Visible-Light Induced Sulfonylation of Baylis-Hillman Acetates under Metal- and Oxidant-free Conditions

A metal-free and oxidant-free procedure for the sulfonylation of Baylis-Hillman acetates with sulfonyl hydrazides under the irradiation of visible light under open-air conditions at room temperature was described. This transformation has high yields (up to 92%), excellent stereoselectivity, broad substrate scope, good functional group tolerance, and mild reaction conditions. Moreover, the mechanistic studies indicated that a sulfonyl radical pathway was involved in this reaction.