Highly Diastereoselective Preparation of Aldol Products Using New Functionalized Allylic Aluminum Reagents

Chloro-substituted triethylsilyl enol ethers derived from cyclo­hexanone and related ketones are converted with aluminum powder in the presence of indium trichloride to functionalized allylic aluminum reagents which represent a new type of synthetic equivalent of metal enolates. These allylic organometallics undergo highly diastereo­selective additions to aldehydes and methyl aryl ketones, giving aldol products with a β-quaternary center.