Decarboxylative aldol reaction of ,-difluoro--ketocarboxylate salt: a facile method for generation of difluoroenolate

We developed a decarboxylative aldol reaction using ,-difluoro--ketocarboxylate salt, carbonyl compounds, and ZnCl2/N,N,N,N-tetramethylethylenediamine. The generation of difluoroenolate proceeded smoothly under mild heating to provide ,-difluoro--hydroxy ketones in good to excellent yield (up to 99%). The ,-difluoro--ketocarboxylate salt was bench stable and easy to handle under air, which realizes a convenient and environmentally friendly methodology for synthesis of difluoromethylene compounds.