Chelation and Stabilization\nof Dynamic Single- Atom\nCu in Metal–Organic Frameworks for Selective Hydrogenation\nReactions

Selective hydrogenation of unsaturated carbonyl compounds\ninto\nalcohols is of great importance in the fine chemical industry. Herein,\nwe reported a robust and reusable single-atom Cu catalyst, Cu₁@MOF-303, fabricated by a covalent attachment of Cu atoms\nto the adjacent pair of unsaturated N atoms from two neighboring organic\nligands in a metal–organic framework for the selective hydrogenation\nof aldehydes/ketones, exhibiting high activity with complete conversion\nand 95% selectivity accompanied by a high product formation rate of\n23.6 h^–1. A combination of experimental and theoretical\nstudies revealed that the distinctive electronic and structural attributes\nrendered Cu₁@MOF-303 capable of adsorbing targeted functional\ngroups in reactants and desorbing desired products preferentially\ndue to the atomically dispersed Cu species chelated and stabilized\nby N atoms as well as the dynamic changes by breaking the interfacial\nCu–N bonds on reactant adsorption and making these bonds on\nproduct desorption, thereby enhancing the catalytic activity and stability.