

AN UNEXPECTED SYNTHESIS OF β-AMINO-α-MESYL-γ-SULTAMS UPON MESYLATION OF HINDERED α-AMINONITRILES

Abstract
We report one-pot procedure for an unexpected synthesis of previously unknown 4-amino-5-methylsulfonyl-2,3-dihydroisothiazole 1,1-dioxides (also called β-amino-α-mesyl-γ-sultams). Thus, the reaction of mesyl chloride with hindered α-aminonitriles is accompanied by the formation of interim N-(1-cyanoalkyl)(methylsulfonyl)methanesulfonamides which, in turn, undergo the сarbanion-mediated sulfonate (sulfonamido) intramolecular cyclization reaction yielding β-amino-α-mesyl-γ-sultams. The structure of the title compounds was confirmed by X-ray diffraction study. The proposed mechanistic insights of the reaction are in accordance with the results of additional experiments and literature data.
Keywords
aminonitriles; spiro compounds; sulfonamides; cyclization; X-ray study
Latvian Institute of Organic Synthesis - Aizkraukles iela, 21, Riga, LV-1006, Latvia - hgs@osi.lv