Photocatalyst-free visible-light-induced cross-dehydrogenative sulfenylation of aminocoumarins and amino-1,4-naphthoquinones

Abstract

A photocatalyst-free strategy has been developed for the cross-dehydrogenative sulfenylation of aminocoumarins with thiols. A library of sulfenylated aminocoumarins has been synthesized using this protocol under the irradiation of blue LED light. This protocol is also useful for the sulfenylation of aminopyranones and amino-1,4-naphthoquinones. The photocatalytic activation of persulfate is the key step in this transformation. Simple and easy execution, excellent yields, practical applicability, photocatalyst-free conditions and column chromatography-free purification of sulfenylated aminocoumarins are the attractive features of this methodology.