Imidazolium‐Based Ionic Polymers Containing Electrostatic and Triple Hydrogen Bond for Efficient Conversion of CO <sub>2</sub> into Cyclic Carbonates
Xiahong Xu, Yan Sui, Wen‐Tong Chen, Lanxin Chai, Xiaodan Li, Wei Huang, Gangyong Zhou, Yuntong Li, Hong Zhong
Abstract
Abstract The catalytic conversion of carbon dioxide (CO 2 ) into valuable chemicals offers a promising solution to mitigate global warming. However, the high thermodynamic and kinetic stability makes CO 2 activation challenging, typically requiring harsh conditions. This study presents an ionic polymer, (HO) 3 ‐ImbTbIP, synthesized via the quaternarization of 1,2,4,5‐tetrakis(bromomethyl)benzene (Tb) with 1,3,5‐tri(1 H ‐imidazol‐1‐yl)benzene (Imb) and 2‐(hydroxymethyl)‐2‐(1 H ‐imidazol‐1‐yl)propane‐1,3‐diol (HO) 3 . The polymer features imidazolium ionic liquids and triple hydrogen bonds, where (HO) 3 moieties weaken the C─O bond of epoxides, and bromide anions act as nucleophiles to facilitate epoxide ring‐opening. Simultaneously, CO 2 activated by imidazolium reacts with oxyanion intermediates to form alkyl carbonate species. Remarkably, (HO) 3 ‐ImbTbIP efficiently converts CO 2 to cyclic carbonates under mild conditions (120 °C, 1 bar CO 2 ). This work advances the understanding of CO 2 conversion and highlights the potential of task‐specific polymers for sustainable catalysis.