An efficient transition-metal-free synthesis of 1H-indazoles from arylhydrazones with montmorillonite K-10 under O2 atmosphere
作者:Jin Yu、Jin Woo Lim、Su Yeon Kim、Jimin Kim、Jae Nyoung Kim
DOI:10.1016/j.tetlet.2015.01.183
日期:2015.3
An efficient transition-metal-free synthetic method of 1H-indazoles has been developed. The reaction of arylhydrazones in the presence of montmorillonite K-10 in 1,2-dichlorobenzene at 130 degrees C afforded 1Hindazoles in good yields most likely via a sequential intramolecular nucleophilic cyclization and an aerobic oxidation pathway. (C) 2015 Elsevier Ltd. All rights reserved.
Synthesis of 1<i>H</i>-Indazoles and 1<i>H</i>-Pyrazoles via FeBr<sub>3</sub>/O<sub>2</sub> Mediated Intramolecular C–H Amination
作者:Tianshui Zhang、Weiliang Bao
DOI:10.1021/jo3026862
日期:2013.2.1
A new synthesis of substituted 1H-indazoles and 1H-pyrazoles from arylhydrazones via FeBr3/O-2 mediated C-H activation/C-N bond formation reactions is reported. The corresponding 1,3-diaryl-substituted indazoles and trisubstituted pyrazoles were obtained in moderate to excellent yields under mild conditions.