Iodine–ammonium acetate promoted reaction between 2-aminopyridine and aryl methyl ketones: a novel approach towards the synthesis of 2-arylimidazo[1,2-a]pyridines
作者:Dilpreet Kour、Rajni Khajuria、Kamal K. Kapoor
DOI:10.1016/j.tetlet.2016.08.058
日期:2016.10
I2–NH4OAc was found to be an efficient system for the metal-free synthesis of diversely substituted imidazo[1,2-a]pyridines 3a–r from 2-aminopyridine 1 and aryl methyl ketones 2a–r in one pot. 2-Arylimidazo[1,2-a]pyridines 3a–r were obtained in good to excellent yields via in situ generation of an Ortoleva–King intermediate (pyridinium iodide), followed by NH4OAc-assisted cyclization.
发现I 2 -NH 4 OAc是一种有效的系统,可在一锅中由2-氨基吡啶1和芳基甲基酮2a - r进行无取代合成咪唑并[1,2- a ]吡啶3a - r的无金属合成。通过原位生成Ortoleva-King中间体(碘化吡啶),然后进行NH 4 OAc辅助环化,可以很好地获得2-Arylimidazoazo [1,2- a ]吡啶3a – r。