CO 2 Capture and Utilization: Selective Synthesis of 2‐Oxazolidinone by Employing Frustrated Lewis Pair‐Enriched Zn‐NC Catalyst Derived From MOF
Shanmugam Sujith, Murudappa Harsha, Hubli Krishnaprasad Meghana, Kalathiparambil Rajendra Pai Sunajadevi, Ganapati Venkatesh ShanbhagABSTRACT
In this study, CO 2 was captured in monoethanolamine, forming hydroxyethyl carbamate, which was subsequently converted into 2‐oxazolidinone under ambient conditions with the aid of a Zn‐NC catalyst derived from MOF. The catalyst was extensively characterized using PXRD, N 2 Sorption, NH 3 and CO 2 ‐TPD, H 2 ‐TPR, XPS, EPR, Raman, HRTEM, and FESEM. The catalytic performance was attributed to the presence of frustrated Lewis pairs (FLP) on the surface. The study of masking of active sites with pyridine and KSCN confirmed the FLPs as key active sites. Density Functional Theory studies revealed that the adsorption energy of the hydroxyl group and carboxylate group in the hydroxyethyl carbamic acid indicated the preferential adsorption modes. The charge density difference (CDD) analysis provided valuable evidence of how adsorption geometry influences electron redistribution, offering a supportive insight into likely reaction pathway and product selectivity. Under optimum reaction conditions determined by central composite design (CCD) model, highest yield of 84% was obtained for 2‐oxazolidinone using Zn‐NC catalyst. This study emphasizes the defective nature of Zn‐NC catalyst, resulting in the formation of FLPs contributing to an enhanced catalytic activity. The catalyst was resilient to leaching and was found to be recyclable up to 4 cycles.