A general preparative method for bishomoallyllithiums consists of reductive lithiation by 4, 4′-di-tert-butylbiphenylide (LDBB) of bishomoallyl phenyl sulfides, which can be prepared by (1) thioacetalization of γ, δ-unsaturated ketones followed by replacing one of the phenylthio groups with an alkyl group or a hydrogen or (2) Wittig or Peterson olefination of γ (phenylthio) ketones prepared in turn by conjugate addition of phenylthiomethyl cuprates ...