Ionic Porous Organic Polymer Loaded with Zn(II) Ions for Efficient Cycloaddition of CO₂ and Epoxides to Cyclic Carbonate

In order to effectively convert greenhouse gas CO₂ into high value-added chemicals, simple and sustainable methods are urgently needed. In this study, a novel metal-anchored ionic porous organic polymer (M-iPOP) named Zn-HUT4 was synthesized via a very simple and low-cost synthesis process. Further investigation was conducted into the use of Zn-HUT4 as a heterogeneous catalyst in the cycloaddition reaction of CO₂ with epoxides. The obtained Zn-HUT4 catalyst had a rich porous structure and abundant metal anchor points, which can effectively promote mass transfer in the cycloaddition reaction and offer a substantial amount of Zn­(II) ions as catalytic active sites. Using CO₂/propylene oxide (PO) cycloaddition as a model reaction, the effect of a series of conditions on catalytic experiments was explored. The Zn-HUT4 catalyst had good recyclability and substrate universality.