Synthesis of Isothiochroman-3-ones via Metal-Free Oxidative Cyclization of Alkynyl Thioethers.

Org Lett

iChEM, State Key Laboratory of Physical Chemistry of Solid Surfaces and Key Laboratory for Chemical Biology of Fujian Province, College of Chemistry and Chemical Engineering , Xiamen University, Xiamen 361005 , China.

Published: December 2018

A novel Brønsted acid-catalyzed oxidative C-H functionalization of alkynyl thioethers has been developed. This method allows the practical synthesis of valuable isothiochroman-3-ones in mostly moderate to good yields under mild reaction conditions and features a broad substrate scope and wide functional group tolerance. Moreover, this metal-free oxidation can also be used to promote formal N-H insertion involving an unexpected 1,2-sulfur migration, affording useful 1,4-benzothiazin-3-ones.

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http://dx.doi.org/10.1021/acs.orglett.8b03462DOI Listing

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