THE WITTIG REACTION OF PERFLUORO-ACID DERIVATIVES - ACCESS TO FLUORINATED ENOL ETHERS, ENAMINES, AND KETONES

The preparation of novel perfluoroalkyl-substituted compounds in good yields is described. This preparation involves the Wittig reaction of a phosphonium ylide with perfluoroalkyl acid derivatives. The influence of the structure of the starting alkylidenetriphenylphosphoranes, the perfluoroalkyl reagents, and the reaction conditions has been investigated. Trifluoroacetamides lead to a Z/E mixture of enamines 3. Perfluoroalkyl esters (Rf = CF3, C2F5, C3F7, C7F15, CF2Cl) lead to only the (Z)-enol ethers 8-12 when reactions are performed with NaNH2 as a base and to 1-perfluoroalkyl ketones 13-17 when reactions are performed with BuLi.