Visible-Light-Accelerated Copper-Catalyzed [3 + 2] Cycloaddition of <i>N</i>-Tosylcyclopropylamines with Alkynes/Alkenes
M. Kumar, Shalini Verma, Vivek Mishra, Oliver Reiser, Akhilesh K. Verma
Abstract
Copper-catalyzed [3 + 2] cycloadditions of N-tosylcyclopropylamine with alkynes and alkenes have been accomplished under visible light irradiation. The developed approach is compatible with a range of functionalities and allows the synthesis of diversified aminated cyclopentene and cyclopentane derivatives being relevant for drug synthesis. The protocol is operationally simple and economically affordable as it does not require any ligand, base, or additives. As the key step, the one-electron oxidation of the N-tosyl moiety by visible light-induced homolysis of a transient Cu(II)-tosylamide complex is proposed, providing a facile entry for N-centered radicals.
Topics & Concepts
ChemistryHomolysisCycloadditionRadicalCatalysisCyclopenteneMoietyCombinatorial chemistryVisible spectrumPhotochemistryLigand (biochemistry)CopperOrganic chemistryBiochemistryReceptorOptoelectronicsPhysicsCyclopropane Reaction MechanismsCatalytic C–H Functionalization MethodsRadical Photochemical Reactions