Synthesis of γ,γ-difluoro-β-hydroxy-δ-lactones as new precursors of HMG-CoA reductase inhibitor

A series of γ,γ-difluoro-β-hydroxy-δ-lactones 1 were efficiently synthesized as new precursors of HMG-CoA reductase inhibitor in one pot by treatment of readily prepared gem-difluoromethylenated acetonides 3 with trifluoroacetic acid. Contrarily, acetonides 3 could be transformed to the γ,γ-gem-difluoromethylenated α,β-unsaturated δ-lactones 2 through hydrolyzation and lactonization in refluxing toluene.