Visible-light promoted aerobic difunctionalization of alkenes with sulfonyl hydrazides for the synthesis of β-keto/hydroxyl sulfones

A practical method has been developed for the conversion of alkenes to -keto/hydroxyl sulfones by their reaction with sulfonyl hydrazides under metal-free conditions. This reaction proceeds through the oxidative addition of alkenes by sulfonyl radicals that are generated by visible-light induced oxidation of sulfonyl hydrazides. Notaly the reaction uses O-2 as the terminal oxidant, instead of metal catalysts or oxidants like TBHP, leading to H2O and N-2 as the clean by-products. The key features of this reaction include readily available reagents, mild reaction conditions and broad substrate scope.