The aphid sex pheromone

Many species of pest aphids reproduce sexually on the winter host. The sex pheromone of the vetch aphid, Megoura viciae, has recently been identified as comprising the,(4aS,7S,7aR)- isomers of nepetalactone and nepetalactol. The stereochemistry at carbon-1 of the lactol was not defined, but is now shown, by X-ray crystallography on the 3,5- dinitrobenzoate ester, to have the R configuration, This lactol is the major product from reduction of the lactone with diisobutylaluminium hydride. Results from the similar reduction of other nepetalactone isomers are presented.