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A COF-based catalyst was synthesized to activate C–H bonds for C–C/C–N coupling via hydrogen atom transfer. The catalyst can be easily recycled, allowing downstream modification of the product to realize C–H to C–N/C–S/C–O transformations. 

Abstract Phosphine‐ligated transition metal complexes play a pivotal role in modern catalysis, but our understanding of the impact of ligand counts on the catalysis performance of the metal center is limited. Here we report the synthesis of a low‐coordinate mono(phosphine)‐Rh catalyst on a metal‐organic layer (MOL), P‐MOL • Rh, and its applications in the hydrogenation of mono‐, di‐, and tri‐substituted alkenes as well as aryl nitriles with turnover numbers (TONs) of up to 390000. Mechanistic investigations and density functional theory calculations revealed the lowering of reaction energy barriers by the low steric hindrance of site‐isolated mono(phosphine)‐Rh sites on the MOL to provide superior catalytic activity over homogeneous Rh catalysts. The MOL also prevents catalyst deactivation to enable recycle and reuse of P‐MOL • Rh in catalytic hydrogenation reactions. 

Abstract Although many monometallic active sites have been installed in metal–organic frameworks (MOFs) for catalytic reactions, there are no effective strategies to generate bimetallic catalysts in MOFs. Here we report the synthesis of a robust, efficient, and reusable MOF catalyst, MOF‐NiH, by adaptively generating and stabilizing dinickel active sites using the bipyridine groups in MOF‐253 with the formula of Al(OH)(2,2′‐bipyridine‐5,5′‐dicarboxylate) forZ‐selective semihydrogenation of alkynes and selective hydrogenation of C=C bonds in α,β‐unsaturated aldehydes and ketones. Spectroscopic studies established the dinickel complex (bpy⋅⁻)Ni^II(μ₂‐H)₂Ni^II(bpy⋅⁻) as the active catalyst. MOF‐NiH efficiently catalyzed selective hydrogenation reactions with turnover numbers of up to 192 and could be used in five cycles of hydrogenation reactions without catalyst leaching or significant decrease of catalytic activities. The present work uncovers a synthetic strategy toward solution‐inaccessible Earth‐abundant bimetallic MOF catalysts for sustainable catalysis.