title: Metal-free catalyzed oxidative trimerization of indoles by using TEMPO in air: a biomimetic approach to 2-(1H-indol-3-yl)-2,3'-biindolin-3-ones.
abstract: A simple, convenient and efficient metal-free catalyzed oxidative trimeric reaction of indoles toward a variety of 2-(1H-indol-3-yl)-2,3'-biindolin-3-one derivatives in moderate to excellent yields has been developed. This transformation proceeds via a tandem oxidative homocoupling reaction by using TEMPO in air as an environmentally benign oxidant. This methodology provides an alternative approach for the direct generation of all-carbon quaternary centers at the C3 position of indoles.
authors.affiliation: Department of Chemistry and Chemical Engineering, Gannan Normal University, Huanjin Campus, Ganzhou, Jiangxi 341000, PR China.
authors.forename: Wen-Bing
authors.initials: WB
authors.lastname: Qin
authors.forename: Qiong
authors.initials: Q
authors.lastname: Chang
authors.forename: Yun-Hong
authors.initials: YH
authors.lastname: Bao
authors.forename: Ning
authors.initials: N
authors.lastname: Wang
authors.forename: Zheng-Wang
authors.initials: ZW
authors.lastname: Chen
authors.forename: Liang-Xian
authors.initials: LX
authors.lastname: Liu
mesh_terms: D032701:Biomimetics / Q000379:methods*; D002384:Catalysis; D003497:Cyclic N-Oxides / Q000737:chemistry*; D007211:Indoles / Q000138:chemical synthesis / Q000737:chemistry*; D008958:Models, Molecular; D016877:Oxidants / Q000737:chemistry*; D010084:Oxidation-Reduction
chemical_list: D003497:Cyclic N-Oxides; D007211:Indoles; D016877:Oxidants; C057812:indoline; C003959:TEMPO