Ligand-regulated synthesis of two cerium-based MOFs for catalytic conversion of CO₂ into high-value-added chemicals

The effective capture and conversion of CO₂ into high-value chemicals are highly valuable and challenging. Herein, two cerium-based metal-organic frameworks (MOFs), compound 1 {Ce(HL₁)(H₂O)₃}_n and compound 2 {Ce(HL₂)(H₂O)₂}_n with 2D and 3D structures, respectively, were synthesized through ligand regulation and structurally characterized. Catalytic investigation demonstrated that the cycloaddition reaction between CO₂ and aziridine can be catalyzed by compounds 1 and 2 at 60 °C and 1 MPa over 8 hours, affording oxazolidone yields of 95% and 99%, respectively. Obviously, they showed distinct differences in substrate adaptability. The combination of substrate activation experiments and ¹H NMR spectroscopic characterizations confirms the synergistic effect between the Ce³⁺ active sites and co-catalyst TBAB, and a possible catalytic reaction mechanism is proposed. This work enriches the variety of catalytic rare-earth-based MOF materials.