The synthesis of substituted indolo[1,2-a]quinoline-5(6H)-ones starting from 1-(2-ethynylphenyl)-1H-indoles is presented. The method involves gold-catalyzed oxidation of the triple bond followed by an acid-promoted intramolecular cyclization at the indole C-2 position.
[EN] REACTION METHOD FOR SECONDARY AMINE AND O-DIIODOBENZENE<br/>[FR] PROCÉDÉ DE RÉACTION POUR AMINE SECONDAIRE ET O-DIIODOBENZÈNE<br/>[ZH] 一种仲胺与邻二碘苯的反应方法
Synthesis of 5-Iodopyrrolo[1,2-<i>a</i>]quinolines and Indolo[1,2-<i>a</i>]quinolines via Iodine-Mediated Electrophilic and Regioselective 6-<i>endo</i>-<i>dig</i> Ring Closure
The endo-cyclic ring closure of 1-(2-(substituted ethynyl)pheny1)-1H-pyrroles 3a-t and 1-(2-(substituted ethynyl)phenyl)-H-indole 4a-o mediated by Lewis acid (I-2) under mild conditions afforded substituted 5-iodopyrrolo[1,2-a]quinolines 5a-t and 5-iodoindolo[1,2-a]quinolines 6a-o in good to excellent yields. The reaction shows selective C-C bond formation on the more electrophilic alkynyl carbon, resulting in the regioselective 6-endo-dig-cyclized product. Iodo derivatives of pyrrolo- and indoloquinolines allow functional group diversification on the quinoline nucleus, which proves to be highly advantageous for structural and biological activity assessments.
Benzotriazole: an efficient ligand for the copper-catalyzed N-arylation of indoles
作者:Akhilesh Kumar Verma、Jaspal Singh、Richard C. Larock
DOI:10.1016/j.tet.2009.07.050
日期:2009.10
A general, efficient, and inexpensive method for the N-arylation of indoles using a catalytic system derived from Cul and benzotriazole is reported. Selective mono N-arylation of indoles with ortho-di-haloarenes has also been successfully achieved in good yields using this protocol. (C) 2009 Published by Elsevier Ltd.