文章研究了普通铜粉催化体系催化氰化物与NaN3的[2+3]环加成反应。研究结果表明,以铜粉作为催化剂,Et3N作为助催化剂,DMF/MeOH(9∶1)为溶剂,将氰化物与NaN3于常压、温度为55-60℃下反应12 h,合成5-取代四唑化合物,其收率可达85%左右。该方法具有催化剂廉价易得且用量少、反应条件温和、耗时少、产率高、后处理操作简单等优点。
The [2+3] cycloaddition of cyanides and NaN3 catalyzed by copper powder was studied. The reaction was efficiently performed in the presence of copper powder as the catalyst and Et3N as the promoter in DMF/MeOH (9 : 1) at constant pressure and temperature 55-60 ℃ for 12 h, affording 5-disubstituted-tetrazoles in excellent yields which was about 85 %. The procedure was characterized by lower amount of inexpensive catalyst, mild reaction condition, little time-consuming, high productivity and easy operation.