Titanium(II)-based Z-reduction of alkynes. Syntheses of deuterium labelled linolenic and oleic acids and (3E,8Z,11Z )-tetradeca-3,8,11-trienyl acetate, the sex pheromone of a tomato pest, Scrobipalpuloides absoluta
作者:Natasha L. Hungerford、William Kitching
DOI:10.1039/a800674a
日期:——
An operationally simple TiII-mediated, stereo- and regio-specific reduction of isolated, conjugated and methylene ‘skipped’ polyynes to the corresponding Z-polyenes in a one-pot procedure is described and applied inter alia to the syntheses of deuterium labelled linolenic and oleic acids. Final quenching with D2O (instead of H2O) results in regio- and stereo-specific Z-dideuteration of the alkyne. The synthesis of (3E,8Z,11Z)-tetradeca-3,8,11-trienyl acetate, the major sex pheromone of Scrobipalpuloides absoluta, a destructive pest of tomatoes, and the (3Z,8Z,11Z)-isomer, utilises this methodology in key reduction steps, and under- or over-reduction are negligible.
本文描述了一种操作简便的TiII介导的一锅法立体和区域选择性还原孤立共轭亚甲基跳跃多炔烃至相应的Z-多烯烃的方法,并应用于氘标记亚麻酸和油酸的合成。最终用D2O(而非H2O)淬灭反应,实现了炔烃的区域和立体选择性双氘化。(3E,8Z,11Z)-十四碳-3,8,11-三烯基乙酸酯(主要性信息素)和(3Z,8Z,11Z)异构体的合成,利用了这种方法在关键还原步骤中,且不足或过度还原的情况可忽略不计。