Functionalized COFs with Quaternary Phosphonium Salt for Versatilely Catalyzing Chemical Transformations of CO_(2)

摘要

Currently,it encounters great challenges to accomplish catalyzing various kinds of carbon dioxide(CO_(2))conversion reactions efficiently with single catalyst,let alone control the interplay among catalytic efficiency and selectivity evenly.Here,we prepared a functional covalent organic framework,[PTPP]X%-TD-COF[PTPP=3-bromopropyltriphenylphosphonium;TD=1,3,5-tri(4-aminophenyl)benzene-1,4-diformylbenzene],by immobilizing the quaternary phosphonium salt onto the skeleton of COFs through a post-synthesis strategy for versatilely catalyzing reduction of CO_(2) and CO_(2) fixation on epoxide and aziridine facilely.With the typical features of COFs(such as porosity and ordered structure)and catalytic activity of the quaternary phosphonium salt,[PTPP]X%-TD-COF possesses an intensely synergistic effect for catalyzing the chemical transformations of CO_(2).Noteworthily,the quaternary phosphonium salt functionalized COFs catalyze the CO_(2) reduction reaction with amine and phenylsilane to produce formylated and methylated products under gentle reaction conditions with high selectivity and efficiency.Furthermore,[PTPP]_(X%)-TD-COF shows high catalytic ability in CO_(2) chemical fixation reactions.