NBS mediated one-pot regioselective synthesis of 2,3-disubstituted imidazo[1,2- a ]pyridines and their unambiguous characterization through 2D NMR and X-ray crystallography
作者:Ranjana Aggarwal、Gulshan Singh、Dionisia Sanz、Rosa M. Claramunt、M. Carmen Torralba、M. Rosario Torres
DOI:10.1016/j.tet.2016.04.072
日期:2016.7
A simple and mild protocol towards the regioselective synthesis of 1-aryl/heteroaryl-1-(2-methylimidazo[1,2-a]pyridin-3-yl)methanones has been developed by one-pot condensation of 2-aminopyridine with 1,3-diketones involving the intermediacy of 2-bromo-1,3-diketones formed in situ from 1,3-diketones using N-bromosuccinimide (NBS) in DCM by stirring at room temperature. The structure of the regioisomer
通过2-氨基吡啶与1的一锅缩合反应,开发了一种简单温和的方法,用于区域选择性合成1-芳基/杂芳基-1-(2-甲基咪唑并[1,2 - a ]吡啶-3-基)甲酮。在室温下使用N-溴琥珀酰亚胺(NBS)在DCM中搅拌由1,3-二酮就地形成的2-溴-1,3-二酮的中间体1,3-二酮。区域异构体的结构已通过严格的多核NMR [(1 H– 13 C)HMBC,(1 H– 13 C)HMQC,(1 H– 15 N)HMBC]光谱学和X射线晶体学研究得到了明确确认。