外消旋α-苯乙胺的合成及拆分

The Preparation and Splitting of Racemate α-Phenylethylamine

摘要: S-(-)-α-苯乙胺是制备磷霉素的中间体，并且是首选的酸性外消旋化合物拆分剂之一。本文利用苯乙酮与甲酸胺发生刘卡特反应合成外消旋α-苯乙胺，然后在甲醇中用L-酒石酸对α-苯乙胺进行化学拆分，最后对产品的红外光谱和紫外光谱进行了分析；通过条件实验得出了合成外消旋α-苯乙胺时最优的反应物比例为苯乙酮与甲酸胺的摩尔比为1:5，拆分α-苯乙胺时的最优温度为70℃、最优拆分时间为20 min，最优搅拌速度为240 r/min。在这些最优条件下做出的结果是；α-苯乙胺的最优产率为43.72%；拆分后的最优光学纯度为80.22%。

Abstract: S-(-)-α-phenylethylamine is an intermediate for the preparation of fosfomycin, which is one of the first choices for splitting the acidic racemic compounds as well. In this article, racemate-pheny- lethylamine was synthesized by the Leuckart reaction of acetophenone and ammonium formate. Then α-phenylethylamine was split by the L-tartaric acid in methanol. Finally, the infrared and ul-traviolet spectra of the products were analyzed. Through conditional experiments, the best ratio of reactants in the synthesis of racemic-phenylethylamine is 1:5 mole ratio of acetophenone to ammonium formate. The best temperature for splitting racemate-phenylethylamine is 70˚C. The best splitting time is 20 mins; the best stirring speed is 240 r/min. Under these optimal conditions, the best yield of α-phenylethylamine is 43.72%, and the best optical purity after splitting is 80.22%.