Pheromone synthesis. Part 166. Synthesis of (2E,5R,6E,8E)-5,7-dimethyldeca-2,6,8-trien-4-one, the major component of the sex pheromone of the Israeli pine bast scale, and its antipode

Abstract

Both the enantiomers (1 and 1′) of (2E,6E,8E)-5,7-dimethyldeca-2,6,8-trien-4-one, the major component of the female-produced sex pheromone of the Israeli pine bast scale (Matsucoccus josephi) have been synthesized by starting from (2S,3R)-4-acetoxy-2,3-epoxybutan-1-ol 5, which was obtained by enzymatic asymmetric hydrolysis of the corresponding meso-diacetate E. Bioassay of the pheromone enantiomers showed that the (R)-isomer 1 is the natural pheromone.