Regioselective α-Alkylation of Silyl Enolates using a Mild Catalyst- ZnCl₂ Doped on Acidic Alumina

Abstract

ZnCl₂ doped acidic alumina used as a solid support acts as a better Lewis acid in the SNl reaction of trimethyl silyl enol ethers with 3⁰, allylic and benzylic halides to yield exclusively the substituted product in excellent yields. This method has been employed for the synthesis of monocyclic sesquitepene hydrocarbon, (±)-β-bisabolene and a monoterpene, 2,6-dimethyl-7-octen-4-one.