Department of Applied Chemistry, Jiang Xi Academic of Sciences, Nanchang, 330096, China.
Org Biomol Chem. 2021 Apr 14;19(14):3191-3198. doi: 10.1039/d1ob00214g. Epub 2021 Mar 23.
We report here that a series of bridged O,O-ketal fused spiro piperidone-cyclopropane derivatives 3 can be constructed with excellent yields and good diastereoselectivity by the one-pot reaction of 1-acylcyclopropanecarboxamides 1 with electron-deficient alkene 2a (EWG = CHO) via the domino process involving [4 + 2] annulation/intermolecular electrophilic addition/intramolecular cyclization. Furthermore, reactions of 1 with 2b/2c (EWG = CN, COOMe), leading to spiro piperidone-cyclopropane derivatives 4 or 5 by base catalyst selection, were also presented.
我们在这里报告，通过 1-酰基环丙甲酰胺 1 与缺电子烯烃 2a（EWG=CHO）的一锅反应，通过[4+2]环加成/分子间亲电加成/分子内环化的多米诺过程，可以以优异的收率和良好的非对映选择性构建一系列桥连 O,O-缩酮稠合螺哌啶-环丙烷衍生物 3。此外，还通过碱催化剂选择，展示了 1 与 2b/2c（EWG=CN，COOMe）的反应，得到螺哌啶-环丙烷衍生物 4 或 5。
