Exploiting benzene ring contraction to access high-value molecular scaffolds is challenging. Now, through photoexcitation of a transient intermediate generated during the interrupted Fischer indolization, the benzene ring contraction of arylhydrazines is unlocked to synthesize fused pyridines under mild conditions. The reaction shows good functional group tolerance and predictable regioselectivity.
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This is a summary of: Li, K. et al. Photoinduced benzene ring contraction of arylhydrazines for the synthesis of fused pyridines. Nat. Synth. https://doi.org/10.1038/s44160-025-00976-4 (2026).
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Synthesis of fused pyridines through photothermal cascade activation of arylhydrazines. Nat. Synth (2026). https://doi.org/10.1038/s44160-025-00974-6
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DOI: https://doi.org/10.1038/s44160-025-00974-6
