Ethyl 2, 4-difluoroacetoacetate, ethyl ethoxalylfluoroacetate and the analogous benzyl ester gave the normal Wittig reaction with triethyl phosphonoacetate, whilst ethyl formylfluoroacetate gave a dimer of diethyl 4-fluoroprop-1-ene-1, 3-dicarboxylate. Treatment of the sodio-enolate of ethyl formylfluoroacetate with acid chlorides gives 3-acyloxy-2- fluoroacrylates. The acyloxy-group of these compounds can be replaced easily by ...
