Synthesis of donor/acceptor-substituted diazo compounds in flow and their application in enantioselective dirhodium-catalyzed cyclopropanation and C？H functionalization

Abstract

A tandem reaction system has been developed for the preparation of donor/acceptor-substituted diazo compounds in continuous flow coupled to dirhodiumcatalyzed C？H functionalization or cyclopropanation. Hydrazones were oxidized in flow by solid-supported N-iodo-ptoluenesulfonamide potassium salt (PS-SO2NIK) to generate the diazo compounds, which were then purified by passing through a column of molecular sieves/sodium thiosulfate.