相转移催化法合成扁桃酸

Synthesis of Mandelic Acid in the by Use of Phase Transfer Catalyst

研究了相转移催化法合成扁桃酸的工艺,探讨了反应条件,特别是相转移催化剂的种类对产物收率的影响,发现除季铵盐外,叔胺对反应也具有良好的催化作用,提出了叔胺与二氯卡宾结合的催化机理。实验还发现,由辛可宁或麻黄碱衍生的手性相转移催化剂在有外加溶剂时才能诱导扁桃酸的不对称合成。

In this paper the synthesis of mandelic acid in the presence of a phase transfer catalyst was studied, the effect of reaction condition, in particular the kinds of phase transfer catalysts, on the yield of product was discussed. Tertiary amine is found to have favorable catalysis for reaction except quaternary ammonium salts, and the catalytic mechanism of tertiary amine combining with dichlorocarbene is also brought forward. During the experiments, it is discovered that chiral phase transfer catalysis deriving from cinchonine or ephedrine hydrochloride can induce the asymmetry synthesis of mandelic acid in the existence of adscititious solvent.