A Versatile Ni(II) MOF Catalyst for Synthesis of Oxazolidinones via Three-Component Fixation of CO ₂ and Synthesis of Imines via Aerobic Oxidation of Benzylamine

A new Ni(II)-based metal-organic framework (MOF), designated as <b>IITG-8</b> (IITG stands for Indian Institute of Technology, Guwahati), has been successfully synthesized and thoroughly characterized. The thermally activated form of <b>IITG-8</b> (<b>IITG-8a</b>) was employed as an efficient heterogeneous catalyst for the multicomponent synthesis of oxazolidinones via CO₂ fixation and aerobic oxidative coupling of benzylamines. For oxazolidinone synthesis, <b>IITG-8a</b> achieved 94% conversion under solvent-free conditions (80 °C, 12 h) using tetrabutylammonium bromide (TBAB) as a cocatalyst. On the other hand, the catalytic performance of <b>IITG-8a</b> was also examined in the aerobic oxidative coupling of benzylamine without involving any radical initiator or oxidant. The broad substrate scope and reusability over four consecutive cycles for both transformations underscore the potential catalytic applications of <b>IITG-8a</b>. Mechanistic insights into the catalytic cycle were thoroughly investigated through a comprehensive literature review and systematic control experiments, providing a detailed understanding of the reaction. Moreover, the performance of <b>IITG-8a</b> was also compared with the reported catalysts. Thus, this work presents a sustainable and atom-economical approach for the synthesis of valuable oxazolidinones and imines while simultaneously addressing CO₂ utilization, contributing to both green chemistry principles and pharmaceutical intermediate synthesis.