Sv. Pansare et al., STEREOSELECTIVE SYNTHESIS OF 3,4-DISUBSTITUTED 1,2,5-THIADIAZOLIDINE 1,1-DIOXIDES AND THEIR CONVERSION TO UNSYMMETRICAL VICINAL DIAMINES, Synlett, (6), 1998, pp. 623
Reaction of 3,4-disubstituted 1,2,5-thiadiazole 1,1-dioxides with Grig
nard reagents followed by stereoselective hydride reduction generates
unsymmetrical 1,2,5-thiadiazolidine 1,1-dioxides. These can be readily
converted to unsymmetrical vicinal diamines.