title: Divergence between organometallic and single-electron-transfer mechanisms in copper(II)-mediated aerobic C-H oxidation.
abstract: Copper(II)-mediated C-H oxidation is the subject of extensive interest in synthetic chemistry, but the mechanisms of many of these reactions are poorly understood. Here, we observe different products from Cu(II)-mediated oxidation of N-(8-quinolinyl)benzamide, depending on the reaction conditions. Under basic conditions, the benzamide group undergoes directed C-H methoxylation or chlorination. Under acidic conditions, the quinoline group undergoes nondirected chlorination. Experimental and computational mechanistic studies implicate an organometallic C-H activation/functionalization mechanism under the former conditions and a single-electron-transfer mechanism under the latter conditions. This rare observation of divergent, condition-dependent mechanisms for oxidation of a single substrate provides a valuable foundation for understanding Cu(II)-mediated C-H oxidation reactions.
authors.affiliation: Department of Chemistry, University of Wisconsin-Madison, 1101 University Avenue, Madison, Wisconsin 53706, USA.
authors.forename: Alison M
authors.initials: AM
authors.lastname: Suess
authors.forename: Mehmed Z
authors.initials: MZ
authors.lastname: Ertem
authors.forename: Christopher J
authors.initials: CJ
authors.lastname: Cramer
authors.forename: Shannon S
authors.initials: SS
authors.lastname: Stahl
mesh_terms: D003300:Copper / Q000737:chemistry*; D004579:Electron Transport; D015394:Molecular Structure; D009942:Organometallic Compounds / Q000138:chemical synthesis / Q000737:chemistry*; D010084:Oxidation-Reduction
chemical_list: D009942:Organometallic Compounds; D003300:Copper