1
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Groslambert L, Pale P, Mamane V. Telluronium-Catalyzed Halogenation Reactions: Chalcogen-Bond Activation of N-Halosuccinimides and Catalysis. Chemistry 2024:e202401650. [PMID: 38785097 DOI: 10.1002/chem.202401650] [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: 04/26/2024] [Revised: 05/16/2024] [Accepted: 05/24/2024] [Indexed: 05/25/2024]
Abstract
The ability of triaryltelluronium salts to interact with N-halosuccinimides (NXS) through chalcogen bonding (ChB) in the solid state and in solution is demonstrated herein. Cocrystals of the triaryltelluronium bearing two CF3 electron-withdrawing groups per aryl ring with N-chloro-, N-bromo- and N-iodosuccinimide (respectively NCS, NBS and NIS) were analyzed by X-ray diffraction, evidencing a ChB between tellurium and the carbonyl group of NXS. This ChB was confirmed in solution by NMR spectroscopy, especially by 125Te NMR titration experiment, which allowed the determination of the association constant (Ka) between the telluronium and NBS. The so-obtained Ka value of 17.3±0.6 M-1 indicated a moderate interaction in solution because of the competitive role of the solvent. The strength of the Te⋅⋅⋅O ChB was however sufficient enough to promote the catalytic halofunctionalization of aromatics and of alkenes such as the intra- and intermolecular haloalkoxylation and haloesterification of alkenes.
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Affiliation(s)
- Loic Groslambert
- Institute of Chemistry of Strasbourg, UMR 7177, CNRS and Strasbourg University, 4 rue Blaise Pascal, 67000, Strasbourg, France
| | - Patrick Pale
- Institute of Chemistry of Strasbourg, UMR 7177, CNRS and Strasbourg University, 4 rue Blaise Pascal, 67000, Strasbourg, France
| | - Victor Mamane
- Institute of Chemistry of Strasbourg, UMR 7177, CNRS and Strasbourg University, 4 rue Blaise Pascal, 67000, Strasbourg, France
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2
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Matsuoka J, Yano Y, Hirose Y, Mashiba K, Sawada N, Nakamura A, Maegawa T. Elemental Sulfur-Mediated Aromatic Halogenation. J Org Chem 2024; 89:770-777. [PMID: 38113515 DOI: 10.1021/acs.joc.3c02259] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2023]
Abstract
A method for aromatic halogenation using a combination of elemental sulfur (S8) and N-halosuccinimide has been developed. A catalytic quantity of elemental sulfur (S8) with N-bromosuccinimide (NBS) and N-chlorosuccinimide (NCS) effectively halogenated less-reactive aromatic compounds, such as ester-, cyano-, and nitro-substituted anisole derivatives. No reaction occurred in the absence of S8, underscoring its crucial role in the catalytic activity. This catalytic system was also applicable to aromatic iodination with 1,3-diiodo-5,5-dimethylhydantoin.
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Affiliation(s)
- Junpei Matsuoka
- School of Pharmaceutical Sciences, Kindai University, Higashi-Osaka, Osaka 577-8502, Japan
| | - Yuna Yano
- School of Pharmaceutical Sciences, Kindai University, Higashi-Osaka, Osaka 577-8502, Japan
| | - Yuuka Hirose
- School of Pharmaceutical Sciences, Kindai University, Higashi-Osaka, Osaka 577-8502, Japan
| | - Koushi Mashiba
- School of Pharmaceutical Sciences, Kindai University, Higashi-Osaka, Osaka 577-8502, Japan
| | - Nanako Sawada
- School of Pharmaceutical Sciences, Kindai University, Higashi-Osaka, Osaka 577-8502, Japan
| | - Akira Nakamura
- School of Pharmaceutical Sciences, Kindai University, Higashi-Osaka, Osaka 577-8502, Japan
| | - Tomohiro Maegawa
- School of Pharmaceutical Sciences, Kindai University, Higashi-Osaka, Osaka 577-8502, Japan
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3
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Motiwala HF, Armaly AM, Cacioppo JG, Coombs TC, Koehn KRK, Norwood VM, Aubé J. HFIP in Organic Synthesis. Chem Rev 2022; 122:12544-12747. [PMID: 35848353 DOI: 10.1021/acs.chemrev.1c00749] [Citation(s) in RCA: 108] [Impact Index Per Article: 54.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
1,1,1,3,3,3-Hexafluoroisopropanol (HFIP) is a polar, strongly hydrogen bond-donating solvent that has found numerous uses in organic synthesis due to its ability to stabilize ionic species, transfer protons, and engage in a range of other intermolecular interactions. The use of this solvent has exponentially increased in the past decade and has become a solvent of choice in some areas, such as C-H functionalization chemistry. In this review, following a brief history of HFIP in organic synthesis and an overview of its physical properties, literature examples of organic reactions using HFIP as a solvent or an additive are presented, emphasizing the effect of solvent of each reaction.
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Affiliation(s)
- Hashim F Motiwala
- Divison of Chemical Biology and Medicinal Chemistry, UNC Eshelman School of Pharmacy, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina 27599 United States
| | - Ahlam M Armaly
- Divison of Chemical Biology and Medicinal Chemistry, UNC Eshelman School of Pharmacy, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina 27599 United States
| | - Jackson G Cacioppo
- Divison of Chemical Biology and Medicinal Chemistry, UNC Eshelman School of Pharmacy, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina 27599 United States
| | - Thomas C Coombs
- Department of Chemistry, University of North Carolina Wilmington, Wilmington, North Carolina 28403 United States
| | - Kimberly R K Koehn
- Divison of Chemical Biology and Medicinal Chemistry, UNC Eshelman School of Pharmacy, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina 27599 United States
| | - Verrill M Norwood
- Divison of Chemical Biology and Medicinal Chemistry, UNC Eshelman School of Pharmacy, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina 27599 United States
| | - Jeffrey Aubé
- Divison of Chemical Biology and Medicinal Chemistry, UNC Eshelman School of Pharmacy, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina 27599 United States
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4
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Baker SI, Yaghoubi M, Bidwell SL, Pierce SL, Hratchian HP, Baxter RD. Enhanced Reactivity for Aromatic Bromination via Halogen Bonding with Lactic Acid Derivatives. J Org Chem 2022; 87:8492-8502. [PMID: 35709498 DOI: 10.1021/acs.joc.2c00611] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
We report a new method for regioselective aromatic bromination using lactic acid derivatives as halogen bond acceptors with N-bromosuccinimide (NBS). Several structural analogues of lactic acid affect the efficiency of aromatic brominations, presumably via Lewis acid/base halogen-bonding interactions. Rate comparisons of aromatic brominations demonstrate the reactivity enhancement available via catalytic additives capable of halogen bonding. Computational results demonstrate that Lewis basic additives interact with NBS to increase the electropositive character of bromine prior to electrophilic transfer. An optimized procedure using catalytic mandelic acid under aqueous conditions at room temperature was developed to promote aromatic bromination on a variety of arene substrates with complete regioselectivity.
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Affiliation(s)
- Sarah I Baker
- Department of Chemistry and Biochemistry, University of California, 5200 N. Lake Road, Merced, California 95343, United States
| | - Mahshid Yaghoubi
- Department of Chemistry and Biochemistry, University of California, 5200 N. Lake Road, Merced, California 95343, United States
| | - Samantha L Bidwell
- Department of Chemistry and Biochemistry, University of California, 5200 N. Lake Road, Merced, California 95343, United States
| | - Savannah L Pierce
- Department of Chemistry and Biochemistry, University of California, 5200 N. Lake Road, Merced, California 95343, United States
| | - Hrant P Hratchian
- Department of Chemistry and Biochemistry, University of California, 5200 N. Lake Road, Merced, California 95343, United States
| | - Ryan D Baxter
- Department of Chemistry and Biochemistry, University of California, 5200 N. Lake Road, Merced, California 95343, United States
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5
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Xu H, Hu L, Zhu G, Zhu Y, Wang Y, Wu ZG, Zi Y, Huang W. DABCO as a practical catalyst for aromatic halogenation with N-halosuccinimides. RSC Adv 2022; 12:7115-7119. [PMID: 35424677 PMCID: PMC8982236 DOI: 10.1039/d2ra00197g] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/11/2022] [Accepted: 02/23/2022] [Indexed: 11/21/2022] Open
Abstract
A simple and practical synthetic approach for synthesis of aromatic halides is developed. Simple Lewis base, DABCO, is used as the catalyst. This arene halogenation process proceedes conveniently and efficiently at ambient conditions, providing the desired products in good to excellent yields and selectivity.
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Affiliation(s)
- Haiyan Xu
- Nantong Normal College Nantong 226010 Jiangsu P. R. China
| | - Lanping Hu
- School of Chemistry and Chemical Engineering, Nantong University Nantong 226019 Jiangsu P. R. China
| | - Guanghua Zhu
- School of Chemistry and Chemical Engineering, Nantong University Nantong 226019 Jiangsu P. R. China
| | - Yueping Zhu
- Nantong Normal College Nantong 226010 Jiangsu P. R. China
| | - Yang Wang
- School of Chemistry and Chemical Engineering, Nantong University Nantong 226019 Jiangsu P. R. China
| | - Zheng-Guang Wu
- School of Chemistry and Chemical Engineering, Nantong University Nantong 226019 Jiangsu P. R. China
| | - You Zi
- School of Chemistry and Chemical Engineering, Nantong University Nantong 226019 Jiangsu P. R. China
| | - Weichun Huang
- School of Chemistry and Chemical Engineering, Nantong University Nantong 226019 Jiangsu P. R. China
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6
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Lorpaiboon W, Bovonsombat P. Halogen bond-induced electrophilic aromatic halogenations. Org Biomol Chem 2021; 19:7518-7534. [PMID: 34346463 DOI: 10.1039/d1ob00936b] [Citation(s) in RCA: 19] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
In recent years, there has been increasing interest in utilising halogen bonds in organic synthesis, especially in aromatic halogenation reactions. N-Halosuccinimides and 1,3-dihalo-5,5-dimethylhydantoins are popular sources of halonium ions due to their ease of handling and low toxicities. Traditionally, these N-haloimides are activated by electrophiles, namely Brønsted and Lewis acids. The recent discovery of possible activation by nucleophilic Lewis base catalysts led to a paradigm shift in aromatic halogenation. Active functional motifs in Lewis base catalysts such as CS, R-S-R1, Ar-S-S-Ar, SO, Ar-NH2, and R2NH+Cl- form halogen bonds with the positively charged σ-hole of the halogen atoms: an essential interaction to produce halonium ions. This review highlights the evolution of the two modes of activation. Evidence of halogen bond formation from mechanistic studies of nucleophilic activation is also discussed herein.
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Affiliation(s)
- Wanutcha Lorpaiboon
- Mahidol University International College, Mahidol University, Salaya, Nakorn Pathom 73170, Thailand.
| | - Pakorn Bovonsombat
- Mahidol University International College, Mahidol University, Salaya, Nakorn Pathom 73170, Thailand.
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7
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Activator free, expeditious and eco-friendly chlorination of activated arenes by N-chloro-N-(phenylsulfonyl)benzene sulfonamide (NCBSI). Tetrahedron Lett 2021. [DOI: 10.1016/j.tetlet.2020.152689] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022]
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8
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Dinh AN, Maddox SM, Vaidya SD, Saputra MA, Nalbandian CJ, Gustafson JL. Catalyst-Controlled Regioselective Chlorination of Phenols and Anilines through a Lewis Basic Selenoether Catalyst. J Org Chem 2020; 85:13895-13905. [PMID: 33044067 DOI: 10.1021/acs.joc.0c01917] [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
We report a highly efficient ortho-selective electrophilic chlorination of phenols utilizing a Lewis basic selenoether catalyst. The selenoether catalyst resulted in comparable selectivities to our previously reported bis-thiourea ortho-selective catalyst, with a catalyst loading as low as 1%. The new catalytic system also allowed us to extend this chemistry to obtain excellent ortho-selectivities for unprotected anilines. The selectivities of this reaction are up to >20:1 ortho/para, while the innate selectivities for phenols and anilines are approximately 1:4 ortho/para. A series of preliminary studies revealed that the substrates require a hydrogen-bonding moiety for selectivity.
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Affiliation(s)
- Andrew N Dinh
- Department of Chemistry and Biochemistry, San Diego State University, San Diego, California 92182, United States
| | - Sean M Maddox
- Department of Chemistry and Biochemistry, San Diego State University, San Diego, California 92182, United States
| | - Sagar D Vaidya
- Department of Chemistry and Biochemistry, San Diego State University, San Diego, California 92182, United States
| | - Mirza A Saputra
- Department of Chemistry and Biochemistry, San Diego State University, San Diego, California 92182, United States
| | - Christopher J Nalbandian
- Department of Chemistry and Biochemistry, San Diego State University, San Diego, California 92182, United States
| | - Jeffrey L Gustafson
- Department of Chemistry and Biochemistry, San Diego State University, San Diego, California 92182, United States
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9
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Qu Z, Zhu H, Grimme S. Mechanistic Insights for Aniline‐Catalyzed Halogenation Reactions. ChemCatChem 2020. [DOI: 10.1002/cctc.202000981] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
Affiliation(s)
- Zheng‐Wang Qu
- Mulliken Center for Theoretical Chemistry University of Bonn Beringstr. 4 53115 Bonn Germany
| | - Hui Zhu
- Mulliken Center for Theoretical Chemistry University of Bonn Beringstr. 4 53115 Bonn Germany
| | - Stefan Grimme
- Mulliken Center for Theoretical Chemistry University of Bonn Beringstr. 4 53115 Bonn Germany
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10
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Dhakal R, Li X, Parkin SR, Lehmler HJ. Synthesis of mono- and dimethoxylated polychlorinated biphenyl derivatives starting from fluoroarene derivatives. ENVIRONMENTAL SCIENCE AND POLLUTION RESEARCH INTERNATIONAL 2020; 27:8905-8925. [PMID: 31893358 PMCID: PMC7098850 DOI: 10.1007/s11356-019-07133-3] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/13/2019] [Accepted: 11/20/2019] [Indexed: 06/10/2023]
Abstract
Polychlorinated biphenyls (PCBs) are environmental pollutants implicated in a variety of adverse health effects, including cancer and noncancer diseases in animals and humans. PCBs are metabolized to hydroxylated compounds, and some of these PCB metabolites are more toxic than the parent PCBs. Unfortunately, most PCB metabolites needed for toxicological studies are not available from commercial sources. Moreover, it is challenging to synthesize PCB metabolites because starting materials with suitable substitution patterns are not readily available. Here, we report the novel synthesis of a variety of mono- and dimethoxyarene derivatives from commercially available fluoroarenes via nucleophilic aromatic substitution with sodium methoxide. This reaction provided good to excellent yields of the desired methoxylated products. Suzuki coupling of selected mono- and dimethoxy haloarenes with chlorinated phenylboronic acids yielded methoxylated derivatives of PCB 11, 12, 25, 35, and 36 in low to good yields. Crystal structures of 3,3'-dichloro-2,5-dimethoxy-1,1'-biphenyl and 3',5-dichloro-2,3-dimethoxy-1,1'-biphenyl confirmed the substitution pattern of both compounds. This synthesis strategy provides straightforward access to a range of mono- and dimethoxylated PCB derivatives that were not readily accessible previously.
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Affiliation(s)
- Ram Dhakal
- Department of Occupational and Environmental Health, College of Public Health, The University of Iowa, University of Iowa Research Park, #221 IREH, Iowa City, IA, 52242, USA
| | - Xueshu Li
- Department of Occupational and Environmental Health, College of Public Health, The University of Iowa, University of Iowa Research Park, #221 IREH, Iowa City, IA, 52242, USA
| | - Sean R Parkin
- Department of Chemistry, University of Kentucky, Lexington, KY, 40506, USA
| | - Hans-Joachim Lehmler
- Department of Occupational and Environmental Health, College of Public Health, The University of Iowa, University of Iowa Research Park, #221 IREH, Iowa City, IA, 52242, USA.
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11
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Nishii Y, Ikeda M, Hayashi Y, Kawauchi S, Miura M. Triptycenyl Sulfide: A Practical and Active Catalyst for Electrophilic Aromatic Halogenation Using N-Halosuccinimides. J Am Chem Soc 2020; 142:1621-1629. [PMID: 31868360 DOI: 10.1021/jacs.9b12672] [Citation(s) in RCA: 62] [Impact Index Per Article: 15.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
A Lewis base catalyst Trip-SMe (Trip = triptycenyl) for electrophilic aromatic halogenation using N-halosuccinimides (NXS) is introduced. In the presence of an appropriate activator (as a noncoordinating-anion source), a series of unactivated aromatic compounds were halogenated at ambient temperature using NXS. This catalytic system was applicable to transformations that are currently unachievable except for the use of Br2 or Cl2: e.g., multihalogenation of naphthalene, regioselective bromination of BINOL, etc. Controlled experiments revealed that the triptycenyl substituent exerts a crucial role for the catalytic activity, and kinetic experiments implied the occurrence of a sulfonium salt [Trip-S(Me)Br][SbF6] as an active species. Compared to simple dialkyl sulfides, Trip-SMe exhibited a significant charge-separated ion pair character within the halonium complex whose structural information was obtained by the single-crystal X-ray analysis. A preliminary computational study disclosed that the π system of the triptycenyl functionality is a key motif to consolidate the enhancement of electrophilicity.
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Affiliation(s)
- Yuji Nishii
- Frontier Research Base for Global Young Researchers, Graduate School of Engineering , Osaka University , Suita , Osaka 565-0871 , Japan
| | - Mitsuhiro Ikeda
- Department of Applied Chemistry, Graduate School of Engineering , Osaka University , Suita , Osaka 565-0871 , Japan
| | - Yoshihiro Hayashi
- Department of Chemical Science and Engineering, School of Materials and Chemical Technology , Tokyo Institute of Technology , 2-12-1-E4-6 Ookayama , Meguro-ku , Tokyo 152-8552 , Japan
| | - Susumu Kawauchi
- Department of Chemical Science and Engineering, School of Materials and Chemical Technology , Tokyo Institute of Technology , 2-12-1-E4-6 Ookayama , Meguro-ku , Tokyo 152-8552 , Japan
| | - Masahiro Miura
- Department of Applied Chemistry, Graduate School of Engineering , Osaka University , Suita , Osaka 565-0871 , Japan
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12
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Bovonsombat P, Stone S, Rossi M, Caruso F. Halogen bonds in N-bromosuccinimide and other N-halosuccinimides. Struct Chem 2019. [DOI: 10.1007/s11224-019-01321-0] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
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13
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Xiong X, Yeung YY. Ammonium Salt-Catalyzed Highly Practical Ortho-Selective Monohalogenation and Phenylselenation of Phenols: Scope and Applications. ACS Catal 2018. [DOI: 10.1021/acscatal.8b00327] [Citation(s) in RCA: 54] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
Affiliation(s)
- Xiaodong Xiong
- Department of Chemistry, The Chinese University of Hong Kong, Shatin, NT, Hong Kong (China)
| | - Ying-Yeung Yeung
- Department of Chemistry, The Chinese University of Hong Kong, Shatin, NT, Hong Kong (China)
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14
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Tang RJ, Milcent T, Crousse B. Regioselective Halogenation of Arenes and Heterocycles in Hexafluoroisopropanol. J Org Chem 2018; 83:930-938. [DOI: 10.1021/acs.joc.7b02920] [Citation(s) in RCA: 85] [Impact Index Per Article: 14.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Affiliation(s)
- Ren-Jin Tang
- Faculty of Pharmacy, UMR
8076, BioCIS, Univ. Paris-Sud-CNRS, Université Paris-Saclay, 92290 Châtenay-Malabry, France
| | - Thierry Milcent
- Faculty of Pharmacy, UMR
8076, BioCIS, Univ. Paris-Sud-CNRS, Université Paris-Saclay, 92290 Châtenay-Malabry, France
| | - Benoit Crousse
- Faculty of Pharmacy, UMR
8076, BioCIS, Univ. Paris-Sud-CNRS, Université Paris-Saclay, 92290 Châtenay-Malabry, France
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15
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Bovonsombat P, Teecomegaet P, Kulvaranon P, Pandey A, Chobtumskul K, Tungsirisurp S, Sophanpanichkul P, Losuwanakul S, Soimaneewan D, Kanjanwongpaisan P, Siricharoensang P, Choosakoonkriang S. Regioselective monobromination of aromatics via a halogen bond acceptor-donor interaction of catalytic thioamide and N-bromosuccinimide. Tetrahedron 2017. [DOI: 10.1016/j.tet.2017.10.005] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
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16
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Wang C, Wang Z, Wang L, Chen Q, He M. Catalytic Thiourea Promoted Electrophilic Thiocyanation of Indoles and Aromatic Amines with NCS/NH4SCN. CHINESE J CHEM 2016. [DOI: 10.1002/cjoc.201600344] [Citation(s) in RCA: 29] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
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17
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Maddox SM, Dinh AN, Armenta F, Um J, Gustafson JL. The Catalyst-Controlled Regiodivergent Chlorination of Phenols. Org Lett 2016; 18:5476-5479. [DOI: 10.1021/acs.orglett.6b02650] [Citation(s) in RCA: 44] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/25/2023]
Affiliation(s)
- Sean M. Maddox
- Department
of Chemistry and Biochemistry, San Diego State University, 5500
Campanile Drive, San Diego, California 92182, United States
| | - Andrew N. Dinh
- Department
of Chemistry and Biochemistry, San Diego State University, 5500
Campanile Drive, San Diego, California 92182, United States
| | - Felipe Armenta
- Department
of Chemistry and Biochemistry, San Diego State University, 5500
Campanile Drive, San Diego, California 92182, United States
| | - Joann Um
- Department
of Physical Sciences, Southwestern College, 900 Otay Lakes Road, Chula Vista, California 91910, United States
| | - Jeffrey L. Gustafson
- Department
of Chemistry and Biochemistry, San Diego State University, 5500
Campanile Drive, San Diego, California 92182, United States
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18
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Cheng YA, Yu WZ, Yeung YY. An unexpected Bromolactamization of Olefinic Amides Using a Three-Component Co-catalyst System. J Org Chem 2015; 81:545-52. [PMID: 26679219 DOI: 10.1021/acs.joc.5b02390] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/14/2023]
Abstract
Reaction between (N,N-dimethylamino)pyridine and isocyanate unexpectedly produced a three-component mixture. By using this mixture as an unprecedented three-component catalyst system, a facile and selective bromolactamization of olefinic amides has been developed. The protocol confers enhanced selectivity of N- over O-cyclization, leading to the formation of a structurally diverse range of lactams including both small and medium ring sizes.
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Affiliation(s)
- Yi An Cheng
- Department of Chemistry, National University of Singapore , 3 Science Drive 3, Singapore 117543
| | - Wesley Zongrong Yu
- Department of Chemistry, National University of Singapore , 3 Science Drive 3, Singapore 117543
| | - Ying-Yeung Yeung
- Department of Chemistry, The Chinese University of Hong Kong , Shatin, NT, Hong Kong, China.,Department of Chemistry, National University of Singapore , 3 Science Drive 3, Singapore 117543
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