Synthesis of Imidazolium-Functionalized COFs and Their Catalytic Performance in Cycloaddition of CO₂ with Propylene Oxide to Propylene Carbonate

Abstract

Herein, we constructed a novel heterogeneous catalyst (ILs-TPN-COFs), was constructed through synthesis of a new covalent organic framework (COFs) followed by modification with imidazole-based ionic liquids. A series of characterizations, such as NMR, FT-IR, and XPS verified the successful preparation of the catalyst. The catalytic performance of ILs-TPN-COFs was evaluated in the cycloaddition reaction of CO₂ and propylene oxide (PO) to produce propylene carbonate (PC). Under optimized reaction conditions (160 °C, 2.0 MPa, 2.5 wt.% catalyst amount, 8 h) the PC yield was up to 99.23%. Furthermore, the response surface experiment (RSM) was conducted on the reaction, the predicted results exhibited excellent agreement with the experimental results, indicating that the model is accurate. This work offers valuable insights into the synergistic effects of multi-component catalysts for the design and development of CO2 cycloaddition reactions.