Fluorine in pheromones: Synthesis of fluorinated 12-dodecanolides as emerald ash borer pheromone mimetics

Abstract A series of five 12-dodecanolides have been synthesised containing CF 2 groups at C5, C6, C7, C8 and in one case a double substitution at C5 & C8, as a strategy to bias the conformational space accessed by these macrocycles, and to assess if the analogues may act as mimetics for 12-decenolide pheromones associated with the Emerald Ash Borer. Accordingly individual syntheses of 5,5-difluoro- 5 , 6,6-difluoro- 6 , 7,7-difluoro- 7 , 8,8-difluoro- 8 and 5,5,8,8-tetrafluoro- 9 , 12-decanolides is outlined and X-ray structural data was obtained for three ( 5 , 8 and 9 ) of these compounds. The structures show clearly that the CF 2 groups occupy ‘corner’ locations in the macrocycle consistent with their ability to bias accessible conformations. The fluorine containing 12-dodecanolides all generated an electro-antennogram response in female beetles.