Synlett 2019; 30(14): 1648-1655
DOI: 10.1055/s-0039-1690107
cluster
© Georg Thieme Verlag Stuttgart · New York

Photocatalytic Oxidative C–H Thiolation: Synthesis of Benzothiazoles and Sulfenylated Indoles

Andrew N. Dinh ‡
,
Ashley D. Nguyen ‡
,
Ernesto Millan Aceves
,
Samuel T. Albright
,
Mario R. Cedano
,
Diane K. Smith
,
Jeffrey L. Gustafson∗
This work was supported by the National Science Foundation (Grant No. Che-1664565).
Further Information

Publication History

Received: 24 April 2019

Accepted after revision: 17 June 2019

Publication Date:
27 June 2019 (online)

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‡ Both authors contributed equally

Published as part of the Cluster for Organosulfur and Organo­selenium Compounds in Catalysis

Abstract

We report studies on the photocatalytic formation of C–S bonds to form benzothiazoles via an intramolecular cyclization and sulfenylated indoles via an intermolecular reaction. Cyclic voltammetry (CV) and density functional theory studies suggest that benzothiazole formation proceeds via a mechanism that involves an electrophilic sulfur radical, while the indole sulfenylation likely proceeds via a nucleophilic sulfur radical adding into a radical cationic indole. These conditions were successfully extended to several thiobenzamides and indole substrates.

Key words

photoredox catalysis - benzothiazole - indole - thiolation - C–H functionalization

Supporting Information

    Supporting information for this article is available online at https://doi.org/10.1055/s-0039-1690107.
  • Supporting Information
 

  • References and Notes

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