摘要
在自制的四种季盐相转移催化剂和氯化锂的催化作用下 ,由苯甲醛 ,氯仿和氨合成了医药中间体 (± ) - α-氨基苯乙酸 ,研究了催化剂的催化性能 ,选择了较佳的催化剂和合成反应的较佳条件。结果表明 ,在苯甲醛和催化剂的摩比为 1∶ 1 ;氯化锂与苯甲醛的摩尔比为 2∶ 1 ;反应温度控制在 0～ - 1 5°C之间 ;反应时间 4h的条件下 ,(± ) - α-氨基苯乙酸其化学产率达 72 %。该合成法具有收率较高且避免了 Strecker合成法使用高毒性原料的特点 ,反应条件较易达到。其存在的不足是催化剂不易分离 ,不能反复利用。提出了解决该问题的途径之一是采用“三相转移催化剂”。
Four phosphoninum salt type phase transfer catalysts were prepared. The reaction of chloroform, benzaldehyde and aqueous ammonia was carried out in the presence of phosphonium salt phase transfer catalysts and lithium chloride under two phase conditions to prepare (±) α amino phenylacetic acid, a medical intermediate. The better reaction conditions and the better phosphonium salt phase transfer catalysts were found. When the mol ratio of benzaldehyde and phase transfer catalyst is 1∶1, the mol ratio of lithium chloride and benzaldehyde is 2∶1, the reaction temperature is 0～ -15 °C and the time of reaction is 4 h, the yield of (±) α amino phenylacetic acid is 72%. The yield of this method is higher, and it avoids the use of poisonous raw materials in the Strecker method. The short coming of the method is that the catalyst cannot be separated and reused. It is proposed that to adopt a “triphase transfer catalyst” may solve these problems.
出处
《化学世界》
CAS
CSCD
北大核心
2003年第2期86-87,93,共3页
Chemical World
