Chemistry of Oxaziridines. 13.1 Synthesis, Reactions, and Properties of 3-Substituted 1,2-Benzisothiazole 1,1-Dioxide Oxides

Abstract

The synthesis, properties, and reactions of 3-substituted 1,2-benzisothiazole 1,1-dioxide oxides 8, highly stable examples of 3,3-disubstituted N-sulfonyloxaziridines 3, are described. These new N-sulfonyloxaziridines are prepared in high yield by oxidation of the corresponding sulfonimines 7. The bicyclic sulfonimines were prepared by treatment of saccharin (5) or preferably pseudosaccharin ethyl ether 6 with organolithium reagents. Kinetic studies of the oxidation of sulfoxides to sulfones and the epoxidation of limonene reveal that these new oxidizing reagents exhibit reduced reactivity, but greater selectivity, compared to oxaziridines of type 1, in their oxygen-transfer reactions due to greater steric hindrance of the active-site oxygen. This is reflected in lower rates of oxidation and in improved cis/trans selectivity for the epoxidation of (+)-limonene. © 1990, American Chemical Society. All rights reserved.