Copper-Catalyzed Synthesis of 2H-Thiopyran Derivatives from Alkynes, Sulfonyl Azides, Carbon Disulfide, and Malononitrile

A one-pot synthesis of functionalized thiopyran derivatives via a Cu-catalyzed multicomponent reaction of sulfonyl azides, arylacetylenes and dipotassium 2,2-dicyanoethylene-1,1-dithiolate, generated from malononitrile and CS2, has been developed. When alkylacetylenes were used as the terminal alkynes, N-(alkanethioyl)-N-(2,2-dicyanoethanethioyl)methanesulfonamides were obtained in good yields.