Novel stereoselective alkylation of 4-t-butylcyclohexanone using trimethylaluminium in benzene

Abstract

Although alkylation of 4-t-butylcyclohexanone in tetrahydrofuran and diethyl ether using Me₂Zn, Me₂Cd, Me₂Mg, MeMgX (where X = F, Cl, Br), and Me₃Al produces predominantly the cis-alcohol (ca. 75% in tetrahydrofuran), alkylation using Me₃Al in benzene at a Me₃Al: ketone ratio of 2:1 or greater produces predominantly (ca. 90%) the trans-alcohol.