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Regioselective C-H sulfenylation of N-sulfonyl protected 7-azaindoles promoted by TBAI: a rapid synthesis of 3-thio-7-azaindoles.

ABSTRACT: This paper describes the regioselective C-3 sulfenylation of N-sulfonyl protected 7-azaindoles with sulfonyl chlorides. In this transformation, dual roles of TBAI serving as both promoter and desulfonylation reagent have been demonstrated. The reaction proceeded smoothly under simple conditions to afford 3-thio-7-azaindoles in moderate to good yields with broad substrate scopes. This protocol refrains from using transition-metal catalysts, strong oxidants or bases, and shows its practical synthetic value in organic synthesis.

SUBMITTER: Hu J

PROVIDER: S-EPMC9056539 | biostudies-literature | 2020 Aug

REPOSITORIES: biostudies-literature

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Regioselective C-H sulfenylation of N-sulfonyl protected 7-azaindoles promoted by TBAI: a rapid synthesis of 3-thio-7-azaindoles.

Hu Jingyan J Ji Xiaoming X Hao Shuai S Zhao Mingqin M Lai Miao M Ren Tianbao T Xi Gaolei G Wang Erbin E Wang Juanjuan J Wu Zhiyong Z

RSC advances 20200827 53

This paper describes the regioselective C-3 sulfenylation of N-sulfonyl protected 7-azaindoles with sulfonyl chlorides. In this transformation, dual roles of TBAI serving as both promoter and desulfonylation reagent have been demonstrated. The reaction proceeded smoothly under simple conditions to afford 3-thio-7-azaindoles in moderate to good yields with broad substrate scopes. This protocol refrains from using transition-metal catalysts, strong oxidants or bases, and shows its practical ...[more]

PMID: 35518137

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