Construction of cyclopenta[b]pyran-2-ones viachemoselective (3 2) cycloaddition between 2-pyrones and vinyl cyclopropanes
Construction of cyclopenta[b]pyran-2-ones viachemoselective (3 2) cycloaddition between 2-pyrones and vinyl cyclopropanes
复制标题
通过 2-吡喃酮和乙烯基环丙烷之间的化学选择性 (3 2) 环加成反应构建环戊[b]吡喃-2-酮
DOI：
10.1039/d0qo00049c
复制
发表时间：
2020
影响因子：
5.4
通讯作者：
李志成
中科院分区：
文献类型：
--
作者：
梁学锋;叶伟健;Waygen Thor;Lantian Sun;Bo wang;何述钟;Yuen-Kit Cheng;李志成
报道了2-吡喃酮与乙烯基环丙烷直接（3 + 2）环加成合成环戊并[B]吡喃-2-酮的方法。在Pd_2（dba）_3/dppe催化下，一系列2-吡喃酮与乙烯基环丙烷发生化学选择性（3 + 2）环加成反应，高产率（78-96%）得到环戊[B]吡喃-2-酮.环加合物的反式/顺式比率已优化至10：1。 这种环加成的机制已经通过计算研究得到了合理化。
A method for synthesising cyclopenta[b]pyran-2-ones through direct (3 + 2) cycloaddition between 2-pyrones and vinyl cyclopropanes is described. In the presence of Pd2(dba)3/dppe in toluene, a series of 2-pyrones undergo chemoselective (3 + 2) cycloaddition with vinyl cyclopropanes and afford cyclopenta[b]pyran-2-ones in high yields (78–96%). The trans/cis ratio of the cycloadducts has been optimised up to 10 : 1. The proposed mechanism of this cycloaddition has been rationalised by computational studies.