Fenton's Reagent in Dimethyl Sulphoxide: an Unusual Sulphonylating System. X-Ray Crystallographic Analysis of 4-N,N-Dimethylamino-N,N-dimethanesulphonylaniline

On treatment with Fenton's reagent in dimethyl Sulphoxide nitrosoarenes form sulphonylate products, while the expected N,O-dimethylated hydroxylamine is isolated only in the case of nitrosobenzene in low yield. Nitrosobenzene and 4-cyanonitrosobenzene lead to N-sulphonylhydroxylamines while 4-nitroso-N,N-dimethylaniline and 1-nitroso-2-phenyl-3-acetylindolizine give sulphonamides and ring-sulphonylated products. A nitrenium cation is suggested to play a primary role in this process. X-Ray analysis of the title compound confirms the trigonal planar arrangement of the dimethylamino group and its coplanarity with the benzene ring, as expected in accord with the results found in related derivatives.