Stereoselective Synthesis of α-fluoro-β-trifluoromethyl-α,β-unsaturated Esters by Horner-Wadsworth-Emmons Coupling

α-Fluoro-β-trifluoromethyl-α,β-unsaturated esters were synthesized via the reaction of diethyl (1-fluoro-1- carbethoxymethyl) phosphonate with a variety of aromatic/heterocyclic trifluoromethyl ketones and trifluoroacetaldehyde ethyl hemiacetal by the Horner-Wadsworth-Emmons (HWE) coupling. The effect of base, solvent, as well as reactant ratio has been investigated. The present method is highly stereoselective, attractive and convenient for the synthesis of the target compounds due to the availability of the reagents, simplicity of the approach and good yields of the products.