Xiao Lei, Jin Lvnan, Zhao Yunbo, Guo Jing, Stephan Douglas W
Institute of Drug Discovery Technology, Ningbo University, Zhejiang, China.
Department of Chemistry, University of Toronto, Toronto, 80 St. George Street, Ontario M5S 3H6, Canada.
Chem Commun (Camb). 2023 Feb 9;59(13):1833-1836. doi: 10.1039/d2cc06744g.
Spirocyclopropane-oxindoles are key motifs in biologically active compounds and are versatile synthetic intermediates. Herein, we report a metal-free, B(CF) catalyzed cyclopropanation of 3-alkenyl-oxindoles with diazomethanes. This provides 25 variants of spirocyclopropane-oxindole derivatives. These spirocyclopropane-oxindole products were obtained in good to excellent yields (up to 99%) and high diastereoselectivities (up to 20 : 1 d.r.) under mild reaction conditions and could be performed on a gram scale.
螺环丙烷-氧化吲哚是生物活性化合物中的关键结构单元，也是通用的合成中间体。在此，我们报道了一种无金属、B(CF)催化的3-烯基-氧化吲哚与重氮甲烷的环丙烷化反应。这提供了25种螺环丙烷-氧化吲哚衍生物变体。这些螺环丙烷-氧化吲哚产物在温和的反应条件下以良好至优异的产率（高达99%）和高非对映选择性（高达20:1的非对映体比例）得到，并且可以进行克级规模的反应。
