Palladium-Catalyzed Asymmetric Cycloadditions of Vinylcyclopropanes and in Situ Formed Unsaturated Imines: Construction of Structurally and Optically Enriched Spiroindolenines
作者:Ze-Shui Liu、Wen-Ke Li、Tai-Ran Kang、Long He、Quan-Zhong Liu
DOI:10.1021/ol503383x
日期:2015.1.2
vinyl cyclopropane and α,β-unsaturated imines generated in situ from aryl sulfonyl indoles is reported. The reaction proceeds with high diastereoselectivity to provide the optically enriched spirocyclopentane-1,3′-indolenines in up to 74% yield and with up to 97% ee, which contains an all-carbon quaternary center and two tertiary stereocenters. The reaction involves a first conjugate addition of the
报道了钯催化的(3 + 2)乙烯基环丙烷和由芳基磺酰基吲哚就地生成的α,β-不饱和亚胺的环加成反应。该反应以高非对映选择性进行,以高达74%的收率和高达97%的ee提供光学富集的螺环戊烷-1,3'-吲哚胺,其包含全碳四元中心和两个叔立体中心。该反应包括将两性离子π-烯丙基铝络合物的碳阴离子从乙烯基环丙烷的第一共轭加成到原位形成的不饱和亚胺上,然后将钯催化的吲哚的分子内C 3-烯丙基化。