubland, 97074, Würzburg, Germany.,Institute for Sustainable Chemistry & Catalysis with Boron, Julius-Maximilians-Universität Würzburg, Am Hubland, 97074, Würzburg, Germany
| | - Sara Endres
- Institute for Inorganic Chemistry, Julius-Maximilians-Universität Würzburg, Am Hubland, 97074, Würzburg, Germany.,Institute for Sustainable Chemistry & Catalysis with Boron, Julius-Maximilians-Universität Würzburg, Am Hubland, 97074, Würzburg, Germany
| | - Myron Heinz
- Institut für Anorganische und Analytische Chemie, Goethe-Universität Frankfurt am Main, Max-von-Laue-Str. 7, 60438, Frankfurt am Main, Germany
| | - Vincent Nestler
- Institute for Inorganic Chemistry, Julius-Maximilians-Universität Würzburg, Am Hubland, 97074, Würzburg, Germany.,Institute for Sustainable Chemistry & Catalysis with Boron, Julius-Maximilians-Universität Würzburg, Am Hubland, 97074, Würzburg, Germany
| | - Max C Holthausen
- Institut für Anorganische und Analytische Chemie, Goethe-Universität Frankfurt am Main, Max-von-Laue-Str. 7, 60438, Frankfurt am Main, Germany
| | - Holger Braunschweig
- Institute for Inorganic Chemistry, Julius-Maximilians-Universität Würzburg, Am Hubland, 97074, Würzburg, Germany.,Institute for Sustainable Chemistry & Catalysis with Boron, Julius-Maximilians-Universität Würzburg, Am Hubland, 97074, Würzburg, Germany
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15
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Bellotti P, Koy M, Hopkinson MN, Glorius F. Recent advances in the chemistry and applications of N-heterocyclic carbenes. Nat Rev Chem 2021; 5:711-725. [PMID: 37118184 DOI: 10.1038/s41570-021-00321-1] [Citation(s) in RCA: 209] [Impact Index Per Article: 69.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 07/22/2021] [Indexed: 12/18/2022]
Abstract
N-Heterocyclic carbenes, despite being isolated and characterized three decades ago, still capture scientists' interest as versatile, modular and strongly coordinating moieties. In the last decade, driven by the increasingly refined fundamental understanding of their behaviour, the emergence of new carbene frameworks and cogent sustainability issues, N-heterocyclic carbenes have experienced a tremendous increase in utilization across several disparate fields. In this Review, a concise overview of N-heterocyclic carbenes encompassing their history, properties and applications in transition metal catalysis, on-surface chemistry, main group chemistry and organocatalysis is provided. Emphasis is placed on developments emerging in the last seven years and on envisaging future directions.
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16
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Stoy A, Arrowsmith M, Eyßelein M, Dellermann T, Mies J, Radacki K, Kupfer T, Braunschweig H. NHC-Stabilized 1,2-Dihalodiborenes: Synthesis, Characterization, and Reactivity Toward Elemental Chalcogens. Inorg Chem 2021; 60:12625-12633. [PMID: 34042444 DOI: 10.1021/acs.inorgchem.1c01169] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/04/2023]
Abstract
The 2-fold reduction of B2X4(NHC)2 (X = Cl, Br, I; NHC = (un)saturated N-heterocyclic carbene) yields the corresponding green-colored 1,2-dihalodiborenes B2X2(NHC)2, the 11B NMR resonances of which are strongly upfield-shifted upon descending the halide group. The diborenes crystallize as the trans isomers, with relatively short B═B double bonds (1.513(9) to 1.568(4) Å). Cyclic voltammetric experiments with these diborenes reveal reversible one-electron oxidation processes to the corresponding diboron radical cation (E1/2 = -1.16 to -1.50 V); the reducing power of B2X2(NHC)2 increasing with the electronegativity of the halide and for the less π-accepting unsaturated NHCs. The main UV-vis absorption (393-463 nm), which corresponds mainly to a highest occupied molecular orbital (HOMO) → lowest unoccupied molecular orbital (LUMO) transition, undergoes a blueshift upon descending the halide group and shows some dependence on the stereoelectronics of the NHC ligands. Computational analyses show that the HOMO of B2X2(NHC)2 is mostly localized on the B═B π bond, with the contribution from halide p orbitals decreasing down the group, and the saturated NHCs affording some π-bonding delocalization over the B-CNHC bonds. The calculated HOMO and LUMO energies decrease upon descending the halide group, while the HOMO-LUMO gap also decreases, correlating well with the cyclovoltammetry and UV-vis data. The reactions of B2Br2(NHC)2 with elemental sulfur and red selenium lead to the formation of the corresponding diborathiiranes and seleniranes, respectively, which were characterized by NMR and UV-vis spectroscopy, cyclic voltammetry, and X-ray diffraction analyses. In one case, an additional one-electron oxidation yields a unique cyclic B2Se radical cation. Computational analyses show that the localization of the HOMO and HOMO - 1 of the diboraseleniranes is inverted compared to the diborathiiranes.
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Affiliation(s)
- Andreas Stoy
- Institute for Inorganic Chemistry, Julius-Maximilians-Universität Würzburg, Am Hubland, 97074 Würzburg, Germany.,Institute for Sustainable Chemistry & Catalysis with Boron, Julius-Maximilians-Universität Würzburg, Am Hubland, 97074 Würzburg, Germany
| | - Merle Arrowsmith
- Institute for Inorganic Chemistry, Julius-Maximilians-Universität Würzburg, Am Hubland, 97074 Würzburg, Germany.,Institute for Sustainable Chemistry & Catalysis with Boron, Julius-Maximilians-Universität Würzburg, Am Hubland, 97074 Würzburg, Germany
| | - Maximilian Eyßelein
- Institute for Inorganic Chemistry, Julius-Maximilians-Universität Würzburg, Am Hubland, 97074 Würzburg, Germany.,Institute for Sustainable Chemistry & Catalysis with Boron, Julius-Maximilians-Universität Würzburg, Am Hubland, 97074 Würzburg, Germany
| | - Theresa Dellermann
- Institute for Inorganic Chemistry, Julius-Maximilians-Universität Würzburg, Am Hubland, 97074 Würzburg, Germany.,Institute for Sustainable Chemistry & Catalysis with Boron, Julius-Maximilians-Universität Würzburg, Am Hubland, 97074 Würzburg, Germany
| | - Jan Mies
- Institute for Inorganic Chemistry, Julius-Maximilians-Universität Würzburg, Am Hubland, 97074 Würzburg, Germany.,Institute for Sustainable Chemistry & Catalysis with Boron, Julius-Maximilians-Universität Würzburg, Am Hubland, 97074 Würzburg, Germany
| | - Krzysztof Radacki
- Institute for Inorganic Chemistry, Julius-Maximilians-Universität Würzburg, Am Hubland, 97074 Würzburg, Germany.,Institute for Sustainable Chemistry & Catalysis with Boron, Julius-Maximilians-Universität Würzburg, Am Hubland, 97074 Würzburg, Germany
| | - Thomas Kupfer
- Institute for Inorganic Chemistry, Julius-Maximilians-Universität Würzburg, Am Hubland, 97074 Würzburg, Germany.,Institute for Sustainable Chemistry & Catalysis with Boron, Julius-Maximilians-Universität Würzburg, Am Hubland, 97074 Würzburg, Germany
| | - Holger Braunschweig
- Institute for Inorganic Chemistry, Julius-Maximilians-Universität Würzburg, Am Hubland, 97074 Würzburg, Germany.,Institute for Sustainable Chemistry & Catalysis with Boron, Julius-Maximilians-Universität Würzburg, Am Hubland, 97074 Würzburg, Germany
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17
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Fan J, Mah JQ, Yang MC, Su MD, So CW. A N-Phosphinoamidinato NHC-Diborene Catalyst for Hydroboration. J Am Chem Soc 2021; 143:4993-5002. [PMID: 33448848 DOI: 10.1021/jacs.0c12627] [Citation(s) in RCA: 16] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022]
Abstract
The use of the N-phosphinoamidinato NHC-diborene catalyst 2 for hydroboration is described. The N-phosphinoamidine tBu2PN(H)C(Ph)═N(2,6-iPr2C6H3) was reacted with nBuLi in Et2O to afford the lithium derivative, which was then treated with B2Br4(SMe2)2 in toluene to form the N-phosphinoamidinate-bridged diborane 1. It was reacted with the N-heterocyclic carbene IMe (:C{N(CH3)C(CH3)}2) and excess potassium graphite at room temperature in toluene to give the N-phosphinoamidinato NHC-diborene compound 2. It can stoichiometrically activate ammonia-borane and carbon dioxide. It also showed catalytic capability. A 2 mol % portion of 2 catalyzed the hydroboration of carbon dioxide (CO2) with pinacolborane (HBpin) in deuterated benzene (C6D6) at 110 °C (conversion >99%), which afforded the methoxyborane [pinBOMe] (yield 97.8%, TOF 33.3 h-1) and the bis(boryl) oxide [(pinB)2O]. In addition, 5 mol % of 2 catalyzed the N-formylation of secondary and primary amines by carbon dioxide and pinacolborane to yield the N-formamides (average yield 91.6%, TOF 25.9 h-1). Moreover, 2 showed chemoselectivity toward catalytic hydroboration of carbonyl compounds. In mechanistic studies, the B═B double bond in compound 2 activated the substrates, the intermediates of which then underwent hydroboration with pinacolborane to yield the products and regenerate catalyst 2.
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Affiliation(s)
- Jun Fan
- Division of Chemistry and Biological Chemistry, School of Physical and Mathematical Sciences, Nanyang Technological University, Singapore 637371
| | - Jian-Qiang Mah
- Division of Chemistry and Biological Chemistry, School of Physical and Mathematical Sciences, Nanyang Technological University, Singapore 637371
| | - Ming-Chung Yang
- Department of Applied Chemistry, National Chiayi University, Chiayi 60004, Taiwan
| | - Ming-Der Su
- Department of Applied Chemistry, National Chiayi University, Chiayi 60004, Taiwan.,Department of Medicinal and Applied Chemistry, Kaohsiung Medical University, Kaohsiung 80708, Taiwan
| | - Cheuk-Wai So
- Division of Chemistry and Biological Chemistry, School of Physical and Mathematical Sciences, Nanyang Technological University, Singapore 637371
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18
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Borthakur B, Ghosh B, Phukan AK. The flourishing chemistry of carbene stabilized compounds of group 13 and 14 elements. Polyhedron 2021. [DOI: 10.1016/j.poly.2021.115049] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
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19
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Borthakur R, Chandrasekhar V. Boron-heteroelement (B–E; E = Al, C, Si, Ge, N, P, As, Bi, O, S, Se, Te) multiply bonded compounds: Recent advances. Coord Chem Rev 2021. [DOI: 10.1016/j.ccr.2020.213647] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
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20
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He J, Rauch F, Krummenacher I, Braunschweig H, Finze M, Marder TB. Two derivatives of phenylpyridyl-fused boroles with contrasting electronic properties: decreasing and enhancing the electron accepting ability. Dalton Trans 2021; 50:355-361. [PMID: 33320139 DOI: 10.1039/d0dt03619f] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/18/2023]
Abstract
Two derivatives of phenylpyridyl-fused boroles were prepared via functionalization of the pyridyl groups, namely to an electron-rich dihydropyridine moiety (compound 1) and an electron-deficient N-methylpyridinium cation (compound 2). Due to strong conjugation between the dihydropyridine moiety and the boron atom, the reduction potential of compound 1 shifts cathodically. In contrast, compound 2 exhibits three reduction processes with a first reversible reduction potential anodically shifted in comparison to its precursor (TipPBB2) or the non-borylated framework 1-methyl-2-phenylpyridin-1-ium triflate (3). The significantly anodically shifted reduction potential indicates the extreme electron deficiency of compound 2, which also leads to the reversible coordination of THF. Photophysical properties of both compounds in different solvents were investigated. Theoretical studies further support the strong conjugation in the ground state of compound 1 and the electron-deficient property of compound 2.
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Affiliation(s)
- Jiang He
- Institute for Inorganic Chemistry and Institute for Sustainable Chemistry & Catalysis with Boron (ICB), Julius-Maximilians-Universität Würzburg, Am Hubland, 97074 Würzburg, Germany.
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21
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Kundu G, Pahar S, Tothadi S, Sen SS. Stepwise Nucleophilic Substitution to Access Saturated N-heterocyclic Carbene Haloboranes with Boron–Methyl Bonds. Organometallics 2020. [DOI: 10.1021/acs.organomet.0c00691] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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
| | - Sanjukta Pahar
- 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
| | - Srinu Tothadi
- Organic Chemistry Division, CSIR-National Chemical Laboratory, Dr. Homi Bhabha Road, Pashan, Pune 411008, 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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22
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Chen C, Hu ZB, Ruan H, Zhao Y, Zhang YQ, Tan G, Song Y, Wang X. Tuning the Single-Molecule Magnetism of Dysprosium Complexes by a Redox-Noninnocent Diborane Ligand. Organometallics 2020. [DOI: 10.1021/acs.organomet.9b00819] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Chao Chen
- State Key Laboratory of Coordination Chemistry, Jiangsu Key Laboratory of Advanced Organic Materials, School of Chemistry and Chemical Engineering, Collaborative Innovation Center of Advanced Microstructures, Nanjing University, Nanjing 210023, China
| | - Zhao-Bo Hu
- State Key Laboratory of Coordination Chemistry, Jiangsu Key Laboratory of Advanced Organic Materials, School of Chemistry and Chemical Engineering, Collaborative Innovation Center of Advanced Microstructures, Nanjing University, Nanjing 210023, China
| | - Huapeng Ruan
- State Key Laboratory of Coordination Chemistry, Jiangsu Key Laboratory of Advanced Organic Materials, School of Chemistry and Chemical Engineering, Collaborative Innovation Center of Advanced Microstructures, Nanjing University, Nanjing 210023, China
| | - Yue Zhao
- State Key Laboratory of Coordination Chemistry, Jiangsu Key Laboratory of Advanced Organic Materials, School of Chemistry and Chemical Engineering, Collaborative Innovation Center of Advanced Microstructures, Nanjing University, Nanjing 210023, China
| | - Yi-Quan Zhang
- Jiangsu Key Laboratory for NSLSCS, School of Physical Science and Technology, Nanjing Normal University, Nanjing 210023, China
| | - Gengwen Tan
- State Key Laboratory of Coordination Chemistry, Jiangsu Key Laboratory of Advanced Organic Materials, School of Chemistry and Chemical Engineering, Collaborative Innovation Center of Advanced Microstructures, Nanjing University, Nanjing 210023, China
- College of Chemistry, Chemical Engineering and Materials Science, Soochow University, Suzhou 215123, China
| | - You Song
- State Key Laboratory of Coordination Chemistry, Jiangsu Key Laboratory of Advanced Organic Materials, School of Chemistry and Chemical Engineering, Collaborative Innovation Center of Advanced Microstructures, Nanjing University, Nanjing 210023, China
| | - Xinping Wang
- State Key Laboratory of Coordination Chemistry, Jiangsu Key Laboratory of Advanced Organic Materials, School of Chemistry and Chemical Engineering, Collaborative Innovation Center of Advanced Microstructures, Nanjing University, Nanjing 210023, China
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23
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Wang XQ, Wang W, Peng M, Zhang XZ. Free radicals for cancer theranostics. Biomaterials 2020; 266:120474. [PMID: 33125969 DOI: 10.1016/j.biomaterials.2020.120474] [Citation(s) in RCA: 65] [Impact Index Per Article: 16.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/20/2020] [Revised: 09/20/2020] [Accepted: 10/18/2020] [Indexed: 01/06/2023]
Abstract
Free radicals were generally regarded as highly reactive, transient and harmful species. In fact, some of the free radicals can also be inactive, long-lived and beneficial for our health. These properties of free radicals provide future possibilities for their application in various fields. Owning to their open-shell electronic structure, free radicals exhibit unique advantages in biomedical applications, such as high reactivity, photoacoustic and photothermal conversion ability, molecular magnetic. In this review, recent progress on free radicals and their applications in cancer theranostics are presented. Typical materials that exhibit controlled generation of free radicals and their applications for photodynamic therapy (PDT), chemodynamic therapy (CDT), sonodynamic therapy (SDT), gas therapy, hypoxic cancer treatment, photothermal therapy (PTT), photoacoustic imaging (PAI) and magnetic resonance imaging (MRI) are summarized and discussed.
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Affiliation(s)
- Xiao-Qiang Wang
- Key Laboratory of Biomedical Polymers of Ministry of Education & Department of Chemistry, Wuhan University, Wuhan, 430072, PR China; The State Key Laboratory of Refractories and Metallurgy, School of Chemistry and Chemical Engineering, Wuhan University of Science and Technology, Wuhan, 430081, PR China
| | - Wenjing Wang
- The State Key Laboratory of Refractories and Metallurgy, School of Chemistry and Chemical Engineering, Wuhan University of Science and Technology, Wuhan, 430081, PR China
| | - Mengyun Peng
- Key Laboratory of Biomedical Polymers of Ministry of Education & Department of Chemistry, Wuhan University, Wuhan, 430072, PR China; School of Pharmacy, Zhejiang Chinese Medical University, Hangzhou, 310000, PR China
| | - Xian-Zheng Zhang
- Key Laboratory of Biomedical Polymers of Ministry of Education & Department of Chemistry, Wuhan University, Wuhan, 430072, PR China.
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24
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Saalfrank C, Fantuzzi F, Kupfer T, Ritschel B, Hammond K, Krummenacher I, Bertermann R, Wirthensohn R, Finze M, Schmid P, Engel V, Engels B, Braunschweig H. cAAC-Stabilized 9,10-diboraanthracenes-Acenes with Open-Shell Singlet Biradical Ground States. Angew Chem Int Ed Engl 2020; 59:19338-19343. [PMID: 32662218 PMCID: PMC7589216 DOI: 10.1002/anie.202008206] [Citation(s) in RCA: 47] [Impact Index Per Article: 11.8] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/09/2020] [Indexed: 12/19/2022]
Abstract
Narrow HOMO-LUMO gaps and high charge-carrier mobilities make larger acenes potentially high-efficient materials for organic electronic applications. The performance of such molecules was shown to significantly increase with increasing number of fused benzene rings. Bulk quantities, however, can only be obtained reliably for acenes up to heptacene. Theoretically, (oligo)acenes and (poly)acenes are predicted to have open-shell singlet biradical and polyradical ground states, respectively, for which experimental evidence is still scarce. We have now been able to dramatically lower the HOMO-LUMO gap of acenes without the necessity of unfavorable elongation of their conjugated π system, by incorporating two boron atoms into the anthracene skeleton. Stabilizing the boron centers with cyclic (alkyl)(amino)carbenes gives neutral 9,10-diboraanthracenes, which are shown to feature disjointed, open-shell singlet biradical ground states.
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Affiliation(s)
- Christian Saalfrank
- Institut für Anorganische ChemieJulius-Maximilians-Universität WürzburgAm Hubland97074WürzburgGermany
- Institute for Sustainable Chemistry & Catalysis with BoronJulius-Maximilians-Universität WürzburgAm Hubland97074WürzburgGermany
| | - Felipe Fantuzzi
- Institut für Anorganische ChemieJulius-Maximilians-Universität WürzburgAm Hubland97074WürzburgGermany
- Institute for Sustainable Chemistry & Catalysis with BoronJulius-Maximilians-Universität WürzburgAm Hubland97074WürzburgGermany
- Institut für Physikalische und Theoretische ChemieJulius-Maximilians-Universität WürzburgEmil-Fischer-Strasse 4297074WürzburgGermany
| | - Thomas Kupfer
- Institut für Anorganische ChemieJulius-Maximilians-Universität WürzburgAm Hubland97074WürzburgGermany
- Institute for Sustainable Chemistry & Catalysis with BoronJulius-Maximilians-Universität WürzburgAm Hubland97074WürzburgGermany
| | - Benedikt Ritschel
- Institut für Anorganische ChemieJulius-Maximilians-Universität WürzburgAm Hubland97074WürzburgGermany
- Institute for Sustainable Chemistry & Catalysis with BoronJulius-Maximilians-Universität WürzburgAm Hubland97074WürzburgGermany
| | - Kai Hammond
- Institut für Anorganische ChemieJulius-Maximilians-Universität WürzburgAm Hubland97074WürzburgGermany
- Institute for Sustainable Chemistry & Catalysis with BoronJulius-Maximilians-Universität WürzburgAm Hubland97074WürzburgGermany
| | - Ivo Krummenacher
- Institut für Anorganische ChemieJulius-Maximilians-Universität WürzburgAm Hubland97074WürzburgGermany
- Institute for Sustainable Chemistry & Catalysis with BoronJulius-Maximilians-Universität WürzburgAm Hubland97074WürzburgGermany
| | - Rüdiger Bertermann
- Institut für Anorganische ChemieJulius-Maximilians-Universität WürzburgAm Hubland97074WürzburgGermany
- Institute for Sustainable Chemistry & Catalysis with BoronJulius-Maximilians-Universität WürzburgAm Hubland97074WürzburgGermany
| | - Raphael Wirthensohn
- Institut für Anorganische ChemieJulius-Maximilians-Universität WürzburgAm Hubland97074WürzburgGermany
- Institute for Sustainable Chemistry & Catalysis with BoronJulius-Maximilians-Universität WürzburgAm Hubland97074WürzburgGermany
| | - Maik Finze
- Institut für Anorganische ChemieJulius-Maximilians-Universität WürzburgAm Hubland97074WürzburgGermany
- Institute for Sustainable Chemistry & Catalysis with BoronJulius-Maximilians-Universität WürzburgAm Hubland97074WürzburgGermany
| | - Paul Schmid
- Institut für Physikalische und Theoretische ChemieJulius-Maximilians-Universität WürzburgEmil-Fischer-Strasse 4297074WürzburgGermany
| | - Volker Engel
- Institut für Physikalische und Theoretische ChemieJulius-Maximilians-Universität WürzburgEmil-Fischer-Strasse 4297074WürzburgGermany
| | - Bernd Engels
- Institut für Physikalische und Theoretische ChemieJulius-Maximilians-Universität WürzburgEmil-Fischer-Strasse 4297074WürzburgGermany
| | - Holger Braunschweig
- Institut für Anorganische ChemieJulius-Maximilians-Universität WürzburgAm Hubland97074WürzburgGermany
- Institute for Sustainable Chemistry & Catalysis with BoronJulius-Maximilians-Universität WürzburgAm Hubland97074WürzburgGermany
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25
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Rauch F, Fuchs S, Friedrich A, Sieh D, Krummenacher I, Braunschweig H, Finze M, Marder TB. Highly Stable, Readily Reducible, Fluorescent, Trifluoromethylated 9-Borafluorenes. Chemistry 2020; 26:12794-12808. [PMID: 31999019 PMCID: PMC7589458 DOI: 10.1002/chem.201905559] [Citation(s) in RCA: 30] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/09/2019] [Indexed: 01/29/2023]
Abstract
Three different perfluoroalkylated borafluorenes (F Bf) were prepared and their electronic and photophysical properties were investigated. The systems have four trifluoromethyl moieties on the borafluorene moiety as well as two trifluoromethyl groups at the ortho positions of their exo-aryl moieties. They differ with regard to the para substituents on their exo-aryl moieties, being a proton (F XylF Bf, F Xyl: 2,6-bis(trifluoromethyl)phenyl), a trifluoromethyl group (F MesF Bf, F Mes: 2,4,6-tris(trifluoromethyl)phenyl) or a dimethylamino group (p-NMe2 -F XylF Bf, p-NMe2 -F Xyl: 4-(dimethylamino)-2,6-bis(trifluoromethyl)phenyl), respectively. All derivatives exhibit extraordinarily low reduction potentials, comparable to those of perylenediimides. The most electron-deficient derivative F MesF Bf was also chemically reduced and its radical anion isolated and characterized. Furthermore, all compounds exhibit very long fluorescent lifetimes of about 250 ns up to 1.6 μs; however, the underlying mechanisms responsible for this differ. The donor-substituted derivative p-NMe2 -F XylF Bf exhibits thermally activated delayed fluorescence (TADF) from a charge-transfer (CT) state, whereas the F MesF Bf and F XylF Bf borafluorenes exhibit only weakly allowed locally excited (LE) transitions due to their symmetry and low transition-dipole moments.
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Affiliation(s)
- Florian Rauch
- Institute for Inorganic Chemistry and Institute for Sustainable Chemistry & Catalysis with Boron (ICB)Julius-Maximilians-Universität WürzburgAm Hubland97074WürzburgGermany
| | - Sonja Fuchs
- Institute for Inorganic Chemistry and Institute for Sustainable Chemistry & Catalysis with Boron (ICB)Julius-Maximilians-Universität WürzburgAm Hubland97074WürzburgGermany
| | - Alexandra Friedrich
- Institute for Inorganic Chemistry and Institute for Sustainable Chemistry & Catalysis with Boron (ICB)Julius-Maximilians-Universität WürzburgAm Hubland97074WürzburgGermany
| | - Daniel Sieh
- Institute for Inorganic Chemistry and Institute for Sustainable Chemistry & Catalysis with Boron (ICB)Julius-Maximilians-Universität WürzburgAm Hubland97074WürzburgGermany
| | - Ivo Krummenacher
- Institute for Inorganic Chemistry and Institute for Sustainable Chemistry & Catalysis with Boron (ICB)Julius-Maximilians-Universität WürzburgAm Hubland97074WürzburgGermany
| | - Holger Braunschweig
- Institute for Inorganic Chemistry and Institute for Sustainable Chemistry & Catalysis with Boron (ICB)Julius-Maximilians-Universität WürzburgAm Hubland97074WürzburgGermany
| | - Maik Finze
- Institute for Inorganic Chemistry and Institute for Sustainable Chemistry & Catalysis with Boron (ICB)Julius-Maximilians-Universität WürzburgAm Hubland97074WürzburgGermany
| | - Todd B. Marder
- Institute for Inorganic Chemistry and Institute for Sustainable Chemistry & Catalysis with Boron (ICB)Julius-Maximilians-Universität WürzburgAm Hubland97074WürzburgGermany
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26
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Hermann A, Fantuzzi F, Arrowsmith M, Zorn T, Krummenacher I, Ritschel B, Radacki K, Engels B, Braunschweig H. Oxidation, Coordination, and Nickel‐Mediated Deconstruction of a Highly Electron‐Rich Diboron Analogue of 1,3,5‐Hexatriene. Angew Chem Int Ed Engl 2020. [DOI: 10.1002/ange.202006131] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/06/2023]
Affiliation(s)
- Alexander Hermann
- Institute for Inorganic Chemistry & the Institute for Sustainable, Chemistry & Catalysis with Boron Julius-Maximilians-University Würzburg Am Hubland 97074 Würzburg Germany
| | - Felipe Fantuzzi
- Institute for Inorganic Chemistry & the Institute for Sustainable, Chemistry & Catalysis with Boron Julius-Maximilians-University Würzburg Am Hubland 97074 Würzburg Germany
- Institute for Physical and Theoretical Chemistry Julius-Maximilians-University Würzburg Emil-Fischer-Straße 42 97074 Würzburg Germany
| | - Merle Arrowsmith
- Institute for Inorganic Chemistry & the Institute for Sustainable, Chemistry & Catalysis with Boron Julius-Maximilians-University Würzburg Am Hubland 97074 Würzburg Germany
| | - Theresa Zorn
- Institute for Inorganic Chemistry & the Institute for Sustainable, Chemistry & Catalysis with Boron Julius-Maximilians-University Würzburg Am Hubland 97074 Würzburg Germany
| | - Ivo Krummenacher
- Institute for Inorganic Chemistry & the Institute for Sustainable, Chemistry & Catalysis with Boron Julius-Maximilians-University Würzburg Am Hubland 97074 Würzburg Germany
| | - Benedikt Ritschel
- Institute for Inorganic Chemistry & the Institute for Sustainable, Chemistry & Catalysis with Boron Julius-Maximilians-University Würzburg Am Hubland 97074 Würzburg Germany
| | - Krzysztof Radacki
- Institute for Inorganic Chemistry & the Institute for Sustainable, Chemistry & Catalysis with Boron Julius-Maximilians-University Würzburg Am Hubland 97074 Würzburg Germany
| | - Bernd Engels
- Institute for Physical and Theoretical Chemistry Julius-Maximilians-University Würzburg Emil-Fischer-Straße 42 97074 Würzburg Germany
| | - Holger Braunschweig
- Institute for Inorganic Chemistry & the Institute for Sustainable, Chemistry & Catalysis with Boron Julius-Maximilians-University Würzburg Am Hubland 97074 Würzburg Germany
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27
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Hermann A, Fantuzzi F, Arrowsmith M, Zorn T, Krummenacher I, Ritschel B, Radacki K, Engels B, Braunschweig H. Oxidation, Coordination, and Nickel-Mediated Deconstruction of a Highly Electron-Rich Diboron Analogue of 1,3,5-Hexatriene. Angew Chem Int Ed Engl 2020; 59:15717-15725. [PMID: 32449598 PMCID: PMC7497145 DOI: 10.1002/anie.202006131] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/28/2020] [Indexed: 01/02/2023]
Abstract
The reductive coupling of an N-heterocyclic carbene (NHC) stabilized (dibromo)vinylborane yields a 1,2-divinyldiborene, which, although isoelectronic to a 1,3,5-triene, displays no extended π conjugation because of twisting of the C2 B2 C2 chain. While this divinyldiborene coordinates to copper(I) and platinum(0) in an η2 -B2 and η4 -C2 B2 fashion, respectively, it undergoes a complex rearrangement to an η4 -1,3-diborete upon complexation with nickel(0).
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Affiliation(s)
- Alexander Hermann
- Institute for Inorganic Chemistry & the Institute for Sustainable, Chemistry & Catalysis with BoronJulius-Maximilians-University WürzburgAm Hubland97074WürzburgGermany
| | - Felipe Fantuzzi
- Institute for Inorganic Chemistry & the Institute for Sustainable, Chemistry & Catalysis with BoronJulius-Maximilians-University WürzburgAm Hubland97074WürzburgGermany
- Institute for Physical and Theoretical ChemistryJulius-Maximilians-University WürzburgEmil-Fischer-Straße 4297074WürzburgGermany
| | - Merle Arrowsmith
- Institute for Inorganic Chemistry & the Institute for Sustainable, Chemistry & Catalysis with BoronJulius-Maximilians-University WürzburgAm Hubland97074WürzburgGermany
| | - Theresa Zorn
- Institute for Inorganic Chemistry & the Institute for Sustainable, Chemistry & Catalysis with BoronJulius-Maximilians-University WürzburgAm Hubland97074WürzburgGermany
| | - Ivo Krummenacher
- Institute for Inorganic Chemistry & the Institute for Sustainable, Chemistry & Catalysis with BoronJulius-Maximilians-University WürzburgAm Hubland97074WürzburgGermany
| | - Benedikt Ritschel
- Institute for Inorganic Chemistry & the Institute for Sustainable, Chemistry & Catalysis with BoronJulius-Maximilians-University WürzburgAm Hubland97074WürzburgGermany
| | - Krzysztof Radacki
- Institute for Inorganic Chemistry & the Institute for Sustainable, Chemistry & Catalysis with BoronJulius-Maximilians-University WürzburgAm Hubland97074WürzburgGermany
| | - Bernd Engels
- Institute for Physical and Theoretical ChemistryJulius-Maximilians-University WürzburgEmil-Fischer-Straße 4297074WürzburgGermany
| | - Holger Braunschweig
- Institute for Inorganic Chemistry & the Institute for Sustainable, Chemistry & Catalysis with BoronJulius-Maximilians-University WürzburgAm Hubland97074WürzburgGermany
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28
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Saalfrank C, Fantuzzi F, Kupfer T, Ritschel B, Hammond K, Krummenacher I, Bertermann R, Wirthensohn R, Finze M, Schmid P, Engel V, Engels B, Braunschweig H. cAAC‐stabilisierte 9,10‐Diboraanthracene – offenschalige Singulettbiradikale. Angew Chem Int Ed Engl 2020. [DOI: 10.1002/ange.202008206] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Affiliation(s)
- Christian Saalfrank
- Institut für Anorganische Chemie Julius-Maximilians-Universität Würzburg Am Hubland 97074 Würzburg Germany
- Institut für Nachhaltige Chemie & Katalyse mit Bor Julius-Maximilians-Universität Würzburg Am Hubland 97074 Würzburg Germany
| | - Felipe Fantuzzi
- Institut für Anorganische Chemie Julius-Maximilians-Universität Würzburg Am Hubland 97074 Würzburg Germany
- Institut für Nachhaltige Chemie & Katalyse mit Bor Julius-Maximilians-Universität Würzburg Am Hubland 97074 Würzburg Germany
- Institut für Physikalische und Theoretische Chemie Julius-Maximilians-Universität Würzburg Emil-Fischer-Straße 42 97074 Würzburg Germany
| | - Thomas Kupfer
- Institut für Anorganische Chemie Julius-Maximilians-Universität Würzburg Am Hubland 97074 Würzburg Germany
- Institut für Nachhaltige Chemie & Katalyse mit Bor Julius-Maximilians-Universität Würzburg Am Hubland 97074 Würzburg Germany
| | - Benedikt Ritschel
- Institut für Anorganische Chemie Julius-Maximilians-Universität Würzburg Am Hubland 97074 Würzburg Germany
- Institut für Nachhaltige Chemie & Katalyse mit Bor Julius-Maximilians-Universität Würzburg Am Hubland 97074 Würzburg Germany
| | - Kai Hammond
- Institut für Anorganische Chemie Julius-Maximilians-Universität Würzburg Am Hubland 97074 Würzburg Germany
- Institut für Nachhaltige Chemie & Katalyse mit Bor Julius-Maximilians-Universität Würzburg Am Hubland 97074 Würzburg Germany
| | - Ivo Krummenacher
- Institut für Anorganische Chemie Julius-Maximilians-Universität Würzburg Am Hubland 97074 Würzburg Germany
- Institut für Nachhaltige Chemie & Katalyse mit Bor Julius-Maximilians-Universität Würzburg Am Hubland 97074 Würzburg Germany
| | - Rüdiger Bertermann
- Institut für Anorganische Chemie Julius-Maximilians-Universität Würzburg Am Hubland 97074 Würzburg Germany
- Institut für Nachhaltige Chemie & Katalyse mit Bor Julius-Maximilians-Universität Würzburg Am Hubland 97074 Würzburg Germany
| | - Raphael Wirthensohn
- Institut für Anorganische Chemie Julius-Maximilians-Universität Würzburg Am Hubland 97074 Würzburg Germany
- Institut für Nachhaltige Chemie & Katalyse mit Bor Julius-Maximilians-Universität Würzburg Am Hubland 97074 Würzburg Germany
| | - Maik Finze
- Institut für Anorganische Chemie Julius-Maximilians-Universität Würzburg Am Hubland 97074 Würzburg Germany
- Institut für Nachhaltige Chemie & Katalyse mit Bor Julius-Maximilians-Universität Würzburg Am Hubland 97074 Würzburg Germany
| | - Paul Schmid
- Institut für Physikalische und Theoretische Chemie Julius-Maximilians-Universität Würzburg Emil-Fischer-Straße 42 97074 Würzburg Germany
| | - Volker Engel
- Institut für Physikalische und Theoretische Chemie Julius-Maximilians-Universität Würzburg Emil-Fischer-Straße 42 97074 Würzburg Germany
| | - Bernd Engels
- Institut für Physikalische und Theoretische Chemie Julius-Maximilians-Universität Würzburg Emil-Fischer-Straße 42 97074 Würzburg Germany
| | - Holger Braunschweig
- Institut für Anorganische Chemie Julius-Maximilians-Universität Würzburg Am Hubland 97074 Würzburg Germany
- Institut für Nachhaltige Chemie & Katalyse mit Bor Julius-Maximilians-Universität Würzburg Am Hubland 97074 Würzburg Germany
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29
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Liu S, Légaré MA, Seufert J, Prieschl D, Rempel A, Englert L, Dellermann T, Paprocki V, Stoy A, Braunschweig H. 2,2′-Bipyridyl as a Redox-Active Borylene Abstraction Agent. Inorg Chem 2020; 59:10866-10873. [DOI: 10.1021/acs.inorgchem.0c01383] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Siyuan Liu
- Institute for Inorganic Chemistry, Julius-Maximilians-Universität Würzburg, Am Hubland, 97074 Würzburg, Germany
- Institute for Sustainable Chemistry & Catalysis with Boron, Julius-Maximilians-Universität Würzburg, Am Hubland, 97074 Würzburg, Germany
| | - Marc-André Légaré
- Institute for Inorganic Chemistry, Julius-Maximilians-Universität Würzburg, Am Hubland, 97074 Würzburg, Germany
- Institute for Sustainable Chemistry & Catalysis with Boron, Julius-Maximilians-Universität Würzburg, Am Hubland, 97074 Würzburg, Germany
| | - Jens Seufert
- Institute for Inorganic Chemistry, Julius-Maximilians-Universität Würzburg, Am Hubland, 97074 Würzburg, Germany
- Institute for Sustainable Chemistry & Catalysis with Boron, Julius-Maximilians-Universität Würzburg, Am Hubland, 97074 Würzburg, Germany
| | - Dominic Prieschl
- Institute for Inorganic Chemistry, Julius-Maximilians-Universität Würzburg, Am Hubland, 97074 Würzburg, Germany
- Institute for Sustainable Chemistry & Catalysis with Boron, Julius-Maximilians-Universität Würzburg, Am Hubland, 97074 Würzburg, Germany
| | - Anna Rempel
- Institute for Inorganic Chemistry, Julius-Maximilians-Universität Würzburg, Am Hubland, 97074 Würzburg, Germany
- Institute for Sustainable Chemistry & Catalysis with Boron, Julius-Maximilians-Universität Würzburg, Am Hubland, 97074 Würzburg, Germany
| | - Lukas Englert
- Institute for Inorganic Chemistry, Julius-Maximilians-Universität Würzburg, Am Hubland, 97074 Würzburg, Germany
- Institute for Sustainable Chemistry & Catalysis with Boron, Julius-Maximilians-Universität Würzburg, Am Hubland, 97074 Würzburg, Germany
| | - Theresa Dellermann
- Institute for Inorganic Chemistry, Julius-Maximilians-Universität Würzburg, Am Hubland, 97074 Würzburg, Germany
- Institute for Sustainable Chemistry & Catalysis with Boron, Julius-Maximilians-Universität Würzburg, Am Hubland, 97074 Würzburg, Germany
| | - Valerie Paprocki
- Institute for Inorganic Chemistry, Julius-Maximilians-Universität Würzburg, Am Hubland, 97074 Würzburg, Germany
- Institute for Sustainable Chemistry & Catalysis with Boron, Julius-Maximilians-Universität Würzburg, Am Hubland, 97074 Würzburg, Germany
| | - Andreas Stoy
- Institute for Inorganic Chemistry, Julius-Maximilians-Universität Würzburg, Am Hubland, 97074 Würzburg, Germany
- Institute for Sustainable Chemistry & Catalysis with Boron, Julius-Maximilians-Universität Würzburg, Am Hubland, 97074 Würzburg, Germany
| | - Holger Braunschweig
- Institute for Inorganic Chemistry, Julius-Maximilians-Universität Würzburg, Am Hubland, 97074 Würzburg, Germany
- Institute for Sustainable Chemistry & Catalysis with Boron, Julius-Maximilians-Universität Würzburg, Am Hubland, 97074 Würzburg, Germany
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30
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Feng Z, Fang Y, Ruan H, Zhao Y, Tan G, Wang X. Stable Radical Cation and Dication of an N‐Heterocyclic Carbene Stabilized Digallene: Synthesis, Characterization and Reactivity. Angew Chem Int Ed Engl 2020. [DOI: 10.1002/ange.202000051] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Affiliation(s)
- Zhongtao Feng
- State Key Laboratory of Coordination ChemistryJiangsu Key Laboratory of Advanced Organic MaterialsSchool of Chemistry and Chemical EngineeringCollaborative Innovation Center of Advanced MicrostructuresNanjing University Nanjing 210023 P. R. China
| | - Yong Fang
- State Key Laboratory of Coordination ChemistryJiangsu Key Laboratory of Advanced Organic MaterialsSchool of Chemistry and Chemical EngineeringCollaborative Innovation Center of Advanced MicrostructuresNanjing University Nanjing 210023 P. R. China
| | - Huapeng Ruan
- State Key Laboratory of Coordination ChemistryJiangsu Key Laboratory of Advanced Organic MaterialsSchool of Chemistry and Chemical EngineeringCollaborative Innovation Center of Advanced MicrostructuresNanjing University Nanjing 210023 P. R. China
| | - Yue Zhao
- State Key Laboratory of Coordination ChemistryJiangsu Key Laboratory of Advanced Organic MaterialsSchool of Chemistry and Chemical EngineeringCollaborative Innovation Center of Advanced MicrostructuresNanjing University Nanjing 210023 P. R. China
| | - Gengwen Tan
- State Key Laboratory of Coordination ChemistryJiangsu Key Laboratory of Advanced Organic MaterialsSchool of Chemistry and Chemical EngineeringCollaborative Innovation Center of Advanced MicrostructuresNanjing University Nanjing 210023 P. R. China
- College of Chemistry, Chemical Engineering and Materials ScienceSoochow University Suzhou 215123 P. R. China
| | - Xinping Wang
- State Key Laboratory of Coordination ChemistryJiangsu Key Laboratory of Advanced Organic MaterialsSchool of Chemistry and Chemical EngineeringCollaborative Innovation Center of Advanced MicrostructuresNanjing University Nanjing 210023 P. R. China
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31
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Feng Z, Fang Y, Ruan H, Zhao Y, Tan G, Wang X. Stable Radical Cation and Dication of an N-Heterocyclic Carbene Stabilized Digallene: Synthesis, Characterization and Reactivity. Angew Chem Int Ed Engl 2020; 59:6769-6774. [PMID: 31994317 DOI: 10.1002/anie.202000051] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/02/2020] [Indexed: 11/06/2022]
Abstract
One- and two-electron oxidation of a digallene stabilized by an N-heterocyclic carbene afforded the first stable gallium-based radical cation and dication salts, respectively. Structural analysis and theoretical calculations reveal that the oxidation occurs at the Ga=Ga double bond, leading to removal of π electrons of the double bond and a decrease of the bond order. The spin density of the radical cation mainly locates at the two gallium centers as demonstrated by EPR spectroscopy and theoretical calculations. Moreover, the reactivity of the radical cation salt toward nBu3 SnH and cyclo-S8 was studied; a digallium-hydride cation salt containing a Ga-Ga single bond and a gallium sulfide cluster bearing an unprecedented ladder-like Ga4 S4 core structure were obtained, respectively.
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Affiliation(s)
- Zhongtao Feng
- State Key Laboratory of Coordination Chemistry, Jiangsu Key Laboratory of Advanced Organic Materials, School of Chemistry and Chemical Engineering, Collaborative Innovation Center of Advanced Microstructures, Nanjing University, Nanjing, 210023, P. R. China
| | - Yong Fang
- State Key Laboratory of Coordination Chemistry, Jiangsu Key Laboratory of Advanced Organic Materials, School of Chemistry and Chemical Engineering, Collaborative Innovation Center of Advanced Microstructures, Nanjing University, Nanjing, 210023, P. R. China
| | - Huapeng Ruan
- State Key Laboratory of Coordination Chemistry, Jiangsu Key Laboratory of Advanced Organic Materials, School of Chemistry and Chemical Engineering, Collaborative Innovation Center of Advanced Microstructures, Nanjing University, Nanjing, 210023, P. R. China
| | - Yue Zhao
- State Key Laboratory of Coordination Chemistry, Jiangsu Key Laboratory of Advanced Organic Materials, School of Chemistry and Chemical Engineering, Collaborative Innovation Center of Advanced Microstructures, Nanjing University, Nanjing, 210023, P. R. China
| | - Gengwen Tan
- State Key Laboratory of Coordination Chemistry, Jiangsu Key Laboratory of Advanced Organic Materials, School of Chemistry and Chemical Engineering, Collaborative Innovation Center of Advanced Microstructures, Nanjing University, Nanjing, 210023, P. R. China.,College of Chemistry, Chemical Engineering and Materials Science, Soochow University, Suzhou, 215123, P. R. China
| | - Xinping Wang
- State Key Laboratory of Coordination Chemistry, Jiangsu Key Laboratory of Advanced Organic Materials, School of Chemistry and Chemical Engineering, Collaborative Innovation Center of Advanced Microstructures, Nanjing University, Nanjing, 210023, P. R. China
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32
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Hermann A, Arrowsmith M, Trujillo-Gonzalez DE, Jiménez-Halla JOC, Vargas A, Braunschweig H. Trapping of a Borirane Intermediate in the Reductive Coupling of an Arylborane to a Diborene. J Am Chem Soc 2020; 142:5562-5567. [DOI: 10.1021/jacs.0c02306] [Citation(s) in RCA: 13] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/02/2023]
Affiliation(s)
- Alexander Hermann
- Institute for Inorganic Chemistry and Institute for Sustainable Chemistry & Catalysis with Boron, Julius-Maximilians-Universität Wüzburg, Am Hubland, 97074 Würzburg, Germany
| | - Merle Arrowsmith
- Institute for Inorganic Chemistry and Institute for Sustainable Chemistry & Catalysis with Boron, Julius-Maximilians-Universität Wüzburg, Am Hubland, 97074 Würzburg, Germany
| | - Daniel E. Trujillo-Gonzalez
- Departamento de Química, División de Ciencias Naturales y Exactas, Universidad de Guanajuato, Noria Alta S/N, Col. Noria Alta, 36050 Guanajuato, GTO, Mexico
| | - J. Oscar C. Jiménez-Halla
- Departamento de Química, División de Ciencias Naturales y Exactas, Universidad de Guanajuato, Noria Alta S/N, Col. Noria Alta, 36050 Guanajuato, GTO, Mexico
| | - Alfredo Vargas
- Department of Chemistry, School of Life Sciences, University of Sussex, Brighton BN1 9QJ, Sussex, United Kingdom
| | - Holger Braunschweig
- Institute for Inorganic Chemistry and Institute for Sustainable Chemistry & Catalysis with Boron, Julius-Maximilians-Universität Wüzburg, Am Hubland, 97074 Würzburg, Germany
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33
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Tang B, Zhao J, Xu JF, Zhang X. Tuning the stability of organic radicals: from covalent approaches to non-covalent approaches. Chem Sci 2020; 11:1192-1204. [PMID: 34123243 PMCID: PMC8148027 DOI: 10.1039/c9sc06143f] [Citation(s) in RCA: 85] [Impact Index Per Article: 21.3] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/05/2019] [Accepted: 12/26/2019] [Indexed: 12/22/2022] Open
Abstract
Organic radicals are important species with single electrons. Because of their open-shell structure, they are widely used in functional materials, such as spin probes, magnetic materials and optoelectronic materials. Owing to the high reactivity of single electrons, they often serve as a key intermediate in organic synthesis. Therefore, tuning the stability of radicals is crucial for their functions. Herein, we summarize covalent and non-covalent approaches to tune the stability of organic radicals through steric effects and tuning the delocalization of spin density. Covalent approaches can tune the stability of radicals effectively and non-covalent approaches benefit from dynamicity and reversibility. It is anticipated that the further development of covalent and non-covalent approaches, as well as the interplay between them, may push the fields forward by enriching new radical materials and radical mediated reactions.
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Affiliation(s)
- Bohan Tang
- Key Laboratory of Organic Optoelectronics & Molecular Engineering, Department of Chemistry, Tsinghua University Beijing 100084 China
| | - Jiantao Zhao
- Key Laboratory of Organic Optoelectronics & Molecular Engineering, Department of Chemistry, Tsinghua University Beijing 100084 China
| | - Jiang-Fei Xu
- Key Laboratory of Organic Optoelectronics & Molecular Engineering, Department of Chemistry, Tsinghua University Beijing 100084 China
| | - Xi Zhang
- Key Laboratory of Organic Optoelectronics & Molecular Engineering, Department of Chemistry, Tsinghua University Beijing 100084 China
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34
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Schmidt U, Fantuzzi F, Arrowsmith M, Hermann A, Prieschl D, Rempel A, Engels B, Braunschweig H. Tuneable reduction of cymantrenylboranes to diborenes or borylene-derived boratafulvenes. Chem Commun (Camb) 2020; 56:14809-14812. [DOI: 10.1039/d0cc06398c] [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
By switching the reaction conditions, the reduction of a N-heterocyclic carbene-stabilised cymantrenyldibromoborane can be tuned to yield either the corresponding diborene or borylene, the latter being stabilised through a boratafulvene conformation.
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Affiliation(s)
- Uwe Schmidt
- Institute for Inorganic Chemistry
- Julius-Maximilians-Universität Würzburg
- Am Hubland
- Germany
- Institute for Sustainable Chemistry & Catalysis with Boron
| | - Felipe Fantuzzi
- Institute for Inorganic Chemistry
- Julius-Maximilians-Universität Würzburg
- Am Hubland
- Germany
- Institute for Sustainable Chemistry & Catalysis with Boron
| | - Merle Arrowsmith
- Institute for Inorganic Chemistry
- Julius-Maximilians-Universität Würzburg
- Am Hubland
- Germany
- Institute for Sustainable Chemistry & Catalysis with Boron
| | - Alexander Hermann
- Institute for Inorganic Chemistry
- Julius-Maximilians-Universität Würzburg
- Am Hubland
- Germany
- Institute for Sustainable Chemistry & Catalysis with Boron
| | - Dominic Prieschl
- Institute for Inorganic Chemistry
- Julius-Maximilians-Universität Würzburg
- Am Hubland
- Germany
- Institute for Sustainable Chemistry & Catalysis with Boron
| | - Anna Rempel
- Institute for Inorganic Chemistry
- Julius-Maximilians-Universität Würzburg
- Am Hubland
- Germany
- Institute for Sustainable Chemistry & Catalysis with Boron
| | - Bernd Engels
- Institute for Physical and Theoretical Chemistry
- Julius-Maximilians-Universität Würzburg
- 97074 Würzburg
- Germany
| | - Holger Braunschweig
- Institute for Inorganic Chemistry
- Julius-Maximilians-Universität Würzburg
- Am Hubland
- Germany
- Institute for Sustainable Chemistry & Catalysis with Boron
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35
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Tavakol H, Ranjbari MA, Jafari-Chermahini MT. Mechanistic details for the reaction of methyl acrylate radical anion: a DFT study. REACTION KINETICS MECHANISMS AND CATALYSIS 2019. [DOI: 10.1007/s11144-019-01647-0] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
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36
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Borthakur R, Saha K, Kar S, Ghosh S. Recent advances in transition metal diborane(6), diborane(4) and diborene(2) chemistry. Coord Chem Rev 2019. [DOI: 10.1016/j.ccr.2019.213021] [Citation(s) in RCA: 22] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
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37
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Hupf E, Tsuchiya Y, Moffat W, Xu L, Hirai M, Zhou Y, Ferguson MJ, McDonald R, Murai T, He G, Rivard E. A Modular Approach to Phosphorescent π-Extended Heteroacenes. Inorg Chem 2019; 58:13323-13336. [PMID: 31503465 DOI: 10.1021/acs.inorgchem.9b02213] [Citation(s) in RCA: 17] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
A modular route to previously inaccessible classes of ring-fused π-extended heteroacenes bearing the heavy inorganic element tellurium (Te) is presented. These new materials can be viewed as n-doped analogs of molecular graphene subunits that exhibit color tunable visible light phosphorescence in the solid state and in the presence of air. The general mechanism of phosphorescence in these systems was probed experimentally and computationally via time-dependent density functional theory (TD-DFT). The incorporation of Te into π-extended oligoacene frameworks was achieved by an efficient Zr/Te transmetalation protocol; related zirconium-element exchange reactions have been used to prepare both electron-rich and electron-deficient heterocycles containing different elements from throughout the p-block. Therefore, the current study provides a clear path to incorporate inorganic elements into heteroacenes of greater complexity and side group selectivity compared to existing synthetic routes.
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Affiliation(s)
- Emanuel Hupf
- Department of Chemistry , University of Alberta , 11227 Saskatchewan Drive , Edmonton , Alberta T6G 2G2 , Canada
| | - Yuki Tsuchiya
- Department of Chemistry , University of Alberta , 11227 Saskatchewan Drive , Edmonton , Alberta T6G 2G2 , Canada.,Department of Chemistry and Biomolecular Science, Faculty of Engineering , Gifu University , Yanagido , Gifu 501-1193 , Japan
| | - Wayne Moffat
- Department of Chemistry , University of Alberta , 11227 Saskatchewan Drive , Edmonton , Alberta T6G 2G2 , Canada
| | - Letian Xu
- Frontier Institute of Science and Technology , Xi'an Jiaotong University , Xi'an , Shaanxi Province 710054 , China
| | - Masato Hirai
- Department of Chemistry, Graduate School of Science, Institute of Transformative Bio-Molecules (WPI-ITbM), and Integrated Research Consortium on Chemical Sciences (IRCCS) , Nagoya University , Furo, Chikusa, Nagoya 464-8602 , Japan
| | - Yuqiao Zhou
- Department of Chemistry , University of Alberta , 11227 Saskatchewan Drive , Edmonton , Alberta T6G 2G2 , Canada
| | - Michael J Ferguson
- Department of Chemistry , University of Alberta , 11227 Saskatchewan Drive , Edmonton , Alberta T6G 2G2 , Canada
| | - Robert McDonald
- Department of Chemistry , University of Alberta , 11227 Saskatchewan Drive , Edmonton , Alberta T6G 2G2 , Canada
| | - Toshiaki Murai
- Department of Chemistry and Biomolecular Science, Faculty of Engineering , Gifu University , Yanagido , Gifu 501-1193 , Japan
| | - Gang He
- Frontier Institute of Science and Technology , Xi'an Jiaotong University , Xi'an , Shaanxi Province 710054 , China
| | - Eric Rivard
- Department of Chemistry , University of Alberta , 11227 Saskatchewan Drive , Edmonton , Alberta T6G 2G2 , Canada
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38
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Akiyama S, Yamada K, Yamashita M. Reactivity of a Tetra(o-tolyl)diborane(4) Dianion as a Diarylboryl Anion Equivalent. Angew Chem Int Ed Engl 2019; 58:11806-11810. [PMID: 31264753 DOI: 10.1002/anie.201907400] [Citation(s) in RCA: 17] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/13/2019] [Indexed: 12/17/2022]
Abstract
Lithium and magnesium salts of tetra(o-tolyl)diborane(4) dianion, having B=B double bond character, were synthesized. It was clarified that the lithium salt of the dianion has a high-lying HOMO and a narrow HOMO-LUMO gap, which were perturbed by dissociation of Li+ cation, as judged by UV/Vis spectroscopy and DFT calculations. The lithium salt of the dianion reacted as two equivalents of a diarylboryl anion with CH2 Cl2 or S8 to give boryl-substituted products.
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Affiliation(s)
- Seiji Akiyama
- Department of Molecular and Macromolecular Chemistry, Graduate School of Engineering, Nagoya University, Furo-cho, Chikusa-ku, Nagoya, 464-8603, Aichi, Japan
| | - Kaito Yamada
- Department of Molecular and Macromolecular Chemistry, Graduate School of Engineering, Nagoya University, Furo-cho, Chikusa-ku, Nagoya, 464-8603, Aichi, Japan
| | - Makoto Yamashita
- Department of Molecular and Macromolecular Chemistry, Graduate School of Engineering, Nagoya University, Furo-cho, Chikusa-ku, Nagoya, 464-8603, Aichi, Japan
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39
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Prieschl D, Dietz M, Muessig JH, Wagner K, Krummenacher I, Braunschweig H. Pseudodiborenes: hydride-bridged diboranes(5) as two-electron reductants of chalcogens. Chem Commun (Camb) 2019; 55:9781-9784. [PMID: 31355376 DOI: 10.1039/c9cc04692e] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/02/2023]
Abstract
The reactivity of two nucleophilic neutral sp2-sp3 diboranes towards chalcogens is presented herein. Both diboranes(5) serve as two-electron reductants, incorporating oxygen, sulfur and selenium atoms. Treatment with chalcogen sources results in the oxidative insertion of one chalcogen atom into the B-B single bond, while depending on the negative inductive effect of the chalcogen and the boron bound aryl substituent further N-heterocyclic carbene (NHC) ring expansion and hydride migration can occur. These reactions provide access to unprecedented six- or seven-membered heterocycles and help to illuminate the pseudo-multiple bonding character of hydrogen-bridged B-B single bonds.
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Affiliation(s)
- Dominic Prieschl
- Institut für Anorganische Chemie, Julius-Maximilians-Universität Würzburg, Am Hubland, 97074, Würzburg, Germany.
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40
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Akiyama S, Yamada K, Yamashita M. Reactivity of a Tetra(
o
‐tolyl)diborane(4) Dianion as a Diarylboryl Anion Equivalent. Angew Chem Int Ed Engl 2019. [DOI: 10.1002/ange.201907400] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/16/2023]
Affiliation(s)
- Seiji Akiyama
- Department of Molecular and Macromolecular Chemistry Graduate School of Engineering Nagoya University, Furo-cho, Chikusa-ku Nagoya 464-8603 Aichi Japan
| | - Kaito Yamada
- Department of Molecular and Macromolecular Chemistry Graduate School of Engineering Nagoya University, Furo-cho, Chikusa-ku Nagoya 464-8603 Aichi Japan
| | - Makoto Yamashita
- Department of Molecular and Macromolecular Chemistry Graduate School of Engineering Nagoya University, Furo-cho, Chikusa-ku Nagoya 464-8603 Aichi Japan
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41
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Feng R, Zhang L, Ruan H, Zhao Y, Tan G, Wang X. A Main‐Group Element Radical Based One‐Dimensional Magnetic Chain. Angew Chem Int Ed Engl 2019. [DOI: 10.1002/ange.201901177] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/03/2023]
Affiliation(s)
- Rui Feng
- State Key Laboratory of Coordination ChemistryJiangsu Key Laboratory of Advanced Organic MaterialsSchool of Chemistry and Chemical EngineeringCollaborative Innovation Center of Advanced MicrostructuresNanjing University Nanjing 210023 China
| | - Li Zhang
- State Key Laboratory of Coordination ChemistryJiangsu Key Laboratory of Advanced Organic MaterialsSchool of Chemistry and Chemical EngineeringCollaborative Innovation Center of Advanced MicrostructuresNanjing University Nanjing 210023 China
| | - Huapeng Ruan
- State Key Laboratory of Coordination ChemistryJiangsu Key Laboratory of Advanced Organic MaterialsSchool of Chemistry and Chemical EngineeringCollaborative Innovation Center of Advanced MicrostructuresNanjing University Nanjing 210023 China
| | - Yue Zhao
- State Key Laboratory of Coordination ChemistryJiangsu Key Laboratory of Advanced Organic MaterialsSchool of Chemistry and Chemical EngineeringCollaborative Innovation Center of Advanced MicrostructuresNanjing University Nanjing 210023 China
| | - Gengwen Tan
- State Key Laboratory of Coordination ChemistryJiangsu Key Laboratory of Advanced Organic MaterialsSchool of Chemistry and Chemical EngineeringCollaborative Innovation Center of Advanced MicrostructuresNanjing University Nanjing 210023 China
| | - Xinping Wang
- State Key Laboratory of Coordination ChemistryJiangsu Key Laboratory of Advanced Organic MaterialsSchool of Chemistry and Chemical EngineeringCollaborative Innovation Center of Advanced MicrostructuresNanjing University Nanjing 210023 China
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42
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Feng R, Zhang L, Ruan H, Zhao Y, Tan G, Wang X. A Main-Group Element Radical Based One-Dimensional Magnetic Chain. Angew Chem Int Ed Engl 2019; 58:6084-6088. [PMID: 30784151 DOI: 10.1002/anie.201901177] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/28/2019] [Indexed: 01/03/2023]
Abstract
The first main-group element radical based one-dimensional magnetic chain (1K)n was realized by one-electron reduction of the pyridinyl functionalized borane 1 with elemental potassium in THF in the absence of 18-crown-6 (18-c-6). The electron spin density of (1K)n mainly resides at the boron centers with a considerable contribution from central benzene and pyridine moieties. The spin centers exhibit an antiferromagnetic interaction as demonstrated by magnetic measurements and theoretical calculations. In contrast, the reduction in the presence of 18-c-6 afforded the separated radical anion salt 1K(Crown), in which the potassium cation was trapped by THF and 18-c-6 molecules. Further one-electron reduction of 1K(Crown) and (1K)n led to the diamagnetic monomer and polymer, respectively.
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Affiliation(s)
- Rui Feng
- State Key Laboratory of Coordination Chemistry, Jiangsu Key Laboratory of Advanced Organic Materials, School of Chemistry and Chemical Engineering, Collaborative Innovation Center of Advanced Microstructures, Nanjing University, Nanjing, 210023, China
| | - Li Zhang
- State Key Laboratory of Coordination Chemistry, Jiangsu Key Laboratory of Advanced Organic Materials, School of Chemistry and Chemical Engineering, Collaborative Innovation Center of Advanced Microstructures, Nanjing University, Nanjing, 210023, China
| | - Huapeng Ruan
- State Key Laboratory of Coordination Chemistry, Jiangsu Key Laboratory of Advanced Organic Materials, School of Chemistry and Chemical Engineering, Collaborative Innovation Center of Advanced Microstructures, Nanjing University, Nanjing, 210023, China
| | - Yue Zhao
- State Key Laboratory of Coordination Chemistry, Jiangsu Key Laboratory of Advanced Organic Materials, School of Chemistry and Chemical Engineering, Collaborative Innovation Center of Advanced Microstructures, Nanjing University, Nanjing, 210023, China
| | - Gengwen Tan
- State Key Laboratory of Coordination Chemistry, Jiangsu Key Laboratory of Advanced Organic Materials, School of Chemistry and Chemical Engineering, Collaborative Innovation Center of Advanced Microstructures, Nanjing University, Nanjing, 210023, China
| | - Xinping Wang
- State Key Laboratory of Coordination Chemistry, Jiangsu Key Laboratory of Advanced Organic Materials, School of Chemistry and Chemical Engineering, Collaborative Innovation Center of Advanced Microstructures, Nanjing University, Nanjing, 210023, China
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43
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Pal A, Ahmad K, Dutta D, Chattopadhyay A. Boron Doped Carbon Dots with Unusually High Photoluminescence Quantum Yield for Ratiometric Intracellular pH Sensing. Chemphyschem 2019; 20:1018-1027. [DOI: 10.1002/cphc.201900140] [Citation(s) in RCA: 27] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/12/2019] [Revised: 03/13/2019] [Indexed: 01/09/2023]
Affiliation(s)
- Ayan Pal
- Department of ChemistryIndian Institute of Technology Guwahati Guwahati- 781039, Assam India
| | - Kafeel Ahmad
- Department of ChemistryIndian Institute of Technology Guwahati Guwahati- 781039, Assam India
| | - Deepanjalee Dutta
- Centre for NanotechnologyIndian Institute of Technology Guwahati Guwahati- 781039, Assam India
| | - Arun Chattopadhyay
- Department of ChemistryIndian Institute of Technology Guwahati Guwahati- 781039, Assam India
- Centre for NanotechnologyIndian Institute of Technology Guwahati Guwahati- 781039, Assam India
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44
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Kundu S, Sinhababu S, Chandrasekhar V, Roesky HW. Stable cyclic (alkyl)(amino)carbene (cAAC) radicals with main group substituents. Chem Sci 2019; 10:4727-4741. [PMID: 31160949 PMCID: PMC6510188 DOI: 10.1039/c9sc01351b] [Citation(s) in RCA: 89] [Impact Index Per Article: 17.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/19/2019] [Accepted: 04/06/2019] [Indexed: 11/21/2022] Open
Abstract
Recent attempts to isolate cyclic (alkyl)(amino)carbene stabilized radicals of p-block elements have been described here.
Isolation and characterization of stable radicals has been a long-pursued quest. While there has been some progress in this field particularly with respect to carbon, radicals involving heavier p-block elements are still considerably sparse. In this review we describe our recent successful efforts on the isolation of stable p-block element radicals particularly those involving aluminum, silicon, and phosphorus.
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Affiliation(s)
- Subrata Kundu
- Universität Göttingen , Institut für Anorganische Chemie , Tammannstrasse 4 , D-37077 , Göttingen , Germany .
| | - Soumen Sinhababu
- Universität Göttingen , Institut für Anorganische Chemie , Tammannstrasse 4 , D-37077 , Göttingen , Germany .
| | - Vadapalli Chandrasekhar
- Universität Göttingen , Institut für Anorganische Chemie , Tammannstrasse 4 , D-37077 , Göttingen , Germany . .,Tata Institute of Fundamental Research Hyderabad , Hyderabad 500107 , India.,Department of Chemistry , Indian Institute of Technology Kanpur , Kanpur 208016 , India .
| | - Herbert W Roesky
- Universität Göttingen , Institut für Anorganische Chemie , Tammannstrasse 4 , D-37077 , Göttingen , Germany .
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45
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Deissenberger A, Welz E, Drescher R, Krummenacher I, Dewhurst RD, Engels B, Braunschweig H. A New Class of Neutral Boron‐Based Diradicals Spanned by a Two‐Carbon‐Atom Bridge. Angew Chem Int Ed Engl 2019; 58:1842-1846. [DOI: 10.1002/anie.201813335] [Citation(s) in RCA: 20] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/22/2018] [Indexed: 11/12/2022]
Affiliation(s)
- Andrea Deissenberger
- Institute for Inorganic ChemistryJulius-Maximilians-Universität Würzburg Am Hubland 97074 Würzburg Germany
- Institute for Sustainable Chemistry & Catalysis with BoronJulius-Maximilians-Universität Würzburg Am Hubland 97074 Würzburg Germany
| | - Eileen Welz
- Institute for Physical and Theoretical ChemistryJulius-Maximilians-Universität Würzburg Am Hubland 97074 Würzburg Germany
| | - Regina Drescher
- Institute for Inorganic ChemistryJulius-Maximilians-Universität Würzburg Am Hubland 97074 Würzburg Germany
- Institute for Sustainable Chemistry & Catalysis with BoronJulius-Maximilians-Universität Würzburg Am Hubland 97074 Würzburg Germany
| | - Ivo Krummenacher
- Institute for Inorganic ChemistryJulius-Maximilians-Universität Würzburg Am Hubland 97074 Würzburg Germany
- Institute for Sustainable Chemistry & Catalysis with BoronJulius-Maximilians-Universität Würzburg Am Hubland 97074 Würzburg Germany
| | - Rian D. Dewhurst
- Institute for Inorganic ChemistryJulius-Maximilians-Universität Würzburg Am Hubland 97074 Würzburg Germany
- Institute for Sustainable Chemistry & Catalysis with BoronJulius-Maximilians-Universität Würzburg Am Hubland 97074 Würzburg Germany
| | - Bernd Engels
- Institute for Physical and Theoretical ChemistryJulius-Maximilians-Universität Würzburg Am Hubland 97074 Würzburg Germany
| | - Holger Braunschweig
- Institute for Inorganic ChemistryJulius-Maximilians-Universität Würzburg Am Hubland 97074 Würzburg Germany
- Institute for Sustainable Chemistry & Catalysis with BoronJulius-Maximilians-Universität Würzburg Am Hubland 97074 Würzburg Germany
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46
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Deissenberger A, Welz E, Drescher R, Krummenacher I, Dewhurst RD, Engels B, Braunschweig H. Eine neue Strukturklasse neutraler borhaltiger Diradikale verbrückt über zwei Kohlenstoffatome. Angew Chem Int Ed Engl 2019. [DOI: 10.1002/ange.201813335] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
Affiliation(s)
- Andrea Deissenberger
- Institut für Anorganische ChemieJulius-Maximilians-Universität Würzburg Am Hubland 97074 Würzburg Deutschland
- Institut für nachhaltige Chemie & Katalyse mit BorJulius-Maximilians-Universität Würzburg Am Hubland 97074 Würzburg Deutschland
| | - Eileen Welz
- Institut für Physikalische und Theoretische ChemieJulius-Maximilians-Universität Würzburg Am Hubland 97074 Würzburg Deutschland
| | - Regina Drescher
- Institut für Anorganische ChemieJulius-Maximilians-Universität Würzburg Am Hubland 97074 Würzburg Deutschland
- Institut für nachhaltige Chemie & Katalyse mit BorJulius-Maximilians-Universität Würzburg Am Hubland 97074 Würzburg Deutschland
| | - Ivo Krummenacher
- Institut für Anorganische ChemieJulius-Maximilians-Universität Würzburg Am Hubland 97074 Würzburg Deutschland
- Institut für nachhaltige Chemie & Katalyse mit BorJulius-Maximilians-Universität Würzburg Am Hubland 97074 Würzburg Deutschland
| | - Rian D. Dewhurst
- Institut für Anorganische ChemieJulius-Maximilians-Universität Würzburg Am Hubland 97074 Würzburg Deutschland
- Institut für nachhaltige Chemie & Katalyse mit BorJulius-Maximilians-Universität Würzburg Am Hubland 97074 Würzburg Deutschland
| | - Bernd Engels
- Institut für Physikalische und Theoretische ChemieJulius-Maximilians-Universität Würzburg Am Hubland 97074 Würzburg Deutschland
| | - Holger Braunschweig
- Institut für Anorganische ChemieJulius-Maximilians-Universität Würzburg Am Hubland 97074 Würzburg Deutschland
- Institut für nachhaltige Chemie & Katalyse mit BorJulius-Maximilians-Universität Würzburg Am Hubland 97074 Würzburg Deutschland
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47
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Yagi A, Kisu H, Yamashita M. Synthesis of a hydrogen-bridged tetraborane(6): a substituent effect of a diaminoboryl group toward the B–B multiple bond character. Dalton Trans 2019; 48:5496-5499. [DOI: 10.1039/c9dt01117j] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
Abstract
A hydrogen-bridging tetraborane(6) was synthesized from boryllithium, a boron nucleophile, in three steps.
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Affiliation(s)
- Atsumi Yagi
- Department of Molecular and Macromolecular Chemistry
- Graduate School of Engineering
- Nagoya University
- Nagoya
- Japan
| | - Haruki Kisu
- Department of Molecular and Macromolecular Chemistry
- Graduate School of Engineering
- Nagoya University
- Nagoya
- Japan
| | - Makoto Yamashita
- Department of Molecular and Macromolecular Chemistry
- Graduate School of Engineering
- Nagoya University
- Nagoya
- Japan
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48
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Feng R, Yang W, Wang W, Zhao Y, Tan G, Zhang L, Wang X. Isolable diboryl radicals acting as highly efficient reaction intermediates under mild conditions. Chem Commun (Camb) 2019; 55:12908-12911. [DOI: 10.1039/c9cc06514h] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Activation of the B–B bond in diborane with dimesitylpyridyl boranes afforded the stable diboryl radicals in moderate yields.
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Affiliation(s)
- Rui Feng
- State Key Laboratory of Coordination Chemistry
- School of Chemistry and Chemical Engineering
- Nanjing University
- Nanjing 210023
- China
| | - Wenbang Yang
- State Key Laboratory of Coordination Chemistry
- School of Chemistry and Chemical Engineering
- Nanjing University
- Nanjing 210023
- China
| | - Wenqing Wang
- State Key Laboratory of Coordination Chemistry
- School of Chemistry and Chemical Engineering
- Nanjing University
- Nanjing 210023
- China
| | - Yue Zhao
- State Key Laboratory of Coordination Chemistry
- School of Chemistry and Chemical Engineering
- Nanjing University
- Nanjing 210023
- China
| | - Gengwen Tan
- State Key Laboratory of Coordination Chemistry
- School of Chemistry and Chemical Engineering
- Nanjing University
- Nanjing 210023
- China
| | - Li Zhang
- State Key Laboratory of Coordination Chemistry
- School of Chemistry and Chemical Engineering
- Nanjing University
- Nanjing 210023
- China
| | - Xinping Wang
- State Key Laboratory of Coordination Chemistry
- School of Chemistry and Chemical Engineering
- Nanjing University
- Nanjing 210023
- China
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49
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Lu W, Xu K, Li Y, Hirao H, Kinjo R. Facile Activation of Homoatomic σ Bonds in White Phosphorus and Diborane by a Diboraallene. Angew Chem Int Ed Engl 2018. [DOI: 10.1002/ange.201808357] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/06/2023]
Affiliation(s)
- Wei Lu
- Division of Chemistry and Biological Chemistry; School of Physical and Mathematical Sciences; Nanyang Technological University; Nanyang Link 21 Singapore 637371 Singapore
| | - Kai Xu
- Department of Chemistry; City University of Hong Kong; Tat Chee Avenue, Kowloon Hong Kong China
| | - Yongxin Li
- Division of Chemistry and Biological Chemistry; School of Physical and Mathematical Sciences; Nanyang Technological University; Nanyang Link 21 Singapore 637371 Singapore
| | - Hajime Hirao
- Department of Chemistry; City University of Hong Kong; Tat Chee Avenue, Kowloon Hong Kong China
| | - Rei Kinjo
- Division of Chemistry and Biological Chemistry; School of Physical and Mathematical Sciences; Nanyang Technological University; Nanyang Link 21 Singapore 637371 Singapore
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50
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Lu W, Xu K, Li Y, Hirao H, Kinjo R. Facile Activation of Homoatomic σ Bonds in White Phosphorus and Diborane by a Diboraallene. Angew Chem Int Ed Engl 2018; 57:15691-15695. [DOI: 10.1002/anie.201808357] [Citation(s) in RCA: 27] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/21/2018] [Revised: 09/08/2018] [Indexed: 11/06/2022]
Affiliation(s)
- Wei Lu
- Division of Chemistry and Biological Chemistry; School of Physical and Mathematical Sciences; Nanyang Technological University; Nanyang Link 21 Singapore 637371 Singapore
| | - Kai Xu
- Department of Chemistry; City University of Hong Kong; Tat Chee Avenue, Kowloon Hong Kong China
| | - Yongxin Li
- Division of Chemistry and Biological Chemistry; School of Physical and Mathematical Sciences; Nanyang Technological University; Nanyang Link 21 Singapore 637371 Singapore
| | - Hajime Hirao
- Department of Chemistry; City University of Hong Kong; Tat Chee Avenue, Kowloon Hong Kong China
| | - Rei Kinjo
- Division of Chemistry and Biological Chemistry; School of Physical and Mathematical Sciences; Nanyang Technological University; Nanyang Link 21 Singapore 637371 Singapore
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