Multicomponent reactions to access S-aryl dithiocarbamates via an electron donor–acceptor complex under open-to-air conditions

Abstract

A simple and efficient transition-metal/photocatalyst-free visible-light-driven one-pot three-component reaction between thianthrenium salts, carbon disulfide and amines under an air atmosphere for the preparation of biologically relevant S-aryl dithiocarbamates is developed. This methodology is robust and scalable, and exhibits a broad substrate scope and excellent functional group tolerance. Of note, a wide range of primary aliphatic amines bearing different groups are suitable for this strategy. The synthetic utility was further demonstrated by a two-step one-pot multi-component reaction and photo-flow decagram-scale synthesis. Preliminary mechanistic studies suggest that the association of the dithiocarbamate anion with thianthrenium salts formed an electron donor–acceptor complex, which upon excitation with visible light produced an aryl radical via single-electron transfer.