Abstract: Electrophilic addition of chlorosulfonyl isocyanate (CSI) to “aromatic” ketones 1 (R'COCH2RZ, R1 and/or R2= aryl) was found to be a synthetically versatile reaction, producing 2H-1, 3-oxazine-2, 4 (3H)-diones (6) when dichloromethane was the solvent and 1, 2, 3-oxathiazin-4 (3H)-one 2, 2-dioxides (4) as well (if R'= aryl) in diethyl ether solvent. A number of additional products are observed in low yield. An examination of substituent ...
