Selective five- and six-membered cyclic amine syntheses via capture of episulfonium ions

Org Biomol Chem. 2005 Apr 21;3(8):1369-71. doi: 10.1039/b503068b. Epub 2005 Mar 14.

Abstract

Amide nitrogens open episulfonium ions to form pyrrolidines or piperidines selectively, depending on the nitrogen substituent, in either reversible or irreversible reactions.