Abstract: The peach fruit moth is a significant pest of fruit crops. The primary component of its sex pheromone is (Z7)-eicosene-11-one (Z7-20-11kt). Using ethyl 4-bromobutyrate as the starting material, a Wittig reaction was conducted to synthesize ethyl (Z7)-undecenoate. This intermediate was subsequently hydrolyzed and acylated to yield (Z7)-undecenoyl chloride, which was then coupled with N,O-dimethylhydroxylamine to form the Weinreb amide 6. Finally, 6 was reacted with nonylmagnesium bromide to afford the target product Z7-20-11kt. The novelty of this synthetic route lies in the reductive addition of the Weinreb amide to a nonyl Grignard reagent to construct the ketone carbonyl group. This method utilizes relatively low-cost starting materials, achieves an overall yield of 35%, and has been successfully scaled up to kilogram-scale production. Field trials confirmed that the synthesized Z7-20-11kt exhibits a potent trapping effect against the target pest.
Zheng et al. (Fri,) studied this question.