1
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Maji S, Rawal P, Ghosh A, Pidiyar K, Al-Thabaiti SA, Gupta P, Maiti D. Metal-free Borylation of α-Naphthamides and Phenylacetic Acid Drug. JACS AU 2024; 4:3679-3689. [PMID: 39328765 PMCID: PMC11423307 DOI: 10.1021/jacsau.4c00660] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 07/23/2024] [Revised: 08/13/2024] [Accepted: 08/14/2024] [Indexed: 09/28/2024]
Abstract
Site-selective C-H borylation is an important strategy for constructing molecular diversity in arenes and heteroarenes. Although transition-metal-catalyzed borylation is well explored, developing metal-free strategies remains scarce. Herein, we developed a straightforward approach for BBr3-mediated selective C-H borylation of naphthamide and phenyl acetamide derivatives under metal-free conditions. This methodology appears to be economical and cost-effective. Successful borylation of drug molecules such as ibuprofen and indoprofen demonstrates the versatility and utility of this metal-free borylation. An exclusive monoselectivity was observed without a trace of diboration. Despite the possibility of forming a 5-membered boronated intermediate at the ortho-position, the selectively 6-membered intermediate paved the way for the formation of the peri-product, which was further supported by detailed computational investigation.
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Affiliation(s)
- Suman Maji
- Department of Chemistry, Indian Institute of Technology Bombay, Powai, Mumbai 400076, India
| | - Parveen Rawal
- Computational Catalysis Center, Department of Chemistry, Indian Institute of Technology Roorkee, Roorkee, Uttarakhand 247667, India
| | - Animesh Ghosh
- Department of Chemistry, Indian Institute of Technology Bombay, Powai, Mumbai 400076, India
| | - Karishma Pidiyar
- Department of Chemistry, Indian Institute of Technology Bombay, Powai, Mumbai 400076, India
| | - Shaeel A Al-Thabaiti
- Department of Chemistry, Faculty of Science, King Abdulaziz University institution, P.O. Box : 80203, Jeddah, 21589, Saudi Arabia
| | - Puneet Gupta
- Computational Catalysis Center, Department of Chemistry, Indian Institute of Technology Roorkee, Roorkee, Uttarakhand 247667, India
- Department of Chemistry, Faculty of ScienceCenter for Sustainable Energy, Indian Institute of Technology Roorkee, Roorkee, Uttarakhand 247667, India
| | - Debabrata Maiti
- Department of Chemistry, Indian Institute of Technology Bombay, Powai, Mumbai 400076, India
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2
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Tran MK, Ready JM. Chemoselective and Stereoselective Allylation of Bis(alkenyl)boronates. Angew Chem Int Ed Engl 2024; 63:e202407824. [PMID: 38781007 PMCID: PMC11347121 DOI: 10.1002/anie.202407824] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/24/2024] [Revised: 05/21/2024] [Accepted: 05/23/2024] [Indexed: 05/25/2024]
Abstract
Bis(alkenyl)boronates react with optically active Ir(π-allyl) species in a process that involves allylation of the more substituted olefin and 1,2-metalate shift of the less substituted olefin. The method constructs valuable enantioenriched tertiary allylic boronic esters with high chemoselectivity, enantioselectivity and diastereoselectivity. Allylic functionalization reactions transform the 1,3-stereodiad to 1,5- and 1,6-stereochemical relationships.
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Affiliation(s)
- Minh-Khoa Tran
- Department of Biochemistry, Division of Chemistry, UT Southwestern Medical Center 5323 Harry Hines Blvd., Dallas, TX 75390-0938 (USA)
| | - Joseph M. Ready
- Department of Biochemistry, Division of Chemistry, UT Southwestern Medical Center 5323 Harry Hines Blvd., Dallas, TX 75390-0938 (USA)
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3
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Kang S, Lv J, Wang T, Wu B, Wang M, Shi Z. Transforming cyclopropanes to enamides via σ-C-C bond eliminative borylation. Nat Commun 2024; 15:7380. [PMID: 39191737 PMCID: PMC11350172 DOI: 10.1038/s41467-024-51484-6] [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: 05/08/2024] [Accepted: 08/07/2024] [Indexed: 08/29/2024] Open
Abstract
Recent strides in C-H borylation have significantly expanded our toolkit for the preparation of organoboronates. Nevertheless, avenues alternative to obtain these compounds via σ-C-C cleavage, thereby facilitating molecular scaffold editing, remain scarce. Several methodologies have been proposed for hydroboration of cyclopropanes by activating C-C bonds, conventionally relying on noble and hazardous metal catalysts to control reaction outcomes. Here, we present a strategy for crafting stereochemically precise γ-borylenamides through ring-opening of cyclopropanes avoiding any metallic entities. Boryl species, generated through a ternary reaction with BCl3, cyclopropanes, and a tertiary amine, selectively undergo C-C bond eliminative borylation under the directing of N-acyl group, thereby ensuring enhanced selectivity and efficiency along the reaction pathway. Such inherently stereoconvergent approach accommodates precursors of diverse geometries, including cis/trans isomeric blends.
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Affiliation(s)
- Shuyu Kang
- State Key Laboratory of Coordination Chemistry, Chemistry and Biomedicine Innovation Center (ChemBIC), School of Chemistry and Chemical Engineering, Nanjing University, Nanjing, Jiangsu, China
| | - Jiahang Lv
- State Key Laboratory of Coordination Chemistry, Chemistry and Biomedicine Innovation Center (ChemBIC), School of Chemistry and Chemical Engineering, Nanjing University, Nanjing, Jiangsu, China.
| | - Tianhang Wang
- State Key Laboratory of Coordination Chemistry, Chemistry and Biomedicine Innovation Center (ChemBIC), School of Chemistry and Chemical Engineering, Nanjing University, Nanjing, Jiangsu, China
| | - Bingcheng Wu
- State Key Laboratory of Coordination Chemistry, Chemistry and Biomedicine Innovation Center (ChemBIC), School of Chemistry and Chemical Engineering, Nanjing University, Nanjing, Jiangsu, China
| | - Minyan Wang
- State Key Laboratory of Coordination Chemistry, Chemistry and Biomedicine Innovation Center (ChemBIC), School of Chemistry and Chemical Engineering, Nanjing University, Nanjing, Jiangsu, China
| | - Zhuangzhi Shi
- State Key Laboratory of Coordination Chemistry, Chemistry and Biomedicine Innovation Center (ChemBIC), School of Chemistry and Chemical Engineering, Nanjing University, Nanjing, Jiangsu, China.
- School of Chemistry and Materials Science, Nanjing Normal University, Nanjing, Jiangsu, China.
- School of Chemistry and Chemical Engineering, Henan Normal University, Xinxiang, Henan, China.
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4
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Lv J, Liang Y, Ouyang Y, Zhang H. Metal-Free ortho C-H Borylation of Thiobenzamides. Org Lett 2024; 26:3709-3714. [PMID: 38691629 DOI: 10.1021/acs.orglett.4c00691] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/03/2024]
Abstract
A BBr3-mediated S-directed ortho C-H borylation of thiobenzamides was developed. A variety of ortho-borylated thiobenzamides were obtained in moderate to good yields with a wide functional group tolerance under simple and metal-free conditions. This transformation provided a convenient and practical route to important functionalized thiobenzamides.
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Affiliation(s)
- Jianxing Lv
- Key Laboratory of Catalysis and Energy Materials Chemistry of Ministry of Education and Hubei Key Laboratory of Catalysis and Materials Science, School of Chemistry and Materials Science, South-Central Minzu University, Wuhan 430074, P. R. China
| | - Yixuan Liang
- Key Laboratory of Catalysis and Energy Materials Chemistry of Ministry of Education and Hubei Key Laboratory of Catalysis and Materials Science, School of Chemistry and Materials Science, South-Central Minzu University, Wuhan 430074, P. R. China
| | - Yepeng Ouyang
- Key Laboratory of Catalysis and Energy Materials Chemistry of Ministry of Education and Hubei Key Laboratory of Catalysis and Materials Science, School of Chemistry and Materials Science, South-Central Minzu University, Wuhan 430074, P. R. China
| | - Hua Zhang
- Key Laboratory of Catalysis and Energy Materials Chemistry of Ministry of Education and Hubei Key Laboratory of Catalysis and Materials Science, School of Chemistry and Materials Science, South-Central Minzu University, Wuhan 430074, P. R. China
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5
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Tanaka S, Yoshii Y, Hattori T. Lewis Acid-Mediated Friedel-Crafts-Type Formylation of Alkenes with Dichloromethyl Methyl Ether in the Presence of Pyridines. J Org Chem 2024; 89:3546-3551. [PMID: 38348870 DOI: 10.1021/acs.joc.3c02059] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 03/02/2024]
Abstract
Various alkenes are formylated with dichloromethyl methyl ether (MOMCl2) by the combined use of SnCl4/2,6-dibromopyridine (B1) or AgOTf/pyridine (B4) via Friedel-Crafts-type reaction. The former reagent combination is mainly applied to α,α-diarylalkenes, while the latter one is applied not only to arylalkenes but also to some alkylalkenes. Vinyl aldehydes are exclusively obtained from alkenes that can possibly afford both allyl and vinyl aldehydes.
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Affiliation(s)
- Shinya Tanaka
- Department of Biomolecular Engineering, Graduate School of Engineering, Tohoku University, 6-6-11 Aramaki-Aoba, Aoba-ku, Sendai 980-8579, Japan
- Environment Conservation Research Institute, Tohoku University, 6-6-04 Aramaki-Aoba, Aoba-ku, Sendai 980-8579, Japan
| | - Yuji Yoshii
- Department of Biomolecular Engineering, Graduate School of Engineering, Tohoku University, 6-6-11 Aramaki-Aoba, Aoba-ku, Sendai 980-8579, Japan
| | - Tetsutaro Hattori
- Department of Biomolecular Engineering, Graduate School of Engineering, Tohoku University, 6-6-11 Aramaki-Aoba, Aoba-ku, Sendai 980-8579, Japan
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6
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Wang T, Wang ZJ, Wang M, Wu L, Fang X, Liang Y, Lv J, Shi Z. Metal-Free Stereoconvergent C-H Borylation of Enamides. Angew Chem Int Ed Engl 2023; 62:e202313205. [PMID: 37721200 DOI: 10.1002/anie.202313205] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/06/2023] [Revised: 09/15/2023] [Accepted: 09/18/2023] [Indexed: 09/19/2023]
Abstract
Enamides, functional derivatives of enamines, play a significant role as synthetic targets. However, the stereoselective synthesis of these molecules has posed a longstanding challenge in organic chemistry, particularly for acyclic enamides that are less thermodynamically stable. In this study, we present a general strategy for constructing β-borylenamides by C-H borylation, which provides a versatile platform for generating the stereodefined enamides. Our approach involves the utilization of metalloid borenium cation, generated through the reaction of BBr3 and enamides in the presence of two different additives, avoiding any exogenous catalyst. Importantly, the stereoconvergent nature of this methodology allows for the use of starting materials with mixed E/Z configurations, thus highlighting the unique advantage of this chemistry. Mechanistic investigations have shed light on the pivotal roles played by the two additives, the reactive boron species, and the phenomenon of stereoconvergence.
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Affiliation(s)
- Tianhang Wang
- State Key Laboratory of Coordination Chemistry, Chemistry and Biomedicine Innovation Center (ChemBIC), School of Chemistry and Chemical Engineering, Nanjing University, Nanjing, Jiangsu, 210093, China
| | - Zheng-Jun Wang
- State Key Laboratory of Coordination Chemistry, Chemistry and Biomedicine Innovation Center (ChemBIC), School of Chemistry and Chemical Engineering, Nanjing University, Nanjing, Jiangsu, 210093, China
- Wenzhou Key Lab of Advanced Energy Storage and Conversion, Zhejiang Province Key Lab of Leather Engineering, College of Chemistry and Materials Engineering, Wenzhou University, Wenzhou, Zhejiang, 325035, China
| | - Minyan Wang
- State Key Laboratory of Coordination Chemistry, Chemistry and Biomedicine Innovation Center (ChemBIC), School of Chemistry and Chemical Engineering, Nanjing University, Nanjing, Jiangsu, 210093, China
| | - Lei Wu
- State Key Laboratory of Coordination Chemistry, Chemistry and Biomedicine Innovation Center (ChemBIC), School of Chemistry and Chemical Engineering, Nanjing University, Nanjing, Jiangsu, 210093, China
| | - Xiaowu Fang
- State Key Laboratory of Coordination Chemistry, Chemistry and Biomedicine Innovation Center (ChemBIC), School of Chemistry and Chemical Engineering, Nanjing University, Nanjing, Jiangsu, 210093, China
| | - Yong Liang
- State Key Laboratory of Coordination Chemistry, Chemistry and Biomedicine Innovation Center (ChemBIC), School of Chemistry and Chemical Engineering, Nanjing University, Nanjing, Jiangsu, 210093, China
| | - Jiahang Lv
- State Key Laboratory of Coordination Chemistry, Chemistry and Biomedicine Innovation Center (ChemBIC), School of Chemistry and Chemical Engineering, Nanjing University, Nanjing, Jiangsu, 210093, China
| | - Zhuangzhi Shi
- State Key Laboratory of Coordination Chemistry, Chemistry and Biomedicine Innovation Center (ChemBIC), School of Chemistry and Chemical Engineering, Nanjing University, Nanjing, Jiangsu, 210093, China
- School of Chemistry and Chemical Engineering, Henan Normal University, Xinxiang, Henan, 453007, China
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7
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Kumar Someswara Ashwathappa P, Higashi T, Desrosiers V, Omaña AA, Fontaine FG. Metal-Free Directed Site-Selective Csp 3 -H Borylation of Saturated Cyclic Amines. Angew Chem Int Ed Engl 2023; 62:e202309295. [PMID: 37535392 DOI: 10.1002/anie.202309295] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/03/2023] [Revised: 08/01/2023] [Accepted: 08/02/2023] [Indexed: 08/04/2023]
Abstract
The borylation of Csp3 -H bonds is a challenging transformation that is typically restricted to transition metal catalysis. Herein, we report the site-selective metal-free Csp3 -H borylation of saturated cyclic amines. It is possible to selectively borylate piperidine derivatives at the α or β positions according to the reaction conditions. The mechanism was supported by NMR spectroscopy, calorimetry experiments and density functional theory (DFT) computations. It suggests that the piperidine is dehydrogenated by complexation with BBr3 to produce an enamine intermediate, which is in turn borylated at either the α or β position according to the reaction conditions.
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Affiliation(s)
| | - Takuya Higashi
- Department of Chemistry and Biotechnology, Graduate School of Engineering, The University of Tokyo, Bunkyo-Ku, Tokyo 113-8656, Japan
| | - Vincent Desrosiers
- Département de Chimie, Université Laval, 1045 Avenue de la Médecine, Québec, Québec G1 V 0 A6, Canada
| | - Alvaro A Omaña
- Département de Chimie, Université Laval, 1045 Avenue de la Médecine, Québec, Québec G1 V 0 A6, Canada
| | - Frédéric-Georges Fontaine
- Département de Chimie, Université Laval, 1045 Avenue de la Médecine, Québec, Québec G1 V 0 A6, Canada
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8
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Peng PY, Zhang GS, Gong ML, Zhang JW, Liu XL, Gao D, Lin GQ, Li QH, Tian P. A practical preparation of bicyclic boronates via metal-free heteroatom-directed alkenyl sp 2-C‒H borylation. Commun Chem 2023; 6:176. [PMID: 37612464 PMCID: PMC10447525 DOI: 10.1038/s42004-023-00976-5] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/14/2022] [Accepted: 08/07/2023] [Indexed: 08/25/2023] Open
Abstract
Bicyclic boronates play critical roles in the discovery of functional materials and antibacterial agents, especially against deadly bacterial pathogens. Their practical and convenient preparation is in high demand but with great challenge. Herein, we report an efficient strategy for the preparation of bicyclic boronates through metal-free heteroatom-directed alkenyl sp2-C‒H borylation. This synthetic approach exhibits good functional group compatibility, and the corresponding boronates bearing halides, aryls, acyclic and cyclic frameworks are obtained with high yields (43 examples, up to 95% yield). Furthermore, a gram-scale experiment is conducted, and downstream transformations of the bicyclic boronates are pursued to afford natural products, drug scaffolds, and chiral hemiboronic acid catalysts.
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Affiliation(s)
- Pei-Ying Peng
- The Research Center of Chiral Drugs, Shanghai Frontiers Science Center for TCM Chemical Biology, Innovation Research Institute of Traditional Chinese Medicine, Shanghai University of Traditional Chinese Medicine, 1200 Cailun Road, Shanghai, 201203, China
- China-Thailand Joint Research Institute of Natural Medicine, Shanghai University of Traditional Chinese Medicine, 1200 Cailun Road, Shanghai, 201203, China
| | - Gui-Shan Zhang
- The Research Center of Chiral Drugs, Shanghai Frontiers Science Center for TCM Chemical Biology, Innovation Research Institute of Traditional Chinese Medicine, Shanghai University of Traditional Chinese Medicine, 1200 Cailun Road, Shanghai, 201203, China
- China-Thailand Joint Research Institute of Natural Medicine, Shanghai University of Traditional Chinese Medicine, 1200 Cailun Road, Shanghai, 201203, China
| | - Mei-Ling Gong
- The Research Center of Chiral Drugs, Shanghai Frontiers Science Center for TCM Chemical Biology, Innovation Research Institute of Traditional Chinese Medicine, Shanghai University of Traditional Chinese Medicine, 1200 Cailun Road, Shanghai, 201203, China
- China-Thailand Joint Research Institute of Natural Medicine, Shanghai University of Traditional Chinese Medicine, 1200 Cailun Road, Shanghai, 201203, China
| | - Jian-Wei Zhang
- The Research Center of Chiral Drugs, Shanghai Frontiers Science Center for TCM Chemical Biology, Innovation Research Institute of Traditional Chinese Medicine, Shanghai University of Traditional Chinese Medicine, 1200 Cailun Road, Shanghai, 201203, China
- China-Thailand Joint Research Institute of Natural Medicine, Shanghai University of Traditional Chinese Medicine, 1200 Cailun Road, Shanghai, 201203, China
| | - Xi-Liang Liu
- The Research Center of Chiral Drugs, Shanghai Frontiers Science Center for TCM Chemical Biology, Innovation Research Institute of Traditional Chinese Medicine, Shanghai University of Traditional Chinese Medicine, 1200 Cailun Road, Shanghai, 201203, China
- China-Thailand Joint Research Institute of Natural Medicine, Shanghai University of Traditional Chinese Medicine, 1200 Cailun Road, Shanghai, 201203, China
| | - Dingding Gao
- The Research Center of Chiral Drugs, Shanghai Frontiers Science Center for TCM Chemical Biology, Innovation Research Institute of Traditional Chinese Medicine, Shanghai University of Traditional Chinese Medicine, 1200 Cailun Road, Shanghai, 201203, China
- China-Thailand Joint Research Institute of Natural Medicine, Shanghai University of Traditional Chinese Medicine, 1200 Cailun Road, Shanghai, 201203, China
| | - Guo-Qiang Lin
- The Research Center of Chiral Drugs, Shanghai Frontiers Science Center for TCM Chemical Biology, Innovation Research Institute of Traditional Chinese Medicine, Shanghai University of Traditional Chinese Medicine, 1200 Cailun Road, Shanghai, 201203, China
- China-Thailand Joint Research Institute of Natural Medicine, Shanghai University of Traditional Chinese Medicine, 1200 Cailun Road, Shanghai, 201203, China
| | - Qing-Hua Li
- The Research Center of Chiral Drugs, Shanghai Frontiers Science Center for TCM Chemical Biology, Innovation Research Institute of Traditional Chinese Medicine, Shanghai University of Traditional Chinese Medicine, 1200 Cailun Road, Shanghai, 201203, China.
- China-Thailand Joint Research Institute of Natural Medicine, Shanghai University of Traditional Chinese Medicine, 1200 Cailun Road, Shanghai, 201203, China.
| | - Ping Tian
- The Research Center of Chiral Drugs, Shanghai Frontiers Science Center for TCM Chemical Biology, Innovation Research Institute of Traditional Chinese Medicine, Shanghai University of Traditional Chinese Medicine, 1200 Cailun Road, Shanghai, 201203, China.
- China-Thailand Joint Research Institute of Natural Medicine, Shanghai University of Traditional Chinese Medicine, 1200 Cailun Road, Shanghai, 201203, China.
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9
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Rej S, Chatani N. Regioselective Transition‐Metal‐Free C(sp
2
)−H Borylation: A Subject of Practical and Ongoing Interest in Synthetic Organic Chemistry. Angew Chem Int Ed Engl 2022; 61:e202209539. [DOI: 10.1002/anie.202209539] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/30/2022] [Indexed: 12/22/2022]
Affiliation(s)
- Supriya Rej
- Department of Applied Chemistry Faculty of Engineering and Research Center for Environmental Preservation Osaka University Suita, Osaka 565-0871 Japan
- Institut für Chemie Technische Universität Berlin Strasse des 17. Juni 115 10623 Berlin Germany
| | - Naoto Chatani
- Department of Applied Chemistry Faculty of Engineering and Research Center for Environmental Preservation Osaka University Suita, Osaka 565-0871 Japan
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10
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Rej S, Chatani N. Regio‐Selective Transition‐Metal‐Free C(sp2)‒H Borylation: A Subject of Practical and Ongoing Interest in Synthetic Organic Chemistry. Angew Chem Int Ed Engl 2022. [DOI: 10.1002/ange.202209539] [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]
Affiliation(s)
- Supriya Rej
- Osaka University School of Engineering Graduate School of Engineering: Osaka Daigaku Kogakubu Daigakuin Kogaku Kenkyuka Applied Chemistry JAPAN
| | - Naoto Chatani
- Osaka University School of Engineering Graduate School of Engineering: Osaka Daigaku Kogakubu Daigakuin Kogaku Kenkyuka Applied Chemistry 2-1 Yamadaoka 566-0871 Suita, Osaka JAPAN
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11
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Wu G, Yang Z, Xu X, Hao L, Chen L, Wang Y, Ji Y. Metal-Free Boron-Mediated ortho-C-H Hydroxylation of N-Benzyl-3,4,5-tribromopyrazoles. Org Lett 2022; 24:3570-3575. [PMID: 35512319 DOI: 10.1021/acs.orglett.2c01347] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
A novel route has been reported for C-H hydroxylation of benzyl compounds directed by a 3,4,5-tribromopyrazole auxiliary via boronation/oxidation using BBr3 and NaBO3·4H2O. The strategy exhibits outstanding site selectivity and affords the corresponding phenols in moderate to excellent yields under metal-free conditions. Besides, this protocol can be achieved in one pot, which is highly promising as a practical method for use in a multistep organic synthetic process.
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Affiliation(s)
- Gaorong Wu
- Engineering Research Center of Pharmaceutical Process Chemistry, Ministry of Education, School of Pharmacy, East China University of Science and Technology, 130 Meilong Road, Shanghai 200237, PR China
| | - Zhaoziyuan Yang
- Engineering Research Center of Pharmaceutical Process Chemistry, Ministry of Education, School of Pharmacy, East China University of Science and Technology, 130 Meilong Road, Shanghai 200237, PR China
| | - Xiaobo Xu
- Engineering Research Center of Pharmaceutical Process Chemistry, Ministry of Education, School of Pharmacy, East China University of Science and Technology, 130 Meilong Road, Shanghai 200237, PR China
| | - Liqiang Hao
- Engineering Research Center of Pharmaceutical Process Chemistry, Ministry of Education, School of Pharmacy, East China University of Science and Technology, 130 Meilong Road, Shanghai 200237, PR China
| | - Lu Chen
- Engineering Research Center of Pharmaceutical Process Chemistry, Ministry of Education, School of Pharmacy, East China University of Science and Technology, 130 Meilong Road, Shanghai 200237, PR China
| | - Yangyang Wang
- Engineering Research Center of Pharmaceutical Process Chemistry, Ministry of Education, School of Pharmacy, East China University of Science and Technology, 130 Meilong Road, Shanghai 200237, PR China
| | - Yafei Ji
- Engineering Research Center of Pharmaceutical Process Chemistry, Ministry of Education, School of Pharmacy, East China University of Science and Technology, 130 Meilong Road, Shanghai 200237, PR China
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12
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Wu G, Xu X, Wang S, Chen L, Pang B, Ma T, Ji Y. Metal-free directed C−H borylation of 2-(N-methylanilino)-5-fluoropyridines and 2-benzyl-5-fluoropyridines. CHINESE CHEM LETT 2022. [DOI: 10.1016/j.cclet.2021.09.081] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
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13
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Yamamoto K, Yamada I, Kameyama M, Yamamoto K, Nakamura Y. Synthesis of Carbazole-containing 1,2-Azaborine Derivatives Using Bora-Friedel–Crafts Reaction and Their Photophysical Properties. CHEM LETT 2022. [DOI: 10.1246/cl.210597] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
Affiliation(s)
- Koji Yamamoto
- Division of Molecular Science, Faculty of Science and Technology, Gunma University, 1-5-1 Tenjin-cho, Kiryu, Gunma 376-8515, Japan
| | - Itsuki Yamada
- Division of Molecular Science, Faculty of Science and Technology, Gunma University, 1-5-1 Tenjin-cho, Kiryu, Gunma 376-8515, Japan
| | - Masaru Kameyama
- Division of Molecular Science, Faculty of Science and Technology, Gunma University, 1-5-1 Tenjin-cho, Kiryu, Gunma 376-8515, Japan
| | - Koji Yamamoto
- Department of Chemical Science and Engineering, Tokyo Institute of Technology, O-okayama, Meguro-ku, Tokyo 152-8552, Japan
| | - Yosuke Nakamura
- Division of Molecular Science, Faculty of Science and Technology, Gunma University, 1-5-1 Tenjin-cho, Kiryu, Gunma 376-8515, Japan
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14
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Sadek O, Le Gac A, Hidalgo N, Mallet-Ladeira S, Miqueu K, Bouhadir G, Bourissou D. Metal-Free Phosphorus-Directed Borylation of C(sp 2 )-H Bonds. Angew Chem Int Ed Engl 2022; 61:e202110102. [PMID: 34719849 DOI: 10.1002/anie.202110102] [Citation(s) in RCA: 11] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/28/2021] [Revised: 10/15/2021] [Indexed: 01/06/2023]
Abstract
Spectacular progress has recently been achieved in transition metal-catalyzed C-H borylation of phosphines as well as directed electrophilic C-H borylation. As shown here, P-directed electrophilic borylation provides a new, straightforward, and efficient access to phosphine-boranes. It operates under metal-free conditions and leverages simple, readily available substrates. It is applicable to a broad range of backbones (naphthyl, biphenyl, N-phenylpyrrole, binaphthyl, benzyl, naphthylmethyl) and gives facile access to various substitution patterns at boron (by varying the boron electrophile or post-derivatizing the borane moiety). NMR monitoring supports the involvement of P-stabilized borenium cations as key intermediates. DFT calculations reveal the existence and stabilizing effect of π-arene/boron interactions in the (biphenyl)(i-Pr)2 P→BBr2 + species.
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Affiliation(s)
- Omar Sadek
- CNRS/Université Paul Sabatier, Laboratoire Hetérochimie Fondamentale et Appliquée (LHFA, UMR 5069), 118 Route de Narbonne, 31062 Cedex 09, Toulouse, France
| | - Arnaud Le Gac
- CNRS/Université Paul Sabatier, Laboratoire Hetérochimie Fondamentale et Appliquée (LHFA, UMR 5069), 118 Route de Narbonne, 31062 Cedex 09, Toulouse, France
| | - Nereida Hidalgo
- CNRS/Université Paul Sabatier, Laboratoire Hetérochimie Fondamentale et Appliquée (LHFA, UMR 5069), 118 Route de Narbonne, 31062 Cedex 09, Toulouse, France
| | - Sonia Mallet-Ladeira
- Institut de Chimie de Toulouse (FR 2599), 118 Route de Narbonne, 31062 Cedex 09, Toulouse, France
| | - Karinne Miqueu
- CNRS/Université de Pau et des Pays de l'Adour, E2S-UPPA, Institut des Sciences Analytiques et Physico-Chimie pour l'Environnement et les Matériaux (IPREM, UMR 5254), Hélioparc, 2 Avenue du Président Angot, 64053, Pau Cedex 09, France
| | - Ghenwa Bouhadir
- CNRS/Université Paul Sabatier, Laboratoire Hetérochimie Fondamentale et Appliquée (LHFA, UMR 5069), 118 Route de Narbonne, 31062 Cedex 09, Toulouse, France
| | - Didier Bourissou
- CNRS/Université Paul Sabatier, Laboratoire Hetérochimie Fondamentale et Appliquée (LHFA, UMR 5069), 118 Route de Narbonne, 31062 Cedex 09, Toulouse, France
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15
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Sadek O, Le Gac A, Hidalgo N, Mallet‐Ladeira S, Miqueu K, Bouhadir G, Bourissou D. Metal‐Free Phosphorus‐Directed Borylation of C(sp
2
)−H Bonds. Angew Chem Int Ed Engl 2022. [DOI: 10.1002/ange.202110102] [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]
Affiliation(s)
- Omar Sadek
- CNRS/Université Paul Sabatier Laboratoire Hetérochimie Fondamentale et Appliquée (LHFA, UMR 5069) 118 Route de Narbonne 31062 Cedex 09 Toulouse France
| | - Arnaud Le Gac
- CNRS/Université Paul Sabatier Laboratoire Hetérochimie Fondamentale et Appliquée (LHFA, UMR 5069) 118 Route de Narbonne 31062 Cedex 09 Toulouse France
| | - Nereida Hidalgo
- CNRS/Université Paul Sabatier Laboratoire Hetérochimie Fondamentale et Appliquée (LHFA, UMR 5069) 118 Route de Narbonne 31062 Cedex 09 Toulouse France
| | - Sonia Mallet‐Ladeira
- Institut de Chimie de Toulouse (FR 2599) 118 Route de Narbonne 31062 Cedex 09 Toulouse France
| | - Karinne Miqueu
- CNRS/Université de Pau et des Pays de l'Adour, E2S-UPPA Institut des Sciences Analytiques et Physico-Chimie pour l'Environnement et les Matériaux (IPREM, UMR 5254) Hélioparc 2 Avenue du Président Angot 64053 Pau Cedex 09 France
| | - Ghenwa Bouhadir
- CNRS/Université Paul Sabatier Laboratoire Hetérochimie Fondamentale et Appliquée (LHFA, UMR 5069) 118 Route de Narbonne 31062 Cedex 09 Toulouse France
| | - Didier Bourissou
- CNRS/Université Paul Sabatier Laboratoire Hetérochimie Fondamentale et Appliquée (LHFA, UMR 5069) 118 Route de Narbonne 31062 Cedex 09 Toulouse France
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16
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Li S, Hu C, Cui X, Zhang J, Liu LL, Wu L. Site‐Fixed Hydroboration of Terminal and Internal Alkenes using BX
3
/
i
Pr
2
NEt**. Angew Chem Int Ed Engl 2021. [DOI: 10.1002/ange.202111978] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Affiliation(s)
- Sida Li
- State Key Laboratory for Oxo Synthesis and Selective Oxidation Suzhou Research Institute of LICP Lanzhou Institute of Chemical Physics (LICP) Chinese Academy of Sciences Lanzhou 730000 China
- University of Chinese Academy of Sciences Beijing 100049 China
| | - Chenyang Hu
- Shenzhen Grubbs Institute and Department of Chemistry Southern University of Science and Technology Shenzhen 518055 China
| | - Xin Cui
- State Key Laboratory for Oxo Synthesis and Selective Oxidation Suzhou Research Institute of LICP Lanzhou Institute of Chemical Physics (LICP) Chinese Academy of Sciences Lanzhou 730000 China
| | - Jiong Zhang
- State Key Laboratory for Oxo Synthesis and Selective Oxidation Suzhou Research Institute of LICP Lanzhou Institute of Chemical Physics (LICP) Chinese Academy of Sciences Lanzhou 730000 China
- University of Chinese Academy of Sciences Beijing 100049 China
| | - Liu Leo Liu
- Shenzhen Grubbs Institute and Department of Chemistry Southern University of Science and Technology Shenzhen 518055 China
| | - Lipeng Wu
- State Key Laboratory for Oxo Synthesis and Selective Oxidation Suzhou Research Institute of LICP Lanzhou Institute of Chemical Physics (LICP) Chinese Academy of Sciences Lanzhou 730000 China
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17
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Wang Z, Wu J, Lamine W, Li B, Sotiropoulos JM, Chrostowska A, Miqueu K, Liu SY. C-Boron Enolates Enable Palladium Catalyzed Carboboration of Internal 1,3-Enynes. Angew Chem Int Ed Engl 2021; 60:21231-21236. [PMID: 34245074 DOI: 10.1002/anie.202108534] [Citation(s) in RCA: 12] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/26/2021] [Indexed: 12/17/2022]
Abstract
A new family of carbon-bound boron enolates, generated by a kinetically controlled halogen exchange between chlorocatecholborane and silylketene acetals, is described. These C-boron enolates are demonstrated to activate 1,3-enyne substrates in the presence of a Pd0 /Senphos ligand complex, resulting in the first examples of a carboboration reaction of an alkyne with enolate-equivalent nucleophiles. Highly substituted dienyl boron building blocks are produced in excellent site-, regio-, and diastereoselectivity by the described catalytic cis-carboboration reaction.
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Affiliation(s)
- Ziyong Wang
- Department of Chemistry, Boston College, Chestnut Hill, MA, 02467, USA
| | - Jason Wu
- Department of Chemistry, Boston College, Chestnut Hill, MA, 02467, USA
| | - Walid Lamine
- Université de Pau et des Pays de l'Adour, E2S UPPA, CNRS, IPREM, UMR 5254, 64053, Pau cedex 09, France
| | - Bo Li
- Department of Chemistry, Boston College, Chestnut Hill, MA, 02467, USA
| | - Jean-Marc Sotiropoulos
- Université de Pau et des Pays de l'Adour, E2S UPPA, CNRS, IPREM, UMR 5254, 64053, Pau cedex 09, France
| | - Anna Chrostowska
- Université de Pau et des Pays de l'Adour, E2S UPPA, CNRS, IPREM, UMR 5254, 64053, Pau cedex 09, France
| | - Karinne Miqueu
- Université de Pau et des Pays de l'Adour, E2S UPPA, CNRS, IPREM, UMR 5254, 64053, Pau cedex 09, France
| | - Shih-Yuan Liu
- Department of Chemistry, Boston College, Chestnut Hill, MA, 02467, USA.,Université de Pau et des Pays de l'Adour, E2S UPPA, CNRS, IPREM, UMR 5254, 64053, Pau cedex 09, France
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18
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Wang Z, Wu J, Lamine W, Li B, Sotiropoulos J, Chrostowska A, Miqueu K, Liu S. C−Boron Enolates Enable Palladium Catalyzed Carboboration of Internal 1,3‐Enynes. Angew Chem Int Ed Engl 2021. [DOI: 10.1002/ange.202108534] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Affiliation(s)
- Ziyong Wang
- Department of Chemistry Boston College Chestnut Hill MA 02467 USA
| | - Jason Wu
- Department of Chemistry Boston College Chestnut Hill MA 02467 USA
| | - Walid Lamine
- Université de Pau et des Pays de l'Adour, E2S UPPA CNRS, IPREM, UMR 5254 64053 Pau cedex 09 France
| | - Bo Li
- Department of Chemistry Boston College Chestnut Hill MA 02467 USA
| | - Jean‐Marc Sotiropoulos
- Université de Pau et des Pays de l'Adour, E2S UPPA CNRS, IPREM, UMR 5254 64053 Pau cedex 09 France
| | - Anna Chrostowska
- Université de Pau et des Pays de l'Adour, E2S UPPA CNRS, IPREM, UMR 5254 64053 Pau cedex 09 France
| | - Karinne Miqueu
- Université de Pau et des Pays de l'Adour, E2S UPPA CNRS, IPREM, UMR 5254 64053 Pau cedex 09 France
| | - Shih‐Yuan Liu
- Department of Chemistry Boston College Chestnut Hill MA 02467 USA
- Université de Pau et des Pays de l'Adour, E2S UPPA CNRS, IPREM, UMR 5254 64053 Pau cedex 09 France
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19
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Li S, Hu C, Cui X, Zhang J, Liu LL, Wu L. Site-Fixed Hydroboration of Terminal and Internal Alkenes using BX 3 / i Pr 2 NEt*. Angew Chem Int Ed Engl 2021; 60:26238-26245. [PMID: 34536251 DOI: 10.1002/anie.202111978] [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: 09/03/2021] [Indexed: 12/27/2022]
Abstract
An unprecedented and general hydroboration of alkenes with BX3 (X=Br, Cl) as the boration reagent in the presence of i Pr2 NEt is reported. The addition of i Pr2 NEt not only suppresses alkene polymerization and haloboration side reactions but also provides an "H" source for hydroboration. More importantly, the site-fixed installation of a boryl group at the original position of the internal double bond is readily achieved in contrast to conventional transition-metal-catalyzed hydroboration processes. Further application to the synthesis of 1,n-diborylalkanes (n=3-10) is also demonstrated. Preliminary mechanistic studies reveal a major reaction pathway that involves radical species and operates through a frustrated Lewis pair type single-electron-transfer mechanism.
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Affiliation(s)
- Sida Li
- State Key Laboratory for Oxo Synthesis and Selective Oxidation, Suzhou Research Institute of LICP, Lanzhou Institute of Chemical Physics (LICP), Chinese Academy of Sciences, Lanzhou, 730000, China.,University of Chinese Academy of Sciences, Beijing, 100049, China
| | - Chenyang Hu
- Shenzhen Grubbs Institute and Department of Chemistry, Southern University of Science and Technology, Shenzhen, 518055, China
| | - Xin Cui
- State Key Laboratory for Oxo Synthesis and Selective Oxidation, Suzhou Research Institute of LICP, Lanzhou Institute of Chemical Physics (LICP), Chinese Academy of Sciences, Lanzhou, 730000, China
| | - Jiong Zhang
- State Key Laboratory for Oxo Synthesis and Selective Oxidation, Suzhou Research Institute of LICP, Lanzhou Institute of Chemical Physics (LICP), Chinese Academy of Sciences, Lanzhou, 730000, China.,University of Chinese Academy of Sciences, Beijing, 100049, China
| | - Liu Leo Liu
- Shenzhen Grubbs Institute and Department of Chemistry, Southern University of Science and Technology, Shenzhen, 518055, China
| | - Lipeng Wu
- State Key Laboratory for Oxo Synthesis and Selective Oxidation, Suzhou Research Institute of LICP, Lanzhou Institute of Chemical Physics (LICP), Chinese Academy of Sciences, Lanzhou, 730000, China
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20
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Rej S, Das A, Chatani N. Pyrimidine-directed metal-free C-H borylation of 2-pyrimidylanilines: a useful process for tetra-coordinated triarylborane synthesis. Chem Sci 2021; 12:11447-11454. [PMID: 34567499 PMCID: PMC8409464 DOI: 10.1039/d1sc02937a] [Citation(s) in RCA: 12] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/31/2021] [Accepted: 07/22/2021] [Indexed: 12/15/2022] Open
Abstract
Convenient, easily handled, laboratory friendly, robust approaches to afford synthetically important organoboron compounds are currently of great interest to researchers. Among the various available strategies, a metal-free approach would be overwhelmingly accepted, since the target boron compounds can be prepared in a metal-free state. We herein present a detailed study of the metal-free directed ortho-C–H borylation of 2-pyrimidylaniline derivatives. The approach allowed us to synthesize various boronates, which are synthetically important compounds and various four-coordinated triarylborane derivatives, which could be useful in materials science as well as Lewis-acid catalysts. This metal-free directed C–H borylation reaction proceeds smoothly without any interference by external impurities, such as inorganic salts, reactive functionalities, heterocycles and even transition metal precursors, which further enhance its importance. We present the metal-free ortho-C–H borylation of 2-pyrimidylanilines to afford synthetically important boronic esters and tetra-coordinated triarylboranes, which could be useful in materials science as well as Lewis-acid catalysts.![]()
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Affiliation(s)
- Supriya Rej
- Department of Applied Chemistry, Faculty of Engineering, Osaka University Suita Osaka 5650871 Japan
| | - Amrita Das
- Department of Applied Chemistry, Faculty of Engineering, Osaka University Suita Osaka 5650871 Japan
| | - Naoto Chatani
- Department of Applied Chemistry, Faculty of Engineering, Osaka University Suita Osaka 5650871 Japan
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21
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Li Z, Sun J. Copper-Catalyzed 1,1-Boroalkylation of Terminal Alkynes: Access to Alkenylboronates via a Three-Component Reaction. Org Lett 2021; 23:3706-3711. [PMID: 33881877 DOI: 10.1021/acs.orglett.1c01081] [Citation(s) in RCA: 14] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/27/2023]
Abstract
A copper-catalyzed three-component reaction of terminal alkynes, diazo compounds, and B2pin2 to prepare trisubstituted alkenylboronates has been developed. This difunctionalization of alkynes selectively occurs at the terminal carbon atom and proceeds via a tandem sequence. The copper catalyst plays dual roles in the whole process, namely, the initial copper-catalyzed cross-coupling and the following copper-catalyzed stereoselective boration reaction. Typically, different carbene precursors selectively lead to Z- and E-alkenes.
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Affiliation(s)
- Ziyong Li
- Jiangsu Key Laboratory of Advanced Catalytic Materials & Technology, School of Petrochemical Engineering, Changzhou University, Changzhou 213164, P. R. China
| | - Jiangtao Sun
- Jiangsu Key Laboratory of Advanced Catalytic Materials & Technology, School of Petrochemical Engineering, Changzhou University, Changzhou 213164, P. R. China
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22
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Wu G, Pang B, Wang Y, Yan L, Chen L, Ma T, Ji Y. Metal-Free ortho-Selective C-H Borylation of 2-Phenylthiopyridines Using BBr 3. J Org Chem 2021; 86:5933-5942. [PMID: 33829798 DOI: 10.1021/acs.joc.1c00520] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
A novel route for ortho-selective C-H borylation of 2-phenylthiopyridines using BBr3 as the boron source under metal-free conditions has been reported. The reaction exhibited site exclusivity, and the synthesized aryl boronates were freely converted to various useful intermediates. Thus, this facile method would be beneficial to synthesize structurally diversified phenylthioethers derivatives and other materials containing boron-nitrogen coordination.
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Affiliation(s)
- Gaorong Wu
- Engineering Research Center of Pharmaceutical Process Chemistry, Ministry of Education; School of Pharmacy, East China University of Science and Technology, 130 Meilong Road, Shanghai 200237, People's Republic of China
| | - Binghan Pang
- Engineering Research Center of Pharmaceutical Process Chemistry, Ministry of Education; School of Pharmacy, East China University of Science and Technology, 130 Meilong Road, Shanghai 200237, People's Republic of China
| | - Yangyang Wang
- Engineering Research Center of Pharmaceutical Process Chemistry, Ministry of Education; School of Pharmacy, East China University of Science and Technology, 130 Meilong Road, Shanghai 200237, People's Republic of China
| | - Li Yan
- Analytical and Testing Center, Liangxiang Campus of Beijing Institute of Technology, Liangxiang East Road, Fangshan District, Beijing 102488, People's Republic of China
| | - Lu Chen
- Engineering Research Center of Pharmaceutical Process Chemistry, Ministry of Education; School of Pharmacy, East China University of Science and Technology, 130 Meilong Road, Shanghai 200237, People's Republic of China
| | - Tao Ma
- School of Chinese Materia Medica, Beijing University of Chinese Medicine, Liangxiang Campus, Fangshan District, Beijing 102488, People's Republic of China
| | - Yafei Ji
- Engineering Research Center of Pharmaceutical Process Chemistry, Ministry of Education; School of Pharmacy, East China University of Science and Technology, 130 Meilong Road, Shanghai 200237, People's Republic of China
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23
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Rej S, Chatani N. Transient Imine as a Directing Group for the Metal-Free o-C-H Borylation of Benzaldehydes. J Am Chem Soc 2021; 143:2920-2929. [PMID: 33586953 DOI: 10.1021/jacs.0c13013] [Citation(s) in RCA: 21] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/02/2023]
Abstract
Organoboron reagents are important synthetic intermediates and have wide applications in synthetic organic chemistry. The selective borylation strategies that are currently in use largely rely on the use of transition-metal catalysts. Hence, identifying much milder conditions for transition-metal-free borylation would be highly desirable. We herein present a unified strategy for the selective C-H borylation of electron-deficient benzaldehyde derivatives using a simple metal-free approach, utilizing an imine transient directing group. The strategy covers a wide spectrum of reactions and (i) even highly sterically hindered C-H bonds can be borylated smoothly, (ii) despite the presence of other potential directing groups, the reaction selectively occurs at the o-C-H bond of the benzaldehyde moiety, and (iii) natural products appended to benzaldehyde derivatives can also give the appropriate borylated products. Moreover, the efficacy of the protocol was confirmed by the fact that the reaction proceeds even in the presence of a series of external impurities.
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Affiliation(s)
- Supriya Rej
- Department of Applied Chemistry, Faculty of Engineering, Osaka University, Suita, Osaka 565-0871, Japan
| | - Naoto Chatani
- Department of Applied Chemistry, Faculty of Engineering, Osaka University, Suita, Osaka 565-0871, Japan
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24
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Mannisto JK, Pavlovic L, Tiainen T, Nieger M, Sahari A, Hopmann KH, Repo T. Mechanistic insights into carbamate formation from CO 2 and amines: the role of guanidine–CO 2 adducts. Catal Sci Technol 2021. [DOI: 10.1039/d1cy01433a] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/24/2023]
Abstract
This work explores the reactivity of a reversible superbase–CO2 zwitterion, which can be used as a stoichiometric source of CO2.
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Affiliation(s)
- Jere K. Mannisto
- Department of Chemistry, University of Helsinki, P.O. Box 55, A.I. Virtasen aukio 1, 00014 Helsinki, Finland
| | - Ljiljana Pavlovic
- Department of Chemistry, UiT The Arctic University of Norway, N-9037 Tromsø, Norway
| | - Tony Tiainen
- Department of Chemistry, University of Helsinki, P.O. Box 55, A.I. Virtasen aukio 1, 00014 Helsinki, Finland
| | - Martin Nieger
- Department of Chemistry, University of Helsinki, P.O. Box 55, A.I. Virtasen aukio 1, 00014 Helsinki, Finland
| | - Aleksi Sahari
- Department of Chemistry, University of Helsinki, P.O. Box 55, A.I. Virtasen aukio 1, 00014 Helsinki, Finland
| | - Kathrin H. Hopmann
- Department of Chemistry, UiT The Arctic University of Norway, N-9037 Tromsø, Norway
| | - Timo Repo
- Department of Chemistry, University of Helsinki, P.O. Box 55, A.I. Virtasen aukio 1, 00014 Helsinki, Finland
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25
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Iashin V, Berta D, Chernichenko K, Nieger M, Moslova K, Pápai I, Repo T. Metal-Free C-H Borylation of N-Heteroarenes by Boron Trifluoride. Chemistry 2020; 26:13873-13879. [PMID: 32478432 PMCID: PMC7702085 DOI: 10.1002/chem.202001436] [Citation(s) in RCA: 20] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/24/2020] [Revised: 05/28/2020] [Indexed: 01/08/2023]
Abstract
Organoboron compounds are essential reagents in modern C-C coupling reactions. Their synthesis via catalytic C-H borylation by main group elements is emerging as a powerful tool alternative to transition metal based catalysis. Herein, a straightforward metal-free synthesis of aryldifluoroboranes from BF3 and heteroarenes is reported. The reaction is assisted by sterically hindered amines and catalytic amounts of thioureas. According to computational studies the reaction proceeds via frustrated Lewis pair (FLP) mechanism. The obtained aryldifluoroboranes are further stabilized against destructive protodeborylation by converting them to the corresponding air stable tetramethylammonium organotrifluoroborates.
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Affiliation(s)
- Vladimir Iashin
- Department of ChemistryUniversity of HelsinkiA. I. Virtasen aukio, 100014HelsinkiFinland
| | - Dénes Berta
- Institute of Organic ChemistryResearch Centre for Natural SciencesMagyar tudósok körútja 21117BudapestHungary
| | - Konstantin Chernichenko
- Department of ChemistryUniversity of HelsinkiA. I. Virtasen aukio, 100014HelsinkiFinland
- Present address: API Small Molecule DevelopmentJanssen Pharmaceutica N.V.Turnhoutseweg 302340BeerseBelgium
| | - Martin Nieger
- Department of ChemistryUniversity of HelsinkiA. I. Virtasen aukio, 100014HelsinkiFinland
| | - Karina Moslova
- Department of ChemistryUniversity of HelsinkiA. I. Virtasen aukio, 100014HelsinkiFinland
| | - Imre Pápai
- Institute of Organic ChemistryResearch Centre for Natural SciencesMagyar tudósok körútja 21117BudapestHungary
| | - Timo Repo
- Department of ChemistryUniversity of HelsinkiA. I. Virtasen aukio, 100014HelsinkiFinland
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26
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Wu G, Fu X, Wang Y, Deng K, Zhang L, Ma T, Ji Y. C-H Borylation of Diphenylamines through Adamantane-1-carbonyl Auxiliary by BBr 3. Org Lett 2020; 22:7003-7007. [PMID: 32820932 DOI: 10.1021/acs.orglett.0c02552] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
A method for ortho-C-H borylation of diphenylamines using BBr3 as the boron source has been reported. The noncatalytic adamantane-1-carbonyl directed reaction exhibited site exclusivity and good functional group tolerance. Generally, the borylation occurred at the more electron-rich aromatic ring and the borylated products could be converted to various useful intermediates. Besides, the derived arylation and removal of auxiliary of the product could be achieved in a one-pot fashion.
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Affiliation(s)
- Gaorong Wu
- Engineering Research Centre of Pharmaceutical Process Chemistry, Ministry of Education; School of Pharmacy, East China University of Science and Technology, 130 Meilong Road, Shanghai 200237, P. R. China
| | - Xiaopan Fu
- Engineering Research Centre of Pharmaceutical Process Chemistry, Ministry of Education; School of Pharmacy, East China University of Science and Technology, 130 Meilong Road, Shanghai 200237, P. R. China
| | - Yangyang Wang
- Engineering Research Centre of Pharmaceutical Process Chemistry, Ministry of Education; School of Pharmacy, East China University of Science and Technology, 130 Meilong Road, Shanghai 200237, P. R. China
| | - Kezuan Deng
- Engineering Research Centre of Pharmaceutical Process Chemistry, Ministry of Education; School of Pharmacy, East China University of Science and Technology, 130 Meilong Road, Shanghai 200237, P. R. China
| | - Lili Zhang
- Engineering Research Centre of Pharmaceutical Process Chemistry, Ministry of Education; School of Pharmacy, East China University of Science and Technology, 130 Meilong Road, Shanghai 200237, P. R. China
| | - Tao Ma
- School of Chinese Materia Medica, Beijing University of Chinese Medicine, Liangxiang Campus, Fangshan District, Beijing 102488, P. R. China
| | - Yafei Ji
- Engineering Research Centre of Pharmaceutical Process Chemistry, Ministry of Education; School of Pharmacy, East China University of Science and Technology, 130 Meilong Road, Shanghai 200237, P. R. China
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27
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Zhu D, Gan S, Bao RLY, Shi L. Copper-catalyzed cross-coupling of vinyliodonium salts and diboron reagents to generate alkenyl boronic esters. Org Biomol Chem 2020; 18:5567-5570. [PMID: 32662488 DOI: 10.1039/d0ob01121e] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
An efficient approach for the synthesis of alkenyl boronic esters through the copper-catalyzed cross-coupling of vinyliodonium salts and diboron reagents is reported. This method is distinguished by its mild conditions and short reaction time of less than 30 min, which should provide an additional way for the construction of alkenyl boronic esters.
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Affiliation(s)
- Dan Zhu
- School of Science, Harbin Institute of Technology, Shenzhen, 518055, China.
| | - Shaoyan Gan
- School of Science, Harbin Institute of Technology, Shenzhen, 518055, China.
| | - Robert Li-Yuan Bao
- School of Science, Harbin Institute of Technology, Shenzhen, 518055, China.
| | - Lei Shi
- School of Science, Harbin Institute of Technology, Shenzhen, 518055, China.
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28
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Gioia B, Arnaud A, Radix S, Walchshofer N, Doléans-Jordheim A, Rocheblave L. Spectral data for the synthesis of ( E)-alkenylboronic acid pinacol esters via hydroboration of alkynes. Data Brief 2020; 30:105354. [PMID: 32258264 PMCID: PMC7109635 DOI: 10.1016/j.dib.2020.105354] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/17/2020] [Accepted: 02/24/2020] [Indexed: 11/26/2022] Open
Abstract
This data article is related to a research paper entitled “Solvent- and metal-free hydroboration of alkynes under microwave irradiation” (Gioia et al. TETL-D-19-01698) [1]. Herein we present the spectral data acquired from the synthesis of (E)-alkenyl boronic acid pinacol esters. The data include the general information and the synthetic procedure affording the target derivatives, which were fully characterized by Nuclear Magnetic Resonance (1H and 13C NMR) and, for the most part, by Electrospray Ionization High Resolution Mass (ESI-MS). Proton and carbon NMR spectra and ESI-MS spectra were provided which will be useful for further organic chemists if they are interested in the synthesis of these building blocks.
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Affiliation(s)
- Bruna Gioia
- Univ Lyon, Université Claude Bernard Lyon 1, ISPB-Faculté de Pharmacie, EA 4446, B2MC, F-69373, Lyon Cedex 08, France
| | - Alexandre Arnaud
- Univ Lyon, Université Claude Bernard Lyon 1, ISPB-Faculté de Pharmacie, EA 4446, B2MC, F-69373, Lyon Cedex 08, France
| | - Sylvie Radix
- Univ Lyon, Université Claude Bernard Lyon 1, ISPB-Faculté de Pharmacie, EA 4446, B2MC, F-69373, Lyon Cedex 08, France
| | - Nadia Walchshofer
- Univ Lyon, Université Claude Bernard Lyon 1, ISPB-Faculté de Pharmacie, EA 4446, B2MC, F-69373, Lyon Cedex 08, France
| | - Anne Doléans-Jordheim
- Univ Lyon, Université Claude Bernard Lyon 1, VetAgro Sup, UMR CNRS 5557, Ecologie Microbienne, F-69622, Villeurbanne, France.,Laboratoire de Bactériologie, Centre de Biologie et Pathologie Est, Hospices Civils de Lyon (HCL), F-69000, Bron, France
| | - Luc Rocheblave
- Univ Lyon, Université Claude Bernard Lyon 1, ISPB-Faculté de Pharmacie, EA 4446, B2MC, F-69373, Lyon Cedex 08, France
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29
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Iqbal SA, Cid J, Procter RJ, Uzelac M, Yuan K, Ingleson MJ. Acyl-Directed ortho-Borylation of Anilines and C7 Borylation of Indoles using just BBr 3. Angew Chem Int Ed Engl 2019; 58:15381-15385. [PMID: 31461213 PMCID: PMC6856876 DOI: 10.1002/anie.201909786] [Citation(s) in RCA: 80] [Impact Index Per Article: 16.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/02/2019] [Indexed: 01/04/2023]
Abstract
Indoles are privileged heterocycles found in many biologically active pharmaceuticals and natural products. However, the selective functionalization of the benzenoid moiety in indoles in preference to the more reactive pyrrolic unit is a significant challenge. Herein we report that N-acyl directing groups enable the C7-selective C-H borylation of indoles using just BBr3 . This transformation shows some functional-group tolerance and notably proceeds with C6 substituted indoles. The directing group can be readily removed in situ and the products isolated as the pinacol boronate esters. Acyl-directed electrophilic borylation can be extended to carbazoles and anilines with excellent ortho selectivity. 4-amino-indoles are amenable to this process, with acyl group installation and directed electrophilic C-H borylation enabling selective formation of C5-BPin-indoles.
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Affiliation(s)
- Saqib A. Iqbal
- School of ChemistryUniversity of EdinburghEdinburghEH9 3FJUK
| | - Jessica Cid
- Dept. of ChemistryUniversity of ManchesterManchesterM13 9PLUK
| | | | - Marina Uzelac
- School of ChemistryUniversity of EdinburghEdinburghEH9 3FJUK
| | - Kang Yuan
- School of ChemistryUniversity of EdinburghEdinburghEH9 3FJUK
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30
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Tanaka S, Kunisawa T, Yoshii Y, Hattori T. Acylation of Alkenes with the Aid of AlCl3 and 2,6-Dibromopyridine. Org Lett 2019; 21:8509-8513. [DOI: 10.1021/acs.orglett.9b02688] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Affiliation(s)
- Shinya Tanaka
- Department of Biomolecular Engineering, Graduate School of Engineering, Tohoku University, 6-6-11 Aramaki-Aoba, Aoba-ku, Sendai 980-8579, Japan
- Environment Conservation Center, Tohoku University, 6-6-04 Aramaki-Aoba, Aoba-ku, Sendai 980-8579, Japan
| | - Tsukasa Kunisawa
- Department of Biomolecular Engineering, Graduate School of Engineering, Tohoku University, 6-6-11 Aramaki-Aoba, Aoba-ku, Sendai 980-8579, Japan
| | - Yuji Yoshii
- Department of Biomolecular Engineering, Graduate School of Engineering, Tohoku University, 6-6-11 Aramaki-Aoba, Aoba-ku, Sendai 980-8579, Japan
| | - Tetsutaro Hattori
- Department of Biomolecular Engineering, Graduate School of Engineering, Tohoku University, 6-6-11 Aramaki-Aoba, Aoba-ku, Sendai 980-8579, Japan
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31
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Čubiňák M, Edlová T, Polák P, Tobrman T. Indolylboronic Acids: Preparation and Applications. Molecules 2019; 24:E3523. [PMID: 31569441 PMCID: PMC6803883 DOI: 10.3390/molecules24193523] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/07/2019] [Revised: 09/24/2019] [Accepted: 09/25/2019] [Indexed: 11/16/2022] Open
Abstract
Indole derivatives are associated with a variety of both biological activities and applications in the field of material chemistry. A number of different strategies for synthesizing substituted indoles by means of the reactions of indolylboronic acids with electrophilic compounds are considered the methods of choice for modifying indoles because indolylboronic acids are easily available, stable, non-toxic and new reactions using indolylboronic acids have been described in the literature. Thus, the aim of this review is to summarize the methods available for the preparation of indolylboronic acids as well as their chemical transformations. The review covers the period 2010-2019.
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Affiliation(s)
- Marek Čubiňák
- Department of Organic Chemistry, University of Chemistry and Technology Prague, Technická 5, 166 28 Prague 6, Czech Republic.
| | - Tereza Edlová
- Department of Organic Chemistry, University of Chemistry and Technology Prague, Technická 5, 166 28 Prague 6, Czech Republic.
| | - Peter Polák
- Department of Organic Chemistry, University of Chemistry and Technology Prague, Technická 5, 166 28 Prague 6, Czech Republic.
| | - Tomáš Tobrman
- Department of Organic Chemistry, University of Chemistry and Technology Prague, Technická 5, 166 28 Prague 6, Czech Republic.
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32
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Iqbal SA, Cid J, Procter RJ, Uzelac M, Yuan K, Ingleson MJ. Acyl‐Directed
ortho
‐Borylation of Anilines and C7 Borylation of Indoles using just BBr
3. Angew Chem Int Ed Engl 2019. [DOI: 10.1002/ange.201909786] [Citation(s) in RCA: 17] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/07/2023]
Affiliation(s)
- Saqib A. Iqbal
- School of Chemistry University of Edinburgh Edinburgh EH9 3FJ UK
| | - Jessica Cid
- Dept. of Chemistry University of Manchester Manchester M13 9PL UK
| | | | - Marina Uzelac
- School of Chemistry University of Edinburgh Edinburgh EH9 3FJ UK
| | - Kang Yuan
- School of Chemistry University of Edinburgh Edinburgh EH9 3FJ UK
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33
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Li K, Yu S, Zhuo K, Lu X, Xiao B, Gong T, Fu Y. Synthesis of Conjugated Boron‐Enynes
via cis‐
Alkynylboration of Terminal Alkynes. Adv Synth Catal 2019. [DOI: 10.1002/adsc.201900294] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
Affiliation(s)
- Kuan Li
- Hefei National Laboratory for Physical Sciences at the Microscale, CAS Key Laboratory of Urban Pollutant Conversion, Anhui Province Key Laboratory of Biomass Clean Energy, iChEM University of Science and Technology of China Hefei 230026 People's Republic of China
| | - Shang‐Hai Yu
- Hefei National Laboratory for Physical Sciences at the Microscale, CAS Key Laboratory of Urban Pollutant Conversion, Anhui Province Key Laboratory of Biomass Clean Energy, iChEM University of Science and Technology of China Hefei 230026 People's Republic of China
| | - Kai‐Feng Zhuo
- Hefei National Laboratory for Physical Sciences at the Microscale, CAS Key Laboratory of Urban Pollutant Conversion, Anhui Province Key Laboratory of Biomass Clean Energy, iChEM University of Science and Technology of China Hefei 230026 People's Republic of China
| | - Xi Lu
- Hefei National Laboratory for Physical Sciences at the Microscale, CAS Key Laboratory of Urban Pollutant Conversion, Anhui Province Key Laboratory of Biomass Clean Energy, iChEM University of Science and Technology of China Hefei 230026 People's Republic of China
| | - Bin Xiao
- Hefei National Laboratory for Physical Sciences at the Microscale, CAS Key Laboratory of Urban Pollutant Conversion, Anhui Province Key Laboratory of Biomass Clean Energy, iChEM University of Science and Technology of China Hefei 230026 People's Republic of China
| | - Tian‐Jun Gong
- Hefei National Laboratory for Physical Sciences at the Microscale, CAS Key Laboratory of Urban Pollutant Conversion, Anhui Province Key Laboratory of Biomass Clean Energy, iChEM University of Science and Technology of China Hefei 230026 People's Republic of China
| | - Yao Fu
- Hefei National Laboratory for Physical Sciences at the Microscale, CAS Key Laboratory of Urban Pollutant Conversion, Anhui Province Key Laboratory of Biomass Clean Energy, iChEM University of Science and Technology of China Hefei 230026 People's Republic of China
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34
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Nguyen VD, Nguyen VT, Jin S, Dang HT, Larionov OV. Organoboron chemistry comes to light: recent advances in photoinduced synthetic approaches to organoboron compounds. Tetrahedron 2019; 75:584-602. [PMID: 31564756 PMCID: PMC6764765 DOI: 10.1016/j.tet.2018.12.040] [Citation(s) in RCA: 25] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/09/2023]
Abstract
Photoinduced synthetic approaches to organoboron compounds have attracted significant attention in the recent years. Photochemical activation of organic molecules enables generation of reactive intermediates from a variety of precursors, resulting in borylation methods with improved and broader substrate scopes. The review summarizes recent developments in the area of photoinduced reactions of organoboron compounds with an emphasis on borylation of haloarenes, amine derivatives, and redox-active esters of carboxylic acids, as well as photoinduced rearrangements of organoboron compounds and photoinduced synthesis of organoboron compounds from alkenes and alkynes.
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Affiliation(s)
- Viet D Nguyen
- Department of Chemistry, The University of Texas at San Antonio, San Antonio, TX 78249, USA
| | - Vu T Nguyen
- Department of Chemistry, The University of Texas at San Antonio, San Antonio, TX 78249, USA
| | - Shengfei Jin
- Department of Chemistry, The University of Texas at San Antonio, San Antonio, TX 78249, USA
| | - Hang T Dang
- Department of Chemistry, The University of Texas at San Antonio, San Antonio, TX 78249, USA
| | - Oleg V Larionov
- Department of Chemistry, The University of Texas at San Antonio, San Antonio, TX 78249, USA
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35
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Lu W, Shen Z. Direct Synthesis of Alkenylboronates from Alkenes and Pinacol Diboron via Copper Catalysis. Org Lett 2018; 21:142-146. [DOI: 10.1021/acs.orglett.8b03599] [Citation(s) in RCA: 24] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Wenkui Lu
- Shanghai Key Laboratory for Molecular Engineering of Chiral Drugs, School of Chemistry and Chemical Engineering, Shanghai Jiao Tong University, 800 Dongchuan Road, Shanghai, 200240, China
| | - Zengming Shen
- Shanghai Key Laboratory for Molecular Engineering of Chiral Drugs, School of Chemistry and Chemical Engineering, Shanghai Jiao Tong University, 800 Dongchuan Road, Shanghai, 200240, China
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36
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Reid WB, Watson DA. Synthesis of Trisubstituted Alkenyl Boronic Esters from Alkenes Using the Boryl-Heck Reaction. Org Lett 2018; 20:6832-6835. [PMID: 30350673 PMCID: PMC6388719 DOI: 10.1021/acs.orglett.8b02949] [Citation(s) in RCA: 24] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/30/2023]
Abstract
The direct borylation of disubstituted alkenes is reported. These conditions allow for the conversion of a variety 1,1- and 1,2-disubstituted alkenes to trisubstituted alkenyl boronic esters with outstanding yields and excellent E/ Z selectivities. The utility of this reaction has been demonstrated with several downstream functionalization reactions, which allow access to diverse, stereodefined, functionalized olefins. Mechanistic studies are consistent with a boryl-Heck pathway.
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Affiliation(s)
- William B Reid
- Department of Chemistry and Biochemistry , University of Delaware , Newark , Delaware 19716 , United States
| | - Donald A Watson
- Department of Chemistry and Biochemistry , University of Delaware , Newark , Delaware 19716 , United States
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