A Copper-Catalyzed Three-Component Reaction of Triethoxysilanes, Sulfur Dioxide, and Hydrazines

A three-component reaction of triethoxysilanes, sulfur dioxide, and hydrazines catalyzed by copper(II) acetate is reported, leading to N-aminosulfonamides in good yields. Not only triethoxy(aryl)silanes but also triethoxy(alkyl)silanes are compatible during the process of insertion of sulfur dioxide. Additionally, diethoxydiarylsilanes are suitable under the conditions as well.