Preparation of Alpha-Fluoro-Alpha, Beta-Unsaturated Esters via Two Carbon Homologation of Esters.

摘要

Alpha-Fluoro-Alpha, Beta-unsaturated esters of defined stereochemistry are useful building blocks for the synthesis of biologically active 12-fluororetinal and 12-fluororhodopsin, fluorinated mimics of insect sex pheromones of the silkworm moth Bombyx mori, and in the field of pyrethroids. In the presence of diisobutyl aluminum hydride, esters react with an anion derived from (EtO)2P(O)CFHC(O)OEt to give the title compounds in good yields. The scope of this method and the factors which influence the stereochemistry of the products are discussed. Keywords: Ethylene oxide, Phosphates, Fluorine aldehydes, Fluorinated hydrocarbons, Reprints. (aw)