Convenient synthesis of the sex pheromone and its isomers of Lasioderma serricorne

The sex pheromone of Lasioderma serricorne and its isomer, 7-hydroxyl-4,6-dimethylnonan-3-one(7), have been synthesized in an overall yield of 61% starting from 2,4-dimethylglutaric acid via esterification, reduction, Grignard reaction, mono-etherification, oxidation and deprotection reaction sequence. Another sex pheromone and its isomer 2,6-diethyl-3,5-dimethyl-3,4-dihydro-2H-pyran(8), were obtained by cyclodehydration of 7-hydroxy-4,6-dimethylnonan-3-one. The structures of products were confirmed by NMR and MS spectra spectroscopies.