Vicinal dual hydroxyl functional mesoporous poly(ionic liquid)s with large surface area and high ionic liquid (IL) content were synthesized through the copolymerization of epoxy-containing IL monomers and divinylbenzene, followed by ring opening in water. They acted as recyclable heterogeneous organocatalysts in the cycloaddition of a series of epoxides with CO 2 under mild conditions (down to ambient conditions). The catalyst can be lightly recovered and reused with stable activity. The remarkable performance was attributable to the abundant mesoporosity and the synergistic effect of vicinal dual hydroxyls as hydrogen-bonding donors and halogen anions as nucleophiles. Density functional theory calculation, comprising the structural optimization, the energetic profile, and the charge and energy decomposition analysis by the combination of the extended transition state energy decomposition scheme with the natural orbitals for chemical valence approach, was performed to afford insight, indicating that the vicinal dual hydroxyls accelerated the reaction by providing a strong hydrogen-bonding effect and enhancing the leaving ability of the halogen anions.

2-Phenylimidazoline based porous hypercrosslinked ionic polymers afforded high yields in the cycloaddition of epoxides with ambient or diluted CO2 (0.15 bar CO2 and 0.85 bar N2) under low or room temperature.

Meso-macroporous hierarchical poly(ionic liquid)s are ionothermally synthesized through self-polymerization of the new divinylimidazole IL, exhibiting enhanced CO2 capture and excellent activity in the cycloaddition of CO2 to epoxides.

An ionic copolymer catalyst with nanopores, large surface area, high ionic density, and superior basicity was prepared via the radical copolymerization of amino-functionalized ionic liquid bromide and divinylbenzene, followed with a hydroxyl exchange for removing bromonium. Evaluated in chemical fixation of CO2 with epoxides into cyclic carbonates in the absence of any solvent and basic additive, the nanoporous copolymer catalyst showed high and stable activity, superior to various control catalysts including the halogen-containing analogue. Further, high yields were obtained over a wide scope of substrates including aliphatic long carbon-chain alkyl epoxides and internal epoxide, even under atmospheric pressure and less than 100 °C for the majority of the substrates. On the basis of in situ Fourier transform infrared (FT-IR) investigation and density functional theory (DFT) calculation for the reaction intermediates, we proposed a possible reaction mechanism accounting for the superior catalytic activity of the ionic copolymer. The specifically prepared ionic copolymer material of this work features highly stable, noncorrosive, and sustainable catalysis and, thus, may be a new possibility for efficient chemical fixation of CO2 since it is an environmentally friendly, metal-free solid catalyst.

Mesoporous poly(ionic liquid)s were synthesized by radical copolymerization of the ionic liquid 1‐aminoethyl‐3‐vinylimidazolium bromide with divinylbenzene plus the ion exchange of bromide anions with hydroxyls. Characterizations revealed the high ionic liquid content, large surface area, and hydrophobicity for the sample prepared with equimolar amounts of ionic liquid and divinylbenzene, with good accessibility to organic compounds and resistance to CO2/H2O contamination. The mesoporous copolymer behaved as a superior and recyclable solid‐base catalyst for solvent‐free Knoevenagel condensation of benzaldehyde with ethyl cyanoacetate, giving the much higher turnover frequency of 304 h−1 (yield 99 %, 0.5 h) than those of the nonporous analogues, commercial strong basic resins, and even homogeneous NaOH. The high activity was confirmed by Knoevenagel condensation with various substrates and Claisen–Schmidt condensation. A possible synergistic Lewis–Brønsted dual‐base‐center mechanism is proposed for understanding the catalytic behavior.