On the preparation and structure of some trans-fused ureas: perhydro-trans-thieno[3,4-d]imidazol-2-one SS-dioxides

Abstract

Reaction of trans-3,4-dibromotetrahydrothiophen dioxide with methylamine affords trans-tetrahydro-3 4-bis-(methylamino)thiophen dioxide. Reaction with phosgene then gave perhydro-1,3-dimethyl-trans-thieno-[3,4-d]imidazol-2-one SS-dioxide (3; R = Me), which was studied by X-ray crystallography. [Crystal data: a= 8.616(3), b= 15.280(5), c= 7.409(3)Åβ= 102.62(4)°, space group C2/c,Z= 4]. Ammonia gave a similar product. Piperidine also reacted with the dibromide to give the corresponding diamine, whereas pyridine afforded a novel pyridinium salt.