Brønsted Acid-Catalyzed Decarboxylative Redox Amination: Formation of <i>N</i>-Alkylindoles from Azomethine Ylides by Isomerization
作者:Hui Mao、Sichang Wang、Peng Yu、Huiqing Lv、Runsheng Xu、Yuanjiang Pan
DOI:10.1021/jo102218v
日期:2011.2.18
decarboxylative redox amination involving aldehydes with 2-carboxyindoline for the synthesis of N-alkylindoles is described. The decarboxylative condensations of aldehydes with 2-carboxyindoline produce azomethine ylides in situ, which then transform into N-alkylindoles by isomerization.
Tunable Hydride Transfer in the Redox Amination of Indoline with Aldehyde: An Attractive Intramolecular Hydrogen-Bond Effect
作者:Hui Mao、Runsheng Xu、Jieping Wan、Zhengyang Jiang、Cuirong Sun、Yuanjiang Pan
DOI:10.1002/chem.201001896
日期:2010.12.3
Hydride hijacked by “hydrogen”! N‐Alkylindoles and N‐alkylindolines were obtained in the redox amination of indoline with aldehyde, which was tuned by a hydrogen‐bond effect. Salicylaldehyde gave the indoline‐type product via intermolecular hydride transfer, while other aromatic aldehydes gave the indole‐type product via intramolecular hydride transfer.
An efficient and convenient palladium-catalyzed C–H bond oxidative sulfenylation of indoles and related electron-rich heteroarenes with arylboronicacids and elementalsulfur has been described. This procedure provides a useful and direct approach for the assembly of a wide range of structurally diverse 3-sulfenylheteroarenes with moderate to excellent yields from simple and readily available starting
A copper-mediated 2,3-difunctionalization of indoles to afford 3-halogenated 2,3′-biindoles is described herein. The protocol uses readily available feedstocks and a naturally abundant copper catalyst system, which allows the regioselective formation of C–C and C–X (X = Cl & Br) bonds in one single operation. Here the copper metal salt serves not only as a catalyst but also as a reactant to provide
The first highly enantioselective hydrogenation of simple indoles was developed with a Brønstedacid as an activator to form the iminium intermediate in situ, which was hydrogenated using Pd(OCOCF(3))(2)/(R)-H8-BINAP catalyst system with up to 96% ee. The present method provides an efficient route to enantioenriched 2-substituted and 2,3-disubstituted indolines.