1
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Hu J, Xing X, Wang X. A Coppoborylene Stabilized by Multicenter Covalent Bonding and Its Amphoteric Reactivity to CO. Angew Chem Int Ed Engl 2024:e202403755. [PMID: 38797711 DOI: 10.1002/anie.202403755] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/23/2024] [Revised: 05/14/2024] [Accepted: 05/24/2024] [Indexed: 05/29/2024]
Abstract
A cationic copper-stabilized coppoborylene was prepared and structurally characterized via infrared photodissociation spectroscopy and density functional theory calculations. This structure exemplifies a new class of borylenes stabilized by three-center-two-electron metal-boron-metal covalent bonding interaction, displaying exceptional σ-acidity and unparalleled π-donor capability for CO activation that outperforms all of the known transition metal cations and is comparable or even superior to the documented base-trapped borylenes. Its neutral form represents a monovalent boron compound with a strongly reactive amphoteric boron center built on transition-metal-boron bonds, which inspires the design and synthesis of new members of the borylene family.
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Affiliation(s)
- Jin Hu
- School of Chemical Science and Engineering, Shanghai Key Lab of Chemical Assessment and Sustainability, Tongji University, 1239 Siping Road, Shanghai, 200092, P. R. China
| | - Xiaopeng Xing
- School of Chemical Science and Engineering, Shanghai Key Lab of Chemical Assessment and Sustainability, Tongji University, 1239 Siping Road, Shanghai, 200092, P. R. China
| | - Xuefeng Wang
- School of Chemical Science and Engineering, Shanghai Key Lab of Chemical Assessment and Sustainability, Tongji University, 1239 Siping Road, Shanghai, 200092, P. R. China
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2
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He M, Hu C, Wei R, Wang XF, Liu LL. Recent advances in the chemistry of isolable carbene analogues with group 13-15 elements. Chem Soc Rev 2024; 53:3896-3951. [PMID: 38436383 DOI: 10.1039/d3cs00784g] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 03/05/2024]
Abstract
Carbenes (R2C:), compounds with a divalent carbon atom containing only six valence shell electrons, have evolved into a broader class with the replacement of the carbene carbon or the RC moiety with main group elements, leading to the creation of main group carbene analogues. These analogues, mirroring the electronic structure of carbenes (a lone pair of electrons and an empty orbital), demonstrate unique reactivity. Over the last three decades, this area has seen substantial advancements, paralleling the innovations in carbene chemistry. Recent studies have revealed a spectrum of unique carbene analogues, such as monocoordinate aluminylenes, nitrenes, and bismuthinidenes, notable for their extraordinary properties and diverse reactivity, offering promising applications in small molecule activation. This review delves into the isolable main group carbene analogues that are in the forefront from 2010 and beyond, spanning elements from group 13 (B, Al, Ga, In, and Tl), group 14 (Si, Ge, Sn, and Pb) and group 15 (N, P, As, Sb, and Bi). Specifically, this review focuses on the potential amphiphilic species that possess both lone pairs of electrons and vacant orbitals. We detail their comprehensive synthesis and stabilization strategies, outlining the reactivity arising from their distinct structural characteristics.
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Affiliation(s)
- Mian He
- Department of Chemistry, Guangdong Provincial Key Laboratory of Catalysis and Research Center for Chemical Biology and Omics Analysis, College of Science, Southern University of Science and Technology, Shenzhen 518055, China.
| | - Chaopeng Hu
- Department of Chemistry, Guangdong Provincial Key Laboratory of Catalysis and Research Center for Chemical Biology and Omics Analysis, College of Science, Southern University of Science and Technology, Shenzhen 518055, China.
| | - Rui Wei
- Department of Chemistry, Guangdong Provincial Key Laboratory of Catalysis and Research Center for Chemical Biology and Omics Analysis, College of Science, Southern University of Science and Technology, Shenzhen 518055, China.
| | - Xin-Feng Wang
- Department of Chemistry, Guangdong Provincial Key Laboratory of Catalysis 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, Guangdong Provincial Key Laboratory of Catalysis and Research Center for Chemical Biology and Omics Analysis, College of Science, Southern University of Science and Technology, Shenzhen 518055, China.
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3
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Mao X, Qiu S, Guo R, Dai Y, Zhang J, Kong L, Xie Z. Cyclic (Alkyl)(Amino)Carbene-Iminoboryl Compounds with Three Formal Oxidation States. J Am Chem Soc 2024; 146:10917-10924. [PMID: 38587904 DOI: 10.1021/jacs.4c01934] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 04/10/2024]
Abstract
BN/CC isosterism is an effective strategy to build hybrid functional molecules with unique properties. In contrast to the alkynyl iminium salts derived from cyclic (alkyl)(amino)carbenes (CAACs) that feature only one reversible reduction wave, the isoelectronic cationic CAAC-iminoboryl adducts could be singly and doubly reduced smoothly. Both the resultant neutral radical and anionic azaborataallenes bear NBC-mixed allenic structures. The former radical has a high spin-density of 0.55e at CCAAC carbon, yet exhibits formal boron-centered radical reactivity. The latter azaborataallenes feature the nucleophilic CCAAC center and polar N(δ-)═B(δ+)═C(δ-) unit, and readily undergo nucleophilic substitution, isocyanide insertion, dipolar addition and cycloaddition reactions etc. The N-substituents have been shown to have a significant influence on the solid-state structure, thermal stability, and reactivity of azaborataallenes. This work showcases the allenic BN-unsaturated species as versatile building blocks in organic synthesis.
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Affiliation(s)
- Xiaofeng Mao
- Department of Chemistry and State Key Laboratory of Synthetic Chemistry, The Chinese University of Hong Kong, Shatin, New Territories, Hong Kong 999077, China
| | - Shuang Qiu
- School of Chemistry and Chemical Engineering, Shandong University, Jinan 250100, China
| | - Rui Guo
- School of Chemistry and Chemical Engineering, Shandong University, Jinan 250100, China
| | - Yuyang Dai
- School of Chemistry and Chemical Engineering, Shandong University, Jinan 250100, China
| | - Jie Zhang
- Department of Chemistry and State Key Laboratory of Synthetic Chemistry, The Chinese University of Hong Kong, Shatin, New Territories, Hong Kong 999077, China
| | - Lingbing Kong
- School of Chemistry and Chemical Engineering, Shandong University, Jinan 250100, China
| | - Zuowei Xie
- Department of Chemistry and State Key Laboratory of Synthetic Chemistry, The Chinese University of Hong Kong, Shatin, New Territories, Hong Kong 999077, China
- Shenzhen Grubbs Institute and Department of Chemistry, Southern University of Science and Technology, Shenzhen 518055, China
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4
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Witte R, Arrowsmith M, Lamprecht A, Schorr F, Krummenacher I, Braunschweig H. C-C and C-N Bond Activation, Lewis-Base Coordination and One- and Two-Electron Oxidation at a Linear Aminoborylene. Chemistry 2023; 29:e202203663. [PMID: 36562195 DOI: 10.1002/chem.202203663] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/24/2022] [Revised: 12/20/2022] [Accepted: 12/22/2022] [Indexed: 12/24/2022]
Abstract
A cyclic alkyl(amino)carbene (CAAC)-stabilized dicoordinate aminoborylene is synthesized by the twofold reduction of a [(CAAC)BCl2 (TMP)] (TMP=2,6-tetramethylpiperidyl) precursor. NMR-spectroscopic, X-ray crystallographic and computational analyses confirm the cumulenic nature of the central C=B=N moiety. Irradiation of [(CAAC)B(TMP)] (2) resulted in an intramolecular C-C bond activation, leading to a doubly-fused C10 BN heterocycle, while the reaction with acetonitrile resulted in an aryl migration from the CAAC to the acetonitrile nitrogen atom, concomitant with tautomerization of the latter to a boron-bound allylamino ligand. One-electron oxidation of 2 with CuX (X=Cl, Br) afforded the corresponding amino(halo)boryl radicals, which were characterized by EPR spectroscopy and DFT calculations. Placing 2 under an atmosphere of CO afforded the tricoordinate (CAAC,CO)-stabilized aminoborylene. Finally, the twofold oxidation of 2 with chalcogens led, in the case of N2 O and sulfur, to the splitting of the B-CCAAC bond and formation of the 2,4-diamino-1,3,2,4-dichalcogenadiboretanes and CAAC-chalcogen adducts, whereas with selenium a monomeric boraselenone was isolated, which showed some degree of B-Se multiple bonding.
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Affiliation(s)
- Robert Witte
- 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
| | - Anna Lamprecht
- 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
| | - Fabian Schorr
- 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
| | - 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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5
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Fan J, Yang MC, Su MD, So CW. N-Phosphinoamidinato Silylene- and Phosphine-Borylborylene Complexes. Inorg Chem 2023; 62:863-870. [PMID: 36600552 DOI: 10.1021/acs.inorgchem.2c03660] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/06/2023]
Abstract
This work describes a straightforward method to synthesize a borylborylene without proceeding via the rearrangement of a diborene. An amidinato amidosilylene [LSiNMe2] (L = PhC(NtBu)2) and PMe3 were reacted with an N-phosphinoamidinato diborane 1 and KC8 to form a stable silylene-borylborylene 2 and a persistent phosphine-borylborylene 3, respectively. Compound 2 is stable as the borylene center is well stabilized by the silylene donor and boryl substituent, whereas compound 3 is unstable in solution due to labile PMe3. The latter was illustrated by reacting compound 3 with Ar'NC (Ar' = 2,6-Me2C6H3), where Ar'NC displaced PMe3 and inserted into the N-phosphinoamidinate ligand and B-B bond to form compound 4.
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Affiliation(s)
- Jun Fan
- School of Chemistry, Chemical Engineering and Biotechnology, Nanyang Technological University, 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
- School of Chemistry, Chemical Engineering and Biotechnology, Nanyang Technological University, 637371 Singapore
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6
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Tian J, Cordier M, Bour C, Auffrant A, Gandon V. A cyclic divalent N(I) species isoelectronic to carbodiphosphoranes. Chem Commun (Camb) 2022; 58:5741-5744. [PMID: 35466973 DOI: 10.1039/d2cc01637k] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
The formation of a rare type of diphosphazenium cation is described. Its synthesis features a unique oxidative dealkylation of an iminophosphorane-phosphole by a silver(I) salt. DFT study of this compound reveals the low valent character of the N(I) center.
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Affiliation(s)
- Jiaxin Tian
- Institut de Chimie Moléculaire et des Matériaux d'Orsay, CNRS UMR 8182, Université Paris-Saclay, Bâtiment 420, 91405 Orsay cedex, France.
| | - Marie Cordier
- Laboratoire de Chimie Moléculaire (LCM), CNRS UMR 9168 Ecole Polytechnique, Institut Polytechnique de Paris, route de Saclay, 91120 Palaiseau, France.
| | - Christophe Bour
- Institut de Chimie Moléculaire et des Matériaux d'Orsay, CNRS UMR 8182, Université Paris-Saclay, Bâtiment 420, 91405 Orsay cedex, France.
| | - Audrey Auffrant
- Laboratoire de Chimie Moléculaire (LCM), CNRS UMR 9168 Ecole Polytechnique, Institut Polytechnique de Paris, route de Saclay, 91120 Palaiseau, France.
| | - Vincent Gandon
- Institut de Chimie Moléculaire et des Matériaux d'Orsay, CNRS UMR 8182, Université Paris-Saclay, Bâtiment 420, 91405 Orsay cedex, France. .,Laboratoire de Chimie Moléculaire (LCM), CNRS UMR 9168 Ecole Polytechnique, Institut Polytechnique de Paris, route de Saclay, 91120 Palaiseau, France.
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7
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Ghosh B, Cabrera-Trujillo JJ, Fernández I, Phukan AK. Stable N-heterocyclic borylenes with promising ligand properties: a contribution from theory. Inorg Chem Front 2022. [DOI: 10.1039/d2qi01511k] [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
DFT calculations reveal the power of ylides in stabilizing neutral singlet cyclic borylenes that are found to be capable of activating a variety of small molecules having enthalpically strong bonds.
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Affiliation(s)
- Bijoy Ghosh
- Department of Chemical Sciences, Tezpur University, Napam 784028, Assam, India
| | - Jorge Juan Cabrera-Trujillo
- Departamento de Química Orgánica I and Centro de Innovación en Química Avanzada (ORFEO-CINQA), Facultad de Ciencias Químicas, Universidad Complutense de Madrid, 28040-Madrid, Spain
| | - Israel Fernández
- Departamento de Química Orgánica I and Centro de Innovación en Química Avanzada (ORFEO-CINQA), Facultad de Ciencias Químicas, Universidad Complutense de Madrid, 28040-Madrid, Spain
| | - Ashwini K. Phukan
- Department of Chemical Sciences, Tezpur University, Napam 784028, Assam, India
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8
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Mikhaylov VN, Balova IA. Alternative Transformations of N-Heterocyclic Carbene Complexes of the Group 11 Metals in Transmetalation Reactions (A Review). RUSS J GEN CHEM+ 2021. [DOI: 10.1134/s1070363221110098] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
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9
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Gao H, Li Q, Cui P, Tung CH, Kong L. Facile Access to Alkylideneborane and Diborabutadiene N-Heterocyclic Carbene Complexes. Inorg Chem 2021; 60:8432-8436. [PMID: 34043317 DOI: 10.1021/acs.inorgchem.1c00866] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/07/2023]
Abstract
A facile route to synthesis of B═C double-bonded systems has been developed. Specifically, both dibromofluorenylborane (FluH-BBr2) and a 1,1-dibromo-2,2-difluorenyldiborane/dimethyl sulfide adduct [(FluH)2B-BBr2(SMe2)] could be smoothly dehydrobrominated and subsequently coordinated by N-heterocyclic carbenes (NHCs) with formation of the respective alkylideneborane 1 and diborabutadiene 3. The electronic structures of 1 and 3 are interrogated and compared with those of base-free counterparts through density functional theory calculations.
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Affiliation(s)
- Hao Gao
- School of Chemistry and Chemical Engineering, Shandong University, Jinan 250100, P. R. China
| | - Qianli Li
- School of Chemistry and Chemical Engineering, Liaocheng University, Liaocheng 252059, P. R. China
| | - Ping Cui
- School of Chemistry and Chemical Engineering, Shandong University, Jinan 250100, P. R. China
| | - Chen-Ho Tung
- School of Chemistry and Chemical Engineering, Shandong University, Jinan 250100, P. R. China
| | - Lingbing Kong
- School of Chemistry and Chemical Engineering, Shandong University, Jinan 250100, P. R. China
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10
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Yuvaraj K, Carpentier A, Smith CD, Maron L, Jones C. C-N and C-H Activation of an N-Heterocyclic Carbene by Magnesium(II) Hydride and Magnesium(I) Complexes. Inorg Chem 2021; 60:6065-6072. [PMID: 33793217 DOI: 10.1021/acs.inorgchem.1c00552] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/02/2023]
Abstract
Reactions of the hindered N-heterocyclic carbene, :C{(MesNCH)2} (IMes; Mes = mesityl), with a series of β-diketiminatomagnesium(II) hydride and dimagnesium(I) complexes were carried out at 80 °C. The reactions involving the magnesium hydrides, [{(ArNacnac)Mg(μ-H)}2] [ArNacnac = [(ArNCMe)2CH]-, where Ar = 2,6-diethylphenyl (Dep) or 2,6-diisopropylphenyl (Dip)], proceeded via activation of an exocyclic C-N bond of IMes, giving magnesium imidazolyl compounds [(ArNacnac)Mg(μ-H)(μ-Imid)Mg(ArNacnac)] (Imid = [NC2H2N(Mes)C]-) and mesitylene. A low-yield IMes methyl C-H activation product, [(DepNacnac)Mg(IMes-H)], was also obtained, via H2 elimination, from the reaction between IMes and [{(DepNacnac)Mg(μ-H)}2]. Reactions between IMes and dimagnesium(I) compounds [{(ArNacnac)Mg}2] [Ar = 2,6-dimethylphenyl (Xyl) or Mes] afforded isostructural C-H activation products [(ArNacnac)Mg(IMes-H)] but in higher yields. Density functional theory calculations suggest that the reactions do not progress via stable adduct complex intermediates, which are sterically inaccessible.
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Affiliation(s)
- K Yuvaraj
- School of Chemistry, Monash University, P.O. Box 23, Melbourne, Victoria 3800, Australia
| | - Ambre Carpentier
- Université de Toulouse, CNRS, INSA, UPS, UMR 5215, LPCNO, 135 Avenue de Rangueil, Toulouse F-31077, France
| | - Cory D Smith
- School of Chemistry, Monash University, P.O. Box 23, Melbourne, Victoria 3800, Australia
| | - Laurent Maron
- Université de Toulouse, CNRS, INSA, UPS, UMR 5215, LPCNO, 135 Avenue de Rangueil, Toulouse F-31077, France
| | - Cameron Jones
- School of Chemistry, Monash University, P.O. Box 23, Melbourne, Victoria 3800, Australia
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11
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Wu L, Dewhurst RD, Braunschweig H, Lin Z. C–C versus C–H Activation: Understanding How the Carbene π-Accepting Ability Controls the Intramolecular Reactivities of Mono(carbene)-Stabilized Borylenes. Organometallics 2021. [DOI: 10.1021/acs.organomet.1c00016] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Affiliation(s)
- Linlin Wu
- Department of Chemistry, The Hong Kong University of Science and Technology, Clear Water Bay, Kowloon, Hong Kong, China
| | - 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
| | - 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
| | - Zhenyang Lin
- Department of Chemistry, The Hong Kong University of Science and Technology, Clear Water Bay, Kowloon, Hong Kong, China
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12
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Abstract
AbstractOrganoboron compounds play prominent roles in structural, synthetic, and materials chemistry because boron atoms can feature electrophilic, ambiphilic, or nucleophilic character. This perspective briefly describes the most recent progress in organoboron chemistry, focusing on new boron molecules and their applications that have attracted great interest from main-group chemists. The research hotspots arising from these pioneering results are also discussed.1 Introduction2 Diboron Reagents3 Boryl Anions4 Borylenes5 Nucleophilic or Ambiphilic Boron-Containing N-Heterocycles6 Conclusions and Outlook
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Affiliation(s)
- Lingbing Kong
- School of Chemistry and Chemical Engineering, Shandong University
- State Key Laboratory of Elemento-organic Chemistry and College of Chemistry, Nankai University
| | - Chunming Cui
- State Key Laboratory of Elemento-organic Chemistry and College of Chemistry, Nankai University
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13
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Pranckevicius C, Weber M, Krummenacher I, Phukan AK, Braunschweig H. Phosphinoborylenes as stable sources of fleeting borylenes. Chem Sci 2020; 11:11055-11059. [PMID: 34123195 PMCID: PMC8162303 DOI: 10.1039/d0sc04826g] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/02/2020] [Accepted: 09/09/2020] [Indexed: 12/04/2022] Open
Abstract
Base-stabilised borylenes that mimic the ability of transition metals to bind and activate inert substrates have attracted significant attention in recent years. However, such species are typically highly reactive and fleeting, and often cannot be isolated at ambient temperature. Herein, we describe a readily accessible trimethylphosphine-stabilised borylborylene which was found to possess a labile P-B bond that reversibly cleaves upon gentle heating. Exchange of the labile phosphine with other nucleophiles (CO, isocyanide, 4-dimethylaminopyridine) was investigated, and the binding strength of a range of potential borylene "ligands" has been evaluated computationally. The room-temperature-stable PMe3-bound borylenes were subsequently applied to novel bond activations including [2 + 2] cycloaddition with carbodiimides and the reduction of dichalcogenides, revealing that PMe3-stabilised borylenes can effectively behave as stable sources of the analogous fleeting dicoordinate species under mild conditions.
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Affiliation(s)
- Conor Pranckevicius
- 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
| | - Marco Weber
- 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
| | - Ashwini K Phukan
- Department of Chemical Sciences, Tezpur University Napaam 784028 India
| | - 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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14
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Pranckevicius C, Herok C, Fantuzzi F, Engels B, Braunschweig H. Bindungsstärkende Rückbindung in Aminoborylen‐stabilisierten Aminoborylenen: an der Grenze zwischen Borylenen und Diborenen. Angew Chem Int Ed Engl 2019. [DOI: 10.1002/ange.201906671] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/25/2022]
Affiliation(s)
- Conor Pranckevicius
- Institut für anorganische Chemie Julius-Maximilians-Universität Würzburg Am Hubland 97074 Würzburg Deutschland
- Institut für nachhaltige Chemie und Katalyse mit Bor Julius-Maximilians-Universität Würzburg Am Hubland 97074 Würzburg Deutschland
| | - Christoph Herok
- Institut für anorganische Chemie Julius-Maximilians-Universität Würzburg Am Hubland 97074 Würzburg Deutschland
- Institut für nachhaltige Chemie und 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 und Katalyse mit Bor Julius-Maximilians-Universität Würzburg Am Hubland 97074 Würzburg Deutschland
- Institut für physikalische und theoretische Chemie Julius-Maximilians-Universität Würzburg Emil-Fischer Straße 42 97074 Würzburg Deutschland
| | - Bernd Engels
- Institut für physikalische und theoretische Chemie Julius-Maximilians-Universität Würzburg Emil-Fischer Straße 42 97074 Würzburg Deutschland
| | - Holger Braunschweig
- Institut für anorganische Chemie Julius-Maximilians-Universität Würzburg Am Hubland 97074 Würzburg Deutschland
- Institut für nachhaltige Chemie und Katalyse mit Bor Julius-Maximilians-Universität Würzburg Am Hubland 97074 Würzburg Deutschland
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15
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Pranckevicius C, Herok C, Fantuzzi F, Engels B, Braunschweig H. Bond-Strengthening Backdonation in Aminoborylene-Stabilized Aminoborylenes: At the Intersection of Borylenes and Diborenes. Angew Chem Int Ed Engl 2019; 58:12893-12897. [PMID: 31241232 DOI: 10.1002/anie.201906671] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/29/2019] [Indexed: 12/22/2022]
Abstract
Singly NHC-coordinated (aminoboryl)aminoborenium salts react with Na2 [Fe(CO)4 ] to yield stable coordination complexes of aminoborylene-stabilized aminoborylenes, which exhibit exceptional σ-donor properties. Upon photolytic CO extrusion from the metal center, the diboron ligand adopts a novel η3 -BBN coordination mode, where bond-strengthening backdonation from the metal center into the vacant B-B π-orbital is observed. This bonding situation can be alternatively described as a Fe-diaminodiborene complex. In a related reduction of CAAC-stabilized (aminoboryl)aminoborenium with KC8 , the reduced species can be captured with nucleophiles to form three-coordinate (diaminoboryl)borylenes, where both amino groups have migrated to the distal boron atom. Collectively, these reactions illustrate the isomeric flexibility imparted by amino groups on this reduced diboron system, thus opening multiple avenues of novel reactivity.
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Affiliation(s)
- Conor Pranckevicius
- 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
| | - Christoph Herok
- 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.,Institute for Physical and Theoretical Chemistry, Julius-Maximilians-Universität Würzburg, Emil-Fischer Strasse 42, 97074, Würzburg, Germany
| | - Bernd Engels
- Institute for Physical and Theoretical Chemistry, Julius-Maximilians-Universität Würzburg, Emil-Fischer Strasse 42, 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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16
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Franz D, Szilvási T, Pöthig A, Inoue S. Isolation of an N‐Heterocyclic Carbene Complex of a Borasilene. Chemistry 2019; 25:11036-11041. [DOI: 10.1002/chem.201902877] [Citation(s) in RCA: 40] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/22/2019] [Indexed: 12/11/2022]
Affiliation(s)
- Daniel Franz
- Department of ChemistryCatalysis Research Center and Institute of Silicon ChemistryTechnische Universität München Lichtenbergstrasse 4 85748 Garching bei München Germany
| | - Tibor Szilvási
- Department of Chemical and Biological EngineeringUniversity of Wisconsin-Madison 1415 Engineering Drive Madison WI 53706-1607 USA
| | - Alexander Pöthig
- Department of ChemistryCatalysis Research Center and Institute of Silicon ChemistryTechnische Universität München Lichtenbergstrasse 4 85748 Garching bei München Germany
| | - Shigeyoshi Inoue
- Department of ChemistryCatalysis Research Center and Institute of Silicon ChemistryTechnische Universität München Lichtenbergstrasse 4 85748 Garching bei München Germany
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17
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Hofmann A, Pranckevicius C, Tröster T, Braunschweig H. Redoxreaktionen zwischen Aluminium(I)- und Bor(III)-Verbindungen. Angew Chem Int Ed Engl 2019. [DOI: 10.1002/ange.201813619] [Citation(s) in RCA: 17] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
Affiliation(s)
- Alexander Hofmann
- Institut für Anorganische Chemie; Julius-Maximilians-Universität Würzburg; Am Hubland 97074 Würzburg Deutschland
- Institute for Sustainable Chemistry & Catalysis with Boron; Julius-Maximilians-Universität Würzburg; Am Hubland 97074 Würzburg Deutschland
| | - Conor Pranckevicius
- Institut für Anorganische Chemie; Julius-Maximilians-Universität Würzburg; Am Hubland 97074 Würzburg Deutschland
- Institute for Sustainable Chemistry & Catalysis with Boron; Julius-Maximilians-Universität Würzburg; Am Hubland 97074 Würzburg Deutschland
| | - Tobias Tröster
- Institut für Anorganische Chemie; Julius-Maximilians-Universität Würzburg; Am Hubland 97074 Würzburg Deutschland
- Institute for Sustainable Chemistry & Catalysis with Boron; Julius-Maximilians-Universität Würzburg; Am Hubland 97074 Würzburg Deutschland
| | - Holger Braunschweig
- Institut für Anorganische Chemie; Julius-Maximilians-Universität Würzburg; Am Hubland 97074 Würzburg Deutschland
- Institute for Sustainable Chemistry & Catalysis with Boron; Julius-Maximilians-Universität Würzburg; Am Hubland 97074 Würzburg Deutschland
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18
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Hofmann A, Pranckevicius C, Tröster T, Braunschweig H. Aluminum(I)/Boron(III) Redox Reactions. Angew Chem Int Ed Engl 2019; 58:3625-3629. [DOI: 10.1002/anie.201813619] [Citation(s) in RCA: 29] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/29/2018] [Indexed: 11/10/2022]
Affiliation(s)
- Alexander Hofmann
- 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
| | - Conor Pranckevicius
- 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
| | - Tobias Tröster
- 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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19
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Abstract
The study of main-group molecules that behave and react similarly to transition-metal (TM) complexes has attracted significant interest in recent decades. Most notably, the attractive idea of replacing the all-too-often rare and costly metals from catalysis has motivated efforts to develop main-group-element-mediated reactions. Main-group elements, however, lack the electronic flexibility of TM complexes that arises from combinations of empty and filled d orbitals and that seem ideally suited to bind and activate many substrates. In this review, we look at boron, an element that despite its nonmetal nature, low atomic weight, and relative redox staticity has achieved great milestones in terms of TM-like reactivity. We show how in interelement cooperative systems, diboron molecules, and hypovalent complexes the fifth element can acquire a truly metallomimetic character. As we discuss, this character is powerfully demonstrated by the reactivity of boron-based molecules with H2, CO, alkynes, alkenes and even with N2.
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