Regioselective Synthesis of Indoles
<i>via</i>
Rhodium‐Catalyzed CH Activation Directed by an
<i>In‐Situ</i>
Generated Redox‐Neutral Group
作者:Krishnamoorthy Muralirajan、Chien‐Hong Cheng
DOI:10.1002/adsc.201400224
日期:2014.5.5
A regioselective synthesis of indoles from arylhydrazine hydrochlorides with alkynes and diethyl ketone catalyzed by a rhodium complex is described. A possible mechanism involving an in‐situ generated oxidizing directing group NNCR1R2 assisted ortho‐CHactivation and reductive elimination are proposed. The catalytic reaction is highly compatible with a wide range of functional arylhydrazines and
Palladium-Catalyzed Reaction of Arylamine and Diarylacetylene: Solvent-Controlled Construction of 2,3-Diarylindoles and Pentaarylpyrroles
作者:Xiaopeng Chen、Xihui Li、Ningning Wang、Jisong Jin、Ping Lu、Yanguang Wang
DOI:10.1002/ejoc.201200531
日期:2012.8
By choosing DMF and dioxane as solvent, skeletons of indoles and pyrroles were constructed from alkynes and amines in the presence of PdCl2, respectively. These Pd-catalyzed reactions were phosphane-free with high atom efficiency and could be conducted under mild basic conditions. The proposed mechanism for the selective formation of indoles and pyrroles in different solvents is also discussed in this
General and Efficient Synthesis of Indoles through Triazene-Directed C-H Annulation
作者:Chengming Wang、Huan Sun、Yan Fang、Yong Huang
DOI:10.1002/anie.201301742
日期:2013.5.27
Unprotected indoles are prepared with the title method, which has a wide scope for alkynes. Excellent regioselectivity was accomplished for aryl–alkyl and alkyl–alkyl disubstituted acetylenes. This reaction features an unusual 1,2 rhodium migration and ring‐contraction‐triggered NN bond cleavage. It allows rapid conversion of the reaction products into several functional molecules.