Concise Synthesis of (+)-allo-Kainic Acid via MgI2-Mediated Tandem Aziridine Ring Opening–Formal [3 + 2] Cycloaddition

Abstract

3-Methyl vinyl aziridine undergoes a mild MgI2-promoted S(N)2' ring opening and concomitant cyclization with fumarate Michael acceptors to give trisubstituted pyrrolidines. The process is efficient and highly diastereoselective. This methodology has been applied to a concise asymmetric synthesis of (+)-allo-kainic acid.