用4-二甲氨基吡啶催化合成苯甲酰苯巴比妥

THE CATALYTIC SYNTHESIS OF BENZOPHENOBARBITAL

以苯巴比妥、苯甲酰氯为原料 ,采用高效催化剂 4二甲氨基吡啶催化合成苯甲酰苯巴比妥 ,探讨了催化剂用量对产物收率的影响。实验表明在苯巴比妥∶苯甲酰氯∶三乙胺 (物质的量比 ) =1∶ 1 .0 2∶ 1 .0 2 ,苯为溶剂 ,反应温度为 5 5℃ ,时间为 1 .5 h,催化剂 4二甲氨基吡啶的用量 (质量分数 )为 3%条件下进行酰化反应 ,经分离、提纯 ,产物的收率可提高到 64% ;产物中 w (苯巴比妥 )≤ 0 .8% ,w ( N,N 二取代苯甲酰苯巴比妥 )≤ 0 .4 %

Benzophenobarbital was synthesized by acylation of phenobarbital with benzoyl chloride and triethyl amine in benzene. It was showed that 4dimethylaminopyridine(DMAP) is an effective catalyst for this synthesis. The optimum reaction conditions were that the molar ratio of phenobarbital∶benzoyl chloride∶triethylamine is 1∶1.02∶1.02 catalyzed by mass 3% of DMAP in benzene under reaction temperature 55 ℃ and reaction time 1.5 h. The yield of benzophenobarbital was about 64%, w(phenobarbital)≤0.8%, w( N,N dibenzophenobital)≤0.4%.