The first enantiomerically pure thiadiazol-3-one 1-oxide and thiatriaza-indene 3-oxide systems chiral at the sulfur atom

The first synthesis of an enantiomerically pure C2 symmetric benzothiadiazole 2-oxide is described along with the first synthesis of an enantiomerically thiadiazol-3-one 1-oxide and a thiatriaza-indene 3-oxide system both chiral at the sulfur atom. Excellent levels of diastereoselectivity were observed in the SO installation step, that is, the reaction of the prerequisite bis-amines with thionyl chloride at ambient temperature.