Cycloisomerization of 2-Alkynylanilines to Indoles Catalyzed by Carbon-Supported Gold Nanoparticles and Subsequent Homocoupling to 3,3′-Biindoles
作者:Jesus E. Perea-Buceta、Tom Wirtanen、Otto-Ville Laukkanen、Mikko K. Mäkelä、Martin Nieger、Michele Melchionna、Nina Huittinen、Jose A. Lopez-Sanchez、Juho Helaja
DOI:10.1002/anie.201305579
日期:2013.11.4
Elevated by the support: 2‐Alkynyl aniline cycloisomerization to indole is catalyzed by cationic Au NPs on a carbon support. Electroneutral and rich 2‐aryl indoles are further converted into 3,3′‐biindoles by oxidative homocoupling that is readily catalyzed by the Au NPs on carbon, and exclusively but also somewhat sluggishly by the carbon support.
Brønsted Acid Catalyzed Cascade Reactions of 2-[(2-Aminophenyl)ethynyl]phenylamine Derivatives with Aldehydes: A New Approach to the Synthesis of 2,2′-Disubstituted 1<i>H</i>,1′<i>H</i>-3,3′-Biindoles
An unusual Brønsted acid catalyzed cascade reaction of 2-[(2-aminophenyl)ethynyl]phenylamine derivatives with aryl(heteroaryl)aldehydes to afford an efficient alternative entry into 2,2′-disubstituted-1H,1′H-3,3′-biindoles under metal-free conditions is reported.
Iron-catalyzed oxidative homo-coupling of indoles via C–H cleavage
作者:Tianmin Niu、Yuhong Zhang
DOI:10.1016/j.tetlet.2010.10.088
日期:2010.12
A new method for the homo-coupling of indoles has been developed by the use of FeCl3 as catalyst and molecular oxygen as the only oxidant. The protocol provides a practical and straightforward approach toward 3,3'-biindolyls. (C) 2010 Elsevier Ltd. All rights reserved.