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The involvement of the trisulfur radical anion in electron-catalyzed sulfur insertion reactions: facile synthesis of benzothiazine derivatives under transition metal-free conditions.

ABSTRACT: An efficient and practical synthesis of benzothiazine by K₂S initiated sulfur insertion reaction with enaminones via electron catalysis is developed. This protocol provides a new, environment-friendly and simple strategy to construct benzothiazine derivatives via formation of two C-S bonds under transition metal-free, additive-free and oxidant-free conditions. K₂S not only provides the sulfur insertion source, but also ignites the reaction through the formation of a trisulfur radical anion and electrons in DMF.

SUBMITTER: Gu ZY

PROVIDER: S-EPMC6013918 | biostudies-literature |

REPOSITORIES: biostudies-literature

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