One-Pot Protocol for the Synthesis of Imidazoles and Quinoxalines using<i>N</i>-Bromosuccinimide
作者:Sachin D. Pardeshi、Pratima A. Sathe、Kamlesh S. Vadagaonkar、Atul C. Chaskar
DOI:10.1002/adsc.201700900
日期:2017.12.11
N‐bromosuccinimide (NBS)‐mediated one‐pot, green, efficient and practical synthesis of substituted imidazoles and quinoxalines has been achieved by the reaction of styrenes with N‐arylbenzamidines and o‐phenylenediamines, respectively, in a water:1,4‐dioxane mixture. The reaction involves formation of an α‐bromo ketone as an intermediate in the presence of NBS and water, followed by condensation with
A simple route for the synthesis of imidazole derivatives via copper-catalyzed [3 + 2] cycloaddition reaction is described. This strategy has achieved high regioselectivity and used oxygen as an oxidant without the addition of expensive catalysts to provide moderate to good yields.
§ Authors contributed equally to this work. Abstract A copper-catalyzed expedient, practical, and straightforward approach for the one-pot three-component modular synthesis of multisubstituted imidazoles has been described by using arylacetic acids, N-arylbenzamidines, and nitroalkanes. The reaction involves simultaneous activation of C–H and N–H bonds of arylacetic acids and N-arylbenzamidines, respectively
We have successfully developed the I2-catalysed synthesis of substituted imidazole derivatives from amidines and ketones in good to excellent yields and 100% regioselectivity.
An efficient and facile approach to synthesize imidazoles from amidines and arylketone via oxidative coupling of sp(3) C-H bond and N-H bond is reported. This strategy exhibits high performance in terms of regioselectivity with moderate to high yields by using easily available materials, and provides an alternative method to synthesize multi-substituted imidazole skeletons. (C) 2014 Elsevier Ltd. All rights reserved.