微波促进四苯基溴化磷催化合成氟代芳香醛(酮)

MICROWAVE-ASSISTED FLUORINATION IN PRESENCE OF TETRAPHENYLPHOSPHONIUM BROMIDE

在氟化钾作用下,以四苯基溴化磷为催化剂,微波促进卤素交换制备了氟代芳香化合物。考察了不同溶剂,不同助催化剂对反应的影响并与常规加热的反应进行了对比。结果表明,在硝基苯溶剂中,n(氯代芳香化合物):n(氟化钾)=1∶3、n(Ph_4PBr)∶n(氯代芳香化合物)=1∶10、n(冠醚)∶n(氯代芳香化合物)=1∶20,反应温度210℃条件下,合成了9种氟代芳香化合物,收率76%～92%,微波辅助反应比常规加热反应时间缩短2～3 h。

The fluorobenzaldehydes were prepared through the catalysis of Ph4PBr and KF under the irradiation of microwave. Nine fluorobenzaldehydes were prepared with the yields of 76 %-92% under the following conditions： n（chlorobenzaldehyde） ： n（KF）= 1 ：3, n（Ph4PBr） ： n（chlorobenzaldehyde）=1：10, n（crown ester） ： n（chlorobenzaldehyde）=1： 20 and reaction temperature 210 ℃. In comparison with oil heating, the reaction time could be shortened by more than 2 - 3 h, and the yields were increased by 3 %- 5 % by the microwave irradiation.