Synthesis of (+)-Disparlure from Diethyl (-)-Malate via Opening and Fragmentation of the Three-Membered Ring in Tertiary Cyclopropanols

(+)-Disparlure [(7R,8S)-7,8-epoxy-2-methyloctadecane, pheromone of the gypsy moth Lymantria dispar L.] was synthesized starting from diethyl (-)-malate via cyclopropanation of the ester groups, selective protection of the 1,3-diol functionality, and successive opening and fragmentation of the three-membered rings in the corresponding tertiary cyclopropanols as key stages.