Synthesis 2019; 51(20): 3859-3864
DOI: 10.1055/s-0037-1611895
paper
© Georg Thieme Verlag Stuttgart · New York

Aryl Ketone Mediated Photoinduced Radical Coupling for the Alkylation­ of Benzazoles Employing Saturated Heterocyclic Compounds­

Shin Kamijo
Graduate School of Sciences and Technology for Innovation, Yamaguchi University, Yamaguchi 753-8512, Japan   Email: kamijo@yamaguchi-u.ac.jp
,
Kaori Kamijo
,
Toshihiro Murafuji
› Author Affiliations
This research was supported by a research grant from the Astellas Foundation for Research on Metabolic Disorders, a program of the YU Project for Formation of the Core Research Center, and the Japan Society for the Promotion of Science (JSPS, KAKENHI Grant Number JP18K05107).
Further Information

Publication History

Received: 12 May 2019

Accepted after revision: 01 July 2019

Publication Date:
31 July 2019 (online)


Abstract

An aryl ketone mediated synthesis of 2-alkylated benzazoles was achieved via radical coupling under photoirradiation starting from saturated heterocycles and 2-sulfonylated benzazoles, such as benzothiazoles, benzoxazole, and benzimidazole. Heterocyclic compounds, including a cyclic ether, azacycles, and tetrahydrothiophene, were applicable, and the benzazole unit was site-selectively installed at the carbon center proximal to the heteroatom. The present transformation takes place at ambient temperature under neutral reaction conditions without the aid of any metallic catalysts or reagents.

Supporting Information

 
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