title: Catalytic Carbocation Generation Enabled by the Mesolytic Cleavage of Alkoxyamine Radical Cations.
abstract: A new catalytic method is described to access carbocation intermediates via the mesolytic cleavage of alkoxyamine radical cations. In this process, electron transfer between an excited state oxidant and a TEMPO-derived alkoxyamine substrate gives rise to a radical cation with a remarkably weak C-O bond. Spontaneous scission results in the formation of the stable nitroxyl radical TEMPO(.) as well as a reactive carbocation intermediate that can be intercepted by a wide range of nucleophiles. Notably, this process occurs under neutral conditions and at comparatively mild potentials, enabling catalytic cation generation in the presence of both acid sensitive and easily oxidized nucleophilic partners.
authors.affiliation: Department of Chemistry, Princeton University, Princeton, New Jersey, 08544, USA.
authors.forename: Qilei
authors.initials: Q
authors.lastname: Zhu
authors.affiliation: Department of Chemistry, Princeton University, Princeton, New Jersey, 08544, USA.
authors.forename: Emily C
authors.initials: EC
authors.lastname: Gentry
authors.affiliation: Department of Chemistry, Princeton University, Princeton, New Jersey, 08544, USA. rknowles@princeton.edu.
authors.forename: Robert R
authors.identifier: 0000-0003-1044-4900
authors.initials: RR
authors.lastname: Knowles
mesh_terms: D000438:Alcohols / Q000737:chemistry*; D000588:Amines / Q000737:chemistry*; D002384:Catalysis; D002412:Cations / Q000737:chemistry; D008968:Molecular Conformation; D009942:Organometallic Compounds / Q000737:chemistry*; D055668:Photochemical Processes
chemical_list: D000438:Alcohols; D000588:Amines; D002412:Cations; D009942:Organometallic Compounds; C059688:alkoxyl radical
keywords: alkoxyamines; carbocations; mesolytic cleavage; photoredox catalysis; radical cations