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用经典维悌希反应合成α,β-不饱和醛已有不少报导,反应条件比较苛刻。近年来相转移催化技术应用于维悌希反应的研究十分活跃,但迄今的研究主要是反应本身,关于带官能团的维悌希试剂的相转移反应报导很少。我们用带缩醛保护基的维悌希试剂在相转移条件上合成α,β-不饱和醛,立体选择性几乎百分之百,总收率较高。带其他官能团的维悌希试剂的相转移反应正在研究之中。另外,我们以乙酸乙烯酯为原料,与溴加成后直接与二醇缩合,一步合成了2-溴甲基-1,3二氧杂茂,产率70%,比文献报导的路线短、收率高。它与三苯膦成盐时加入适量溶剂,很方便地得到季鏻盐。
There are many reports on the synthesis of α, β-unsaturated aldehydes by the classical Vicki reaction, and the reaction conditions are quite harsh. In recent years, phase transfer catalysis has been used in the Wiegis reaction, but the main research to date is the reaction itself. There are few reports about the phase transfer reaction of the Wittig reagent with functional groups. We synthesized the α, β-unsaturated aldehydes on phase transfer conditions using a Wittig reagent with an acetal protecting group, with nearly 100% stereoselectivity and high overall yield. Phase transfer reactions with Wiegand reagents with other functional groups are under investigation. In addition, we use vinyl acetate as raw material, with bromine directly after the condensation with the diol, one-step synthesis of 2-bromomethyl-1,3-dioxane, the yield of 70%, shorter than the literature reported route, High yield. When it is added into salt with triphenylphosphine, it is convenient to get quaternary phosphonium salt by adding appropriate amount of solvent.