First synthesis of gem-difluorothiiranes from cycloaliphatic thioketones and difluorocarbene

Abstract

The reaction of sterically crowded cycloaliphatic thioketones with phenyl(trifluoromethyl)mercury and sodium iodide in boiling benzene yielded gem-difluorothiiranes in fair yields whereas in the case of aromatic thioketones gem-difluoroalkenes were obtained. The formation of these products is rationalized by an addition of difluorocarbene onto the C,S-double bond, followed by the extrusion of sulfur.