An efficient metal-free synthesis of 2-(pyrazin-2-yl)benzimidazoles from quinoxalinones and diaminomaleonitrile via a novel rearrangement
摘要:
A simple and highly efficient metal-free method for the synthesis of 2-(pyrazin-2-yl)benzimidazoles has been developed on the basis of the novel ring contraction of 3-aroyl- and 3-alkanoyiquinoxalin-2-ones with diaminomaleonitrile. (C) 2011 Elsevier Ltd. All rights reserved.