Photoredox catalysis has developed into a powerful tool for the synthesis of organic compounds with diverse structures. However, stable carbon–chloride bonds remain beyond the energetic limits of the outer-sphere photoreductive activation. Here, we demonstrate that the organization of the reacting species in microstructured, aqueous solutions allows generation of carbon-centred radicals from non-activated alkyl chlorides in the presence of double bonds via assembly-promoted single electron transfer. Photocatalytic systems consisting of a surfactant, organic substrates and additives have been designed, characterized and applied for radical dechlorination, addition and cyclization reactions. Cheap and commercially available blue light-emitting diodes are used as the irradiation source for the transformations. Mechanistic studies indicate the accumulation of the energy of two visible light photons in one catalytic cycle.
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Data relating to the materials and methods, optimization studies, experimental procedures, mechanistic studies, DLS measurements and NMR spectra are available in the Supplementary Information. All other data are available from the authors upon reasonable request.
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We gratefully acknowledge funding from the German Research Foundation (DFG, GRK 1626, Chemical Photocatalysis and KO 1537/18-1) and the Ministry of Science and Higher Education of Poland (M.G., Mobility Plus, 1640/MOB/V/2017/0). We thank S. Crespi for his help with preparing the graphics.
The authors declare no competing interests.
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Giedyk, M., Narobe, R., Weiß, S. et al. Photocatalytic activation of alkyl chlorides by assembly-promoted single electron transfer in microheterogeneous solutions. Nat Catal 3, 40–47 (2020). https://doi.org/10.1038/s41929-019-0369-5
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