Better synthesis of moth pheromone

Abstract

The European grapevine moth (Lobesia botrana) spoils vineyard fruit across the globe. One of the most effective weapons against the pest is the moth’s own sex pheromone. When sprayed into the air around vineyards, it leads male moths on a fruitless chase to find females and disrupts mating. Although eco-friendly, the pheromone, (7E,9Z)-dodecadien-1-yl acetate, is about 60% more expensive than traditional pesticides. The standard synthetic route starts with a pricey eight-carbon alkyne and requires isolating four intermediates. Now, Gerard Cahiez of Chimie ParisTech, Olivier Guerret of M2i Life Sciences, and colleagues have come up with a less costly, one-pot synthesis and report making the pheromone on a 50-kg industrial scale (Org. Process Res. Dev. 2017, DOI: 10.1021/acs.oprd.7b00206). The new—and simpler—synthesis is based on a cross-coupling reaction between a dienol phosphate and a Grignard reagent that uses an iron-based catalyst instead of a more expensive palladium catalyst. The route starts with