Cycloaddition of the Trimethylenemethane-Palladium Complex to Activated Six-Membered and Medium-Ring Enones

Abstract

2-Carbomethoxycyclohexenones and -0ctenones react with (Z-(acetoxymethyl)-3-allyl)trimethylsilane in the presence of Pd(O) to give methylenecyclopentane cycloadducts in yields ranging from 46–92%. The corresponding 2-methyl derivatives proved far less reactive (only 5% trapping).