Ionic Liquid/Zn-PPh3 Integrated Porous Organic Polymers Featuring Multifunctional Sites: Highly Active Heterogeneous Catalyst for Cooperative Conversion of CO2 to Cyclic Carbonates

A series of ionic liquid (IL), zinc halide (ZnX 2 ), and triphenylphosphine (PPh 3 ) integrated porous organic polymers (POPs) featuring multifunctional sites were afforded through solvothermal synthesis for cyclic carbonate synthesis which utilizes epoxides and carbon dioxide (CO 2 ). Owing to the cooperative effect of ionic liquid and homogeneously distributed Zn-PPh 3 specie, which is probably strengthened by the confined microporous structure and flexible frameworks, these POPs catalysts exhibited high CO 2 capture and conversion performance and provided the highest activity (initial turnover frequencies up to 5200 h –1 ) of heterogeneous catalysts reported to date within the context of cyclic carbonate formation. Even more surprising, very favorable turnover numbers (TONs) of 2120 and 720 were attained at 40 and 25 °C, respectively. The effect of reaction parameters (reaction time, temperature, CO 2 pressure) on the catalytic performance as well as other epoxide substrates were also investigated in detail. Furthermore, the catalyst can be easily recovered and reused five times without a significant loss of activity. These ionic liquid and Zn-PPh 3 constructed porous polymers may provide an industrial opportunity for cyclic carbonate products.