Asymmetric [4+2] cycloaddition of azlactones with dipolar copper–allenylidene intermediates for chiral 3,4-dhydroquinolin-2-one derivatives
作者:Bing-Bing Sun、Qing-Xian Hu、Jia-Ming Hu、Jie-Qiang Yu、Jun Jia、Xing-Wang Wang
DOI:10.1016/j.tetlet.2019.06.041
日期:2019.7
provides optically active 3,4-dihydroquinolin-2-ones in high yields with good enantioselectivities and diastereoselectivities. In this transformation, the chiral dipolar copper–allenylidene intermediates are kinetically generated via decarboxylative ethynyl benzoxazinanones, followed by the attack of the enolate azlactones to form enantiomerically enriched 3,4-dihydroquinolin-2-one structures.
本文开发了一种pybox-copper催化的乙炔基苯并恶嗪酮酮与丁二酮的对映选择性脱羧[4 + 2]环加成反应,可提供高产率的旋光3,4-二氢喹啉-2-酮,具有良好的对映选择性和非对映选择性。在这种转化中,手性偶极铜-亚烯基中间体是通过脱羧乙炔基苯并恶嗪酮酮动力学生成的,然后烯醇盐a酸酯形成对映异构体富集的3,4-二氢喹啉-2-酮结构。