Traceless Directing Strategy: Efficient Synthesis of N-Alkyl Indoles via Redox-Neutral C–H Activation
作者:Chengming Wang、Yong Huang
DOI:10.1021/ol402523x
日期:2013.10.18
general protocol for the synthesis of N-alkyl indoles has been developed via a redoxneutral C–H activation strategy using a traceless nitroso directinggroup. A broad scope of substituted N-alkyl indoles has been prepared in good to excellent yields using a very simple Rh catalyst system in the absence of an external oxidant or any other additive. Good to excellent regioselectivity has been achieved for
One-Pot Tandem <i>ortho</i>-Naphthoquinone-Catalyzed Aerobic Nitrosation of <i>N</i>-Alkylanilines and Rh(III)-Catalyzed C–H Functionalization Sequence to Indole and Aniline Derivatives
作者:Tengda Si、Hun Young Kim、Kyungsoo Oh
DOI:10.1021/acs.joc.0c02776
日期:2021.1.1
The nitroso group served as a traceless directing group for the C–H functionalization of N-alkylanilines, ultimately removed after functioning either as an internal oxidant or under subsequent reducing conditions. The unique ability of o-NQ catalysts to aerobically oxidize the N-alkylanilines without using solvents and stoichiometric amounts of oxidants has rendered the new opportunity to develop the
Co(III)-catalyzed, internal and terminal alkyne-compatible indole synthesis protocol is reported herein. The N-amino (hydrazine) group imparts distinct, diverse reactivity patterns for directed C–H functionalization/cyclization reactions. Notable synthetic features include regioselectivity for a meta-substituted arylhydrazine, regioselectivity for a chain-branched terminalalkyne, formal incorporation of
halides using non-electrophilic amine sources for construction of indole scaffolds is reported. A palladium-catalyzed alkyne insertion/C-H activation/palladacycle amination via merger of three easily diversified components including iodoarenes, alkynes, and amines delivers indoles with different substitution patterns even in gram scales. By employing ortho-bromoanilines, a consecutive annulative π-extension
Assembly of Indole Cores through a Palladium-Catalyzed Metathesis of Ar–X σ-Bonds
作者:Farnaz Jafarpour、Mehran Ghasemi、Hamed Navid、Niloofar Safaie、Saideh Rajai-Daryasarei、Azizollah Habibi、Robert C. Ferrier
DOI:10.1021/acs.orglett.0c03611
日期:2020.12.18
We describe the development of a new method for construction of highly substituted indole scaffolds through the strategic utilizing of the metathesis of Ar-X σ-bonds based on the dynamic nature of palladium-based oxidative addition/reductive elimination. A suitable and simple catalytic system has provided an appropriate platform for a productive ligand exchange and consecutive carbopalladation/C–H