The synthesis of 3-pyrazinyl-imidazo[1,2-a]pyridines from a vinyl ether
摘要:
A new method has been developed for the synthesis of 3-pyrazinyl-imidazo[1,2-a]pyridines. 2-Chloro-6[(Z)-2-ethoxyethenyl]pyrazine was treated with N-bromosuccinimide in dioxane-water to generate the 2-bromo-2-(6-chloropyrazin-2-yl)-1-ethoxyethanol intermediate. In a subsequent one-pot step, optional treatment with various 2-aminopyridines provided the cyclized 3-pyrazinyl-imidazo[1,2-a]pyridines in 31-76% yields. (C) 2010 Elsevier Ltd. All rights reserved.