Urapidil is an important drug for the treatment of essential hypertension and intravenously in hypertensive emergencies. Herein, an improved route to Urapidil was introduced. The new designed synthetic route starts with the addition reaction of 1-(2-methoxyphenyl)piperazine and oxetane catalyzed by Yb(OTf)₃ in acetonitrile to form the key intermediate 3-(4-(2-methoxyphenyl)piperazin-1-yl)propan-1-ol. Additionally, 3-(4-(2-methoxyphenyl)piperazin-1-yl)propan-1-ol was purified by recrystallization from the optimized solvents, which was beneficial to large scale production. Intermediate 3-(4-(2-methoxyphenyl)piperazin-1-yl)propyl-4-methylbenzenesulfonate was cast directly for the subsequent reaction without further purification. The overall yield of this route is about 45%. The structure of the final product was well confirmed by ¹H-NMR, ¹³C-NMR and HRMS.

乌拉地尔是治疗原发性高血压和高血压急症静脉注射的重要药物。在此，介绍了通往乌拉地尔的改进路线。_{新设计的合成路线首先在乙腈中Yb(OTf) 3}催化下1-(2-甲氧基苯基)哌嗪与氧杂环丁烷发生加成反应，生成关键中间体3-(4-(2-甲氧基苯基)哌嗪-1-基) )丙-1-醇。此外，通过从优化的溶剂中重结晶纯化3-(4-(2-甲氧基苯基)哌嗪-1-基)丙-1-醇，有利于大规模生产。中间体3-(4-(2-甲氧基苯基)哌嗪-1-基)丙基-4-甲基苯磺酸盐无需进一步纯化，直接用于后续反应。该路线总体收率约为45%。最终产物的结构通过¹ H-NMR、¹³ C-NMR 和 HRMS 得到了很好的证实。