1
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Patra SG. Asymmetric catalysis by chiral FLPs: A computational mini-review. Chirality 2024; 36:e23671. [PMID: 38660756 DOI: 10.1002/chir.23671] [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: 01/28/2024] [Revised: 03/21/2024] [Accepted: 04/07/2024] [Indexed: 04/26/2024]
Abstract
Steric hindrance in Lewis acid (LA) and Lewis base (LB) obstruct the Lewis acid-base adduct formation, and the pair was termed as frustrated Lewis pair (FLP). In the past 16 years, the field of enantioselective catalysis by chiral FLPs has been slowly growing. It was shown that chiral LAs are significant as they are involved in the hydrogen transfer (HT) step to the imine, resulting in enantioselectivity. After H2 activation, the borohydride can exist in a number of plausible conformations and their stability is governed by the presence of noncovalent interaction through C-H····π and π····π interactions. However, LBs are not ideal for asymmetric induction as they compete with the imine substrate as a counter LB. Further, the proton transfer from chiral LB to the imine does not induce any chirality as chirality develops in the HT step. However, intramolecular FLPs with chiral scaffold are very efficient as they possess an optimum distance between LA and LB, which facilitates the H2 activation but precludes the adduct formation of the small molecules substrate with the LA component. This mini-review summarizes computational investigation involving chiral LA and LB, and discusses intramolecular FLPs in the enantioselective catalysis.
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Affiliation(s)
- Shanti Gopal Patra
- Department of Chemistry, National Institute of Technology Silchar, Silchar, India
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2
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Abstract
Chiral catalysts play a crucial role in the realm of asymmetric catalysis. Since their breakthrough discovery in 2006, chiral frustrated Lewis pairs (FLPs) have risen as a novel catalyst category for a broad range of metal-free asymmetric reactions. This review provides an overview of the remarkable progress made in this field over the past 15 years. The design and synthesis of chiral FLPs and their applications in hydrogenation, hydrosilylation, transfer hydrogenation, and various other reactions are summarized and highlighted.
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Affiliation(s)
- Xiangqing Feng
- Beijing National Laboratory for Molecular Sciences, CAS Key Laboratory of Molecular Recognition and Function, Institute of Chemistry, Chinese Academy of Sciences, Beijing 100190, China.
- University of Chinese Academy of Sciences, Beijing 100049, China
| | - Wei Meng
- Beijing National Laboratory for Molecular Sciences, CAS Key Laboratory of Molecular Recognition and Function, Institute of Chemistry, Chinese Academy of Sciences, Beijing 100190, China.
- University of Chinese Academy of Sciences, Beijing 100049, China
| | - Haifeng Du
- Beijing National Laboratory for Molecular Sciences, CAS Key Laboratory of Molecular Recognition and Function, Institute of Chemistry, Chinese Academy of Sciences, Beijing 100190, China.
- University of Chinese Academy of Sciences, Beijing 100049, China
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3
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Abdou-Mohamed A, Aupic C, Fournet C, Parrain JL, Chouraqui G, Chuzel O. Stereoselective formation of boron-stereogenic organoboron derivatives. Chem Soc Rev 2023. [PMID: 37325998 DOI: 10.1039/d3cs00163f] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/17/2023]
Abstract
Four-coordinate organoboron derivatives present interesting chemical, physical, biological, electronical, and optical properties. Given the increasing demand for the synthesis of smart functional materials based on chiral organoboron compounds, the exploration of stereoselective synthesis of boron-stereogenic organo-derivatives is highly desirable. However, the stereoselective construction of organoboron compounds stereogenic at boron has been far less studied than other elements of the main group due to configurational stability concerns. Nowadays, these species are no longer elusive and configurationally stable compounds have been highlighted. The idea is to show the potential of the stereoselective building of the four-coordinate boron centre and encourage future endeavors and developments in the field.
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Affiliation(s)
| | - Clara Aupic
- Aix Marseille Univ, CNRS, Centrale Marseille, iSm2, Marseille, France.
| | - Corentin Fournet
- Aix Marseille Univ, CNRS, Centrale Marseille, iSm2, Marseille, France.
| | - Jean-Luc Parrain
- Aix Marseille Univ, CNRS, Centrale Marseille, iSm2, Marseille, France.
| | - Gaëlle Chouraqui
- Aix Marseille Univ, CNRS, Centrale Marseille, iSm2, Marseille, France.
| | - Olivier Chuzel
- Aix Marseille Univ, CNRS, Centrale Marseille, iSm2, Marseille, France.
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4
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Philipp MSM, Bertermann R, Radius U. Activation of Ge-H and Sn-H Bonds with N-Heterocyclic Carbenes and a Cyclic (Alkyl)(amino)carbene. Chemistry 2023; 29:e202202493. [PMID: 36177710 PMCID: PMC10100474 DOI: 10.1002/chem.202202493] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/10/2022] [Indexed: 01/14/2023]
Abstract
A study of the reactivity of several N-heterocyclic carbenes (NHCs) and the cyclic (alkyl)(amino)carbene 1-(2,6-di-iso-propylphenyl)-3,3,5,5-tetramethyl-pyrrolidin-2-ylidene (cAACMe ) with the group 14 hydrides GeH2 Mes2 and SnH2 Me2 (Me=CH3 , Mes=1,3,5-(CH3 )3 C6 H2 ) is presented. The reaction of GeH2 Mes2 with cAACMe led to the insertion of cAACMe into one Ge-H bond to give cAACMe H-GeHMes2 (1). If 1,3,4,5-tetramethyl-imidazolin-2-ylidene (Me2 ImMe ) was used as the carbene, NHC-mediated dehydrogenative coupling occurred, which led to the NHC-stabilized germylene Me2 ImMe ⋅GeMes2 (2). The reaction of SnH2 Me2 with cAACMe also afforded the insertion product cAACMe H-SnHMe2 (3), and reaction of two equivalents Me2 ImMe with SnH2 Me2 gave the NHC-stabilized stannylene Me2 ImMe ⋅SnMe2 (4). If the sterically more demanding NHCs Me2 ImMe , 1,3-di-isopropyl-4,5-dimethyl-imidazolin-2-ylidene (iPr2 ImMe ) and 1,3-bis-(2,6-di-isopropylphenyl)-imidazolin-2-ylidene (Dipp2 Im) were employed, selective formation of cyclic oligomers (SnMe2 )n (5; n=5-8) in high yield was observed. These cyclic oligomers were also obtained from the controlled decomposition of cAACMe H-SnHMe2 (3).
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Affiliation(s)
- Michael S M Philipp
- Institute of Inorganic Chemistry, Julius-Maximilians-Universität Würzburg, Am Hubland, 97074, Würzburg, Germany
| | - Rüdiger Bertermann
- Institute of Inorganic Chemistry, Julius-Maximilians-Universität Würzburg, Am Hubland, 97074, Würzburg, Germany
| | - Udo Radius
- Institute of Inorganic Chemistry, Julius-Maximilians-Universität Würzburg, Am Hubland, 97074, Würzburg, Germany
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5
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Zhang Y, Chen S, Al-Enizi AM, Nafady A, Tang Z, Ma S. Chiral Frustrated Lewis Pair@Metal-Organic Framework as a New Platform for Heterogeneous Asymmetric Hydrogenation. Angew Chem Int Ed Engl 2023; 62:e202213399. [PMID: 36347776 DOI: 10.1002/anie.202213399] [Citation(s) in RCA: 13] [Impact Index Per Article: 13.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/11/2022] [Indexed: 11/11/2022]
Abstract
Asymmetric hydrogenation, a seminal strategy for the synthesis of chiral molecules, remains largely unmet in terms of activation by non-metal sites of heterogeneous catalysts. Herein, as demonstrated by combined computational and experimental studies, we present a general strategy for integrating rationally designed molecular chiral frustrated Lewis pair (CFLP) with porous metal-organic framework (MOF) to construct the catalyst CFLP@MOF that can efficiently promote the asymmetric hydrogenation in a heterogeneous manner, which for the first time extends the concept of chiral frustrated Lewis pair from homogeneous system to heterogeneous catalysis. Significantly, the developed CFLP@MOF, inherits the merits of both homogeneous and heterogeneous catalysts, with high activity/enantio-selectivity and excellent recyclability/regenerability. Our work not only advances CFLP@MOF as a new platform for heterogeneous asymmetric hydrogenation, but also opens a new avenue for the design and preparation of advanced catalysts for asymmetric catalysis.
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Affiliation(s)
- Yin Zhang
- Department of Chemistry, University of North Texas, 1508 W Mulberry St, Denton, TX 76201, USA
| | - Songbo Chen
- School of Physical Science and Technology, Lanzhou University, No. 222 South Tianshui Road, Lanzhou, 730000, Gansu Province, P.R. China
| | - Abdullah M Al-Enizi
- Department of Chemistry, College of Science, King Saud University, Riyadh, 11451, Saudi Arabia
| | - Ayman Nafady
- Department of Chemistry, College of Science, King Saud University, Riyadh, 11451, Saudi Arabia
| | - Zhiyong Tang
- National Center for Nanoscience and Nanotechnology, No.11 ZhongGuanCun BeiYiTiao, 100190, Beijing, P.R. China
| | - Shengqian Ma
- Department of Chemistry, University of North Texas, 1508 W Mulberry St, Denton, TX 76201, USA
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6
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Maji S, Sarkar P, Das A, Pati SK, Mandal SK. Benzimidazolylidene-Stabilized Borenium Ion for Catalytic Hydrogenation of N-Heterocycles. Inorg Chem 2022; 61:14282-14287. [PMID: 36047676 DOI: 10.1021/acs.inorgchem.2c01841] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Herein, we report the synthesis of a benzimidazolylidene-stabilized borane adduct and its borenium ion. This borenium ion was used as a metal-free catalyst for hydrogenating various substituted quinoline N-heterocycles under ambient conditions. Furthermore, this method was utilized to synthesize two drug molecules: galipinine and angustureine. A detailed DFT study was performed to understand this metal-free catalytic hydrogenation.
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Affiliation(s)
- Subir Maji
- Department of Chemical Sciences, Indian Institute of Science Education and Research (IISER) Kolkata, Mohanpur 741246, India
| | - Pallavi Sarkar
- Theoretical Sciences Unit, Jawaharlal Nehru Centre For Advanced Scientific Research, Bangalore 560064, India
| | - Arpan Das
- Department of Chemical Sciences, Indian Institute of Science Education and Research (IISER) Kolkata, Mohanpur 741246, India
| | - Swapan K Pati
- Theoretical Sciences Unit, Jawaharlal Nehru Centre For Advanced Scientific Research, Bangalore 560064, India
| | - Swadhin K Mandal
- Department of Chemical Sciences, Indian Institute of Science Education and Research (IISER) Kolkata, Mohanpur 741246, India
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7
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Han C, Meng W, Feng X, Du H. Asymmetric Intramolecular Hydroalkoxylation of 2‐Vinylbenzyl Alcohols with Chiral Boro‐Phosphates. Angew Chem Int Ed Engl 2022; 61:e202200100. [DOI: 10.1002/anie.202200100] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/14/2022] [Indexed: 11/10/2022]
Affiliation(s)
- Caifang Han
- Beijing National Laboratory for Molecular Sciences CAS Key Laboratory of Molecular Recognition and Function Institute of Chemistry Chinese Academy of Sciences Beijing 100190 China
- University of Chinese Academy of Sciences Beijing 100049 China
| | - Wei Meng
- Beijing National Laboratory for Molecular Sciences CAS Key Laboratory of Molecular Recognition and Function Institute of Chemistry Chinese Academy of Sciences Beijing 100190 China
- University of Chinese Academy of Sciences Beijing 100049 China
| | - Xiangqing Feng
- Beijing National Laboratory for Molecular Sciences CAS Key Laboratory of Molecular Recognition and Function Institute of Chemistry Chinese Academy of Sciences Beijing 100190 China
- University of Chinese Academy of Sciences Beijing 100049 China
| | - Haifeng Du
- Beijing National Laboratory for Molecular Sciences CAS Key Laboratory of Molecular Recognition and Function Institute of Chemistry Chinese Academy of Sciences Beijing 100190 China
- University of Chinese Academy of Sciences Beijing 100049 China
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8
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Yu K, Feng X, Du H. Asymmetric hydrogenation of TIPS-protected oximes with chiral boranes. Org Biomol Chem 2022; 20:3708-3711. [PMID: 35439808 DOI: 10.1039/d2ob00602b] [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
An enantioselective metal-free hydrogenation of TIPS-protected oximes has been successfully realized for the first time by using chiral borane catalysts derived from chiral dienes and Piers' borane. A variety of hydroxylamine derivatives were afforded in 84-99% yields with 33-68% ees.
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Affiliation(s)
- Kuai Yu
- Beijing National Laboratory for Molecular Sciences, CAS Key Laboratory of Molecular Recognition and Function, Institute of Chemistry, Chinese Academy of Sciences, Beijing 100190, China. .,College of Chemistry and Material Sciences, Hebei Normal University, Shijiazhuang, Hebei 050024, P. R. China
| | - Xiangqing Feng
- Beijing National Laboratory for Molecular Sciences, CAS Key Laboratory of Molecular Recognition and Function, Institute of Chemistry, Chinese Academy of Sciences, Beijing 100190, China. .,University of Chinese Academy of Sciences, Beijing 100049, China
| | - Haifeng Du
- Beijing National Laboratory for Molecular Sciences, CAS Key Laboratory of Molecular Recognition and Function, Institute of Chemistry, Chinese Academy of Sciences, Beijing 100190, China. .,University of Chinese Academy of Sciences, Beijing 100049, China
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9
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Asymmetric Intramolecular Hydroalkoxylation of 2‐Vinylbenzyl Alcohols with Chiral Boro‐Phosphates. Angew Chem Int Ed Engl 2022. [DOI: 10.1002/ange.202200100] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
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10
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Abstract
Borenium ions are strong Lewis acids because of the positive charge on boron. While their high reactivity had long restricted their role in organic synthesis to stoichiometric reagents, in the past ten years the introduction of suitable supporting ligands, such as N-heterocyclic carbenes, has enabled them to function as competent catalysts for various organic transformations involving the activation of strong covalent bonds, such as H-H, Si-H, B-H, C-H and C-C bonds. This review provides an overview of the recent advances in borenium-catalysed reactions with emphasis on catalyst synthesis, methodology development and mechanistic insight.
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Affiliation(s)
- Xinyue Tan
- Shanghai Key Laboratory of Molecular Catalysis and Innovative Materials, Department of Chemistry, Fudan University, Songhu Road 2005, Shanghai, 200438, P. R. China.
| | - Huadong Wang
- Shanghai Key Laboratory of Molecular Catalysis and Innovative Materials, Department of Chemistry, Fudan University, Songhu Road 2005, Shanghai, 200438, P. R. China.
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11
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Dai Y, Meng W, Feng X, Du H. Chiral FLP-catalyzed asymmetric hydrogenation of 3-fluorinated chromones. Chem Commun (Camb) 2022; 58:1558-1560. [PMID: 35014638 DOI: 10.1039/d1cc06964k] [Citation(s) in RCA: 13] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/17/2023]
Abstract
The asymmetric hydrogenation of fluorinated olefins is an efficient pathway towards the synthesis of chiral fluorine-containing compounds. This paper described metal-free asymmetric hydrogenation of 3-fluorinated chromones with the use of readily available achiral borane and chiral oxazoline as an FLP catalyst for the first time. A variety of optically active 3-fluorochroman-4-ones were obtained in high yields with up to 88% ee.
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Affiliation(s)
- Yun Dai
- Beijing National Laboratory for Molecular Sciences, CAS Key Laboratory of Molecular Recognition and Function, Institute of Chemistry, Chinese Academy of Sciences, Beijing 100190, China. .,University of Chinese Academy of Sciences, Beijing 100049, China
| | - Wei Meng
- Beijing National Laboratory for Molecular Sciences, CAS Key Laboratory of Molecular Recognition and Function, Institute of Chemistry, Chinese Academy of Sciences, Beijing 100190, China. .,University of Chinese Academy of Sciences, Beijing 100049, China
| | - Xiangqing Feng
- Beijing National Laboratory for Molecular Sciences, CAS Key Laboratory of Molecular Recognition and Function, Institute of Chemistry, Chinese Academy of Sciences, Beijing 100190, China. .,University of Chinese Academy of Sciences, Beijing 100049, China
| | - Haifeng Du
- Beijing National Laboratory for Molecular Sciences, CAS Key Laboratory of Molecular Recognition and Function, Institute of Chemistry, Chinese Academy of Sciences, Beijing 100190, China. .,University of Chinese Academy of Sciences, Beijing 100049, China
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12
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Maity R, Sarkar B. Chemistry of Compounds Based on 1,2,3-Triazolylidene-Type Mesoionic Carbenes. JACS AU 2022; 2:22-57. [PMID: 35098220 PMCID: PMC8790748 DOI: 10.1021/jacsau.1c00338] [Citation(s) in RCA: 20] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/01/2021] [Indexed: 05/04/2023]
Abstract
Mesoionic carbenes (MICs) of the 1,2,3-triazolylidene type have established themselves as a popular class of compounds over the past decade. Primary reasons for this popularity are their modular synthesis and their strong donor properties. While such MICs have mostly been used in combination with transition metals, the past few years have also seen their utility together with main group elements. In this paper, we present an overview of the recent developments on this class of compounds that include, among others, (i) cationic and anionic MIC ligands, (ii) the donor/acceptor properties of these ligands with a focus on the several methods that are known for estimating such donor/acceptor properties, (iii) a detailed overview of 3d metal complexes and main group compounds with these MIC ligands, (iv) results on the redox and photophysical properties of compounds based on MIC ligands, and (v) an overview on electrocatalysis, redox-switchable catalysis, and small-molecule activation to highlight the applications of compounds based on MIC ligands in contemporary chemistry. By discussing several aspects from the synthetic, spectroscopic, and application point of view of these classes of compounds, we highlight the state of the art of compounds containing MICs and present a perspective for future research in this field.
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Affiliation(s)
- Ramananda Maity
- Dr.
R. Maity Department of Chemistry, University
of Calcutta, 92, A. P.
C. Road, Kolkata 700009, India
| | - Biprajit Sarkar
- Prof.
Dr. B. Sarkar Lehrstuhl für Anorganische Koordinationschemie,
Institut für Anorganische Chemie, Universität Stuttgart, Pfaffenwaldring 55, D-70569 Stuttgart, Germany
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13
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Hollister KK, Molino A, Breiner G, Walley JE, Wentz KE, Conley AM, Dickie DA, Wilson DJD, Gilliard RJ. Air-Stable Thermoluminescent Carbodicarbene-Borafluorenium Ions. J Am Chem Soc 2022; 144:590-598. [PMID: 35016509 DOI: 10.1021/jacs.1c11861] [Citation(s) in RCA: 17] [Impact Index Per Article: 8.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/04/2023]
Abstract
Borenium ions, originally synthesized as fundamentally important laboratory curiosities, have attracted significant attention due to their applications in catalysis and frustrated Lewis pair chemistry. However, investigations of the materials properties of these types of compounds are exceptionally rare. Herein, we report the synthesis, molecular structures, and optical properties of a new class of air-stable borenium ions, stabilized by the strongly donating carbodicarbene (CDC) ligand (2, 3, 6). Notably, CDC-borafluorenium ions exhibit thermoluminescence in solution, a result of a twisted intramolecular charge transfer process. The temperature responsiveness, which is observable by the naked eye, is assessed over a 20 to -60 °C range. Significantly, compound 2 emits white light at lower temperatures. In the solid state, these borocations exhibit increased quantum yields due to aggregation-induced emission. CDC-borafluorenium ions with two different counteranions (Br-, BPh4-) were investigated to evaluate the effect of anion size on the solution and solid-state optical properties. In addition, CDCs containing both symmetrical and unsymmetrical N-heterocycles (bis(1-isopropyl-3-methylbenzimidazol-2-ylidene)methane and bis(1,3-dimethyl-1,3-dihydro-2H-benzo[d]imidazol-2-ylidene)methane) were tested to understand the implications of free rotation about the CDC ligand carbon-carbon bonds. The experimental work is complemented by a comprehensive theoretical analysis of the excited-state dynamics.
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Affiliation(s)
- Kimberly K Hollister
- Department of Chemistry, University of Virginia, Charlottesville, Virginia 22904, United States
| | - Andrew Molino
- Department of Chemistry and Physics, La Trobe Institute for Molecular Science, La Trobe University, Melbourne, 3086, Victoria, Australia
| | - Grace Breiner
- Department of Chemistry, University of Virginia, Charlottesville, Virginia 22904, United States
| | - Jacob E Walley
- Department of Chemistry, University of Virginia, Charlottesville, Virginia 22904, United States
| | - Kelsie E Wentz
- Department of Chemistry, University of Virginia, Charlottesville, Virginia 22904, United States
| | - Ashley M Conley
- Department of Chemical Engineering, University of Virginia, Charlottesville, Virginia 22904, United States
| | - Diane A Dickie
- Department of Chemistry, University of Virginia, Charlottesville, Virginia 22904, United States
| | - David J D Wilson
- Department of Chemistry and Physics, La Trobe Institute for Molecular Science, La Trobe University, Melbourne, 3086, Victoria, Australia
| | - Robert J Gilliard
- Department of Chemistry, University of Virginia, Charlottesville, Virginia 22904, United States
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14
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Li X, Song Q. Chiral Borane-Catalyzed Enantioselective Reactions. CHINESE J ORG CHEM 2022. [DOI: 10.6023/cjoc202208018] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
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15
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Mukhopadhyay S, Boobalan R, Chein RJ. Oxathiaborolium-catalyzed enantioselective [2 + 2] cycloadditions. Org Biomol Chem 2022; 20:8405-8409. [DOI: 10.1039/d2ob01779b] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Abstract
The one-pot-prepared oxathiaborolium pentachlorostannate is an excellent Lewis acid and is successfully used to catalyze the [2 + 2] cycloadditions of N-substituted maleimides and silyl enol ethers with excellent enantioselectivities.
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Affiliation(s)
| | | | - Rong-Jie Chein
- Institute of Chemistry, Academia Sinica, Nankang, Taipei 11529, Taiwan
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16
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Chen J, Gao B, Feng X, Meng W, Du H. Relay Catalysis by Achiral Borane and Chiral Phosphoric Acid in the Metal-Free Asymmetric Hydrogenation of Chromones. Org Lett 2021; 23:8565-8569. [PMID: 34669401 DOI: 10.1021/acs.orglett.1c03286] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
A strategy of relay catalysis by achiral borane and chiral phosphoric acid was successfully developed for the asymmetric hydrogenation of chromones, giving the desired products in high yields with up to 95% ee. Achiral borane and chiral phosphoric acid are highly compatible in this reaction. The achiral borane acts as a Lewis acid for the first-step hydrogenation, and the chiral phosphoric acid acts as an effective chiral proton shuttle to control the enantioselectivity.
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Affiliation(s)
- Jingjing Chen
- Beijing National Laboratory for Molecular Sciences, CAS Key Laboratory of Molecular Recognition and Function, Institute for Chemistry, Chinese Academy of Sciences, Beijing 100190, China.,University of Chinese Academy of Sciences, Beijing 100049, China
| | - Bochao Gao
- Beijing National Laboratory for Molecular Sciences, CAS Key Laboratory of Molecular Recognition and Function, Institute for Chemistry, Chinese Academy of Sciences, Beijing 100190, China.,University of Chinese Academy of Sciences, Beijing 100049, China
| | - Xiangqing Feng
- Beijing National Laboratory for Molecular Sciences, CAS Key Laboratory of Molecular Recognition and Function, Institute for Chemistry, Chinese Academy of Sciences, Beijing 100190, China.,University of Chinese Academy of Sciences, Beijing 100049, China
| | - Wei Meng
- Beijing National Laboratory for Molecular Sciences, CAS Key Laboratory of Molecular Recognition and Function, Institute for Chemistry, Chinese Academy of Sciences, Beijing 100190, China.,University of Chinese Academy of Sciences, Beijing 100049, China
| | - Haifeng Du
- Beijing National Laboratory for Molecular Sciences, CAS Key Laboratory of Molecular Recognition and Function, Institute for Chemistry, Chinese Academy of Sciences, Beijing 100190, China.,University of Chinese Academy of Sciences, Beijing 100049, China
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17
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Shih DN, Boobalan R, Liu YH, Chein RJ, Chiu CW. [B-Cl-B] + Cations: Chloroborane Masked Chiral Borenium Ions. Inorg Chem 2021; 60:16266-16272. [PMID: 34672549 DOI: 10.1021/acs.inorgchem.1c02073] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
A tricoordinate borenium ion has received considerable attention in recent years for its applications in Lewis acid catalysis. Over the years, asymmetric catalysis mediated by a chiral borenium ion has also been developed. To stabilize the electron-deficient boron atom, a series of chloroborane masked borenium ions featuring the symmetrical [B-Cl-B]+ linkage are prepared and utilized as the catalyst for the enantioselective Diels-Alder cycloaddition of cyclopentadiene and 2,2,2-trifluoroethyl acrylate. The presence of a Cp* ligand is critical in realizing the cyclic diboron compounds, and the stability of the resulting [B-Cl-B]+ cation is dependent on the steric bulkiness of the oxazolidinone moiety. The stereoselectivity of the Diels-Alder cycloaddition is controlled by the substituents of the chiral oxazolidinone ligand and could be further improved via the coordination of SnCl4 at the bridging chloride of the [B-Cl-B]+ cation.
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Affiliation(s)
- Ding-Nan Shih
- Department of Chemistry, National Taiwan University, Taipei 10617, Taiwan
| | | | - Yi-Hung Liu
- Department of Chemistry, National Taiwan University, Taipei 10617, Taiwan
| | - Rong-Jie Chein
- Institute of Chemistry, Academia Sinica, Taipei 11529, Taiwan
| | - Ching-Wen Chiu
- Department of Chemistry, National Taiwan University, Taipei 10617, Taiwan
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18
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Pokhodylo NT, Pitkovych KY. Boron-substituted 1,2,3-triazoles (microreview). Chem Heterocycl Compd (N Y) 2021. [DOI: 10.1007/s10593-021-02976-6] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
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19
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Boobalan R, Chein RJ. Oxathiaborolium-Catalyzed Enantioselective [4 + 2] Cycloaddition and Its Application in Lewis Acid Coordinated and Chiral Lewis Acid Catalyzed [4 + 2] Cycloaddition. Org Lett 2021; 23:6760-6764. [PMID: 34410733 DOI: 10.1021/acs.orglett.1c02345] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
The nascency of second-generation sulfur-stabilized borenium cations by halophilic Lewis acid SnCl4 leads to highly active chiral Lewis acids that are very effective catalysts for [4 + 2] cycloaddition. Oxathiaborolium pentachlorostannate (5-10 mol %) successfully catalyzed cycloaddition of various dienes and dienophiles to afford cycloadducts with excellent enantioselectivity (20 examples, up to 99% ee). This super Lewis acid also exhibited good enantioselectivity for the first Lewis acid coordinated and chiral Lewis acid catalyzed [4 + 2] cycloaddition to α,β-unsaturated mixed ester amide.
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Affiliation(s)
| | - Rong-Jie Chein
- Institute of Chemistry, Academia Sinica, Nankang, Taipei 11529, Taiwan
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20
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Clarke JJ, Maekawa Y, Nambo M, Crudden CM. Borenium-Catalyzed Reduction of Pyridines through the Combined Action of Hydrogen and Hydrosilane. Org Lett 2021; 23:6617-6621. [PMID: 34383490 DOI: 10.1021/acs.orglett.1c01892] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Mesoionic carbene-stabilized borenium ions efficiently reduce substituted pyridines to piperidines in the presence of a hydrosilane and a hydrogen atmosphere. Control experiments and deuterium labeling studies demonstrate reversible hydrosilylation of the pyridine, enabling full reduction of the N-heterocycle under milder conditions. The silane is a critical reaction component to prevent adduct formation between the piperidine product and the borenium catalyst.
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Affiliation(s)
- Joshua J Clarke
- Department of Chemistry, Queen's University, 90 Bader Lane, Kingston, Ontario, Canada K7L 3N6
| | - Yuuki Maekawa
- Department of Chemistry, Queen's University, 90 Bader Lane, Kingston, Ontario, Canada K7L 3N6.,Institute of Transformative Bio-Molecules (WPI-ITbM), Nagoya University, Furo, Chikusa, Nagoya 464-8602, Japan
| | - Masakazu Nambo
- Institute of Transformative Bio-Molecules (WPI-ITbM), Nagoya University, Furo, Chikusa, Nagoya 464-8602, Japan
| | - Cathleen M Crudden
- Department of Chemistry, Queen's University, 90 Bader Lane, Kingston, Ontario, Canada K7L 3N6.,Institute of Transformative Bio-Molecules (WPI-ITbM), Nagoya University, Furo, Chikusa, Nagoya 464-8602, Japan
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21
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Mono‐ and Di‐Mesoionic Carbene‐Boranes: Synthesis, Structures and Utility as Reducing Agents. Eur J Inorg Chem 2021. [DOI: 10.1002/ejic.202100273] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
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22
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Stöhr F, Kulhanek N, Becker J, Göttlich R, Schindler S. Reactivity of Copper(I) Complexes Containing Ligands Derived from (1
S
,3
R
)‐Camphoric Acid with Dioxygen. Eur J Inorg Chem 2021. [DOI: 10.1002/ejic.202100187] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022]
Affiliation(s)
- Fabian Stöhr
- Institute for Inorganic and Analytical Chemistry Justus-Liebig-University Gießen Heinrich-Buff-Ring 17 35392 Gießen Germany
- Institute for Organic Chemistry Justus-Liebig-University Gießen Heinrich-Buff-Ring 17 35392 Gießen Germany
| | - Niclas Kulhanek
- Institute for Organic Chemistry Justus-Liebig-University Gießen Heinrich-Buff-Ring 17 35392 Gießen Germany
| | - Jonathan Becker
- Institute for Inorganic and Analytical Chemistry Justus-Liebig-University Gießen Heinrich-Buff-Ring 17 35392 Gießen Germany
| | - Richard Göttlich
- Institute for Organic Chemistry Justus-Liebig-University Gießen Heinrich-Buff-Ring 17 35392 Gießen Germany
| | - Siegfried Schindler
- Institute for Inorganic and Analytical Chemistry Justus-Liebig-University Gießen Heinrich-Buff-Ring 17 35392 Gießen Germany
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23
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Kilic A, Beyazsakal L, Işık M, Türkeş C, Necip A, Takım K, Beydemir Ş. Mannich reaction derived novel boron complexes with amine-bis(phenolate) ligands: Synthesis, spectroscopy and in vitro/in silico biological studies. J Organomet Chem 2020. [DOI: 10.1016/j.jorganchem.2020.121542] [Citation(s) in RCA: 27] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
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24
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Kilic A, Beyazsakal L, Findik BT, Incebay H. Synthesis and electrochemical investigation of chiral amine bis(phenolate)-boron complexes: In vitro antibacterial activity screening of boron compounds. Inorganica Chim Acta 2020. [DOI: 10.1016/j.ica.2020.119777] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/16/2023]
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25
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Affiliation(s)
- Nan Li
- Beijing National Laboratory for Molecular Sciences (BNLMS), Key Laboratory of Bioorganic Chemistry and Molecular Engineering of Ministry of Education, College of Chemistry, Peking University Beijing 100871 China
- Henan Key Laboratory of Function‐Oriented Porous Materials, College of Chemistry and Chemical Engineering, Luoyang Normal University, Luoyang Henan 471934 China
| | - Wen‐Xiong Zhang
- Beijing National Laboratory for Molecular Sciences (BNLMS), Key Laboratory of Bioorganic Chemistry and Molecular Engineering of Ministry of Education, College of Chemistry, Peking University Beijing 100871 China
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26
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Sapsford JS, Csókás D, Scott DJ, Turnell-Ritson RC, Piascik AD, Pápai I, Ashley AE. Establishing the Role of Triflate Anions in H 2 Activation by a Cationic Triorganotin(IV) Lewis Acid. ACS Catal 2020; 10:7573-7583. [PMID: 32905389 PMCID: PMC7469243 DOI: 10.1021/acscatal.0c02023] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/06/2020] [Revised: 06/05/2020] [Indexed: 12/13/2022]
Abstract
![]()
Cationic
Lewis acids (LAs) are gaining interest as targets for
frustrated Lewis pair (FLP)-mediated catalysis. Unlike neutral boranes,
which are the most prevalent LAs for FLP hydrogenations, the Lewis
acidity of cations can be tuned through modulation of the counteranion;
however, detailed studies on such anion effects are currently lacking
in the literature. Herein, we present experimental and computational
studies which probe the mechanism of H2 activation using iPr3SnOTf (1-OTf) in conjunction
with a coordinating (quinuclidine; qui) and noncoordinating (2,4,6-collidine;
col) base and compare its reactivity with {iPr3Sn·base}{Al[OC(CF3)3]4} (base = qui/col) systems which lack a coordinating anion to investigate
the active species responsible for H2 activation and hence
resolve any mechanistic roles for OTf– in the iPr3SnOTf-mediated pathway.
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Affiliation(s)
- Joshua S. Sapsford
- Molecular Sciences Research Hub, Imperial College, White City Campus, 80 Wood Lane, London W12 0BZ, U.K
| | - Dániel Csókás
- Institute of Organic Chemistry, Research Center for Natural Sciences, Magyar tudósok körútja 2, Budapest H-1117, Hungary
| | - Daniel J. Scott
- Institute of Inorganic Chemistry, University of Regensburg, Universitätsstraße 31, Regensburg 93051, Germany
| | - Roland C. Turnell-Ritson
- Molecular Sciences Research Hub, Imperial College, White City Campus, 80 Wood Lane, London W12 0BZ, U.K
| | - Adam D. Piascik
- Molecular Sciences Research Hub, Imperial College, White City Campus, 80 Wood Lane, London W12 0BZ, U.K
| | - Imre Pápai
- Institute of Organic Chemistry, Research Center for Natural Sciences, Magyar tudósok körútja 2, Budapest H-1117, Hungary
| | - Andrew E. Ashley
- Molecular Sciences Research Hub, Imperial College, White City Campus, 80 Wood Lane, London W12 0BZ, U.K
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27
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Kilic A, Balci TE, Arslan N, Aydemir M, Durap F, Okumuş V, Tekin R. Synthesis of
cis
‐1,2‐diol‐type chiral ligands and their dioxaborinane derivatives: Application for the asymmetric transfer hydrogenation of various ketones and biological evaluation. Appl Organomet Chem 2020. [DOI: 10.1002/aoc.5835] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022]
Affiliation(s)
- Ahmet Kilic
- Art and Science Faculty, Chemistry Department Harran University Sanliurfa 63190 Turkey
| | - Tuğba Ersayan Balci
- Art and Science Faculty, Chemistry Department Harran University Sanliurfa 63190 Turkey
| | - Nevin Arslan
- Department of Field Crops, Faculty of Agriculture Şırnak University Şırnak 73000 Turkey
| | - Murat Aydemir
- Department of Chemistry, Science Faculty Dicle University Diyarbakir 21280 Turkey
| | - Feyyaz Durap
- Department of Chemistry, Science Faculty Dicle University Diyarbakir 21280 Turkey
| | - Veysi Okumuş
- Department of Biology, Faculty of Science and Art University of Siirt Siirt 56100 Turkey
| | - Recep Tekin
- Department of Infectious Diseases and Clinical Microbiology DicleUniversity Faculty of Medicine Diyarbakir 21280 Turkey
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28
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Sharma G, Newman PD, Melen R, Platts JA. Computational design of an intramolecular frustrated lewis pair catalyst for enantioselective hydrogenation. JOURNAL OF THEORETICAL & COMPUTATIONAL CHEMISTRY 2020. [DOI: 10.1142/s0219633620500091] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
Abstract
We report DFT calculations on potential intramolecular, enantioselective hydrogenation catalysts based around borenium-carbenes based on a camphor scaffold. Using the M06-2X meta-hybrid functional, we find frustrated Lewis pair (FLP) behavior with suitably chosen linkers that prevent association of Lewis bases with the borenium center. These intramolecular FLPs are predicted to be able to heterolytically dissociate H2. Barriers to dissociation and the endo/exoergic nature of the reaction can be tuned by the nature of the base and substituent on B. The reactivity of the hydrogenated FLP catalyst with olefin and carbonyl substrates is then explored: we predict concerted reactions for all substrates considered with relatively low barriers and large exoergic character. Hydrogenation of both faces of a prochiral substrate is also examined, indicating a small but significant variation in reaction barrier in favor of the Si-face, ascribed to stronger interactions with the aromatic [Formula: see text]-system in the TS compared to the Re-face.
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Affiliation(s)
- Gitanjali Sharma
- School of Chemistry, Cardiff University, Park Place, Cardiff CF10 3AT, UK
| | - Paul D. Newman
- School of Chemistry, Cardiff University, Park Place, Cardiff CF10 3AT, UK
| | - Rebecca Melen
- School of Chemistry, Cardiff University, Park Place, Cardiff CF10 3AT, UK
| | - James A. Platts
- School of Chemistry, Cardiff University, Park Place, Cardiff CF10 3AT, UK
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29
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Affiliation(s)
- Wei Meng
- Beijing National Laboratory for Molecular Sciences, CAS Key Laboratory of Molecular Recognition and Function, Institute of Chemistry, Chinese Academy of Sciences Beijing 100049 China
- University of Chinese Academy of Sciences Beijing 100049 China
| | - Xiangqing Feng
- Beijing National Laboratory for Molecular Sciences, CAS Key Laboratory of Molecular Recognition and Function, Institute of Chemistry, Chinese Academy of Sciences Beijing 100049 China
- University of Chinese Academy of Sciences Beijing 100049 China
| | - Haifeng Du
- Beijing National Laboratory for Molecular Sciences, CAS Key Laboratory of Molecular Recognition and Function, Institute of Chemistry, Chinese Academy of Sciences Beijing 100049 China
- University of Chinese Academy of Sciences Beijing 100049 China
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30
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Raghavendra B, Bakthavachalam K, Das T, Roisnel T, Sen SS, Vanka K, Ghosh S. Transmetallation vs adduct: Diverse reactivity of N,O-ketiminato germylene with [Cp*MCl2]2 (M = Rh or Ir; Cp* = η5-C5Me5) and MCl5 (M = Nb and Ta). J Organomet Chem 2020. [DOI: 10.1016/j.jorganchem.2020.121142] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
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31
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Helmbrecht SL, Schlüter J, Blazejak M, Hintermann L. Axially Chiral 1,1'‐Binaphthyl‐2‐Carboxylic Acid (BINA‐Cox) as Ligands for Titanium‐Catalyzed Asymmetric Hydroalkoxylation. European J Org Chem 2020. [DOI: 10.1002/ejoc.201901895] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Affiliation(s)
- Sebastian L. Helmbrecht
- Department Chemie Technische Universität München Lichtenbergstr. 4 85748 Garching bei München Germany
- TUM Catalysis Research Center Technische Universität München Ernst‐Otto‐Fischer‐Str. 1 85748 Garching bei München Germany
| | - Johannes Schlüter
- Department Chemie Technische Universität München Lichtenbergstr. 4 85748 Garching bei München Germany
- TUM Catalysis Research Center Technische Universität München Ernst‐Otto‐Fischer‐Str. 1 85748 Garching bei München Germany
| | - Max Blazejak
- Department Chemie Technische Universität München Lichtenbergstr. 4 85748 Garching bei München Germany
- TUM Catalysis Research Center Technische Universität München Ernst‐Otto‐Fischer‐Str. 1 85748 Garching bei München Germany
| | - Lukas Hintermann
- Department Chemie Technische Universität München Lichtenbergstr. 4 85748 Garching bei München Germany
- TUM Catalysis Research Center Technische Universität München Ernst‐Otto‐Fischer‐Str. 1 85748 Garching bei München Germany
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32
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Gao B, Feng X, Meng W, Du H. Asymmetric Hydrogenation of Ketones and Enones with Chiral Lewis Base Derived Frustrated Lewis Pairs. Angew Chem Int Ed Engl 2020; 59:4498-4504. [PMID: 31863715 DOI: 10.1002/anie.201914568] [Citation(s) in RCA: 47] [Impact Index Per Article: 11.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/14/2019] [Indexed: 01/13/2023]
Abstract
The concept of frustrated Lewis pairs (FLPs) has been widely applied in various research areas, and metal-free hydrogenation undoubtedly belongs to the most significant and successful ones. In the past decade, great efforts have been devoted to the synthesis of chiral boron Lewis acids. In a sharp contrast, chiral Lewis base derived FLPs have rarely been disclosed for the asymmetric hydrogenation. In this work, a novel type of chiral FLP was developed by simple combination of chiral oxazoline Lewis bases with achiral boron Lewis acids, thus providing a promising new direction for the development of chiral FLPs in the future. These chiral FLPs proved to be highly effective for the asymmetric hydrogenation of ketones, enones, and chromones, giving the corresponding products in high yields with up to 95 % ee. Mechanistic studies suggest that the hydrogen transfer to simple ketones likely proceeds in a concerted manner.
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Affiliation(s)
- Bochao Gao
- Beijing National Laboratory for Molecular Sciences, CAS Key Laboratory of Molecular Recognition and Function, CAS Research/Education Center for Excellence in Molecular Sciences, Institute of Chemistry, Chinese Academy of Sciences, Beijing, 100190, China.,School of Chemical Sciences, University of Chinese Academy of Sciences, Beijing, 100049, China
| | - Xiangqing Feng
- Beijing National Laboratory for Molecular Sciences, CAS Key Laboratory of Molecular Recognition and Function, CAS Research/Education Center for Excellence in Molecular Sciences, Institute of Chemistry, Chinese Academy of Sciences, Beijing, 100190, China.,School of Chemical Sciences, University of Chinese Academy of Sciences, Beijing, 100049, China
| | - Wei Meng
- Beijing National Laboratory for Molecular Sciences, CAS Key Laboratory of Molecular Recognition and Function, CAS Research/Education Center for Excellence in Molecular Sciences, Institute of Chemistry, Chinese Academy of Sciences, Beijing, 100190, China.,School of Chemical Sciences, University of Chinese Academy of Sciences, Beijing, 100049, China
| | - Haifeng Du
- Beijing National Laboratory for Molecular Sciences, CAS Key Laboratory of Molecular Recognition and Function, CAS Research/Education Center for Excellence in Molecular Sciences, Institute of Chemistry, Chinese Academy of Sciences, Beijing, 100190, China.,School of Chemical Sciences, University of Chinese Academy of Sciences, Beijing, 100049, China
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33
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Gao B, Feng X, Meng W, Du H. Asymmetric Hydrogenation of Ketones and Enones with Chiral Lewis Base Derived Frustrated Lewis Pairs. Angew Chem Int Ed Engl 2020. [DOI: 10.1002/ange.201914568] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/30/2023]
Affiliation(s)
- Bochao Gao
- Beijing National Laboratory for Molecular SciencesCAS Key Laboratory of Molecular Recognition and FunctionCAS Research/Education Center for Excellence in Molecular SciencesInstitute of ChemistryChinese Academy of Sciences Beijing 100190 China
- School of Chemical SciencesUniversity of Chinese Academy of Sciences Beijing 100049 China
| | - Xiangqing Feng
- Beijing National Laboratory for Molecular SciencesCAS Key Laboratory of Molecular Recognition and FunctionCAS Research/Education Center for Excellence in Molecular SciencesInstitute of ChemistryChinese Academy of Sciences Beijing 100190 China
- School of Chemical SciencesUniversity of Chinese Academy of Sciences Beijing 100049 China
| | - Wei Meng
- Beijing National Laboratory for Molecular SciencesCAS Key Laboratory of Molecular Recognition and FunctionCAS Research/Education Center for Excellence in Molecular SciencesInstitute of ChemistryChinese Academy of Sciences Beijing 100190 China
- School of Chemical SciencesUniversity of Chinese Academy of Sciences Beijing 100049 China
| | - Haifeng Du
- Beijing National Laboratory for Molecular SciencesCAS Key Laboratory of Molecular Recognition and FunctionCAS Research/Education Center for Excellence in Molecular SciencesInstitute of ChemistryChinese Academy of Sciences Beijing 100190 China
- School of Chemical SciencesUniversity of Chinese Academy of Sciences Beijing 100049 China
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34
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Huchenski BSN, Christopherson CJ, Robertson KN, Speed AWH. Bis-aminocyclopropenylidene carbene borane catalyzed imine hydrogenation. Org Biomol Chem 2019; 17:6158-6164. [PMID: 31183491 DOI: 10.1039/c9ob01053j] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Certain borenium cations supported by carbenes can function as hydrogenation catalysts for imines. While many carbenes have been explored, variation of the other groups on boron has been less common. We have investigated several carbene-borane adducts in an attempt to understand the ability of a bis-amino cyclopropenylidene (BAC) carbene dicyclohexylborane adduct to hydrogenate relatively sterically unhindered benzyl imines. As an additional variant, a BAC carbene adduct of diphenylborane was prepared. A convenient preparation of diphenylboron fluoride via a potassium fluoroborinate salt was employed in this chemistry. Reaction of diphenylboron fluoride with a BAC carbene afforded a modest yield of a carbene-fluoroborane adduct. Reaction between the fluoroborinate salt and a lithium tetrafluoroborate adduct of the carbene provided the adduct in much improved yield and cleanliness, and the product was structurally characterized. The fluoroborate could be converted to a boron hydride through fluoride-hydride exchange with dimethylchlorosilane. The boron hydride adduct was also structurally characterized. Unlike the BAC carbene dicyclohexylborane adduct, the BAC carbene diphenylborane adduct showed essentially no activity in hydrogenation of imines or enamines.
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Affiliation(s)
- Blake S N Huchenski
- Department of Chemistry, Dalhousie University, 6274 Coburg Road, Halifax, NS B3H 4R2, Canada.
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35
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Manar KK, Porwal VK, Kamte RS, Adhikari M, Thakur SK, Bawari D, Choudhury AR, Singh S. Reactions of a BICAAC with hydroboranes: propensity for Lewis adduct formation and carbene insertion into the B-H bond. Dalton Trans 2019; 48:17472-17478. [PMID: 31714564 DOI: 10.1039/c9dt03382c] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
The reactivity of a bicyclic (alkyl)(amino)carbene (BICAAC) towards different boranes has been examined in the present work. The reactions with boranes BX3·SMe2 (X = H, Cl, Br), BF3·OEt2 and BCl3 yield Lewis adducts [BICAAC·BH3] (1), [BICAAC·BHCl2] (2), [BICAAC·BH2Cl] (3), [BICAAC·BF3] (4), [BICAAC·BCl3] (5) and [BICAAC·BBr3] (6) respectively, whereas more hydridic boranes, 9-borabicyclo[3.3.1]nonane (9-BBN) and catecholborane (HBcat), enable the insertion of the carbene carbon into the B-H bond to form [BICAAC(H)-(9-BBN)] (7) and [BICAAC(H)-Bcat] (8). These complexes are the first examples of BICAAC-boron compounds and have been characterized using IR, multinuclear NMR spectroscopy, HRMS spectrometry and single crystal X-ray diffraction. Computational analyses were also performed to gain insight into the mechanism of B-H bond activation and adduct formation. Furthermore, the reactions of the BICAAC with boranes have been compared with the known reactions of CAACs and NHCs.
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Affiliation(s)
- Krishna K Manar
- Department of Chemical Sciences, Indian Institute of Science Education and Research Mohali, Knowledge City, Sector 81, SAS Nagar, Mohali 140306, Punjab, India.
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36
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Virant M, Košmrlj J. Arylation of Click Triazoles with Diaryliodonium Salts. J Org Chem 2019; 84:14030-14044. [DOI: 10.1021/acs.joc.9b02197] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022]
Affiliation(s)
- Miha Virant
- Faculty of Chemistry and Chemical Technology, University of Ljubljana, Večna pot 113, SI 1000 Ljubljana, Slovenia
| | - Janez Košmrlj
- Faculty of Chemistry and Chemical Technology, University of Ljubljana, Večna pot 113, SI 1000 Ljubljana, Slovenia
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37
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Aupic C, Abdou Mohamed A, Figliola C, Nava P, Tuccio B, Chouraqui G, Parrain JL, Chuzel O. Highly diastereoselective preparation of chiral NHC-boranes stereogenic at the boron atom. Chem Sci 2019; 10:6524-6530. [PMID: 31341605 PMCID: PMC6611065 DOI: 10.1039/c9sc01454c] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/25/2019] [Accepted: 05/23/2019] [Indexed: 11/21/2022] Open
Abstract
Stereogenic main group elements are clearly generating interest in the enantioselective catalysis field. Surprisingly, while chiral organoboron reagents are very useful in stereoselective transformations, few scaffolds stereogenic at boron and configurationally stable have been reported to date. Herein, we describe an original library of chiral NHC-boranes, stereogenic at the boron atom, that has been prepared in only a few steps and in good yields (up to 93%). Key steps involve a chlorination/arylation sequence in the presence of simple Grignard reagents from bicyclic NHC-boranes. The high and unprecedented diastereoselectivity observed during the second step (up to 99 : 1 dr) has been rationalized through a plausible SRN1 mechanism thanks to EPR observations and DFT calculations.
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Affiliation(s)
- Clara Aupic
- Aix Marseille Univ , CNRS , Centrale Marseille, iSm2 , Marseille , France .
| | - Amel Abdou Mohamed
- Aix Marseille Univ , CNRS , Centrale Marseille, iSm2 , Marseille , France .
| | - Carlotta Figliola
- Aix Marseille Univ , CNRS , Centrale Marseille, iSm2 , Marseille , France .
| | - Paola Nava
- Aix Marseille Univ , CNRS , Centrale Marseille, iSm2 , Marseille , France .
| | | | - Gaëlle Chouraqui
- Aix Marseille Univ , CNRS , Centrale Marseille, iSm2 , Marseille , France .
| | - Jean-Luc Parrain
- Aix Marseille Univ , CNRS , Centrale Marseille, iSm2 , Marseille , France .
| | - Olivier Chuzel
- Aix Marseille Univ , CNRS , Centrale Marseille, iSm2 , Marseille , France .
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38
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Hoshimoto Y, Ogoshi S. Triarylborane-Catalyzed Reductive N-Alkylation of Amines: A Perspective. ACS Catal 2019. [DOI: 10.1021/acscatal.9b01356] [Citation(s) in RCA: 33] [Impact Index Per Article: 6.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Affiliation(s)
- Yoichi Hoshimoto
- Department of Applied Chemistry, Faculty of Engineering, Osaka University, Suita, Osaka 565-0871, Japan
| | - Sensuke Ogoshi
- Department of Applied Chemistry, Faculty of Engineering, Osaka University, Suita, Osaka 565-0871, Japan
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39
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Bamford KL, Qu ZW, Stephan DW. Activation of H2 and Et3SiH by the Borinium Cation [Mes2B]+: Avenues to Cations [MesB(μ-H)2(μ-Mes)BMes]+ and [H2B(μ-H)(μ-Mes)B(μ-Mes)(μ-H)BH2]+. J Am Chem Soc 2019; 141:6180-6184. [DOI: 10.1021/jacs.9b02510] [Citation(s) in RCA: 27] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Karlee L. Bamford
- Department of Chemistry, University of Toronto, 80 St. George Street, Toronto, Ontario M5S 3H6, Canada
| | - Zheng-Wang Qu
- Mulliken Center for Theoretical Chemistry, University of Bonn, Beringstr. 4, D-53115 Bonn, Germany
| | - Douglas W. Stephan
- Department of Chemistry, University of Toronto, 80 St. George Street, Toronto, Ontario M5S 3H6, Canada
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40
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Möricke J, Rehwinkel F, Danelzik T, Daniliuc CG, Wibbeling B, Kehr G, Erker G. Developing carbon Lewis base/boron Lewis acid frustrated Lewis pair chemistry derived from conjugated dienamines. Tetrahedron 2019. [DOI: 10.1016/j.tet.2018.11.068] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022]
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41
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Sampford KR, Carden JL, Kidner EB, Berry A, Cavell KJ, Murphy DM, Kariuki BM, Newman PD. Twisting the arm: structural constraints in bicyclic expanded-ring N-heterocyclic carbenes. Dalton Trans 2019; 48:1850-1858. [PMID: 30652174 DOI: 10.1039/c8dt04462g] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/24/2023]
Abstract
A series of diaryl, mono-aryl/alkyl and dialkyl mono- and bicyclic expanded-ring N-heterocyclic carbenes (ER-NHCs) have been prepared and their complexation to Au(i) investigated through the structural analysis of fifteen Au(NHC)X and/or [Au(NHC)2]X complexes. The substituted diaryl 7-NHCs are the most sterically encumbered with large buried volume (%VB) values of 40-50% with the less flexible six-membered analogues having %VB values at least 5% smaller. Although the bicyclic systems containing fused 6- and 7-membered rings (6,7-NHCs) are constrained with relatively acute NCN bond angles, they have the largest %VB values of the dialkyl derivatives reported here, a feature related to the fixed conformation of the heterocyclic rings and the compressional effect of a pre-set methyl substituent.
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Affiliation(s)
| | - Jamie L Carden
- School of Chemistry, Cardiff University, Cardiff, CF10 3AT, UK
| | - Edward B Kidner
- School of Chemistry, Cardiff University, Cardiff, CF10 3AT, UK
| | - Abigail Berry
- School of Chemistry, Cardiff University, Cardiff, CF10 3AT, UK
| | | | - Damien M Murphy
- School of Chemistry, Cardiff University, Cardiff, CF10 3AT, UK
| | | | - Paul D Newman
- School of Chemistry, Cardiff University, Cardiff, CF10 3AT, UK and Cardiff Catalysis Institute, School of Chemistry, Cardiff University, Cardiff, CF10 3AT, UK.
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42
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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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43
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Lam J, Szkop KM, Mosaferi E, Stephan DW. FLP catalysis: main group hydrogenations of organic unsaturated substrates. Chem Soc Rev 2019; 48:3592-3612. [PMID: 30178796 DOI: 10.1039/c8cs00277k] [Citation(s) in RCA: 234] [Impact Index Per Article: 46.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
Abstract
This article is focused on recent developments in main group mediated hydrogenation chemistry and catalysis using "frustrated Lewis pairs" (FLPs). The broading range of substrates and catalyst systems is reviewed and the advances in catalytic reductions and the development of stereoselective, asymmetric reductions made since 2012 is considered.
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Affiliation(s)
- Jolie Lam
- Department of Chemistry, University of Toronto, 80 St. George St., Toronto, Ontario M5S3H6, Canada.
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44
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Nava P, Toure M, Abdou Mohamed A, Parrain JL, Chuzel O. Investigation of the rhodium-catalyzed hydroboration of NHC-boranes: the role of alkene coordination and the origin of enantioselectivity. Dalton Trans 2019; 48:17605-17611. [DOI: 10.1039/c9dt03660a] [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 mechanism of the intramolecular enantioselective rhodium(i)-catalyzed hydroboration of NHC-boranes is investigated by experiments and calculations, using Density Functional Theory and Random Phase Approximation methods.
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Affiliation(s)
- Paola Nava
- Aix Marseille University
- CNRS
- Marseille
- France
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45
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Mercea DM, Howlett MG, Piascik AD, Scott DJ, Steven A, Ashley AE, Fuchter MJ. Enantioselective reduction of N-alkyl ketimines with frustrated Lewis pair catalysis using chiral borenium ions. Chem Commun (Camb) 2019; 55:7077-7080. [DOI: 10.1039/c9cc02900a] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/09/2023]
Abstract
Effective enantioselective reduction of ketimines has been demonstrated by ‘frustrated’ Lewis pair catalysis using an IBiox-stabilised borenium cation.
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Affiliation(s)
- Dan M. Mercea
- Department of Chemistry
- Imperial College London
- Molecular Sciences Research Hub
- London
- UK
| | - Michael G. Howlett
- Department of Chemistry
- Imperial College London
- Molecular Sciences Research Hub
- London
- UK
| | - Adam D. Piascik
- Department of Chemistry
- Imperial College London
- Molecular Sciences Research Hub
- London
- UK
| | - Daniel J. Scott
- Department of Chemistry
- Imperial College London
- Molecular Sciences Research Hub
- London
- UK
| | | | - Andrew E. Ashley
- Department of Chemistry
- Imperial College London
- Molecular Sciences Research Hub
- London
- UK
| | - Matthew J. Fuchter
- Department of Chemistry
- Imperial College London
- Molecular Sciences Research Hub
- London
- UK
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46
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Bartholome TA, Bluer KR, Martin CD. Successive carbene insertion into 9-phenyl-9-borafluorene. Dalton Trans 2019; 48:6319-6322. [PMID: 30942222 DOI: 10.1039/c9dt01032g] [Citation(s) in RCA: 20] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/10/2023]
Abstract
The reactions of 9-phenyl-9-borafluorene with trimethylsilyldiazomethane in a 1 : 1 and 1 : 2 stoichiometry furnished the corresponding BC5 and BC6 heterocycles via the formal insertion of one and two carbene units.
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Affiliation(s)
- Tyler A Bartholome
- Baylor University, Department of Chemistry and Biochemistry, One Bear Place #97348, Waco, TX 76798, USA.
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47
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Lam J, Sampaolesi S, LaFortune JHW, Coe JW, Stephan DW. Design considerations for chiral frustrated Lewis pairs: B/N FLPs derived from 3,5-bicyclic aryl piperidines. Dalton Trans 2018; 48:133-141. [PMID: 30484790 DOI: 10.1039/c8dt04070b] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Herein, 3,5-bicyclic aryl piperidines are derivatized to generate chiral B/N FLPs. Initially, the twofold symmetric amine C6H2F2(C5H8NiPr) 1 was converted in a series of synthetic steps to the styrene-derivative C6HF2(C5H8NiPr)(CH[double bond, length as m-dash]CH2) 4. Efforts to hydroborate the vinyl fragment proved challenging as a result of the strongly basic nitrogen, although the species C6HF2(C5H8N(H)iPr)(CH2CH2B(OH)(C6F5)2) 5 was crystallographically characterized. Modification of the system was achieved by conversion of the amine C6H2F2(C5H8NH) 6 to C6HF2(C5H8NPh)(CH[double bond, length as m-dash]CH2) 9. Hydroboration of 9 with 9-BBN or HB(C6F5)2 gave C6HF2(C5H8NPh)(CH2CH2BBN) 10 or C6HF2(C5H8NPh)(CH2CH2B(C6F5)2) 11, respectively. The latter species was derivatized by complexation of PPh3 to give C6HF2(C5H8NPh)(CH2CH2B(C6F5)2)(PPh3) 12. The Lewis acidities of 10 and 11 were assessed by the Gutman-Beckett test and by computations of the FIA and GEI. While 10 did not effect HD scrambling or hydrogenation of N-phenylbenzylimine, 11 was effective in HD scrambling. Despite this, no reduction of N-t-butylbenzylimine or N-phenylbenzylimine was achieved. These data demonstrate that 10 lacks the threshold combination of Lewis acidity and basicity to activate H2, while 11 lacks the steric demands about boron to preclude classical Lewis acid-base bond formation with imine substrates.
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Affiliation(s)
- Jolie Lam
- Department of Chemistry, University of Toronto, 80 St George St, Toronto, M5S3H6, Canada.
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48
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Guisado-Barrios G, Soleilhavoup M, Bertrand G. 1 H-1,2,3-Triazol-5-ylidenes: Readily Available Mesoionic Carbenes. Acc Chem Res 2018; 51:3236-3244. [PMID: 30417642 DOI: 10.1021/acs.accounts.8b00480] [Citation(s) in RCA: 133] [Impact Index Per Article: 22.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
Abstract
Classical carbenes are usually described as neutral compounds featuring a divalent carbon with only six electrons in their valence shell. It was only in 1988 that our group prepared the first isolable example, in which the carbene center was stabilized by a push-pull effect, using a phosphino and a silyl substituent. In the last 30 years, a myriad of acyclic and cyclic push-pull and push-push carbenes, bearing different heteroatom substituents, have been isolated. Among them, the so-called N-heterocyclic carbenes (NHCs), which include cyclic (alkyl)(amino)carbenes (CAACs), are arguably the most popular. They have found a vast number of applications ranging from catalysis to material science, and even in medicine. In this Account, we focus on the synthesis, structure, electronic properties, coordination, and applications of a different class of stable cyclic carbenes, namely, 1 H-1,2,3-triazol-5-ylidenes. In contrast with NHCs and CAACs, these compounds have no reasonable canonical resonance forms that can be drawn showing a carbene without additional charges. According to the IUPAC, they belong to the family of mesoionic compounds and thus they are named mesoionic carbenes (MICs). In 2010, we prepared the first stable 1,2,3-triazol-5-ylidene, via a CuAAC reaction, followed by alkylation of the resulting 1,2,3-triazole, and deprotonation. Later, we synthesized more robust N3-arylated counterparts from 1,3-diarylated-1 H-1,2,3-triazolium salts. Both synthetic routes can be carried out in multigram scales, making these MICS readily available. Importantly, MICs do not dimerize which contrasts with NHCs that can give the corresponding Wanzlick-type olefin. This property leads to relaxed steric requirements for their isolation; even C-unsubstituted MICs can be stored for months in the solid state at room temperature. The practicality and easily scalable syntheses of MICs allow for the preparation of polycarbenes, such as bis(1,2,3-triazol-5-ylidenes) (i-bitz), the analogues of the well-known 2,2'-bipyridines (bpy). MIC-transition metal complexes are excellent precatalysts for variety of chemical transformations, which include hydrohydrazination of alkynes, olefin metathesis, reductive formylation of amines with carbon dioxide and diphenylsilane, hydrogenation and dehydrogenation of N-heteroarenes in water, cycloisomerization of enynes, asymmetric Suzuki-Miyaura cross-coupling, and water oxidation (WO) reactions. Besides their catalytic applications, MIC-transition metal complexes have found applications in material sciences as exemplified by the preparation of the first iron(III) complex that is luminescent at room temperature. The peculiar properties of mesoionic triazolylidenes, combined with their enhanced stability, position them as excellent candidates to address some current challenges such as access to high-oxidation-state 3d metal complexes, the stabilization of highly reactive main group elements, the stabilization of nanoparticles, the preparation of efficient catalysts and photosensitizers based on earth-abundant transition metals, and the functionalization of self-assembled monolayers (SAMs) on gold.
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Affiliation(s)
- Gregorio Guisado-Barrios
- Institute of Advance Materials (INAM), Universitat Jaume I, Avenida Vicente Sos Baynat s/n, 12071 Castellon, Spain
| | - Michèle Soleilhavoup
- UCSD-CNRS Joint Research Laboratory (UMI 3555), Department of Chemistry and Biochemistry, University of California, San Diego, La Jolla, California 92093-0343, United states
| | - Guy Bertrand
- UCSD-CNRS Joint Research Laboratory (UMI 3555), Department of Chemistry and Biochemistry, University of California, San Diego, La Jolla, California 92093-0343, United states
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49
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Liu X, Liu T, Meng W, Du H. Asymmetric hydrogenation of imines with chiral alkene-derived boron Lewis acids. Org Biomol Chem 2018; 16:8686-8689. [PMID: 30387483 DOI: 10.1039/c8ob02446d] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022]
Abstract
With the aim of developing easily accessible chiral Lewis acids for asymmetric hydrogenation, a variety of binaphthyl-based chiral alkenes were prepared in one step from the corresponding diols. Using the in situ generated chiral boron Lewis acids through the hydroboration of chiral alkenes with Piers' borane, metal-free asymmetric hydrogenations of imines were realized to furnish the desired amine products in high yields with up to 89% ee.
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Affiliation(s)
- Xiaoqin Liu
- Beijing National Laboratory of Molecular Sciences, CAS Key Laboratory of Molecular Recognition and Function, Institute of Chemistry, Chinese Academy of Sciences, Beijing 100190, China.
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50
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Tu X, Zeng N, Li R, Zhao Y, Xie D, Peng Q, Wang X. C
2
‐Symmetric Bicyclic Bisborane Catalysts: Kinetic or Thermodynamic Products of a Reversible Hydroboration of Dienes. Angew Chem Int Ed Engl 2018; 57:15096-15100. [DOI: 10.1002/anie.201808289] [Citation(s) in RCA: 47] [Impact Index Per Article: 7.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/19/2018] [Indexed: 11/09/2022]
Affiliation(s)
- Xian‐Shuang Tu
- State Key Laboratory and Institute of Elemento-Organic ChemistryCollege of Chemistry and Collaborative Innovation Center of Chemical Science and Engineering (Tianjin)Nankai University 94 Weijin Road Tianjin 300071 China
| | - Ning‐Ning Zeng
- State Key Laboratory and Institute of Elemento-Organic ChemistryCollege of Chemistry and Collaborative Innovation Center of Chemical Science and Engineering (Tianjin)Nankai University 94 Weijin Road Tianjin 300071 China
| | - Ru‐Ye Li
- State Key Laboratory and Institute of Elemento-Organic ChemistryCollege of Chemistry and Collaborative Innovation Center of Chemical Science and Engineering (Tianjin)Nankai University 94 Weijin Road Tianjin 300071 China
| | - Yu‐Quan Zhao
- State Key Laboratory and Institute of Elemento-Organic ChemistryCollege of Chemistry and Collaborative Innovation Center of Chemical Science and Engineering (Tianjin)Nankai University 94 Weijin Road Tianjin 300071 China
| | - De‐Zhen Xie
- State Key Laboratory and Institute of Elemento-Organic ChemistryCollege of Chemistry and Collaborative Innovation Center of Chemical Science and Engineering (Tianjin)Nankai University 94 Weijin Road Tianjin 300071 China
| | - Qian Peng
- State Key Laboratory and Institute of Elemento-Organic ChemistryCollege of Chemistry and Collaborative Innovation Center of Chemical Science and Engineering (Tianjin)Nankai University 94 Weijin Road Tianjin 300071 China
| | - Xiao‐Chen Wang
- State Key Laboratory and Institute of Elemento-Organic ChemistryCollege of Chemistry and Collaborative Innovation Center of Chemical Science and Engineering (Tianjin)Nankai University 94 Weijin Road Tianjin 300071 China
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