Guangzhou Chemical Industry

摘要

Benzoin condensation reaction catalyzed by VB1 is generally carried out in sodium hydroxide solution. In spite of relatively high yield, this method suffers from occasional failure caused by ring-opening of thiazole system of VB1 , namely low reproducibility. Benzoin was prepared by benzoin condensation reaction catalyzed by VB1 and phase transfer catalyst in the presence of sodium carbonate, and the preparing process was optimized by single factor experiment and orthogonal design method. Experimental results showed that, when 10. 5 g (0. 1 mol) of benzaldehyde was condensed catalyzed by 1. 75 g of VB1and 2. 0 g of tetrabutylammonium bromide at 70 ℃ for 2 h in solution of 12 mL 95% ethanoland 8 mL of water, the yield of benzoin was reached 67. 24%. The synthesis method is simple, safety, high yield and good reproducibility.%以V B1为催化剂的安息香缩合反应一般在氢氧化钠溶液中进行,虽然产率较高,但V B1的噻唑环易开环失效,反应的重现性较低。以碳酸钠为碱性试剂,通过单因素实验和正交试验优化了V B1催化下的安息香缩合反应工艺条件。实验结果表明,10.5 g (0.1 mol)苯甲醛在1.75 g (0.005 mol) VB1和10.0 mL 10% Nα2 CO3催化下,在乙醇水溶液(12 mL 95%乙醇加8 mL蒸馏水)中,70℃反应2.0 h,收率可达到67.2%。该法具有操作简单,安全,产率高和重现性好等优点。