New synthetic method to 1,2-benzisothiazoline-3-one-1,1- dioxides and 1,2-benzisothiazoline-3-one-1-oxides from N-alkyl(o- methyl)arenesulfonamides

Article abstract of DOI:10.1016/S0040-4020(99)00974-6

Various N-alkylsaccharins were easily prepared in moderate to good yields by the reaction of N-alkyl(o- methyl)arenesulfonamides with (diacetoxyiodo)benzene in the presence of iodine under irradiation with a tungsten lamp (W-hv). On the other hand, irradiation of N- alky](omethyl)arenesulfonamide derivatives bearing various substituents on the aromatic ring with a high-pressure mercury lamp (Hg-hv), in the presence of (diacetoxyiodo)benzene and iodine gave the corresponding N-alkyl-1,2-benzisothiazoline-3- one-1-oxide derivatives in moderate yields, together with N- alkyl-1,2-benzisothiazoline-3-one-1,1-dioxide (saccharin) derivatives.