A Convenient Synthesis of Some Highly Hindered 4,4-Diaryl-2-Butenolides

Abstract

Bridged di(o-alkylaryl) tricyclic-γ-lactones have not been described in the literature and their preparation may be difficult by published methods. As a part of our studies on Grignard reactions with cyclic anhydrides^1-3 we describe herein a new and important aspect of the reaction of hindered magnesium compounds with exo 7-oxabicyclo[2.2.1]hept-4-ene-2,3-dicarboxylic anhydride.