The direct reduction of inert planar arenes and heteroarenes with visible light remains rarely explored, as the energy of one visible-light photon is unable to overcome the stabilization of aromatics. Here we report a system based on boron carbonitride semiconductor, which can reduce arenes and heteroarenes in water under blue light irradiation. The system features the advantage of low-cost, high-efficiency, facile separation, benign environmental profile and broad substituent tolerance. The methodology can be extended to late-stage functionalization and/or deuteration of drugs, hormones and axially chiral compounds with conserved chirality. Moreover, gram-scale synthesis is successfully implemented with catalyst recycling. Mechanistic investigations support a consecutive blue-light-induced energy and electron transfer process, which accumulates sufficient energy to reduce arenes to arene anions by absorbing two photons successively. The metal-free system introduces a simple and sustainable reactivity mode for semiconductor photocatalysts and enriches the chemical toolkit for a class of demanding and valuable organic transformations.
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The data generated in this study are provided in the article and the Supplementary Information file or are available from the corresponding author upon reasonable request. Atomic coordinates of the optimized computational models are provided in Supplementary Data 1. Source data are provided with this paper.
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This work was financially supported by the National Key Technologies R & D Program of China (2018YFA0209301, X.W.), the National Natural Science Foundation of China (22071026, M.Z.; U1905214, X.W.; 22032002, X.W.; 21961142019, X.W. and 21973014, W.L.), the Chang Jiang Scholars Program of China (T2016147, X.W.) and the 111 Project (D16008, X.W.).
The authors declare no competing interests.
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Supplementary Methods, Notes 1–3, Figs. 1–33, Tables 1–8 and references.
Atomic coordinates of the optimized computational models.
Source Data Fig. 2
SEM, TEM and EELS mapping images, XRD pattern and high-resolution XPS spectra.
Source Data Fig. 3
Activity, AQE, UV-Vis DRS and FTIR spectra.
Source Data Fig. 4
Mott-Schottky plots, UV-Vis absorption, steady-state fluorescence, phosphorescence (PH), time-resolved PH decay, photocurrent and EPR spectra. Activity with different irradiation density of light.
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Yuan, T., Sun, L., Wu, Z. et al. Mild and metal-free Birch-type hydrogenation of (hetero)arenes with boron carbonitride in water. Nat Catal 5, 1157–1168 (2022). https://doi.org/10.1038/s41929-022-00886-0