Iron-Promoted Construction of Indoles via Intramolecular Oxidative C–N Coupling of 2-Alkenylanilines Using Persulfate
作者:Menglan Wang、Yudong Li、Qing-An Wu、Shuping Luo、Yuehui Li
DOI:10.1055/s-0037-1611521
日期:2019.8
K2S2O8/FeF2 system offers a direct and benign syntheticroute to 3-arylindoles and it is applicable to a wide range of substitutedindoles including drug intermediates. Indole scaffold synthesis relies primarily on oxidative C–H amination of N-protected alkenylanilines for C–N intramolecular cyclization reactions. Herein, for the first time, without N-protection, various readily prepared 2-alkenylanilines were
抽象的 吲哚支架的合成主要依靠N保护的链烯基苯胺的C–H氧化胺化作用进行C–N分子内环化反应。在此,在没有催化N的情况下,通过在催化量的FeF 2存在下使用K 2 S 2 O 8作为氧化剂,将各种容易制备的2-烯基苯胺以高收率转化成所需的吲哚产物。K 2 S 2 O 8 / FeF 2系统为3-芳基吲哚提供了直接而良性的合成途径,适用于包括药物中间体在内的各种取代的吲哚。 吲哚支架的合成主要依靠N保护的链烯基苯胺的C–H氧化胺化作用进行C–N分子内环化反应。在此,在没有催化N的情况下,通过在催化量的FeF 2存在下使用K 2 S 2 O 8作为氧化剂,将各种容易制备的2-烯基苯胺以高收率转化成所需的吲哚产物。K 2 S 2 O 8 / FeF 2系统为3-芳基吲哚提供了直接而良性的合成途径,适用于包括药物中间体在内的各种取代的吲哚。
Metal-free and regiospecific synthesis of 3-arylindoles
作者:Chuangchuang Xu、Wenlai Xie、Jiaxi Xu
DOI:10.1039/d0ob00317d
日期:——
arylhydrazine hydrochlorides and Fischer indolization. The organic base triethylamine plays a crucial role in the final elimination step in the Fischer indole synthesis, affording 3-arylindoles regiospecifically. The reaction features advantages of microwave acceleration, non-metal participation, short reaction time, organic acid-base co-catalysis, and broad substrate scope.
A practical protocol to synthesize 3-substituent-2-(azol-1-yl)indolederivatives has been developed via an electrochemical oxidative cross coupling process under mild conditions. This electro-oxidative C–N bond formation strategy tolerates a range of functional groups and is amenable to gram scale synthesis. Moreover, this method was applied to the late-stage functionalization of bioactive molecules
“On Water” Direct and Site-Selective Pd-Catalysed CH Arylation of (NH)-Indoles
作者:Lionel Joucla、Nelly Batail、Laurent Djakovitch
DOI:10.1002/adsc.201000512
日期:2010.11.22
communication describes the development of a versatile catalytic system based on palladium(II) acetate/bis(diphenylphosphino)methane [Pd(OAc)2/dppm] that works “on water” giving site-selective CH arylation of (NH)-indoles without protecting or directing groups. Remarkably, the control of regioselectivity was achieved by small changes in the “extra-catalytic” base/halide partners. These innovative methodologies
Pyridylmethylamine-Palladium Catalytic Systems: A Selective Alternative in the C−H Arylation of Indole
作者:Serge Perato、Benjamin Large、Qiao Lu、Anne Gaucher、Damien Prim
DOI:10.1002/cctc.201601275
日期:2017.2.6
A highly efficient pyridylmethylamine‐Pd alternative catalytic system for the C−H arylation of indole was explored. Variously substituted aryl groups were regio‐ and chemoselectively installed at the indole nucleus by using barium hydroxide as the base. The method was found to be efficient even in the presence of hindered coupling partners and Pd‐reactive bonds.