Metal–Organic Framework: An Emergent Catalyst in C–N Cross-Coupling Reactions

Scientific and industrial concern on the rational design of metal–organic frameworks (MOFs) has marked an escalating trend in recent years and rejuvenated. The emergence of C–N cross-coupling reactions gains huge attention for the production of nitrogen-functionalized molecules in value-added pharmaceuticals, tailor-made therapeutics, smart optoelectronic devices, energy harvesting functional materials, etc. Recently, MOF-mediated C–N cross-coupling reactions hold a great promise to replace homogenous and heterogeneous catalysts owing to promising structural features like intriguing porous framework, large catalytic sites and surface area, adequate framework stability, flexible organic linkers, minimal leaching, and easy recyclability. At first, the importance of MOFs and MOFs catalyzed C–N cross-coupling reactions and their beneficial roles over homogeneous and a limited number of other heterogeneous catalysts are fundamentally introduced. Then, the state-of-the-art synthetic approaches for pristine and decorated MOFs are comprehensively reviewed and discussed. The emergence of MOFs as heterogeneous catalysts has been critically analyzed and illuminated with an overview of the mechanistic aspects in various C–N cross-coupling reactions namely Ullmann coupling, Chan-Lam coupling, Buchwald-Hartwig amination, C–H activation and aziridination reactions. Thereafter, different structural parameters conferring the stability and recyclability of the MOFs in the cross-coupling reactions are enumerated. Finally, we forecast the future perspectives on MOFs catalyzed C–N cross-coupling reactions and associated challenges to establish the practical applicability of the catalyst at the industrial level.