Recyclable and Magnetically Functionalized Metal–Organic Framework Catalyst: IL/Fe₃O₄@HKUST-1 for the Cycloaddition Reaction of CO₂ with Epoxides

Abstract

A recyclable and magnetic nanocomposite catalyst (IL/Fe3O4@HKUST-1) was synthesized via grafting ionic liquid (IL) [AEMIm]­BF4 into magnetically functionalized metal–organic framework Fe3O4@HKUST-1 in a water–ethanol media. The properties of IL/Fe3O4@HKUST-1 were fully characterized by powder X-ray diffraction, electron microscopy, Fourier-transform infrared spectroscopy, nitrogen adsorption–desorption, density-functional theory, and a magnetic property measurement system. IL/Fe3O4@HKUST-1 showed high activity in the solvent-free cycloaddition of CO2 with epoxides under mild conditions. Furthermore, the catalyst can be easily separated from the reaction mixture, and the recycled catalyst maintained high performance for several cycles. The synergistic effect of the Lewis acid and base sites in IL/Fe3O4@HKUST-1 contributes to its greater reactivity than individual IL or HKUST-1.

Fluorine-Functionalized NbO-Type {Cu2}-Organic Framework: Enhanced Catalytic Performance on the Cycloaddition Reaction of CO2 with Epoxides and Deacetalization-Knoevenagel Condensation

“…However, entries 5 and 6 showed that epoxides with bulky substituent groups diffused inadequately in the nanovoids of NUC-54a and were inefficiently activated by the catalytic sites. The molecular size for selected epoxides is listed in Table S3, whereas it is worth mentioning that NUC-54a has better catalytic activity toward epoxides with bulky substituents than some reported MOF-based materials because of its larger void volume. − …”

Surface Modification of Magnetic ZIF-90 Nanoparticles Improves the Microenvironment of Immobilized Lipase and Its Application in Esterification

“…The absorption band at 1574 cm –1 was assigned to the stretching vibration of CC located in the IL framework. The results showed that MZIF-90 was successfully prepared and that ILs were grafted on MZIF-90 via a N–Zn coordination bond . The calculation results based on DFT showed that the adsorption bonding energy of cation [AMI] + on MZIF-90 was −5.01 eV, lower than anion [Tf 2 N] − on MZIF-90 (−4.02 eV).…”

“…The results showed that MZIF-90 was successfully prepared and that ILs were grafted on MZIF-90 via a N−Zn coordination bond. 47 The calculation results based on DFT showed that the adsorption bonding energy of cation [AMI] + on MZIF-90 was −5.01 eV, lower than anion [Tf 2 N] − on MZIF-90 (−4.02 eV). The calculated result indicated that the interaction between the cation of ILs and MZIF-90 was much stronger, which was consistent with the charge density difference map shown in Figure S1.…”

Amino-Functionalized Ionic-Liquid-Grafted Covalent Organic Frameworks for High-Efficiency CO2Capture and Conversion

“…With the massive consumption of fossil fuels, excessive carbon dioxide (CO 2 ) emissions are considered as a thorny climate and environmental problem. , However, as a reproducible and nontoxic C1 resource, CO 2 can be converted into high-value-added chemicals under certain conditions, realizing the efficient utilization of resources and reducing environment hazards. , The production of cyclic carbonates from CO 2 and epoxide by cycloaddition, as an atom-economic reaction, has attracted a surge of attention. , In view of the large-scale application of cyclic carbonates, homogeneous catalysts and heterogeneous catalysts such as ionic liquids (ILs), metal oxides, metal–organic frameworks (MOFs), zeolites, etc., have been extensively utilized for CO 2 cycloaddition. − A homogeneous system is not conducive to product separation . For most heterogeneous catalysts, the toxic metals can be released from metal oxides.…”