Electrophotochemical Ce-Catalyzed Radical Truce–Smiles Rearrangement of Cycloalkanols
Muhammad Adnan Bashir, Yong Jiang, Cai Zhai, Chunhong Hu, Zhiyang Lin, Chen Zhu
Abstract
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.