title: Synthesis of tri- and tetrasubstituted pyrazoles via Ru(II) catalysis: intramolecular aerobic oxidative C-N coupling.
abstract: An unprecedented ruthenium(II)-catalyzed intramolecular oxidative C-N coupling method has been developed for the facile synthesis of a variety of synthetically challenging tri- and tetrasubstituted pyrazoles. Dioxygen gas is employed as the oxidant in this transformation. The reaction demonstrates excellent reactivity, functional group tolerance, and high yields.
authors.affiliation: Department of Pharmacology and Pharmaceutical Sciences, School of Medicine, Tsinghua University, Beijing 100084, China.
authors.forename: Jiantao
authors.initials: J
authors.lastname: Hu
authors.forename: Shi
authors.initials: S
authors.lastname: Chen
authors.forename: Yonghui
authors.initials: Y
authors.lastname: Sun
authors.forename: Jing
authors.initials: J
authors.lastname: Yang
authors.forename: Yu
authors.initials: Y
authors.lastname: Rao
mesh_terms: D002384:Catalysis; D007700:Kinetics; D015394:Molecular Structure; D058451:Oxidative Coupling; D011720:Pyrazoles / Q000737:chemistry*; D012428:Ruthenium / Q000737:chemistry*
chemical_list: D011720:Pyrazoles; D012428:Ruthenium