[4 + 2]-Annulation of MBH-Acetates of Acetylenic Aldehydes with Imidazoles/Benzimidazoles To Access Imidazo[1,2-<i>a</i>]pyridines/Benzimidazo[1,2-<i>a</i>]pyridines
作者:Chada Raji Reddy、Amarender Goud Burra
DOI:10.1021/acs.joc.9b01118
日期:2019.7.19
developed to construct diversely substituted imidazo[1,2-a]pyridines and benzimidazo[1,2-a]pyridines in good to excellent yield. The advantage of this unique [4 + 2]-annulation lies in the employment of readily accessible starting materials, Morita–Baylis–Hillman acetates of acetylenic aldehydes as C4 synthons, and simple imidazoles or benzimidazoles as C2 synthons.
前所未有的一锅连续碱介导的烯丙基胺化/环异构反应的策略已经被开发来构造不同地取代的咪唑并[1,2一]吡啶和苯并咪唑并[1,2一]在良好吡啶以优良的产率。这种独特的[4 + 2]环状结构的优势在于使用了易于获取的起始材料,即乙炔醛的Morita–Baylis–Hillman乙酸盐作为C4合成子,以及简单的咪唑或苯并咪唑作为C2合成子。