title: Copper-catalyzed aerobic oxidative C-H functionalization of substituted pyridines: synthesis of imidazopyridine derivatives.
abstract: A novel, efficient, and practical method for the synthesis of imidazopyridine derivatives has been developed through the copper-catalyzed aerobic oxidative C-H functionalization of substituted pyridines with N-(alkylidene)-4H-1,2,4-triazol-4-amines. The procedure occurs by cleavage of the N-N bond in the N-(alkylidene)-4H-1,2,4-triazol-4-amines and activation of an aryl C-H bond in the substituted pyridines. This is the first example of the preparation of imidazopyridine derivatives by using pyridines as the substrates by transition-metal-catalyzed C-H functionalization. This method should provide a novel and efficient strategy for the synthesis of other nitrogen heterocycles.
authors.affiliation: Key Laboratory of Bioorganic Phosphorus Chemistry and Chemical Biology (Ministry of Education), Department of Chemistry, Tsinghua University, Beijing 100084 (P.R. China), Fax: (+86) 10-62781695.
authors.forename: Jipan
authors.initials: J
authors.lastname: Yu
authors.forename: Yunhe
authors.initials: Y
authors.lastname: Jin
authors.forename: Hao
authors.initials: H
authors.lastname: Zhang
authors.forename: Xiaobo
authors.initials: X
authors.lastname: Yang
authors.forename: Hua
authors.initials: H
authors.lastname: Fu
mesh_terms: D002384:Catalysis; D003300:Copper / Q000737:chemistry*; D010084:Oxidation-Reduction; D011725:Pyridines / Q000138:chemical synthesis* / Q000737:chemistry
chemical_list: D011725:Pyridines; D003300:Copper; C001439:imidazo(1,2-a)pyridine
keywords: CH activation; copper; homogeneous catalysis; nitrogen heterocycles; oxidation