title: Rh(III)-catalyzed C-H activation/cyclization of indoles and pyrroles: divergent synthesis of heterocycles.
abstract: We report herein a new strategy of the Rh(III)-catalyzed C-H activation/cyclization of indoles and pyrroles, for the divergent synthesis of privileged heterocycles. A simple derivation of indoles and pyrroles to N-carboxamides with oxidative bidentate directing group could enable rhodacycle formation and late-stage redox-neutral cyclization with alkynes, alkenes and diazo compounds, for access to five- and six-membered fused heterocycles, such as pyrimido[1,6-a]indol-1(2H)-one, 3,4-dihydropyrimido[1,6-a]indol-1(2H)-one, and 1H-imidazo[1,5-a]indol-3(2H)-ones. Kinetic isotope effect study was conducted, and a plausible mechanism was proposed. Furthermore, this protocol was applied to concise synthesis of 5-HT3 receptor antagonist in gram-scale.
authors.affiliation: Institute of Materia Medica and College of Pharmaceutical Sciences, Zhejiang University , Hangzhou 310058, China.
authors.forename: Yan
authors.initials: Y
authors.lastname: Zhang
authors.forename: Jing
authors.initials: J
authors.lastname: Zheng
authors.forename: Sunliang
authors.initials: S
authors.lastname: Cui
mesh_terms: D002384:Catalysis; D003500:Cyclization; D006571:Heterocyclic Compounds / Q000138:chemical synthesis* / Q000737:chemistry*; D007211:Indoles / Q000737:chemistry*; D015394:Molecular Structure; D009942:Organometallic Compounds / Q000737:chemistry*; D011758:Pyrroles / Q000737:chemistry*; D012238:Rhodium / Q000737:chemistry*
chemical_list: D006571:Heterocyclic Compounds; D007211:Indoles; D009942:Organometallic Compounds; D011758:Pyrroles; D012238:Rhodium