Stereoselective Synthesis of Homofarnesenes: Establishment of an Efficient Method for the Stereoselective Preparation of Acyclic Tetrasubstituted Olefins

[Image: see text] A new method for the stereoselective synthesis of tetrasubstituted olefins is described. β-Ketophosphonates are alkylated via conventional methods, and a Grignard reagent is used to diastereoselectively add to the carbonyl group of the resulting intermediates. The elimination of hydroxyl phosphonates yielded the desired tetrasubstituted olefins in a stereoselective manner. Thus, homofarnesenes of fire ant trail pheromones have been synthesized efficiently using this strategy.