Photoredox Generation of Isothiouronyl Radical Cations: A New Platform in Covalent Radical Catalysis
Gaétan Archer, Pierre Cavalère, Maurice Médebielle, Jérémy Merad
Abstract
Thiyl radicals offer unique catalytic patterns for the direct covalent activation of alkenes. However, important limitations in terms of structural diversity and handling have hampered the routine use of thiyl radicals in covalent radical catalysis. Herein, we report a new class of cationic sulfur-centered radicals to achieve covalent radical catalysis. Their generation from highly modular thioureas by photoredox catalysis make their utilization very simple and reliable. The synthetic potential and the versatility of the catalytic system were finally evaluated in a (3+2)-radical cascade between vinylcyclopropanes and olefins.
Topics & Concepts
Photoredox catalysisRadicalChemistryCatalysisCovalent bondCationic polymerizationCombinatorial chemistryPhotochemistryOrganic chemistryPhotocatalysisCatalytic C–H Functionalization MethodsCyclopropane Reaction MechanismsRadical Photochemical Reactions