Sex pheromone of pine sawflies: Enantioselective lipase catalysed transesterification of erythro-3,7-dimethylpentadecan-2-ol, diprionol

Article abstract of DOI:10.1016/0957-4166(96)00428-4

(2S,3S,7R/S)-3,7-Dimethylpentadecan-2-ol (2S,3S,7R/S)-1 was prepared with less than 0.5% of (2R,3R,7R/S)-3,7-dimethylpentadecan-2-ol via Pseudomonas sp. (PSL) catalysed transesterification of a 1:1:1:1 mixture of the four erythro-3,7-dimethylpentadecan-2-ols and vinyl acetate in n-heptane at initial low water activity (a(w) < 0.1). (2S,3S,7S)-3,7-Dimethylpentadecan-2-ol (Diprionol) is the precursor to the behaviourally active diprionyl acetate used by the female pine sawfly Neodiprion sertifer as a sexual pheromone. Several lipases, solvents and reaction conditions were tested, and the best results (enantiomeric ratio E = 110) were obtained with Pseudomonas sp. (PSL) and vinyl acetate in iso-octane at initial water activity a(w) < 0.32. When using Candida rugosa (CRL, immobilised on polypropylene) as the catalyst in an esterification reaction with rac-4-methyl-dodecanoic acid and eicosanol at a(w) = 0.8 in cyclohexane a pronounced enantioselectivity was obtained (E = 19). Copyright (C) Elsevier Science Ltd.