1
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Stang M, Mycka RJ, Blum SA. Mechanistic Insight from Lewis-Acid-Dependent Selectivity and Reversible Haloboration, as Harnessed for Boron-Based Electrophilic Cyclization Reactions. J Org Chem 2023; 88:15159-15167. [PMID: 37877549 DOI: 10.1021/acs.joc.3c01653] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/26/2023]
Abstract
Different reaction selectivity occurs with the Lewis acids B-chlorocatecholborane (ClBcat), B-bromocatecholborane (BrBcat), and BBr3, favoring either alkyne haloboration, electrophilic cyclization of a tethered nucleophilic sulfur onto the alkyne, or group transfer of the nucleophile. This reaction selectivity also depends on the chain length of the tethered nucleophile, revealing a subtle interplay of relative kinetics and thermodynamics. In all cases, BBr3 reacts readily with alkynes to form haloborated products; however, this process is reversible, and this reversibility can be harnessed to ultimately access regio- and stereodefined cyclic sulfonium zwitterions via the slower but thermodynamically favored electrophilic cyclization pathway. Reversibility was noted by following the reaction by NMR spectroscopy, and by characterizing the kinetic and thermodynamic products by a combination of 2D NMR spectroscopy and single-crystal X-ray diffraction. The "mixed" reagent bromocatechol borane (BrBcat) displayed reactivity between ClBcat and BBr3, producing bromoboration in some cases and electrophilic cyclization in others. With this enhanced understanding of the reaction dynamics, it becomes possible to use boron Lewis acids in a predictable manner in cases where haloboration is the kinetic product but in which the reversibility of this reaction maintains access to eventual alternative reactivity leading to desired building blocks in organic synthesis.
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Affiliation(s)
- Martin Stang
- Department of Chemistry, University of California, Irvine, California 92697-2025, United States
| | - Robert J Mycka
- Department of Chemistry, University of California, Irvine, California 92697-2025, United States
- Community College of Allegheny County, Pittsburgh, Pennsylvania 15212, United States
| | - Suzanne A Blum
- Department of Chemistry, University of California, Irvine, California 92697-2025, United States
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2
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Phatake RS, Averdunk A, Würtele C, Gellrich U. Piers’ Borane-Catalyzed Dimerization of Arylallenes via Transborylation: A Synthetic and Mechanistic Study. ACS Catal 2022. [DOI: 10.1021/acscatal.2c04605] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Ravindra S. Phatake
- Institut für Organische Chemie, Justus-Liebig-Universität Gießen, Heinrich-Buff-Ring 17, 35392Gießen, Germany
| | - Arthur Averdunk
- Institut für Organische Chemie, Justus-Liebig-Universität Gießen, Heinrich-Buff-Ring 17, 35392Gießen, Germany
| | - Christian Würtele
- Institut für Anorganische und Analytische Chemie, Justus-Liebig-Universität Gießen, Heinrich-Buff-Ring 17, 35392Gießen, Germany
| | - Urs Gellrich
- Institut für Organische Chemie, Justus-Liebig-Universität Gießen, Heinrich-Buff-Ring 17, 35392Gießen, Germany
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3
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Hazra S, Mahato S, Kanti Das K, Panda S. Transition-Metal-Free Heterocyclic Carbon-Boron Bond Formation. Chemistry 2022; 28:e202200556. [PMID: 35438817 DOI: 10.1002/chem.202200556] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/21/2022] [Indexed: 12/16/2022]
Abstract
Heteroaryl boronic acids and esters are extremely important and valuable intermediates because of their wide application in the synthesis of marketed drugs and bioactive compounds. Over the last couple of decades, the construction of highly important heteroaryl carbon-boron bonds has created huge attention. The transition-metal-free protocols are more green, less sensitive to air and moisture, and also economically advantageous over the transition-metal-based protocols. The transition-metal-free C-H borylation of heteroarenes and C-X (X=halogen) borylation of heteroaryl halides represents an excellent approach for their synthesis. Also, various cyclization and alkyne activation protocols have been recently established for their synthesis. The goal of this review article is to summarize the existing literature and the current state of the art for transition-metal-free synthesis of heteroaryl boronic acid and esters.
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Affiliation(s)
- Subrata Hazra
- Department of Chemistry, Indian Institute of Technology Kharagpur, Kharagpur, 721302, India
| | - Somenath Mahato
- Department of Chemistry, Indian Institute of Technology Kharagpur, Kharagpur, 721302, India
| | - Kanak Kanti Das
- Department of Chemistry, Indian Institute of Technology Kharagpur, Kharagpur, 721302, India
| | - Santanu Panda
- Department of Chemistry, Indian Institute of Technology Kharagpur, Kharagpur, 721302, India
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4
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Polyak D, Xu B, Krauss IJ. Homoallylboration of Aldehydes: Stereoselective Synthesis of Allylic-Substituted Alkenes and E-Alkenes. Org Lett 2022; 24:4656-4659. [PMID: 35735242 DOI: 10.1021/acs.orglett.2c01789] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
Cyclopropanated allylboration reagents participate in the homoallylation of aliphatic and aromatic aldehydes, generating substituted alkenes that are difficult to produce via other methods. In this study, we explored the scope and reactivity of homoallylation with cyclopropylcarbinylboronates bearing various aliphatic and aromatic α- and γ-substituents. α-Alkyl substituted boronates afforded E-disubstituted alkenyl secondary alcohols in high enantiomeric ratios, while aryl substituents promoted rearrangement. γ-Alkyl substituents all resulted in diastereoselective homoallylation, while aryl substitution changed the outcome to cyclopropylcarbinylation.
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Affiliation(s)
- Daniel Polyak
- Department of Chemistry, Brandeis University, MS 015, Waltham, Massachusetts 02454-9110, United States
| | - Bokai Xu
- Department of Chemistry, Brandeis University, MS 015, Waltham, Massachusetts 02454-9110, United States
| | - Isaac J Krauss
- Department of Chemistry, Brandeis University, MS 015, Waltham, Massachusetts 02454-9110, United States
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5
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Averdunk A, Hasenbeck M, Müller T, Becker J, Gellrich U. 1,2-Carboboration of Arylallenes by In Situ Generated Alkenylboranes for the Synthesis of 1,4-Dienes. Chemistry 2022; 28:e202200470. [PMID: 35348257 PMCID: PMC9325554 DOI: 10.1002/chem.202200470] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/13/2022] [Indexed: 12/26/2022]
Abstract
We herein report a novel method for the coupling of unactivated alkynes and arylallenes, which relies on an unprecedented and regioselective 1,2-carboboration of the allene by an alkenylborane. The alkenylborane is conveniently prepared in situ by hydroboration of an alkyne with Piers' borane, i. e., HB(C6 F5 )2 . The boryl-substituted 1,4-dienes that are formed by this carboboration are well-suited for a subsequent Suzuki-Miyaura coupling with aryl iodides. This allowed us to develop a three-step, one-pot protocol for the synthesis of aryl-substituted 1,4-dienes. The generality of the reaction was demonstrated by the synthesis of twenty dienes with modular variations of all three reaction partners. The mechanism of the new 1,2-carboboration was investigated using dispersion corrected double-hybrid DFT computations that allowed us to rationalize the chemo- and regioselectivity of this key step.
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Affiliation(s)
- Arthur Averdunk
- Institut für Organische ChemieJustus-Liebig-Universität GießenHeinrich-Buff-Ring 1735392GießenGermany
| | - Max Hasenbeck
- Institut für Organische ChemieJustus-Liebig-Universität GießenHeinrich-Buff-Ring 1735392GießenGermany
| | - Tizian Müller
- Institut für Organische ChemieJustus-Liebig-Universität GießenHeinrich-Buff-Ring 1735392GießenGermany
| | - Jonathan Becker
- Institut für Anorganische und Analytische ChemieJustus-Liebig-Universität GießenHeinrich-Buff-Ring 1735392GießenGermany
| | - Urs Gellrich
- Institut für Organische ChemieJustus-Liebig-Universität GießenHeinrich-Buff-Ring 1735392GießenGermany
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6
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Hasenbeck M, Müller T, Averdunk A, Becker J, Gellrich U. Piers' Borane-Induced Tetramerization of Arylacetylenes. Chemistry 2022; 28:e202104254. [PMID: 34882876 PMCID: PMC9303334 DOI: 10.1002/chem.202104254] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/29/2021] [Indexed: 12/22/2022]
Abstract
We herein report that the reaction of Piers' borane, i. e. HB(C6 F5 )2 , with an excess of arylacetylenes at room temperature leads to tetramerization of the acetylene and the diastereoselective formation of boryl-substituted tetra-aryl-tetrahydropentalenes. The reaction mechanism was investigated by isotope labeling experiments and DFT computations. These investigations indicate that a series of 1,2-carboboration reactions form an octatetraene that undergoes an electrocyclization. Two skeletal rearrangements then presumably lead to the formation of the tetrahydropentalene core. Overall, this intricate and unprecedented transformation comprises five carbon-carbon bond formations in a single reaction.
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Affiliation(s)
- Max Hasenbeck
- Institut für Organische ChemieJustus-Liebig-Universität GießenHeinrich-Buff-Ring 1735392GießenGermany
| | - Tizian Müller
- Institut für Organische ChemieJustus-Liebig-Universität GießenHeinrich-Buff-Ring 1735392GießenGermany
| | - Arthur Averdunk
- Institut für Organische ChemieJustus-Liebig-Universität GießenHeinrich-Buff-Ring 1735392GießenGermany
| | - Jonathan Becker
- Institut für Anorganische und Analytische ChemieJustus-Liebig-Universität GießenHeinrich-Buff-Ring 1735392GießenGermany
| | - Urs Gellrich
- Institut für Organische ChemieJustus-Liebig-Universität GießenHeinrich-Buff-Ring 1735392GießenGermany
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7
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Shibuya M, Matsuda M, Yamamoto Y. 1,2-Carbopentafluorophenylation of Alkynes: The Metallomimetic Pull-Push Reactivity of Tris(pentafluorophenyl)borane. Chemistry 2021; 27:8822-8831. [PMID: 33860597 DOI: 10.1002/chem.202101090] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/25/2021] [Indexed: 12/26/2022]
Abstract
We report the novel single-step 1,2-dicarbofunctionalization of an arylacetylene with an allylsilane and tris(pentafluorophenyl)borane [B(C6 F5 )3 ] involving C-C bond formation with C-H bond scission at the β-position to the silicon atom of an allylsilane and B→C migration of a C6 F5 group. The 1,2-carbopentafluorophenylation occurs smoothly without the requirement for a catalyst or heating. Mechanistic studies suggest that the metallomimetic "pull-push" reactivity of B(C6 F5 )3 imparts consecutive electrophilic and nucleophilic characteristics to the benzylic carbon of the arylacetylene. Subsequent photochemical 6π-electrocyclization affords tetrafluoronaphthalenes, which are important in the pharmaceutical and materials sciences. Owing to the unique reactivity of B(C6 F5 )3 , the 1,2-carbopentafluorophenylation using 2-substituted furan proceeded with ring opening, and the reaction using silyl enolates formed a C-C bond with C-O bond scission at the silyloxy-substituted carbon.
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Affiliation(s)
- Masatoshi Shibuya
- Department of Basic Medicinal Sciences, Graduate School of Pharmaceutical Sciences, Nagoya University, Chikusa, Nagoya, 464-8601, Japan
| | - Miki Matsuda
- Department of Basic Medicinal Sciences, Graduate School of Pharmaceutical Sciences, Nagoya University, Chikusa, Nagoya, 464-8601, Japan
| | - Yoshihiko Yamamoto
- Department of Basic Medicinal Sciences, Graduate School of Pharmaceutical Sciences, Nagoya University, Chikusa, Nagoya, 464-8601, Japan
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8
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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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9
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Abstract
In contrast to previously reported borylative heterocyclization methods, a reaction here proceeds without air-free techniques to access synthetically useful borylated thiophenes, benzothiophenes, and isocoumarins. A comparison of stability/decomposition rates in air of several catecholboronic ester (Bcat) compounds derived from different heterocycle cores showed a strong dependence on the heterocycle structure. Lessons learned from this comparison were then harnessed for the development of borylative heterocyclization reactions under ambient-atmosphere conditions and with wet solvent. In contrast to literature reports suggesting general moisture sensitivity, a subset of Bcat products resulting from this technique were chromatography-stable and directly isolable, obviating the requirement for an extra synthetic transformation into more stable boron species, such as pinacolboronic esters (Bpin), for isolation. The isolated Bcat products were amenable to various downstream functionalization reactions, including reactions that were not accessible with their better-known Bpin counterparts, showing the complementarity of Bcat reaction partners and expanding their known chemistry. These results suggest the value of conceptual revisitation of substitution and solvent influence on stability and isolability of organo-Bcat compound classes and lay the groundwork for development of additional practical borylative methods in air.
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Affiliation(s)
- Chao Gao
- Department of Chemistry, University of California, Irvine, California 92697-2025, United States
| | - Shuichi Nakao
- Department of Chemistry, University of California, Irvine, California 92697-2025, United States
| | - Suzanne A Blum
- Department of Chemistry, University of California, Irvine, California 92697-2025, United States
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10
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Yang CH, Han M, Li W, Zhu N, Sun Z, Wang J, Yang Z, Li YM. Direct Intramolecular Aminoboration of Allenes. Org Lett 2020; 22:5090-5093. [DOI: 10.1021/acs.orglett.0c01685] [Citation(s) in RCA: 14] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Affiliation(s)
- Chun-Hua Yang
- Henan Key Laboratory of New Optoelectronic Functional Materials, College of Chemistry and Chemical Engineering, Anyang Normal University, 436 Xian’ge Road, Anyang 455000, People’s Republic of China
| | - Meng Han
- Henan Key Laboratory of New Optoelectronic Functional Materials, College of Chemistry and Chemical Engineering, Anyang Normal University, 436 Xian’ge Road, Anyang 455000, People’s Republic of China
| | - Wenyan Li
- Henan Key Laboratory of New Optoelectronic Functional Materials, College of Chemistry and Chemical Engineering, Anyang Normal University, 436 Xian’ge Road, Anyang 455000, People’s Republic of China
| | - Ningning Zhu
- Henan Key Laboratory of New Optoelectronic Functional Materials, College of Chemistry and Chemical Engineering, Anyang Normal University, 436 Xian’ge Road, Anyang 455000, People’s Republic of China
| | - Zhenzhen Sun
- Henan Key Laboratory of New Optoelectronic Functional Materials, College of Chemistry and Chemical Engineering, Anyang Normal University, 436 Xian’ge Road, Anyang 455000, People’s Republic of China
| | - Junjie Wang
- Henan Key Laboratory of New Optoelectronic Functional Materials, College of Chemistry and Chemical Engineering, Anyang Normal University, 436 Xian’ge Road, Anyang 455000, People’s Republic of China
| | - Zhantao Yang
- Henan Key Laboratory of New Optoelectronic Functional Materials, College of Chemistry and Chemical Engineering, Anyang Normal University, 436 Xian’ge Road, Anyang 455000, People’s Republic of China
| | - Yue-Ming Li
- State Key Laboratory of Medicinal Chemical Biology, College of Pharmacy and Tianjin Key Laboratory of Molecular Drug Research, Nankai University, 38 Tongyan Road, Tianjin 300353, People’s Republic of China
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11
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Bismuto A, Nichol GS, Duarte F, Cowley MJ, Thomas SP. Characterization of the Zwitterionic Intermediate in 1,1-Carboboration of Alkynes. Angew Chem Int Ed Engl 2020; 59:12731-12735. [PMID: 32343867 DOI: 10.1002/anie.202003468] [Citation(s) in RCA: 17] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/06/2020] [Indexed: 11/12/2022]
Abstract
The reaction of a Lewis acidic borane with an alkyne is a key step in a diverse range of main group transformations. Alkyne 1,1-carboboration, the Wrackmeyer reaction, is an archetypal transformation of this kind. 1,1-Carboboration has been proposed to proceed through a zwitterionic intermediate. We report the isolation and spectroscopic, structural and computational characterization of the zwitterionic intermediates generated by reaction of B(C6 F5 )3 with alkynes. The stepwise reactivity of the zwitterion provides new mechanistic insight for 1,1-carboboration and wider B(C6 F5 )3 catalysis. Making use of intramolecular stabilization by a ferrocene substituent, we have characterized the zwitterionic intermediate in the solid state and diverted reactivity towards alkyne cyclotrimerization.
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Affiliation(s)
- Alessandro Bismuto
- EaStCHEM, School of Chemistry, University of Edinburgh, Joseph Black Building, David Brewster Road, Edinburgh, EH9 3FJ, UK
| | - Gary S Nichol
- EaStCHEM, School of Chemistry, University of Edinburgh, Joseph Black Building, David Brewster Road, Edinburgh, EH9 3FJ, UK
| | - Fernanda Duarte
- Chemistry Research Laboratory, University of Oxford, 12 Mansfield Road, Oxford, OX1 3TA, UK
| | - Michael J Cowley
- EaStCHEM, School of Chemistry, University of Edinburgh, Joseph Black Building, David Brewster Road, Edinburgh, EH9 3FJ, UK
| | - Stephen P Thomas
- EaStCHEM, School of Chemistry, University of Edinburgh, Joseph Black Building, David Brewster Road, Edinburgh, EH9 3FJ, UK
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12
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Bismuto A, Nichol GS, Duarte F, Cowley MJ, Thomas SP. Characterization of the Zwitterionic Intermediate in 1,1‐Carboboration of Alkynes. Angew Chem Int Ed Engl 2020. [DOI: 10.1002/ange.202003468] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Affiliation(s)
- Alessandro Bismuto
- EaStCHEM School of Chemistry University of Edinburgh Joseph Black Building David Brewster Road Edinburgh EH9 3FJ UK
| | - Gary S. Nichol
- EaStCHEM School of Chemistry University of Edinburgh Joseph Black Building David Brewster Road Edinburgh EH9 3FJ UK
| | - Fernanda Duarte
- Chemistry Research Laboratory University of Oxford 12 Mansfield Road Oxford OX1 3TA UK
| | - Michael J. Cowley
- EaStCHEM School of Chemistry University of Edinburgh Joseph Black Building David Brewster Road Edinburgh EH9 3FJ UK
| | - Stephen P. Thomas
- EaStCHEM School of Chemistry University of Edinburgh Joseph Black Building David Brewster Road Edinburgh EH9 3FJ UK
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13
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Zhang Y, Chen Y, Zhang Z, Liu S, Shen X. Synthesis of Stereodefined Trisubstituted Alkenyl Silanes Enabled by Borane Catalysis and Nickel Catalysis. Org Lett 2020; 22:970-975. [PMID: 31977233 DOI: 10.1021/acs.orglett.9b04505] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
Regioselective and stereoselective synthesis of trisubstituted alkenyl silanes via hydrosilylation is challenging. Herein, we report the first β-anti-selective addition of silanes to thioalkynes with B(C6F5)3 as the catalyst. The reaction shows broad substrate scope. The products were proven to be useful intermediates to other trisubstituted alkenyl silanes by Ni-catalyzed stereoretentive cross-coupling reactions of the C-S bond. A mechanism study suggests that nucleophilic attack of thioalkyne to an activated silylium intermediate might be the rate-determining step.
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Affiliation(s)
- Yunxiao Zhang
- Institute for Advanced Studies, Engineering Research Center of Organosilicon Compounds & Materials, Ministry of Education , Wuhan University , 299 Bayi Road , Wuhan , Hubei 430072 , China
| | - Yanran Chen
- Institute for Advanced Studies, Engineering Research Center of Organosilicon Compounds & Materials, Ministry of Education , Wuhan University , 299 Bayi Road , Wuhan , Hubei 430072 , China
| | - Zeguo Zhang
- Institute for Advanced Studies, Engineering Research Center of Organosilicon Compounds & Materials, Ministry of Education , Wuhan University , 299 Bayi Road , Wuhan , Hubei 430072 , China
| | - Shanshan Liu
- Institute for Advanced Studies, Engineering Research Center of Organosilicon Compounds & Materials, Ministry of Education , Wuhan University , 299 Bayi Road , Wuhan , Hubei 430072 , China
| | - Xiao Shen
- Institute for Advanced Studies, Engineering Research Center of Organosilicon Compounds & Materials, Ministry of Education , Wuhan University , 299 Bayi Road , Wuhan , Hubei 430072 , China
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14
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15
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Adak T, Schulmeister J, Dietl MC, Rudolph M, Rominger F, Hashmi ASK. Gold-Catalyzed Highly Chemo- and Regioselective C-H Bond Functionalization of Phenols with Haloalkynes. European J Org Chem 2019. [DOI: 10.1002/ejoc.201900653] [Citation(s) in RCA: 20] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Affiliation(s)
- Tapas Adak
- Organisch-Chemisches Institut; Universität Heidelberg; Im Neuenheimer Feld 270 69120 Heidelberg Germany
| | - Jürgen Schulmeister
- Organisch-Chemisches Institut; Universität Heidelberg; Im Neuenheimer Feld 270 69120 Heidelberg Germany
| | - Martin C. Dietl
- Organisch-Chemisches Institut; Universität Heidelberg; Im Neuenheimer Feld 270 69120 Heidelberg Germany
| | - Matthias Rudolph
- Organisch-Chemisches Institut; Universität Heidelberg; Im Neuenheimer Feld 270 69120 Heidelberg Germany
| | - Frank Rominger
- Organisch-Chemisches Institut; Universität Heidelberg; Im Neuenheimer Feld 270 69120 Heidelberg Germany
| | - A. Stephen K. Hashmi
- Organisch-Chemisches Institut; Universität Heidelberg; Im Neuenheimer Feld 270 69120 Heidelberg Germany
- Chemistry Department; Faculty of Science; King Abdulaziz University; 21589 Jeddah Saudi Arabia
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16
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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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17
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Devillard M, Regnier V, Pecaut J, Martin D. Stable dicationic dioxoliums and fate of their dioxolyl radicals. Org Chem Front 2019. [DOI: 10.1039/c9qo00298g] [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
A glimpse into uncharted territory: the synthesis and study of dicationic dioxolium salts allow for assessing the fate of the corresponding elusive dioxolyl radicals.
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Affiliation(s)
| | | | - Jacques Pecaut
- Univ. Grenoble Alpes
- CEA
- CNRS
- INAC-SyMMES
- UMR 5819 38000 Grenoble
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18
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Liu W, Zeng R, Han Y, Wang Y, Tao H, Chen Y, Liu F, Liang Y. Computational and experimental investigation on the BCl3 promoted intramolecular amination of alkenes and alkynes. Org Biomol Chem 2019; 17:2776-2783. [DOI: 10.1039/c9ob00264b] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
Abstract
The BCl3 promoted aminoboration of alkenes and alkynes was investigated both computationally and experimentally, leading to the discovery of a metal-free hydroamination of alkynes.
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Affiliation(s)
- Wei Liu
- State Key Laboratory of Coordination Chemistry
- Jiangsu Key Laboratory of Advanced Organic Materials
- School of Chemistry and Chemical Engineering
- Nanjing University
- Nanjing 210023
| | - Ruxin Zeng
- State Key Laboratory of Coordination Chemistry
- Jiangsu Key Laboratory of Advanced Organic Materials
- School of Chemistry and Chemical Engineering
- Nanjing University
- Nanjing 210023
| | - Yingbin Han
- State Key Laboratory of Coordination Chemistry
- Jiangsu Key Laboratory of Advanced Organic Materials
- School of Chemistry and Chemical Engineering
- Nanjing University
- Nanjing 210023
| | - Yajun Wang
- State Key Laboratory of Coordination Chemistry
- Jiangsu Key Laboratory of Advanced Organic Materials
- School of Chemistry and Chemical Engineering
- Nanjing University
- Nanjing 210023
| | - Huimin Tao
- State Key Laboratory of Coordination Chemistry
- Jiangsu Key Laboratory of Advanced Organic Materials
- School of Chemistry and Chemical Engineering
- Nanjing University
- Nanjing 210023
| | - Yu Chen
- State Key Laboratory of Coordination Chemistry
- Jiangsu Key Laboratory of Advanced Organic Materials
- School of Chemistry and Chemical Engineering
- Nanjing University
- Nanjing 210023
| | - Fang Liu
- College of Sciences
- Nanjing Agricultural University
- Nanjing 210095
- China
| | - Yong Liang
- State Key Laboratory of Coordination Chemistry
- Jiangsu Key Laboratory of Advanced Organic Materials
- School of Chemistry and Chemical Engineering
- Nanjing University
- Nanjing 210023
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19
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Bel Abed H, Blum SA. Transition-Metal-Free Synthesis of Borylated Thiophenes via Formal Thioboration. Org Lett 2018; 20:6673-6677. [DOI: 10.1021/acs.orglett.8b02727] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Affiliation(s)
- Hassen Bel Abed
- Department of Chemistry, University of California—Irvine, Irvine, California 92617-2025, United States
| | - Suzanne A. Blum
- Department of Chemistry, University of California—Irvine, Irvine, California 92617-2025, United States
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20
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Lv J, Zhao B, Liu L, Han Y, Yuan Y, Shi Z. Boron Trichloride‐Mediated Synthesis of Indoles
via
the Aminoboration of Alkynes. Adv Synth Catal 2018. [DOI: 10.1002/adsc.201800509] [Citation(s) in RCA: 20] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023]
Affiliation(s)
- Jiahang Lv
- College of Chemistry and Chemical EngineeringYangzhou University Yangzhou 225002 People's Republic of China
- State Key Laboratory of Coordination Chemistry, School of Chemistry and Chemical EngineeringNanjing University Nanjing 210093 People's Republic of China
| | - Binlin Zhao
- State Key Laboratory of Coordination Chemistry, School of Chemistry and Chemical EngineeringNanjing University Nanjing 210093 People's Republic of China
| | - Li Liu
- Jiangsu Key Laboratory of Advanced Catalytic Materials and TechnologyChangzhou University Changzhou 213164 People's Republic of China
| | - Ying Han
- College of Chemistry and Chemical EngineeringYangzhou University Yangzhou 225002 People's Republic of China
| | - Yu Yuan
- College of Chemistry and Chemical EngineeringYangzhou University Yangzhou 225002 People's Republic of China
| | - Zhuangzhi Shi
- College of Chemistry and Chemical EngineeringYangzhou University Yangzhou 225002 People's Republic of China
- State Key Laboratory of Coordination Chemistry, School of Chemistry and Chemical EngineeringNanjing University Nanjing 210093 People's Republic of China
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21
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Wilkins LC, Soltani Y, Lawson JR, Slater B, Melen RL. Divergent Elementoboration: 1,3-Haloboration versus 1,1-Carboboration of Propargyl Esters. Chemistry 2018; 24:7364-7368. [PMID: 29700863 PMCID: PMC6055811 DOI: 10.1002/chem.201801493] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/23/2018] [Indexed: 01/03/2023]
Abstract
This work showcases the 1,3-haloboration reaction of alkynes in which boron and chlorine add to propargyl systems in a proposed sequential oxazoliumborate formation with subsequent ring-opening and chloride migration. In addition, the functionalization of these propargyl esters with dimethyl groups in the propargylic position leads to stark differences in reactivity whereby a formal 1,1-carboboration prevails to give the 2,2-dichloro-3,4-dihydrodioxaborinine products as an intramolecular chelate. Density functional theory calculations are used to rationalize the distinct carboboration and haloboration pathways. Significantly, this method represents a metal-free route to highly functionalized compounds in a single step to give structurally complex products.
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Affiliation(s)
- Lewis C Wilkins
- School of Chemistry, Cardiff University, Main Building, Park Place, Cardiff, CF10 3AT, Cymru/Wales, UK
| | - Yashar Soltani
- School of Chemistry, Cardiff University, Main Building, Park Place, Cardiff, CF10 3AT, Cymru/Wales, UK
| | - James R Lawson
- School of Chemistry, Cardiff University, Main Building, Park Place, Cardiff, CF10 3AT, Cymru/Wales, UK
| | - Ben Slater
- Department of Chemistry, University College London, 20 Gordon Street, London, WC1H 0AJ, UK
| | - Rebecca L Melen
- School of Chemistry, Cardiff University, Main Building, Park Place, Cardiff, CF10 3AT, Cymru/Wales, UK
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22
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Wang T, Daniliuc CG, Mück-Lichtenfeld C, Kehr G, Erker G. Formation of Reactive π-Conjugated Frustrated N/B Pairs by Borane-Induced Propargyl Amine Rearrangement. J Am Chem Soc 2018; 140:3635-3643. [PMID: 29444567 DOI: 10.1021/jacs.7b11958] [Citation(s) in RCA: 25] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
Abstract
N-Propargyltetramethylpiperidine reacts with a series of trans-alkenyl-B(C6F5)2 compounds to give the substituted alkenyl-bridged frustrated N/B Lewis pairs 5. Their structures and spectroscopic features indicate a pronounced participation of the mesomeric s-trans-iminium/borata-alkene resonance form. The compounds are thought to be formed in a stepwise addition/rearrangement process which is initiated by a trans-1,2-amine/borane FLP addition to the carbon-carbon triple bond to generate a reactive zwitterionic aziridinium/alkenylborate intermediate. Subsequent alkenylborate attack leads to opening of the activated three-membered heterocycle with clean formation of the products 5a-c. Treatment of the propargyl-TMP substrate with B(C6F5)3 gave a stable example of such an aziridinium/borate betaine, which was isolated and amply characterized. The products 5a-c are active N/B FLPs. They split dihydrogen heterolytically under mild conditions to give the respective NH+/BH- products 9a-c. These contain Z-configurated core C═C double bonds, which indicates rotational equilibration around the central C-C bond of 5a-c during this reaction. Structural and chemical features of the 5c system were analyzed by DFT calculations.
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Affiliation(s)
- Tongdao Wang
- Organisch-Chemisches Institut , Westfälische Wilhelms-Universität Münster , Corrensstraße 40 , 48149 Münster , Germany
| | - Constantin G Daniliuc
- Organisch-Chemisches Institut , Westfälische Wilhelms-Universität Münster , Corrensstraße 40 , 48149 Münster , Germany
| | - Christian Mück-Lichtenfeld
- Organisch-Chemisches Institut , Westfälische Wilhelms-Universität Münster , Corrensstraße 40 , 48149 Münster , Germany
| | - Gerald Kehr
- Organisch-Chemisches Institut , Westfälische Wilhelms-Universität Münster , Corrensstraße 40 , 48149 Münster , Germany
| | - Gerhard Erker
- Organisch-Chemisches Institut , Westfälische Wilhelms-Universität Münster , Corrensstraße 40 , 48149 Münster , Germany
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23
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Multinuclear NMR spectroscopy, photophysical, electrochemical and DNA-binding properties of fluorinated 1,8-naphthyridine-based boron heterocycles. J Fluor Chem 2018. [DOI: 10.1016/j.jfluchem.2017.11.006] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023]
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24
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Saptal VB, Juneja G, Bhanage BM. B(C6F5)3: a robust catalyst for the activation of CO2 and dimethylamine borane for the N-formylation reactions. NEW J CHEM 2018. [DOI: 10.1039/c8nj02816h] [Citation(s) in RCA: 23] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
In this work, B(C6F5)3 is utilized as an organocatalyst for the transition-metal-free N-formylation of amines using carbon dioxide (CO2) as a C1 source and dimethylamine borane (Me2NH·BH3) as a green hydrogen transfer source at 80 °C.
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Affiliation(s)
- Vitthal B. Saptal
- Department of Chemistry
- Institute of Chemical Technology (Autonomous)
- Matunga
- Mumbai
- India
| | - Gaurav Juneja
- Department of Chemistry
- Institute of Chemical Technology (Autonomous)
- Matunga
- Mumbai
- India
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25
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Houghton AY, Autrey T. Calorimetric Study of the Activation of Hydrogen by Tris(pentafluorophenyl)borane and Trimesitylphosphine. J Phys Chem A 2017; 121:8785-8790. [DOI: 10.1021/acs.jpca.7b08582] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Adrian Y. Houghton
- Pacific Northwest National Laboratory, 902 Battelle Boulevard, P.O. Box 999, Richland, Washington 99352 United States
| | - Tom Autrey
- Pacific Northwest National Laboratory, 902 Battelle Boulevard, P.O. Box 999, Richland, Washington 99352 United States
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26
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Issaian A, Tu KN, Blum SA. Boron-Heteroatom Addition Reactions via Borylative Heterocyclization: Oxyboration, Aminoboration, and Thioboration. Acc Chem Res 2017; 50:2598-2609. [PMID: 28933550 DOI: 10.1021/acs.accounts.7b00365] [Citation(s) in RCA: 57] [Impact Index Per Article: 8.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/28/2023]
Abstract
Organoboron compounds and heterocycles are powerful building blocks and precursors for organic synthesis, including for drug discovery and agrochemical and material synthesis. The common strategy for the synthesis of borylated heterocycles involves two separate synthetic steps: first, synthesis of the heterocyclic core, and second, borylation of the core through established methods such as transition-metal-catalyzed C-H or C-X activation/borylation or lithiation/borylation. In this Account, we describe our laboratory's development of borylative heterocyclization reactions that access the heterocyclic core and install boron in one synthetic step. These methods provide complementary bond disconnections, regiochemistry, and functional-group compatibility to current methods. We describe our methods with two categories: a direct borylation method that refers to addition reactions starting from a preformed B-element σ bond, which is essential in the mechanistic route to product formation, and a formal borylation method that refers to addition reactions that do not require formation of a B-element bond but instead proceed through carbon-carbon π-bond activation by an electrophilic boron source followed by dealkylation or deacylation. Through electrophilic activation of the alkyne rather than activation of the B-element bond, formal borylation provides a complementary strategy toward neutral organoboron reagents. We first studied direct oxyboration toward the formation of borylated benzofurans, where a preformed boron-oxygen σ bond is added across an alkyne activated by a carbophilic gold catalyst. We describe detailed mechanistic and kinetic studies of this class of reactions. Application of the knowledge gained from these studies aided in the future development of additional direct borylation reactions involving boron-nitrogen and boron-oxygen σ bonds to form borylared indoles and isoxazoles, respectively. Formal addition of boron/oxygen equivalents to effect oxyboration to form borylated lactones from o-alkynyl esters is then described. This class of reactions takes advantage of bifunctional ClBcat as a carbophilic carbon-carbon π-bond activator and eventual dealkylating agent. We describe our motivation in developing this new class of catalyst-free borylation reactions and subsequently applying the formal borylation strategy to the thioboration of o-alkynylthioanisole substrates to form borylated benzothiophenes. We then proceed to describe our investigations into the details of the mechanism of the formal thioboration reaction. These collaborative mechanistic studies included experimental and computational findings that elucidated the rate-determining step and intermediates of the reaction. These studies further compared different boron sources as electrophiles, including those used in other known reactions, providing fundamental knowledge about the capabilities of commercially available boron reagents toward borylative heterocyclization. Our findings provide guiding principles for reaction design and information leading toward the design of a diverse set of boron-heteroatom addition reactions and their formal equivalents that proceed through borylative heterocyclization.
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Affiliation(s)
- Adena Issaian
- Department of Chemistry, University of California, Irvine, California 92697-2025, United States
| | - Kim N. Tu
- Department of Chemistry, University of California, Irvine, California 92697-2025, United States
| | - Suzanne A. Blum
- Department of Chemistry, University of California, Irvine, California 92697-2025, United States
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27
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Wei Y, Liu D, Qing X, Xu L. Mechanistic Insights on a Metal-Free Borylative Cyclization of Alkynes Using BCl3
: A Theoretical Investigation. ASIAN J ORG CHEM 2017. [DOI: 10.1002/ajoc.201700343] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
Affiliation(s)
- Yu Wei
- Department School of Chemistry and Chemical Engineering; Key Laboratory for Green Processing of Chemical Engineering of Xinjiang Bingtuan; Shihezi University; Shihezi 832003 China
| | - Dongwei Liu
- Department School of Chemistry and Chemical Engineering; Key Laboratory for Green Processing of Chemical Engineering of Xinjiang Bingtuan; Shihezi University; Shihezi 832003 China
| | - Xinlin Qing
- Department School of Chemistry and Chemical Engineering; Key Laboratory for Green Processing of Chemical Engineering of Xinjiang Bingtuan; Shihezi University; Shihezi 832003 China
| | - Liang Xu
- Department School of Chemistry and Chemical Engineering; Key Laboratory for Green Processing of Chemical Engineering of Xinjiang Bingtuan; Shihezi University; Shihezi 832003 China
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28
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Abstract
The revelation that combinations of Lewis acids and bases for which dative bonding is impeded can activate dihydrogen led to the concept of "frustrated Lewis pairs" (FLPs). Over the past decade, a range of FLP systems and substrate molecules have precipitated a paradigm change in main-group chemistry and metal-free catalysis. The FLP motif has also found application in a growing body of chemical problems in organic synthesis, transition metal and free radical chemistry, materials, enzymatic models, and surface chemistry. The current state of FLP chemistry is assessed herein, and the outlook for the future considered.
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Affiliation(s)
- Douglas W Stephan
- Department of Chemistry, University of Toronto, 80 St. George Street, Toronto, Ontario M5S3H6, Canada
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29
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Issaian A, Faizi DJ, Bailey JO, Mayer P, Berionni G, Singleton DA, Blum SA. Mechanistic Studies of Formal Thioboration Reactions of Alkynes. J Org Chem 2017; 82:8165-8178. [PMID: 28671461 DOI: 10.1021/acs.joc.7b01500] [Citation(s) in RCA: 21] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/10/2023]
Abstract
Several formal heteroborylative cyclization reactions have been recently reported, but little physical-organic and mechanistic data are known. We now investigate the catalyst-free formal thioboration reaction of alkynes to gain mechanistic insight into B-chlorocatecholborane (ClBcat) in its new role as an alkynophilic Lewis acid in electrophilic cyclization/dealkylation reactions. In kinetic studies, the reaction is second-order globally and first-order with respect to both the 2-alkynylthioanisole substrate and the ClBcat electrophile, with activation parameters of ΔG‡ = 27.1 ± 0.1 kcal mol-1 at 90 °C, ΔH‡ = 13.8 ± 1.0 kcal mol-1, and ΔS‡ = -37 ± 3 cal mol-1 K-1, measured over the range 70-90 °C. Carbon kinetic isotope effects supported a rate-determining AdE3 mechanism wherein alkyne activation by neutral ClBcat is concerted with cyclative attack by nucleophilic sulfur. A Hammett study found a ρ+ of -1.7, suggesting cationic charge buildup during the cyclization and supporting rate-determining concerted cyclization. Studies of the reaction with tris(pentafluorophenyl)borane (B(C6F5)3), an activating agent capable of cyclization but not dealkylation, resulted in the isolation of a postcyclization zwitterionic intermediate. Kinetic studies via UV-vis spectroscopy with this boron reagent found second-order kinetics, supporting the likely relevancy of intermediates in this system to the ClBcat system. Computational studies comparing ClBcat with BCl3 as an activating agent showed why BCl3, in contrast to ClBcat, failed to mediate the complete the cyclization/demethylation reaction sequence by itself. Overall, the results support a mechanism in which the ClBcat reagent serves a bifunctional role by sequentially activating the alkyne, despite being less electrophilic than other known alkyne-activating reagents and then providing chloride for post-rate-determining demethylation/neutralization of the resulting zwitterionic intermediate.
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Affiliation(s)
- Adena Issaian
- Department of Chemistry, University of California , Irvine, California 92617-2025, United States
| | - Darius J Faizi
- Department of Chemistry, University of California , Irvine, California 92617-2025, United States
| | - Johnathan O Bailey
- Department of Chemistry, Texas A&M University , P.O. Box 30012, College Station, Texas 77842, United States
| | - Peter Mayer
- Department of Chemistry, Ludwig Maximilian University of Munich , Munich, 80539, Germany
| | - Guillaume Berionni
- Department of Chemistry, Ludwig Maximilian University of Munich , Munich, 80539, Germany
| | - Daniel A Singleton
- Department of Chemistry, Texas A&M University , P.O. Box 30012, College Station, Texas 77842, United States
| | - Suzanne A Blum
- Department of Chemistry, University of California , Irvine, California 92617-2025, United States
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30
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Jian Z, Kehr G, Daniliuc CG, Wibbeling B, Wiegand T, Siedow M, Eckert H, Bursch M, Grimme S, Erker G. CO-Reduction Chemistry: Reaction of a CO-Derived Formylhydridoborate with Carbon Monoxide, with Carbon Dioxide, and with Dihydrogen. J Am Chem Soc 2017; 139:6474-6483. [PMID: 28407466 DOI: 10.1021/jacs.7b02548] [Citation(s) in RCA: 42] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
Abstract
Treatment of the bulky metallocene hydride Cp*2Zr(H)OMes (Cp* = pentamethylcyclopentadienyl, Mes = mesityl) with Piers' borane [HB(C6F5)2] and carbon monoxide (CO) gave the formylhydridoborate complex [Zr]-O═CH-BH(C6F5)2 ([Zr] = Cp*2Zr-OMes). From the dynamic NMR behavior, its endergonic equilibration with the [Zr]-O-CH2-B(C6F5)2 isomer was deduced, which showed typical reactions of an oxygen/boron frustrated Lewis pair. It was trapped with CO to give an O-[Zr] bonded borata-β-lactone. Trapping with carbon dioxide (CO2) gave the respective O-[Zr] bonded cyclic boratacarbonate product. These reaction pathways were analyzed by density functional theory calculation. The formylhydridoborate complex was further reduced by dihydrogen via two steps; it reacted rapidly with H2 to give Cp*2Zr(OH)OMes and H3C-B(C6F5)2, which then slowly reacted further with H2 to eventually give [Zr]-O(H)-B(H)(C6F5)2 and methane (CH4). Most complexes were characterized by X-ray diffraction.
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Affiliation(s)
| | | | | | | | - Thomas Wiegand
- Laboratorium für Physikalische Chemie, ETH Zürich , Vladimir-Prelog-Weg 1-5/10, 8093 Zürich, Switzerland
| | | | - Hellmut Eckert
- Institute of Physics in Sao Carlos, University of Sao Paulo , CEP 369, Sao Carlos, Sao Paulo 13566-590, Brazil
| | - Markus Bursch
- Mulliken Center for Theoretical Chemistry, Institut für Physikalische und Theoretische Chemie, Rheinische Friedrich-Wilhelms Universität Bonn , Beringstr. 4, 53115 Bonn, Germany
| | - Stefan Grimme
- Mulliken Center for Theoretical Chemistry, Institut für Physikalische und Theoretische Chemie, Rheinische Friedrich-Wilhelms Universität Bonn , Beringstr. 4, 53115 Bonn, Germany
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31
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Fasano V, Radcliffe JE, Ingleson MJ. Mechanistic Insights into the B(C6F5)3-Initiated Aldehyde–Aniline–Alkyne Reaction To Form Substituted Quinolines. Organometallics 2017. [DOI: 10.1021/acs.organomet.7b00174] [Citation(s) in RCA: 23] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Valerio Fasano
- School of Chemistry, University of Manchester, Manchester M13 9PL, United Kingdom
| | - James E. Radcliffe
- School of Chemistry, University of Manchester, Manchester M13 9PL, United Kingdom
| | - Michael J. Ingleson
- School of Chemistry, University of Manchester, Manchester M13 9PL, United Kingdom
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32
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Lawson JR, Melen RL. Tris(pentafluorophenyl)borane and Beyond: Modern Advances in Borylation Chemistry. Inorg Chem 2017; 56:8627-8643. [DOI: 10.1021/acs.inorgchem.6b02911] [Citation(s) in RCA: 153] [Impact Index Per Article: 21.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/25/2023]
Affiliation(s)
- James R. Lawson
- School of Chemistry, Cardiff University, Main Building, Cardiff CF10 3AT, Wales
| | - Rebecca L. Melen
- School of Chemistry, Cardiff University, Main Building, Cardiff CF10 3AT, Wales
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33
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Wang T, Jentgens X, Daniliuc CG, Kehr G, Erker G. Tris(pentafluorophenyl)borane-Catalyzed Reaction of Phosphorus/Boron and Nitrogen/Boron Frustrated Lewis Pair Dihydrogen Activation Products with Alkenes and Alkynes. ChemCatChem 2017. [DOI: 10.1002/cctc.201601229] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
Affiliation(s)
- Tongdao Wang
- Organisch-Chemisches Institut; Westfälische Wilhelms-Universität Münster; Corrensstraße 40 48149 Münster Germany
| | - Xenia Jentgens
- Organisch-Chemisches Institut; Westfälische Wilhelms-Universität Münster; Corrensstraße 40 48149 Münster Germany
| | - Constantin G. Daniliuc
- Organisch-Chemisches Institut; Westfälische Wilhelms-Universität Münster; Corrensstraße 40 48149 Münster Germany
| | - Gerald Kehr
- Organisch-Chemisches Institut; Westfälische Wilhelms-Universität Münster; Corrensstraße 40 48149 Münster Germany
| | - Gerhard Erker
- Organisch-Chemisches Institut; Westfälische Wilhelms-Universität Münster; Corrensstraße 40 48149 Münster Germany
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34
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Yang Z, Yang CH, Chen S, Chen X, Zhang L, Ren H. Catalyst free annulative thioboration of unfunctionalized olefins. Chem Commun (Camb) 2017; 53:12092-12095. [DOI: 10.1039/c7cc06800j] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Abstract
A direct and catalyst-free annulative thioboration of unfunctionalized olefins has been developed.
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Affiliation(s)
- Zhantao Yang
- College of Chemistry and Chemical Engineering
- Anyang Normal University
- Anyang 455000
- P. R. China
- School of Pharmaceutical Sciences
| | - Chun-Hua Yang
- College of Chemistry and Chemical Engineering
- Anyang Normal University
- Anyang 455000
- P. R. China
| | - Shiqi Chen
- College of Chemistry and Chemical Engineering
- Anyang Normal University
- Anyang 455000
- P. R. China
| | - Xixi Chen
- College of Chemistry and Chemical Engineering
- Anyang Normal University
- Anyang 455000
- P. R. China
| | - Litian Zhang
- College of Chemistry and Chemical Engineering
- Anyang Normal University
- Anyang 455000
- P. R. China
| | - Huijun Ren
- College of Chemistry and Chemical Engineering
- Anyang Normal University
- Anyang 455000
- P. R. China
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35
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Tussing S, Ohland M, Wicker G, Flörke U, Paradies J. Borane-catalyzed indole synthesis through intramolecular hydroamination. Dalton Trans 2017; 46:1539-1545. [DOI: 10.1039/c6dt04725d] [Citation(s) in RCA: 35] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022]
Abstract
Catalytic metal-free intramolecular hydroamination for the synthesis of indoles and tetrahydroisoquinolines was achieved.
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Affiliation(s)
- Sebastian Tussing
- Institute of Organic Chemistry
- University of Paderborn
- D-33098 Paderborn
- Germany
| | - Miriam Ohland
- Institute of Organic Chemistry
- University of Paderborn
- D-33098 Paderborn
- Germany
| | - Garrit Wicker
- Institute of Organic Chemistry
- University of Paderborn
- D-33098 Paderborn
- Germany
| | - Ulrich Flörke
- Institute of Inorganic Chemistry
- University of Paderborn
- D-33098 Paderborn
- Germany
| | - Jan Paradies
- Institute of Organic Chemistry
- University of Paderborn
- D-33098 Paderborn
- Germany
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36
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Sato K, Tan TTY, Schäfers F, Hahn FE, Stephan DW. Imidazole-stabilized, electron-deficient boron cations. Dalton Trans 2017; 46:16404-16407. [DOI: 10.1039/c7dt04030j] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Highly Lewis acidic borenium cations were prepared and are shown to activate H2 and effect 1,1-carborations of alkynes.
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Affiliation(s)
- Kaoko Sato
- Institut für Anorganische und Analytische Chemie
- Westfälische Wilhelms-Universität Münster
- D-48149 Münster
- Germany
- Department of chemistry
| | - Tristan Tsai Yuan Tan
- Institut für Anorganische und Analytische Chemie
- Westfälische Wilhelms-Universität Münster
- D-48149 Münster
- Germany
| | - Felix Schäfers
- Institut für Anorganische und Analytische Chemie
- Westfälische Wilhelms-Universität Münster
- D-48149 Münster
- Germany
| | - F. Ekkehardt Hahn
- Institut für Anorganische und Analytische Chemie
- Westfälische Wilhelms-Universität Münster
- D-48149 Münster
- Germany
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37
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Zhuang FD, Han JM, Tang S, Yang JH, Chen QR, Wang JY, Pei J. Efficient Modular Synthesis of Substituted Borazaronaphthalene. Organometallics 2016. [DOI: 10.1021/acs.organomet.6b00811] [Citation(s) in RCA: 28] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Fang-Dong Zhuang
- Beijing National Laboratory
for Molecular Sciences, Key Laboratory of Bioorganic Chemistry and
Molecular Engineering of Ministry of Education, Key Laboratory of
Polymer Chemistry and Physics of Ministry of Education, Center for
Soft Matter Science and Engineering, College of Chemistry and Molecular
Engineering, Peking University, Beijing 100871, People’s Republic of China
| | - Ji-Min Han
- Beijing National Laboratory
for Molecular Sciences, Key Laboratory of Bioorganic Chemistry and
Molecular Engineering of Ministry of Education, Key Laboratory of
Polymer Chemistry and Physics of Ministry of Education, Center for
Soft Matter Science and Engineering, College of Chemistry and Molecular
Engineering, Peking University, Beijing 100871, People’s Republic of China
| | - Sheng Tang
- Beijing National Laboratory
for Molecular Sciences, Key Laboratory of Bioorganic Chemistry and
Molecular Engineering of Ministry of Education, Key Laboratory of
Polymer Chemistry and Physics of Ministry of Education, Center for
Soft Matter Science and Engineering, College of Chemistry and Molecular
Engineering, Peking University, Beijing 100871, People’s Republic of China
| | - Jing-Hui Yang
- Beijing National Laboratory
for Molecular Sciences, Key Laboratory of Bioorganic Chemistry and
Molecular Engineering of Ministry of Education, Key Laboratory of
Polymer Chemistry and Physics of Ministry of Education, Center for
Soft Matter Science and Engineering, College of Chemistry and Molecular
Engineering, Peking University, Beijing 100871, People’s Republic of China
| | - Qi-Ran Chen
- Beijing National Laboratory
for Molecular Sciences, Key Laboratory of Bioorganic Chemistry and
Molecular Engineering of Ministry of Education, Key Laboratory of
Polymer Chemistry and Physics of Ministry of Education, Center for
Soft Matter Science and Engineering, College of Chemistry and Molecular
Engineering, Peking University, Beijing 100871, People’s Republic of China
| | - Jie-Yu Wang
- Beijing National Laboratory
for Molecular Sciences, Key Laboratory of Bioorganic Chemistry and
Molecular Engineering of Ministry of Education, Key Laboratory of
Polymer Chemistry and Physics of Ministry of Education, Center for
Soft Matter Science and Engineering, College of Chemistry and Molecular
Engineering, Peking University, Beijing 100871, People’s Republic of China
| | - Jian Pei
- Beijing National Laboratory
for Molecular Sciences, Key Laboratory of Bioorganic Chemistry and
Molecular Engineering of Ministry of Education, Key Laboratory of
Polymer Chemistry and Physics of Ministry of Education, Center for
Soft Matter Science and Engineering, College of Chemistry and Molecular
Engineering, Peking University, Beijing 100871, People’s Republic of China
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38
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Warner AJ, Churn A, McGough JS, Ingleson MJ. BCl
3
‐Induced Annulative Oxo‐ and Thioboration for the Formation of C3‐Borylated Benzofurans and Benzothiophenes. Angew Chem Int Ed Engl 2016. [DOI: 10.1002/ange.201610014] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Affiliation(s)
- Andrew J. Warner
- School of Chemistry University of Manchester Oxford Road Manchester M13 9PL UK
| | - Anna Churn
- School of Chemistry University of Manchester Oxford Road Manchester M13 9PL UK
| | - John S. McGough
- School of Chemistry University of Manchester Oxford Road Manchester M13 9PL UK
| | - Michael J. Ingleson
- School of Chemistry University of Manchester Oxford Road Manchester M13 9PL UK
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39
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Warner AJ, Churn A, McGough JS, Ingleson MJ. BCl 3 -Induced Annulative Oxo- and Thioboration for the Formation of C3-Borylated Benzofurans and Benzothiophenes. Angew Chem Int Ed Engl 2016; 56:354-358. [PMID: 27897368 PMCID: PMC5396270 DOI: 10.1002/anie.201610014] [Citation(s) in RCA: 63] [Impact Index Per Article: 7.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/13/2016] [Indexed: 11/06/2022]
Abstract
BCl3 -induced borylative cyclization of aryl-alkynes possessing ortho-EMe (E=S, O) groups represents a simple, metal-free method for the formation of C3-borylated benzothiophenes and benzofurans. The dichloro(heteroaryl)borane primary products can be protected to form synthetically ubiquitous pinacol boronate esters or used in situ in Suzuki-Miyaura cross couplings to generate 2,3-disubstituted heteroarenes from simple alkyne precursors in one pot. In a number of cases alkyne trans-haloboration occurs alongside, or instead of, borylative cyclization and the factors controlling the reaction outcome are determined.
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Affiliation(s)
- Andrew J Warner
- School of Chemistry, University of Manchester, Oxford Road, Manchester, M13 9PL, UK
| | - Anna Churn
- School of Chemistry, University of Manchester, Oxford Road, Manchester, M13 9PL, UK
| | - John S McGough
- School of Chemistry, University of Manchester, Oxford Road, Manchester, M13 9PL, UK
| | - Michael J Ingleson
- School of Chemistry, University of Manchester, Oxford Road, Manchester, M13 9PL, UK
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40
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Wilkins LC, Melen RL. Enantioselective Main Group Catalysis: Modern Catalysts for Organic Transformations. Coord Chem Rev 2016. [DOI: 10.1016/j.ccr.2016.07.011] [Citation(s) in RCA: 85] [Impact Index Per Article: 10.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
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41
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Wilkins LC, Günther BAR, Walther M, Lawson JR, Wirth T, Melen RL. Contrasting Frustrated Lewis Pair Reactivity with Selenium- and Boron-Based Lewis Acids. Angew Chem Int Ed Engl 2016; 55:11292-5. [PMID: 27484052 PMCID: PMC5113806 DOI: 10.1002/anie.201605239] [Citation(s) in RCA: 29] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/29/2016] [Indexed: 01/11/2023]
Abstract
The activation of π-bonds in diynyl esters has been investigated by using soft and hard Lewis acids. In the case of the soft selenium Lewis acid PhSeCl, sequential activation of the alkyne bonds leads initially to an isocoumarin (1 equiv PhSeCl) and then to a tetracyclic conjugated structure with the isocoumarin subunit fused to a benzoselenopyran (3 equiv PhSeCl). Conversely, the reaction with the hard Lewis acidic borane B(C6 F5 )3 initiates a cascade reaction to yield a complex π-conjugated system containing phthalide and indene subunits.
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Affiliation(s)
- Lewis C Wilkins
- School of Chemistry, Cardiff University, Main Building, Park Place, Cardiff, Cymru/Wales, CF10 3AT, UK
| | - Benjamin A R Günther
- School of Chemistry, Cardiff University, Main Building, Park Place, Cardiff, Cymru/Wales, CF10 3AT, UK
| | - Melanie Walther
- School of Chemistry, Cardiff University, Main Building, Park Place, Cardiff, Cymru/Wales, CF10 3AT, UK
| | - James R Lawson
- School of Chemistry, Cardiff University, Main Building, Park Place, Cardiff, Cymru/Wales, CF10 3AT, UK
| | - Thomas Wirth
- School of Chemistry, Cardiff University, Main Building, Park Place, Cardiff, Cymru/Wales, CF10 3AT, UK
| | - Rebecca L Melen
- School of Chemistry, Cardiff University, Main Building, Park Place, Cardiff, Cymru/Wales, CF10 3AT, UK.
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42
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Affiliation(s)
- Elena Buñuel
- Departamento de Química Orgánica; Facultad de Ciencias; Universidad Autónoma de Madrid; Av. Francisco Tomás y Valiente 7, Cantoblanco 28049 Madrid Spain
| | - Diego J. Cárdenas
- Departamento de Química Orgánica; Facultad de Ciencias; Universidad Autónoma de Madrid; Av. Francisco Tomás y Valiente 7, Cantoblanco 28049 Madrid Spain
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43
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Wilkins LC, Lawson JR, Wieneke P, Rominger F, Hashmi ASK, Hansmann MM, Melen RL. The Propargyl Rearrangement to Functionalised Allyl-Boron and Borocation Compounds. Chemistry 2016; 22:14618-24. [PMID: 27538742 DOI: 10.1002/chem.201602719] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/08/2016] [Indexed: 11/08/2022]
Abstract
A diverse range of Lewis acidic alkyl, vinyl and aryl boranes and borenium compounds that are capable of new carbon-carbon bond formation through selective migratory group transfer have been synthesised. Utilising a series of heteroleptic boranes [PhB(C6 F5 )2 (1), PhCH2 CH2 B(C6 F5 )2 (2), and E-B(C6 F5 )2 (C6 F5 )C=C(I)R (R=Ph 3 a, nBu 3 b)] and borenium cations [phenylquinolatoborenium cation ([QOBPh][AlCl4 ], 4)], it has been shown that these boron-based compounds are capable of producing novel allyl- boron and boronium compounds through complex rearrangement reactions with various propargyl esters and carbamates. These reactions yield highly functionalised, synthetically useful boron substituted organic compounds with substantial molecular complexity in a one-pot reaction.
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Affiliation(s)
- Lewis C Wilkins
- School of Chemistry, Main Building, Cardiff University, Cardiff, CF10 3AT, Cymru/Wales, UK
| | - James R Lawson
- School of Chemistry, Main Building, Cardiff University, Cardiff, CF10 3AT, Cymru/Wales, UK
| | - Philipp Wieneke
- Organisch-Chemisches Institut, Ruprecht-Karls-Universität Heidelberg, Im Neuenheimer Feld 270, 69120, Heidelberg, Germany
| | - Frank Rominger
- Organisch-Chemisches Institut, Ruprecht-Karls-Universität Heidelberg, Im Neuenheimer Feld 270, 69120, Heidelberg, Germany
| | - A Stephen K Hashmi
- Organisch-Chemisches Institut, Ruprecht-Karls-Universität Heidelberg, Im Neuenheimer Feld 270, 69120, Heidelberg, Germany.,Chemistry Department, Faculty of Science, King Abdulaziz University (KAU), Jeddah, 21589, Saudi Arabia
| | - Max M Hansmann
- Organisch-Chemisches Institut, Ruprecht-Karls-Universität Heidelberg, Im Neuenheimer Feld 270, 69120, Heidelberg, Germany
| | - Rebecca L Melen
- School of Chemistry, Main Building, Cardiff University, Cardiff, CF10 3AT, Cymru/Wales, UK.
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44
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Pan F, Li XL, Chen XM, Shu C, Ruan PP, Shen CH, Lu X, Ye LW. Catalytic Ynamide Oxidation Strategy for the Preparation of α-Functionalized Amides. ACS Catal 2016. [DOI: 10.1021/acscatal.6b01599] [Citation(s) in RCA: 62] [Impact Index Per Article: 7.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
Affiliation(s)
- Fei Pan
- State
Key Laboratory of Physical Chemistry of Solid Surfaces and Key Laboratory
for Chemical Biology of Fujian Province, Department of Chemistry, Xiamen University, Xiamen 361005, China
| | - Xin-Ling Li
- State
Key Laboratory of Physical Chemistry of Solid Surfaces and Key Laboratory
for Chemical Biology of Fujian Province, Department of Chemistry, Xiamen University, Xiamen 361005, China
| | - Xiu-Mei Chen
- State
Key Laboratory of Physical Chemistry of Solid Surfaces and Center
for Theoretical Chemistry, Department of Chemistry, Xiamen University, Xiamen 361005, China
| | - Chao Shu
- State
Key Laboratory of Physical Chemistry of Solid Surfaces and Key Laboratory
for Chemical Biology of Fujian Province, Department of Chemistry, Xiamen University, Xiamen 361005, China
| | - Peng-Peng Ruan
- State
Key Laboratory of Physical Chemistry of Solid Surfaces and Key Laboratory
for Chemical Biology of Fujian Province, Department of Chemistry, Xiamen University, Xiamen 361005, China
| | - Cang-Hai Shen
- State
Key Laboratory of Physical Chemistry of Solid Surfaces and Key Laboratory
for Chemical Biology of Fujian Province, Department of Chemistry, Xiamen University, Xiamen 361005, China
| | - Xin Lu
- State
Key Laboratory of Physical Chemistry of Solid Surfaces and Center
for Theoretical Chemistry, Department of Chemistry, Xiamen University, Xiamen 361005, China
| | - Long-Wu Ye
- State
Key Laboratory of Physical Chemistry of Solid Surfaces and Key Laboratory
for Chemical Biology of Fujian Province, Department of Chemistry, Xiamen University, Xiamen 361005, China
- State
Key Laboratory of Organometallic Chemistry, Shanghai Institute of
Organic Chemistry, Chinese Academy of Sciences, Shanghai 200032, China
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45
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Wilkins LC, Günther BAR, Walther M, Lawson JR, Wirth T, Melen RL. Gegensätzliche Reaktivität frustrierter Lewis-Paare mit Selen- und Bor-basierten Lewis-Säuren. Angew Chem Int Ed Engl 2016. [DOI: 10.1002/ange.201605239] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
Affiliation(s)
- Lewis C. Wilkins
- School of Chemistry; Cardiff University; Main Building, Park Place Cardiff Cymru/Wales CF10 3AT Großbritannien
| | - Benjamin A. R. Günther
- School of Chemistry; Cardiff University; Main Building, Park Place Cardiff Cymru/Wales CF10 3AT Großbritannien
| | - Melanie Walther
- School of Chemistry; Cardiff University; Main Building, Park Place Cardiff Cymru/Wales CF10 3AT Großbritannien
| | - James R. Lawson
- School of Chemistry; Cardiff University; Main Building, Park Place Cardiff Cymru/Wales CF10 3AT Großbritannien
| | - Thomas Wirth
- School of Chemistry; Cardiff University; Main Building, Park Place Cardiff Cymru/Wales CF10 3AT Großbritannien
| | - Rebecca L. Melen
- School of Chemistry; Cardiff University; Main Building, Park Place Cardiff Cymru/Wales CF10 3AT Großbritannien
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46
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Berliner Wissenschaftspreis: P. Hegemann / Clara Immerwahr Award: R. L. Melen / Chemistry for the Future Solvay Prize: B. L. Feringa / Giulio Natta Medal and Lecture Award: K. Kohse-Höinghaus. Angew Chem Int Ed Engl 2016; 55:2973. [DOI: 10.1002/anie.201600290] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
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47
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Berliner Wissenschaftspreis: P. Hegemann / Chemistry for the Future Solvay Prize: B. L. Feringa / Clara-Immerwahr-Preis: R. L. Melen / Giulio-Natta-Medaille und -Vorlesung: K. Kohse-Höinghaus. Angew Chem Int Ed Engl 2016. [DOI: 10.1002/ange.201600290] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
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48
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Wilkins LC, Hamilton HB, Kariuki BM, Hashmi ASK, Hansmann MM, Melen RL. Lewis acid–base 1,2-addition reactions: synthesis of pyrylium borates from en-ynoate precursors. Dalton Trans 2016; 45:5929-32. [PMID: 26435394 DOI: 10.1039/c5dt03340c] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022]
Abstract
Treatment of methyl (Z)-2-alken-4-ynoates with the strong Lewis acid tris(pentafluorophenyl) borane, B(C6F5)3, yield 2,5,6-substituted zwitterionic pyrylium borate species via an intramolecular 6-endo-dig cyclisation reaction.
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Affiliation(s)
- Lewis C. Wilkins
- School of Chemistry
- Main Building
- Cardiff University
- Cardiff CF10 3AT
- UK
| | - Hugh B. Hamilton
- School of Chemistry
- Main Building
- Cardiff University
- Cardiff CF10 3AT
- UK
| | - Benson M. Kariuki
- School of Chemistry
- Main Building
- Cardiff University
- Cardiff CF10 3AT
- UK
| | - A. Stephen K. Hashmi
- Organisch-Chemisches Institut
- Ruprecht-Karls-Universität Heidelberg
- 69120 Heidelberg
- Germany
- Chemistry Department
| | - Max M. Hansmann
- Organisch-Chemisches Institut
- Ruprecht-Karls-Universität Heidelberg
- 69120 Heidelberg
- Germany
| | - Rebecca L. Melen
- School of Chemistry
- Main Building
- Cardiff University
- Cardiff CF10 3AT
- UK
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49
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Hansmann MM, Melen RL, Rudolph M, Rominger F, Wadepohl H, Stephan DW, Hashmi ASK. Cyclopropanation/Carboboration Reactions of Enynes with B(C6F5)3. J Am Chem Soc 2015; 137:15469-77. [PMID: 26580316 DOI: 10.1021/jacs.5b09311] [Citation(s) in RCA: 73] [Impact Index Per Article: 8.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023]
Abstract
Stoichiometric reaction of B(C6F5)3 with 1,6-enynes is shown to proceed via initial cyclopropanation and formal 1,1-carboboration. Depending on the substitution on the alkene moiety, subsequent ring-opening of the cyclopropane affords either cyclopentane or cyclohexane derivatives in which the C6F5 and B(C6F5)2 adopt a 1,4-positioning. Mechanistically, this transformation involves π-activation of the alkyne moiety, which triggers cyclopropanation, followed by carboboration. Both the cyclopropanation and subsequent ring-opening are shown to be stereospecific. Both cyclopropanation and 1,4-carboborated products were employed as Lewis acid components in frustrated Lewis pair activation of H2 and CO2.
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Affiliation(s)
- Max M Hansmann
- Organisch-Chemisches Institut, Ruprecht-Karls-Universität Heidelberg , Im Neuenheimer Feld 270, 69120 Heidelberg, Germany
| | - Rebecca L Melen
- School of Chemistry, Cardiff University , Main Building, Cardiff, CF10 3AT, Cymru/Wales, U.K
| | - Matthias Rudolph
- Organisch-Chemisches Institut, Ruprecht-Karls-Universität Heidelberg , Im Neuenheimer Feld 270, 69120 Heidelberg, Germany
| | - Frank Rominger
- Organisch-Chemisches Institut, Ruprecht-Karls-Universität Heidelberg , Im Neuenheimer Feld 270, 69120 Heidelberg, Germany
| | - Hubert Wadepohl
- Anorganisch-Chemisches Institut, Ruprecht-Karls-Universität Heidelberg , Im Neuenheimer Feld 270, 69120 Heidelberg, Germany
| | - Douglas W Stephan
- Department of Chemistry, University of Toronto , 80 Saint George Street, Toronto, Ontario M5S 3H6, Canada
| | - A Stephen K Hashmi
- Organisch-Chemisches Institut, Ruprecht-Karls-Universität Heidelberg , Im Neuenheimer Feld 270, 69120 Heidelberg, Germany.,Chemistry Department, Faculty of Science, King Abdulaziz University (KAU) , Jeddah 21589, Saudi Arabia
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50
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Wilkins LC, Wieneke P, Newman PD, Kariuki BM, Rominger F, Hashmi ASK, Hansmann MM, Melen RL. Pathways to Functionalized Heterocycles: Propargyl Rearrangement using B(C6F5)3. Organometallics 2015. [DOI: 10.1021/acs.organomet.5b00753] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Lewis C. Wilkins
- School
of Chemistry, Cardiff University, Main Building, Cardiff CF10 3AT, Cymru/Wales, U.K
| | - Philipp Wieneke
- Organisch-Chemisches
Institut, Ruprecht-Karls-Universität Heidelberg, Im Neuenheimer
Feld 270, 69120 Heidelberg, Germany
| | - Paul D. Newman
- School
of Chemistry, Cardiff University, Main Building, Cardiff CF10 3AT, Cymru/Wales, U.K
| | - Benson M. Kariuki
- School
of Chemistry, Cardiff University, Main Building, Cardiff CF10 3AT, Cymru/Wales, U.K
| | - Frank Rominger
- Organisch-Chemisches
Institut, Ruprecht-Karls-Universität Heidelberg, Im Neuenheimer
Feld 270, 69120 Heidelberg, Germany
| | - A. Stephen K. Hashmi
- Organisch-Chemisches
Institut, Ruprecht-Karls-Universität Heidelberg, Im Neuenheimer
Feld 270, 69120 Heidelberg, Germany
- Chemistry
Department, King Abdulaziz University (KAU), Jeddah 21589, Saudi Arabia
| | - Max M. Hansmann
- Organisch-Chemisches
Institut, Ruprecht-Karls-Universität Heidelberg, Im Neuenheimer
Feld 270, 69120 Heidelberg, Germany
| | - Rebecca L. Melen
- School
of Chemistry, Cardiff University, Main Building, Cardiff CF10 3AT, Cymru/Wales, U.K
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