title: Copper-catalyzed direct C-H oxidative trifluoromethylation of heteroarenes.
abstract: This article describes the copper-catalyzed oxidative trifluoromethylation of heteroarenes and highly electron-deficient arenes with CF(3)SiMe(3) through direct C-H activation. In the presence of catalyst Cu(OAc)(2), ligand 1,10-phenanthroline and cobases tert-BuONa/NaOAc, oxidative trifluoromethylation of 1,3,4-oxadiazoles with CF(3)SiMe(3) proceeded smoothly using either air or di-tert-butyl peroxide as an oxidant to give the corresponding trifluoromethylated 1,3,4-oxadiazoles in high yields. Di-tert-butyl peroxide was chosen as the suitable oxidant for oxidative trifluoromethylation of 1,3-azoles and perfluoroarenes. Cu(OH)(2) and Ag(2)CO(3) were the best catalyst and oxidant for direct oxidative trifluoromethyaltion of indoles. The optimum reaction conditions enable oxidative trifluoromethylation of a range of heteroarenes that bear numerous functional groups. The prepared trifluoromethylated heteroarenes are of importance in the areas of pharmaceuticals and agrochemicals. The preliminary mechanistic studies of these oxidative trifluoromethylations are also reported.
authors.affiliation: Key Laboratory of Organofluorine Chemistry, Shanghai Institute of Organic Chemistry, Chinese Academy of Science, 345 Lingling Lu, Shanghai 200032, China.
authors.forename: Lingling
authors.initials: L
authors.lastname: Chu
authors.forename: Feng-Ling
authors.initials: FL
authors.lastname: Qing
mesh_terms: D002384:Catalysis; D003300:Copper / Q000737:chemistry*; D006571:Heterocyclic Compounds; D015394:Molecular Structure; D010069:Oxadiazoles / Q000737:chemistry; D010084:Oxidation-Reduction; D013237:Stereoisomerism
chemical_list: D006571:Heterocyclic Compounds; D010069:Oxadiazoles; D003300:Copper