CO2 capture and conversion to di-functional cyclic carbonates in metalloporphyrin-based porous polyaminals with large surface area

Porphyrin- and cobalt (II)-metallated porphyrin-based porous polyaminals (PAN-TDP and [email protected]) were synthesized via one-step polycondensation reaction utilizing octo-functional 5,10,15,20-tetrakis (4-(2,4-di-aminotriazinyl)phenyl)-porphyrin (TDP) and cobalt (II)-metallated porphyrin ([email protected]) to polymerize with terephthalaldehyde, respectively. The achieved BET surface areas (1535–1589 m2 g−1) are the largest among the aminal-linked porous polymers already published in the literature. The synergistic role of nitrogen-rich polymer skeleton, ultramicroporous and microporous structure, and large specific surface area in [email protected] gives rise to high adsorption capacity of CO2 (17.9 wt%, 273 K/1 bar). Meanwhile, [email protected] exhibits excellent heterogeneous catalysis performance for the cycloaddition reactions of CO2 with various epoxides. Of particular interest is that the silicon- and sulfite-containing cycloaliphatic di-epoxides can be converted to cyclic di-carbonates with high conversion rates (88.7–90.5%) and TON values (825–842) despite the large steric hindrance. The generated novel silicon- and sulfite-containing cycloaliphatic di-functional carbonates are potential monomers for the preparation of isocyanate-free polyurethanes.