合成联苯-4-甲酸的新方法

Novel Synthesis of Biphenyl-4-carboxylic Acid

以联苯和草酰氯为原料,通过傅克酰基化反应合成联苯-4-酮酸乙酯,经碱性水解得联苯-4-酮酸,在双氧水作用下,酮酸发生氧化脱羰基反应得目标产物。对酰化条件进行了优化并详细考察了氧化剂种类、双氧水浓度、物料配比、反应温度和时间对氧化脱羰基反应的影响,确定较佳的工艺条件:10%双氧水作氧化剂,n(联苯-4-酮酸)∶n(双氧水)=1∶2,反应时间为3 h,反应温度为0~5℃。在此条件下,联苯-4-甲酸的收率为81.9%(以原料联苯计),纯度为99.5%(HPLC面积归一化法)。产物结构经熔点、~1HNMR和^(13)CNMR和质谱表征。

Biphenyl4-carboxylic acid was synthesized from biphenyl and oxalylchloride by Friedel-Crafls acyl reaction, alkaline hydrolysis and oxidative decarboxylation. The effects of reactions on the yield of biphenyl-4-earboxylie acid have been investigated and the optimized conditions are as follows ：10% H2O2 as the oxidative reagent,the molar ratio of biphenyl-4-keto acid and H202 is 1 ： 2 ,the reaction temperature is 0 - 5 ℃ and the reaction time is 3 h. Under the optimized conditions,the yield of biphenyl--4- carboxylic acid can reach 81.9% and the purity is higher than 99.5% （HPLC area normalization method）. The obtained biphen- yl-4-carboxylic acid has been identified by m. p. ,IHNMR , 13CNMR and MS.