1
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Zahara AJ, Haines BE, Wilkerson-Hill SM. Programmed Heterocycle Synthesis Using Halomucononitriles as Pyridinimine Precursors. Org Lett 2024; 26:2976-2981. [PMID: 38557087 DOI: 10.1021/acs.orglett.4c00547] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 04/04/2024]
Abstract
Herein we report a method to convert primary amines, ubiquitous motifs found in pharmaceutical libraries, to either imidazo[1,2-a]pyridines or 7-alkyl azaindoles in two steps from known compounds. Using halomucononitrile reagents, we can directly access 5-bromo-6-imino-1-alkyl-1,6-dihydropyridine-2-carbonitriles (pyridinimines) in a single step from primary amines (25-93% yield) through the cyclization of transient aminomucononitrile intermediates. We then demonstrate that these compounds can be readily converted to 7-alkylazaindoles using Sonogashira cross-coupling conditions (13 examples, up to 91% yield). Under oxidative conditions, the pyridinimines serve as directing groups for C-H functionalization reactions to afford imidazo[1,2-a]pyridines. We also studied the mechanism of the cyclization event using DFT calculations and propose that this takes place via sequential base-mediated E/Z isomerization and cyclization steps.
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Affiliation(s)
- Adam J Zahara
- Department of Chemistry, The University of North Carolina at Chapel Hill, Chapel Hill, North Carolina 27599, United States
| | - Brandon E Haines
- Department of Chemistry, Westmont College, Santa Barbara, California 93108, United States
| | - Sidney M Wilkerson-Hill
- Department of Chemistry, The University of North Carolina at Chapel Hill, Chapel Hill, North Carolina 27599, United States
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2
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Yadav N, Bhatta SR, Moorthy JN. Visible Light-Induced Decomposition of Acyl Peroxides Using Isocyanides: Synthesis of Heteroarenes by Radical Cascade Cyclization. J Org Chem 2023; 88:5431-5439. [PMID: 37093050 DOI: 10.1021/acs.joc.2c03059] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 04/25/2023]
Abstract
Visible light-mediated facile synthesis of heteroarenes, namely, isoquinolines, benzothiazoles, and quinazolines, is demonstrated by employing isocyanides and inexpensive acyl peroxides. It is shown for the first time that singlet-excited isocyanides decompose acyl peroxides into aryl/alkyl radicals. The latter attack isocyanides, yielding imidoyl radicals that subsequently cyclize to afford heteroarene products. The protocol involving radical cascade reactions obviates the requirement of any external photocatalyst, oxidant, additive, and base.
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Affiliation(s)
- Navin Yadav
- Department of Chemistry, Indian Institute of Technology, Kanpur, Uttar Pradesh 208016, India
| | - Sushil Ranjan Bhatta
- Department of Chemistry, Indian Institute of Technology, Kanpur, Uttar Pradesh 208016, India
| | - Jarugu Narasimha Moorthy
- Department of Chemistry, Indian Institute of Technology, Kanpur, Uttar Pradesh 208016, India
- School of Chemistry, Indian Institute of Science Education and Research, Thiruvananthapuram 695551, India
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3
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Li K, Li Q, Shi Q, He Y, Yu W, Chang J. Iodine‐Mediated sp3 C–H Amination Reactions Forming α‐Amino Ketones/Esters and Fused Imidazoles. ASIAN J ORG CHEM 2022. [DOI: 10.1002/ajoc.202200268] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Affiliation(s)
- Kailu Li
- Zhengzhou University College of Chemistry CHINA
| | - Qianmin Li
- Zhengzhou University College of Chemistry CHINA
| | - Qinhao Shi
- Zhengzhou University College of Chemistry CHINA
| | - Yanmin He
- Zhengzhou University College of Chemistry CHINA
| | - Wenquan Yu
- Zhengzhou University College of Chemistry 100 Science Avenue 450001 Zhengzhou CHINA
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4
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Prusinowski AF, Sise HC, Bednar TN, Nagib DA. Radical Aza-Heck Cyclization of Imidates via Energy Transfer, Electron Transfer, and Cobalt Catalysis. ACS Catal 2022; 12:4327-4332. [PMID: 35479099 PMCID: PMC9038135 DOI: 10.1021/acscatal.2c00804] [Citation(s) in RCA: 12] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
A radical aza-Heck cyclization has been developed to afford functionally rich products with four contiguous C-heteroatom bonds. This multi-catalytic strategy provides rapid syntheses of dense, medicinally relevant motifs by enabling the conversion of alcohol-derived imidates to heteroatom-rich fragments containing vinyl oxazolines/oxazoles, allyl amines, β-amino alcohols/halides, and combinations thereof. Mechanistic insights of this process show how three distinct photocatalytic cycles cooperate to enable: (1) imidate radical generation by energy transfer, (2) dehydrogenation by Co catalysis, and (3) catalyst turnover by electron transfer.
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Affiliation(s)
- Allen F. Prusinowski
- Department of Chemistry and Biochemistry, The Ohio State University, Columbus, Ohio 43210, United States
| | - Henry C. Sise
- Department of Chemistry and Biochemistry, The Ohio State University, Columbus, Ohio 43210, United States
| | - Taylor N. Bednar
- Department of Chemistry and Biochemistry, The Ohio State University, Columbus, Ohio 43210, United States
| | - David A. Nagib
- Department of Chemistry and Biochemistry, The Ohio State University, Columbus, Ohio 43210, United States
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5
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Mou XQ, Ren LC, Zhang M, Wang M, Jin YF, Guan QX, Cai A, Zhang SM, Ren H, Zhang Y, Chen YZ. Complementary Copper-Catalyzed and Electrochemical Aminosulfonylation of O-Homoallyl Benzimidates and N-Alkenyl Amidines with Sodium Sulfinates. Org Lett 2022; 24:1405-1411. [PMID: 35138858 DOI: 10.1021/acs.orglett.2c00287] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
Abstract
A complementary copper-catalyzed and electrochemical aminosulfonylation of O-homoallyl benzimidates and N-alkenyl amidines with sodium sulfinates was developed. The terminal alkene substrate produced sulfone-containing 1,3-oxazines and tetrahydropyrimidines in the presence of Cu(OAc)2, Ag2CO3, and DPP, and under similar reaction conditions, sulfonylated tetrahydro-1,3-oxazepines were prepared from 1-aryl-substituted O-homoallyl benzimidates in moderate to good yields. For certain electron-rich 1,1-diaryl-substituted alkene substrates, the corresponding tetrahydro-1,3-oxazepines could also be obtained in similar or even higher yields via a green electrochemical technique.
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Affiliation(s)
- Xue-Qing Mou
- Key Laboratory of Biocatalysis & Chiral Drug Synthesis of Guizhou Province, Key Laboratory of Basic Pharmacology of Ministry of Education and Joint International Research Laboratory of Ethnomedicine of Ministry of Education, School of Pharmacy, Zunyi Medical University, Zunyi 563003, P. R. China
| | - Liang-Chen Ren
- Key Laboratory of Biocatalysis & Chiral Drug Synthesis of Guizhou Province, Key Laboratory of Basic Pharmacology of Ministry of Education and Joint International Research Laboratory of Ethnomedicine of Ministry of Education, School of Pharmacy, Zunyi Medical University, Zunyi 563003, P. R. China
| | - Mei Zhang
- Key Laboratory of Biocatalysis & Chiral Drug Synthesis of Guizhou Province, Key Laboratory of Basic Pharmacology of Ministry of Education and Joint International Research Laboratory of Ethnomedicine of Ministry of Education, School of Pharmacy, Zunyi Medical University, Zunyi 563003, P. R. China
| | - Min Wang
- Key Laboratory of Biocatalysis & Chiral Drug Synthesis of Guizhou Province, Key Laboratory of Basic Pharmacology of Ministry of Education and Joint International Research Laboratory of Ethnomedicine of Ministry of Education, School of Pharmacy, Zunyi Medical University, Zunyi 563003, P. R. China
| | - Yu-Fan Jin
- Key Laboratory of Biocatalysis & Chiral Drug Synthesis of Guizhou Province, Key Laboratory of Basic Pharmacology of Ministry of Education and Joint International Research Laboratory of Ethnomedicine of Ministry of Education, School of Pharmacy, Zunyi Medical University, Zunyi 563003, P. R. China
| | - Qing-Xin Guan
- Key Laboratory of Biocatalysis & Chiral Drug Synthesis of Guizhou Province, Key Laboratory of Basic Pharmacology of Ministry of Education and Joint International Research Laboratory of Ethnomedicine of Ministry of Education, School of Pharmacy, Zunyi Medical University, Zunyi 563003, P. R. China
| | - Ang Cai
- Key Laboratory of Biocatalysis & Chiral Drug Synthesis of Guizhou Province, Key Laboratory of Basic Pharmacology of Ministry of Education and Joint International Research Laboratory of Ethnomedicine of Ministry of Education, School of Pharmacy, Zunyi Medical University, Zunyi 563003, P. R. China
| | - Shi-Min Zhang
- Key Laboratory of Biocatalysis & Chiral Drug Synthesis of Guizhou Province, Key Laboratory of Basic Pharmacology of Ministry of Education and Joint International Research Laboratory of Ethnomedicine of Ministry of Education, School of Pharmacy, Zunyi Medical University, Zunyi 563003, P. R. China
| | - Hai Ren
- State Key Laboratory of Functions and Applications of Medicinal Plants, Guizhou Medical University, Guiyang 550014, China
| | - Yun Zhang
- Key Laboratory of Biocatalysis & Chiral Drug Synthesis of Guizhou Province, Key Laboratory of Basic Pharmacology of Ministry of Education and Joint International Research Laboratory of Ethnomedicine of Ministry of Education, School of Pharmacy, Zunyi Medical University, Zunyi 563003, P. R. China
| | - Yong-Zheng Chen
- Key Laboratory of Biocatalysis & Chiral Drug Synthesis of Guizhou Province, Key Laboratory of Basic Pharmacology of Ministry of Education and Joint International Research Laboratory of Ethnomedicine of Ministry of Education, School of Pharmacy, Zunyi Medical University, Zunyi 563003, P. R. China
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6
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Xi JM, Sun YH, Li WC, Wu YH, Wei ZL, Liao WW. Radical Alkene-Trifluoromethylation-Triggered Nitrile Insertion/Remote Functionalization Relay Processes: Diverse Synthesis of Trifluoromethylated Azaheterocycles Enabled by Copper Catalysis. Org Lett 2022; 24:1110-1115. [PMID: 35080394 DOI: 10.1021/acs.orglett.2c00083] [Citation(s) in RCA: 10] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
A copper-catalyzed alkene-trifluoromethylation-triggered nitrile insertion/remote functionalization relay process has been achieved, in which "interrupted" remote 1,n-difunctionalizations of alkenes with nitrile insertion can deliver iminyl radical intermediates instead of C-based radicals, followed by subsequent 1,n-HAT to furnish corresponding remote functionalization. This relay protocol enables a straightforward approach to streamline the assembly of structurally diverse trifluoromethylated azaheterocycles.
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Affiliation(s)
- Ji-Ming Xi
- Department of Organic Chemistry, College of Chemistry, Jilin University, 2699 Qianjin Street, Changchun 130012, P. R. China
| | - Yun-Hai Sun
- Department of Organic Chemistry, College of Chemistry, Jilin University, 2699 Qianjin Street, Changchun 130012, P. R. China
| | - Wen-Cheng Li
- Department of Organic Chemistry, College of Chemistry, Jilin University, 2699 Qianjin Street, Changchun 130012, P. R. China
| | - Yu-Heng Wu
- Department of Organic Chemistry, College of Chemistry, Jilin University, 2699 Qianjin Street, Changchun 130012, P. R. China
| | - Zhong-Lin Wei
- Department of Organic Chemistry, College of Chemistry, Jilin University, 2699 Qianjin Street, Changchun 130012, P. R. China
| | - Wei-Wei Liao
- Department of Organic Chemistry, College of Chemistry, Jilin University, 2699 Qianjin Street, Changchun 130012, P. R. China.,State Key Laboratory of Organometallic Chemistry, Shanghai Institute of Organic Chemistry, Chinese Academy of Sciences, Shanghai 200032, P. R. China
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7
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Li Z, Wu YH, Xi JM, Wei ZL, Liao WW. Copper-Catalyzed Difluoroalkylation of Alkene/Nitrile Insertion/Cyclization Tandem Sequences: Construction of Difluorinated Bicyclic Amidines. Org Lett 2021; 23:9591-9596. [PMID: 34874172 DOI: 10.1021/acs.orglett.1c03802] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/08/2023]
Abstract
A copper-catalyzed difluoroalkylation of an alkene/nitrile insertion/cyclization tandem sequence of N-cyanamide alkene was described, which provided a convenient synthetic approach for accessing difluorinated bicyclic amidines bearing imine moieties in a sustainable fashion. This protocol is characterized by high yields, a broad substrate scope, and good functional group compatibility. In addition, the desired product can be readily converted into other valuable functionalized fluorinated aza-heterocycles.
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Affiliation(s)
- Zheng Li
- Department of Organic Chemistry, College of Chemistry, Jilin University, 2699 Qianjin Street, Changchun 130012, P. R. China
| | - Yu-Heng Wu
- Department of Organic Chemistry, College of Chemistry, Jilin University, 2699 Qianjin Street, Changchun 130012, P. R. China
| | - Ji-Ming Xi
- Department of Organic Chemistry, College of Chemistry, Jilin University, 2699 Qianjin Street, Changchun 130012, P. R. China
| | - Zhong-Lin Wei
- Department of Organic Chemistry, College of Chemistry, Jilin University, 2699 Qianjin Street, Changchun 130012, P. R. China
| | - Wei-Wei Liao
- Department of Organic Chemistry, College of Chemistry, Jilin University, 2699 Qianjin Street, Changchun 130012, P. R. China.,State Key Laboratory of Organometallic Chemistry, Shanghai Institute of Organic Chemistry, Chinese Academy of Sciences, Shanghai 200032, P. R. China
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8
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Neha K, Ali F, Haider K, Khasimbi S, Wakode S. Synthetic approaches for oxazole derivatives: A review. SYNTHETIC COMMUN 2021. [DOI: 10.1080/00397911.2021.1986843] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/20/2022]
Affiliation(s)
- Kumari Neha
- Department of Pharmaceutical Chemistry, Delhi Institute of Pharmaceutical Sciences and Research (DIPSAR), DPSRU, New Delhi, India
| | - Faraat Ali
- Department of Inspection and Enforcement, Laboratory services, Botswana Medicines Regulatory Authority, Gaborone, Botswana
| | - Kashif Haider
- Department of Pharmaceutical Chemistry, School of Pharmaceutical Education and Research, Jamia Hamdard (Deemed to be University), New Delhi, India
| | - Shaik Khasimbi
- Department of Pharmaceutical Chemistry, Delhi Institute of Pharmaceutical Sciences and Research (DIPSAR), DPSRU, New Delhi, India
| | - Sharad Wakode
- Department of Pharmaceutical Chemistry, Delhi Institute of Pharmaceutical Sciences and Research (DIPSAR), DPSRU, New Delhi, India
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9
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Wu D, Cui SS, Bian F, Yu W. Visible Light Driven and Copper-Catalyzed C(sp 3)-H Functionalization of O-Pentafluorobenzoyl Ketone Oximes. Org Lett 2021; 23:6057-6061. [PMID: 34279963 DOI: 10.1021/acs.orglett.1c02133] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022]
Abstract
The C(sp3)-H functionalization of O-pentafluorobenzoyl ketone oximes was implemented under visible light irradiation with copper complexes as catalysts. The reactions involve iminyl-radical-mediated intramolecular hydrogen atom transfer as the key step, with the iminyl radicals being generated via copper-effected N-O cleavage. The reaction afforded 3,4-dihydro-2H-pyrroles under the conditions of [Cu(DPEphos)(bcp)]PF6 and DABCO, while γ-pentafluorobenzoyloxy ketones were produced predominantly when [Cu(dpp)2]PF6 and InCl3·4H2O were used as catalysts.
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Affiliation(s)
- Danhua Wu
- College of Chemistry and Chemical Engineering, Lanzhou University, Lanzhou, Gansu 730000, China
| | - Shuang-Shuang Cui
- College of Chemistry and Chemical Engineering, Lanzhou University, Lanzhou, Gansu 730000, China
| | - Fengling Bian
- College of Chemistry and Chemical Engineering, Lanzhou University, Lanzhou, Gansu 730000, China
| | - Wei Yu
- State Key Laboratory of Applied Organic Chemistry, College of Chemistry and Chemical Engineering, Lanzhou, Gansu 73000, China
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10
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Zhang Z, Ngo DT, Nagib DA. Regioselective Radical Amino-Functionalizations of Allyl Alcohols via Dual Catalytic Cross-Coupling. ACS Catal 2021; 11:3473-3477. [PMID: 34745713 DOI: 10.1021/acscatal.1c00404] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
The regioselective amination and cross-coupling of a range of nucleophiles with allyl alcohols has been enabled by a dual catalytic strategy. This approach entails the combined action of an Ir photocatalyst that enables mild access to N-radicals via an energy transfer mechanism, as well as a Cu complex that intercepts the ensuing alkyl radical upon cyclization. Merger of this Cu-catalyzed cross-coupling enables a broad range of nucleophiles (e.g. CN, SCN, N3, vinyl, allyl) to engage in radical amino-functionalizations of olefins. Notably, stereo, regio, and kinetic probes provide insights into the nature of this Cu-based radical interception.
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Affiliation(s)
- Zuxiao Zhang
- Department of Chemistry and Biochemistry, The Ohio State University, Columbus, Ohio 43210, United States
| | - Duong T. Ngo
- Department of Chemistry and Biochemistry, The Ohio State University, Columbus, Ohio 43210, United States
| | - David A. Nagib
- Department of Chemistry and Biochemistry, The Ohio State University, Columbus, Ohio 43210, United States
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11
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Zhang H, Sun MC, Yin LM, Wei D, Song MP, Yang D, Niu JL. Direct intramolecular C(sp 3)–H bond sulfonamidation to synthesize benzosultam derivatives under metal-free conditions. Org Chem Front 2021. [DOI: 10.1039/d1qo01235e] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022]
Abstract
An efficient intramolecular C(sp3)–H bond amination under metal-free conditions has been developed to provide a straightforward method for the synthesis of 5-membered cyclic sulfonamides (benzosultams).
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Affiliation(s)
- He Zhang
- Green Catalysis Center, and College of Chemistry, Zhengzhou University, Zhengzhou 450001, P. R. China
| | - Meng-Chan Sun
- Green Catalysis Center, and College of Chemistry, Zhengzhou University, Zhengzhou 450001, P. R. China
| | - Li-Ming Yin
- Green Catalysis Center, and College of Chemistry, Zhengzhou University, Zhengzhou 450001, P. R. China
| | - Donghui Wei
- Green Catalysis Center, and College of Chemistry, Zhengzhou University, Zhengzhou 450001, P. R. China
| | - Mao-Ping Song
- Green Catalysis Center, and College of Chemistry, Zhengzhou University, Zhengzhou 450001, P. R. China
| | - Dandan Yang
- Green Catalysis Center, and College of Chemistry, Zhengzhou University, Zhengzhou 450001, P. R. China
| | - Jun-Long Niu
- Green Catalysis Center, and College of Chemistry, Zhengzhou University, Zhengzhou 450001, P. R. China
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12
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Mukku N, Madivalappa Davanagere P, Chanda K, Maiti B. A Facile Microwave-Assisted Synthesis of Oxazoles and Diastereoselective Oxazolines Using Aryl-Aldehydes, p-Toluenesulfonylmethyl Isocyanide under Controlled Basic Conditions. ACS OMEGA 2020; 5:28239-28248. [PMID: 33163807 PMCID: PMC7643254 DOI: 10.1021/acsomega.0c04130] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 08/26/2020] [Accepted: 10/06/2020] [Indexed: 06/11/2023]
Abstract
In this study, a highly efficient two-component [3 + 2] cycloaddition reaction of substituted aryl aldehydes with 4-toluenesulfonylmethyl isocyanide (TosMIC) in the presence of 2 equiv of potassium phosphate as a base to 5-substituted oxazoles were established in a isopropanol medium under microwave irradiation. However, using 1 equiv of K3PO4 as a base resulted in the diastereoselective synthesis of 4,5-disubstituted oxazolines under identical reaction conditions. The foremost benefits of these protocols are the moderate-to-excellent yields with good functional group compatibility, simple experimental procedure, inexpensive readily available starting materials, nonchromatographic purification, and high bond-forming efficiency. The synthetic manipulation reported herein represents a cleaner route to the sustainable preparation of 5-substituted oxazoles and diastereoselective 4,5-disubstituted oxazolines derivatives.
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Affiliation(s)
- Narasimharao Mukku
- Department of Chemistry,
School of Advanced Sciences, Vellore Institute
of Technology, Vellore 632014, India
| | | | - Kaushik Chanda
- Department of Chemistry,
School of Advanced Sciences, Vellore Institute
of Technology, Vellore 632014, India
| | - Barnali Maiti
- Department of Chemistry,
School of Advanced Sciences, Vellore Institute
of Technology, Vellore 632014, India
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13
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Saito A, Togo H. Photochemical Transformation of O
-(β-Arylethyl) Arylimidates into 2,4-Diaryl-5-iodoxazoles with 1,3-Diiodo-5,5-dimethylhydantoin. European J Org Chem 2020. [DOI: 10.1002/ejoc.202000383] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/25/2023]
Affiliation(s)
- Aya Saito
- Graduate School of Science; Chiba University; Yayoi-cho 1-33 263-8522 Chiba Inage-ku Japan
| | - Hideo Togo
- Graduate School of Science; Chiba University; Yayoi-cho 1-33 263-8522 Chiba Inage-ku Japan
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14
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Prusinowski AF, Twumasi RK, Wappes EA, Nagib DA. Vicinal, Double C-H Functionalization of Alcohols via an Imidate Radical-Polar Crossover Cascade. J Am Chem Soc 2020; 142:5429-5438. [PMID: 32141741 PMCID: PMC7299201 DOI: 10.1021/jacs.0c01318] [Citation(s) in RCA: 34] [Impact Index Per Article: 8.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
A double functionalization of vicinal sp3 C-H bonds has been developed, wherein a β amine and γ iodide are incorporated onto an aliphatic alcohol in a single operation. This approach is enabled by an imidate radical chaperone, which selectively affords a transient β alkene that is amino-iodinated in situ. Overall, the radical-polar-crossover cascade entails the following key steps: (i) β C-H iodination via 1,5-hydrogen atom transfer (HAT), (ii) desaturation via I2 complexation, and (iii) vicinal amino-iodination of an in situ generated allyl imidate. The synthetic utility of this double C-H functionalization is illustrated by conversion of aliphatic alcohols to a diverse collection of α,β,γ substituted products bearing heteroatoms on three adjacent carbons. The radical-polar crossover mechanism is supported by various experimental probes, including isotopic labeling, intermediate validation, and kinetic studies.
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Affiliation(s)
- Allen F Prusinowski
- Department of Chemistry and Biochemistry, The Ohio State University, Columbus, Ohio 43210, United States
| | - Raymond K Twumasi
- Department of Chemistry and Biochemistry, The Ohio State University, Columbus, Ohio 43210, United States
| | - Ethan A Wappes
- Department of Chemistry and Biochemistry, The Ohio State University, Columbus, Ohio 43210, United States
| | - David A Nagib
- Department of Chemistry and Biochemistry, The Ohio State University, Columbus, Ohio 43210, United States
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