TiCl4/t-BuNH2 as the sole catalyst for a hydroamination-based Fischer indole synthesis
摘要:
A system comprising TiCl4 and t-BuNH2 acts as a catalyst for highly regioselective hydroamination reactions of alkynes using hydrazines and at the same time a Lewis acid in the transformation of the generated hydrazones into indole derivatives, while a 1,3-diyne is converted to pyrroles using the same precatalyst. (C) 2004 Elsevier Ltd. All rights reserved.
Heteroannulation of arynes with N-aryl-α-aminoketones for the synthesis of unsymmetrical N-aryl-2,3-disubstituted indoles: an aryne twist of Bischler–Möhlau indole synthesis
Reaction of 2-(trimethylsilyl)aryl triflates 1 with N-aryl-alpha-amino ketones 2 afforded N-aryl-2,3-disubstituted indoles in good to excellent yields with complete control of the substitution patterns. This methodology allowed for the first time a one-stepsynthesis of unsymmetrical 2,3-dialkyl substituted indoles in a regiospecific manner.
TiCl4/t-BuNH2 as the sole catalyst for a hydroamination-based Fischer indole synthesis
作者:Lutz Ackermann、Robert Born
DOI:10.1016/j.tetlet.2004.10.160
日期:2004.12
A system comprising TiCl4 and t-BuNH2 acts as a catalyst for highly regioselective hydroamination reactions of alkynes using hydrazines and at the same time a Lewis acid in the transformation of the generated hydrazones into indole derivatives, while a 1,3-diyne is converted to pyrroles using the same precatalyst. (C) 2004 Elsevier Ltd. All rights reserved.