Redox‐Tuned Oxycarbamates Enable Divergent C─N and C─C Functionalization of Indolizines Under Photoredox Catalysis With Green Light
- 1Institute of Organic Chemistry Clausthal University of Technology Leibnizstr Germany
Abstract
Nitrogen‐centered radicals (NCRs) provide direct access to C─N bonds, but their broader use remains limited by the need for strongly reducing photocatalysts, high‐energy irradiation, and incomplete control over competing radical transfer pathways. Here we show that nonafluoromesitylsulfonyl (Nms)‐substituted oxycarbamates represent a redox‐lowered class of amidyl‐radical precursors that can be activated under green light by a bichromophoric ruthenium photocatalyst. The electron‐deficient sulfonyl group lowers the reduction potential of the N─O bond sufficiently to enable single‐electron cleavage under mild conditions. In DMF, the resulting amidyl radicals are trapped directly by indolizines to provide C3‐aminated heteroarenes. In DMSO, higher N‐alkyl homologues are switched via a 1,2‐hydrogen atom transfer (HAT) to α‐amino carbon‐centered radicals, enabling C─C bond formation from the same precursor family. This solvent‐gated divergence provides a unified entry to aminated and alkylated indolizines and establishes redox‐tuned oxycarbamates as versatile radical precursors for long‐wavelength photoredox synthesis.
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BibTeX
@article{stefanoni2026redoxtuned,
title = {{Redox‐Tuned Oxycarbamates Enable Divergent C─N and C─C Functionalization of Indolizines Under Photoredox Catalysis With Green Light}},
author = {Kevin Klaus Stefanoni and René Wilhelm},
journal = {Chemistry (Weinheim an Der Bergstrasse, Germany)},
year = {2026},
month = aug,
doi = {10.1002/chem.71550},
url = {https://doi.org/10.1002/chem.71550},
note = {CC BY 4.0},
}
RIS
TY - JOUR
TI - Redox‐Tuned Oxycarbamates Enable Divergent C─N and C─C Functionalization of Indolizines Under Photoredox Catalysis With Green Light
AU - Kevin Klaus Stefanoni
AU - René Wilhelm
PY - 2026
DA - 2026/08/07
JO - Chemistry (Weinheim an Der Bergstrasse, Germany)
DO - 10.1002/chem.71550
UR - https://doi.org/10.1002/chem.71550
AB - Nitrogen‐centered radicals (NCRs) provide direct access to C─N bonds, but their broader use remains limited by the need for strongly reducing photocatalysts, high‐energy irradiation, and incomplete control over competing radical transfer pathways. Here we show that nonafluoromesitylsulfonyl (Nms)‐substituted oxycarbamates represent a redox‐lowered class of amidyl‐radical precursors that can be activated under green light by a bichromophoric ruthenium photocatalyst. The electron‐deficient sulfonyl group lowers the reduction potential of the N─O bond sufficiently to enable single‐electron cleavage under mild conditions. In DMF, the resulting amidyl radicals are trapped directly by indolizines to provide C3‐aminated heteroarenes. In DMSO, higher N‐alkyl homologues are switched via a 1,2‐hydrogen atom transfer (HAT) to α‐amino carbon‐centered radicals, enabling C─C bond formation from the same precursor family. This solvent‐gated divergence provides a unified entry to aminated and alkylated indolizines and establishes redox‐tuned oxycarbamates as versatile radical precursors for long‐wavelength photoredox synthesis.
SN - 0947-6539
SN - 1521-3765
ER -