Quaternary ammonium and copper phthalocyanine functionalized polyurea heterogeneous catalysts for CO2 and epoxides cycloaddition

Converting CO 2 efficiently into high-value-added chemical products represents dual value in ecological conservation and resource valorization. Designing novel catalysts integrating atom economy and process intensification constitutes the cornerstone for catalytic CO 2 conversion. Herein, an integrated polymeric heterogeneous catalyst is constructed by covalently anchoring functional groups of quaternary ammonium (QA) and copper phthalocyanine (CuPc) onto a polyurea (PU) framework, yielding PU-CuPc-QA. This catalyst is subsequently applied for CO 2 conversion to cyclic carbonates. Owing to the Cu 2+ centers in phthalocyanine and urea groups from PU acting as a Lewis acid and hydrogen bond donor (HBD) to efficiently activate epoxide, as well as nucleophilic attack of this activated epoxide by iodide ion (I - ) dissociated from QA, PU-CuPc-QA facilitates ring-opening of epoxide. Moreover, the phthalocyanine rins and the QA cations in PU-CuPc-QA work as N -rich groups that can adsorb and active CO 2 . As a result, PU-CuPc-QA exhibits exceptional catalytic activity for CO 2 cycloaddition under mild conditions without adding any external co-catalysts. Specially, at 100 o C, 1.5 MPa of CO 2 , 6%(mass) PU-CuPc-QA achieve 99% propylene carbonate yield and selectivity after reacting with propylene oxide for 6 h. Combining its ability to catalyze and activate epoxide and CO 2 simultaneously, PU-CuPc-QA is a promising catalyst for CO 2 cycloaddition.