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

Abstract

3-Methyl vinyl aziridine undergoes a mild MgI₂-promoted S_N2′ 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 (+)-<i>allo</i>-kainic acid