A process is described in which a lactone ##STR1## is reacted with an alkylester X.sup.1 --CH.sub.2 and an oxidizing or dehydrogenating agent to form the phenol ester ##STR2##
A new strategy for the synthesis of 3,5-disubstituted phenols is established through one-pot Robinson annulation of α,β-unsaturated ketones with α-fluoro-β-ketoesters followed by in situ dehydrofluorination and tautomerization. This method has been extended to the synthesis of polysubstituted phenols and applied in the preparation of biologically active compounds.