Synthesis and lipase catalysed stereoselective acylation of some 3-methylalkan-2-ols, identified as sex pheromone precursors in females of pine sawfly species

摘要

Several 3-methylalkan-2-ols precursors to sex pheromones of Diprion pini, Gilpinia pallida, Gilpinia frutetorum,nDiprion nipponica, Macrodiprion nemoralis and Microdiprion pallipes were synthesised as stereoisomeric mixtures innmoderate to good yields. The key reaction sequence in the syntheses was the ring opening of either cis- or racemicntrans-epoxybutane using a higher order cyanocuprate as nucleophile followed by a highly efficient lipase catalysednstereoselective acylation of the obtained 3-methylalkan-2-ol. The biologically active species specific stereoisomer wasnsynthesised as a single stereoisomer in high stereoisomeric purity, as one in a mixture of two or as one of fournstereoisomers when the appropriate 3-methylalkan-2-ol was stereoselectively acylated using a Pseudomonas sp. lipasenas catalyst.