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Updated: Jan 11, 2026
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Cercosporin-Photocatalyzed [4+1]- and [4+2]-Annulations of Azoalkenes Under Mild Conditions
Published on: July 17, 2020
Electrophotochemical Ce-Catalyzed Radical Truce-Smiles Rearrangement of Cycloalkanols
Muhammad Adnan Bashir1, Yong Jiang1, Cai Zhai1
1Ningbo Institute of Digital Twins Eastern Institute of Technology, Ningbo 315200, China.
None:
The Truce-Smiles rearrangement enables access to arylethylamines in pharmaceuticals, yet typically requires amide substrates or prefunctionalized radical precursors. We report a redox-neutral electrophotochemical rearrangement of cycloalkanols catalyzed by inexpensive cerium salts. Alkoxy radicals are generated directly from unmodified alcohols via ligand-to-metal charge transfer, triggering β-scission and 1,4-aryl migration to furnish β-arylethylamines. The method avoids external oxidants, precious metals, and preinstalled radical handles, operating under mild conditions with broad scope, high functional-group tolerance, and scalability. Mechanistic experiments and computations reveal a Ce(III)/Ce(IV) catalytic cycle and radical ipso substitution through a spirocyclic dearomatized intermediate. This platform expands access to arylethylamines from cycloalkanols.
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