Synthesis and Biological Activity of α‐Methylene‐γ‐butyrolactones

Abstract α‐Methylene‐γ‐butyrolactones [dihydro‐3‐methylene‐2(3 H )furanones] constitute an important group of natural products and possess wide‐ranging biological activities. Progress in the synthesis of the heterocycle and the classification of the synthetic methods are not only of practical interest, but also fundamentally important as a current example for the construction of an unusual 1,4‐functionality distance and an α‐substituted acrylic ester moiety which is susceptible to nucleophilic attack.