The utilization of covalent organic frameworks (COFs) for visible-light-driven C-N bond coupling represents a promising and environmentally sustainable approach to synthesize amine derivatives. However, its practical application has been hindered by inefficient metal-photoactive center synergy and poor structural stability. Herein, we design a “three-in-one” strategy to address these challenges through positional tuning of nitrogen atoms in the COF building blocks, leading to enhanced electron transfer efficiency, reduced activation barrier of metal catalytic centers and improved catalyst stability. Combining in-situ characterization with computational calculations, we identify two critical factors governing electron transfer between metal and photosensitizer: the electron transfer distance and electron density of the metal centers. The reduced electron density at the metal center not only facilitates efficient electron acceptance but also lowers the activation barrier, enabling highly efficient C-N coupling with broad scope. Furthermore, nitrogen positional modulation optimizes the coordination environment of Ni atoms, forming a stable five-membered imine-coordinated ring that significantly enhances catalyst stability. The heterogeneous metallaphotocatalyst Ni@Bpma-COF, designed based on this strategy, demonstrates exceptional performance in Buchwald-Hartwig aminations of challenging aryl chlorides and weakly nucleophilic reagents (morpholine), achieving a turnover frequency (TOF) of 442 h⁻¹, an 88-fold improvement over previous systems. Life cycle assessment (LCA) across four sustainability metrics, reveals that our catalytic system reduces the environmental footprint by 48% compared to previous reports, showcasing unparalleled advantages in environmental sustainability.
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