Rational design of Lewis acid-base bifunctional nanopolymers with high performance on CO2/epoxide cycloaddition without a cocatalyst

Simultaneous Activation of Carbon Dioxide and Epoxides to Produce Cyclic Carbonates by Cross‐linked Epoxy Resin Organocatalysts

“…[23] Additionally, these catalysts can be easily recovered with a simple centrifugation operation, and the catalytic performance could be preserved over 7 repetitions. The remarkable catalytic reactivity of our epoxy resin catalysts is ascribed to the synergistic effect among the functional parts and the concurrence of both the epoxide activation route and the CO 2 activation route during the cycloaddition reaction, which is verified on the basis of 1 H NMR, 13 C NMR, 19 F NMR and in situ IR studies.…”

“…Collectively, the 1 H NMR spectra demonstrated the existence of the hydrogen-bonding interaction between FO and the hydroxyl group of catalyst 8. In the 19 F spectrum (Figure 5A), the addition of catalyst 8 to FO resulted in a new peak at À 77.07 ppm, which further proves the hydrogen-bonding interaction between FO and the hydroxyl group of catalyst 8, as the trifluoromethyl group could not directly form hydrogenbonding interaction with the hydroxyl group. [24] On the basis of these findings and the literature, a hydrogen-bonding-mediated catalytic mechanism for the cycloaddition reaction of CO 2 and epoxide catalyzed by cross-linked epoxy resin organocatalysts was proposed (Scheme 3, route 1).…”

“…These catalysts exhibited high catalytic activity and product selectivity (10 examples, > 99 %) during the reactions, especially for epichlorohydrin, which could be smoothly converted at ambient temperature and pressure. To clarify this delightful result, the activation processes of epoxides and CO 2 were investigated by 1 H NMR, 13 C NMR, 19 F NMR and in situ IR, and as a result, a novel mechanism for the simultaneous activation of CO 2 and epoxides was proposed. We hope that this work will provide a basis for the optimization of more bifunctional heterogeneous organocatalysts or the design of new catalysts.…”

“…[18] Liu and co-workers showed that Lewis acidicbasic bifunctional nanopolymers have important synergistic effects on the activation of CO 2 and epoxides, and ring-opening of epoxides. [19] Recently, we developed a series of bifunctional heterogeneous polymer catalysts by incorporating thiourea and quaternary ammonium salts. Owing to the synergistic effect of thiourea and quaternary ammonium salts, these catalysts demonstrated satisfactory catalytic performance to various epoxides.…”

A Novel POP-Ni Catalyst Derived from PBTP for Ambient Fixation of CO2 into Cyclic Carbonates

“…Although mild and efficient catalysts involving Zn or Co Lewis centers on the POP have been developed [ 36 , 37 , 38 ], the addition of TBAB as a cocatalyst was required, which may make the recovery of catalytic systems tedious and difficult. For other Mg 2+ -, Zn 2+ -, Co 2+ -, or Al 3+ -involved POP catalysts [ 39 , 40 , 41 , 42 , 43 , 44 , 45 ], higher temperatures or pressures were usually applied so that comparable yields could be obtained.…”