Insect sexual pheromones prepn. - involving reaction of halo-nonenyne with Grignard reagent

摘要

Stereoselective synthesis of sexual pheromones includes the step of reacting a suitable isomer of a 1-halo-non-4-en-6-yne (II) with a Grignard reagent of formula (III) in the presence of Li2CuCl4:- (where X and X' are halogen). Cpd. (I) can be converted to 1-acetoxy-7E, 9Z-dodecadiene, which is the female sex attractant of Lobesica botrana. Prods. with a stereochemical purity of 95% can be obtd.