Thioalkylation of Enolates, III. Stereoselective Synthesis of Steroids and Related Compounds, II α-Thioalkylation of Zinc Dienolates to 4-Substituted 1-tert-Butoxy-7a-methyl-hexahydroinden-5-ones
α-Alkylation of the α,β-unsaturated ketone 1 at C-4 has been achieved by thioalkylation of the corresponding zinc dienolate with α-chlorosulfides of type 2. The desulfurization of the β-(phenylthio) ketones 4 leads directly to the 4-substituted hexahydroinden-5-ones 5.