Sulfinates from Amines: A Radical Approach to Alkyl Sulfonyl Derivatives via Donor–Acceptor Activation of Pyridinium Salts
Jonathan A. Andrews, Loïc Pantaine, Christopher F. Palmer, Darren L. Poole, Michael C. Willis
Abstract
Synthetically versatile alkyl sulfinates can be prepared from readily available amines, using Katritzky pyridinium salt intermediates. In a catalyst-free procedure, primary, secondary, and benzylic alkyl radicals are generated by photoinduced or thermally induced single-electron transfer (SET) from an electron donor–acceptor (EDA) complex, and trapped by SO2 to generate sulfonyl radicals. Hydrogen atom transfer (HAT) from Hantzsch ester gives alkyl sulfinate products, which are used to prepare a selection of medicinal chemistry relevant sulfonyl-containing motifs.
Topics & Concepts
SulfonylChemistryPyridiniumAlkylRadicalAcceptorElectron acceptorCatalysisSalt (chemistry)Combinatorial chemistryHydrogen atomPhotochemistryOrganic chemistryCondensed matter physicsPhysicsSulfur-Based Synthesis TechniquesRadical Photochemical ReactionsCatalytic C–H Functionalization Methods