Boron-Doped Nanomaterials/Copper Synergistic Photocatalytic C(sp3)–N Cross-Coupling

Abstract Heterogeneous photocatalysis has emerged as a sustainable paradigm for C–N bond construction; however, its application has been predominantly confined to C(sp2)–N couplings, typically relying on the modulation of nickel catalytic cycles. The efficient construction of C(sp3)–N bonds remains a formidable challenge due to the high energy barriers of alkyl-metal oxidative addition and the inability of traditional semiconductors to orchestrate radical kinetics. Herein, we report a robust and versatile C(sp3)–N cross-coupling system enabled by a boron-doped nanomaterial (BDN) in synergy with a copper catalyst. The strategic incorporation of boron atoms─characterized by their vacant p-orbitals and Lewis acidity─into the heptazine framework transcends the role of simple light-harvesting, creating chemically active sites that effectively direct charge carrier separation and dictate alkyl radical generation. Extensive characterization, including quasi-in situ XPS and EPR, confirms that boron centers act as efficient electron acceptors, facilitating spatially directed charge transfer. This synergistic BDN/Cu platform accommodates an exceptionally broad substrate scope, including various N-nucleophiles (amides, sulfonamides, heterocycles) and diverse radical precursors (alkanes, alkyl boronic acids, and alkyl iodides). Furthermore, the protocol’s synthetic utility is underscored by its successful extension to C(sp2)–N arylation and its seamless transition to a continuous-flow system, achieving gram-scale production. This work provides a general strategy for molecular-level engineering of heterogeneous catalysts to unlock challenging bond-forming transformations.