Pheromones Eysarcoris lewisi

A simple example of the examination of a proposed structure through synthesis is provided in this section. In 2005, Takita12 proposed the structure of the male-produced aggregation pheromone of the stink bug Eysarcoris lewisi as the sesquisabinene alcohol, ( )-2-methyl-6-(4 -methylenebicyclo[3.1.0]hexyl)hept-2-en-l-ol (8) (Scheme 1). Mori13 synthesized (61 )-8 and (6S)-8 from the enantiomers of citronellal (10). The key steps were the intramolecular addition of an ct-keto carbene to the alkene bond (11—>12) and ( )-selective olefination of 13 to give 14. The 1H- and 13C-NMR spectra of 8 around the trisubstituted double bond at C-2 were different from those of the natural pheromone. 

Scheme 2 Synthesis of the male-produced aggregation pheromone of the stink bug Eysarcoris lewisi. Reagents ...

Figure 4.11 Elucidation of the correct gross structure of the pheromone of Eysarcoris lewisi by synthesis...

Preparation of bicyclic alcohol (6/ ,1 S,4 S,5 / )-51, which was converted to the pheromone of Eysarcoris lewisi. 

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