title: Mn(III)-mediated formal [3+3]-annulation of vinyl azides and cyclopropanols: a divergent synthesis of azaheterocycles.
abstract: Mn(III)-mediated formal [3+3]-annulation has been developed using readily available vinyl azides and cyclopropanols with a wide range of substituents. Vinyl azides were successfully applied as a three-atom unit including one nitrogen to prepare pyridines and δ-lactams by the reactions with monocyclic cyclopropanols as well as to construct 2-azabicyclo[3.3.1] and 2-azabicyclo[4.3.1] frameworks with bicyclic cyclopropanols, bicyclo[3.1.0]hexan-1-ols, and bicyclo[4.1.0]heptan-1-ols. These reactions were initiated by a radical addition of β-carbonyl radicals, generated by the one-electron oxidation of cyclopropanols with Mn(III), to vinyl azides to give iminyl radicals, which cyclized with the intramolecular carbonyl groups. In addition, application of the present methodology to a synthesis of the quaternary indole alkaloid, melinonine-E, was accomplished.
authors: Division of Chemistry and Biological Chemistry, School of Physical and Mathematical Sciences, Nanyang Technological University, Singapore 637371, Singapore.
authors: Yi-Feng
authors: YF
authors: Wang
authors: Kah Kah
authors: KK
authors: Toh
authors: Eileen Pei Jian
authors: EP
authors: Ng
authors: Shunsuke
authors: S
authors: Chiba
mesh_terms: D001372:Aza Compounds / Q000138:chemical synthesis*; D001386:Azides / Q000737:chemistry*; D004988:Ethers, Cyclic / Q000737:chemistry*; D006571:Heterocyclic Compounds / Q000138:chemical synthesis*; D008345:Manganese / Q000737:chemistry*; D008958:Models, Molecular
chemical_list: D001372:Aza Compounds; D001386:Azides; D004988:Ethers, Cyclic; D006571:Heterocyclic Compounds; C043657:cyclopropanol; D008345:Manganese