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Author Spotlight: Accelerating Discovery in Microporous Material Chemistry
Published on: October 6, 2023
Tuning Selectivity in Reductive Amination Through Orbital Symmetry Engineering of Metal-Organic Supports
Huiwen Gao1,2, Caoyu Yang1,2, Jinghao Wang1,2
1Laboratory of Nanosystem and Hierarchical Fabrication, National Center for Nanoscience and Technology, Beijing, P. R. China.
Abstract:
Controlling selectivity in the reductive amination of carbonyls, a pivotal green route to amines, remains a long-standing challenge within complex reaction networks. Here, we report a strategy to precisely steer product selectivity by engineering the orbital symmetry of coordinatively unsaturated metal sites (CUSs) on metal-organic layers (MOLs) that support ruthenium nanoparticles (Ru NPs). Across diverse substrates, Zn-based MOLs with Zn2(CO2)4 paddle-wheel secondary building units (SBUs) favor primary amines, whereas their Cu-based analogues with Cu2(CO2)4 SBUs solely produce Schiff bases. This divergence originates from a picoscale symmetry-broken Cu-O4 geometry in the Cu2(CO2)4 unit, which weakens the adsorption and activation of Schiff base intermediates, thereby kinetically retarding their further ammonolysis. Our work establishes a paradigm for controlling catalytic selectivity through picoscale orbital symmetry manipulation at support metal sites.
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