Preparative Scale Syntheses of Isomerically Pure (10E,12E,14Z)- and (10E,12E,14E)-Hexadeca-10,12,14-trienals, Sex Pheromone Components of Manduca sexta
作者:Xin Chen、Jocelyn G. Millar
DOI:10.1055/s-2000-6227
日期:——
Short, efficient syntheses yielding products of very high isomeric purity have been developed for (10E,12E,14E)-hexadeca-10,12,14-trienal 1 and the (10E,12E,14Z)-isomer 2, the key pheromone components of the tobacco hornworm moth Manduca sexta. The penultimate (EEZ)-trienol, and aldehyde 1, were freed from isomeric impurities by selective reaction of the impurities with tetracyanoethylene. (EEE)-Aldehyde 2 was prepared by Wittig reaction of (2E,4E)-hexa-2,4-dienyltriphenylphosphonium bromide with 10-acetoxydecanal, deprotection, selective crystallization of the (EEE)-trienol from the resulting mix of isomers, and oxidation. The yield of the (EEE)-trienol was increased further by iodine-catalyzed isomerization of the mix of isomers in the liquor, and further recrystallization.
已开发出简短、有效的合成方法,能够获得具有很高异构体纯度的产品,包括烟草角虫蛾(Manduca sexta)的关键信息素成分(10E,12E,14E)-十六烯-10,12,14-醛1和(10E,12E,14Z)-异构体2。倒数第二步的(EEZ)-三烯醇和醛1通过与四氰乙烯的选择性反应去除了异构体杂质。通过将(2E,4E)-六烯-2,4-二烯基三苯基磷盐溴化物与10-乙酰氧基十醛进行Wittig反应,去保护,选择性结晶从结果异构体混合物中得到(EEE)-三烯醇,并进行氧化,制得(EEE)-醛2。通过对混合异构体的碘催化异构化和进一步再结晶,进一步提高了(EEE)-三烯醇的产率。