Preparation of fluorinated alkenes in ionic liquids

The utility of ionic liquids (8-ethyl-1,8-diazabicyclo[5,4,0]-7-undecene trifluoromethanesulfonate and 8-methyl-1,8-diazabicyclo[5,4,0]-7-undecene trifluoromethanesulfonate) as a safe recyclable reaction medium for the synthesis of α-fluoro-α,β-unsaturated esters by the Horner–Wadsworth–Emmons reaction with aldehydes in the presence of base, is described.