Stereocontrolled Synthesis of Difunctionalized Azetidinones and β2, 3‐Amino Acid Derivatives from Cyclodienes by Ring‐Opening and Cross‐Metathesis Reactions

Abstract

AbstractA stereocontrolled approach to highly functionalized 3,4‐disubstituted azetidin‐2‐ones and β2, 3‐amino acid derivatives from readily available cycloalkadienes was achieved. The syntheses involved 1,3‐dipolar cycloaddition of chlorosulfonyl isocyanate, followed by ring‐opening metathesis of the unsaturated bi‐ or tricyclic β‐lactams, and cross‐metathesis of the resulting divinyl‐substituted azetidinones. The substituted lactams were subsequently transformed by heteroring‐opening into the corresponding functionalized acyclic β2, 3‐amino acid derivatives.