Iodine-catalyzed synthesis of fused tetracyclic pyridazino[6,1-b]pyrrolo[1,2-a]quinazolin-9(1H)-one derivatives via a tandem reaction
作者:Wen-Ting Zhang、Wen-Wen Qiang、Chang-Sheng Yao、Xiang-Shan Wang
DOI:10.1016/j.tet.2016.03.018
日期:2016.4
presence of excess NaHCO3 is described. This is a tandem reaction to construct three new rings and a chiral quaternary carbon center in one-pot procedure. Two possible pathways in the formation of the second heterocycle are proposed, and they are confirmed by the key intermediates of pyrrolo[1,2-a]quinazolin-5(1H)-ones which are selectively obtained via controlling the ratio of base.
通过2-氨基苯甲酰肼与1,7-二氯庚烷反应合成哒嗪并[6,1- b ]吡咯并[1,2 - a ]喹唑啉-9(1 H)-一衍生物的简便且通用的方法描述了在过量的NaHCO 3存在下由碘催化的-4--1 。这是一种串联反应,只需一锅法即可构建三个新的环和一个手性季碳中心。提出了形成第二个杂环的两个可能途径,并通过吡咯并[1,2 - a ]喹唑啉-5(1 H)-的关键中间体证实,这些中间体是通过控制碱的比例选择性地获得的。