Highly Enantioselective Iridium-Catalyzed Cascade Double Allylation Strategy: Synthesis of Pyrrolidinoindolines with an All-Carbon Quaternary Stereocenter
作者:Hua Tian、Fei Peng、Pengxiang Zhang、Haijun Yang、Hua Fu
DOI:10.1021/acs.orglett.9b03382
日期:2019.10.18
Highly enantioselective cascade double allylations of 1-alkyl-3-alkylindolin-2-imine hydrochlorides with (E)-but-2-ene-1,4-diyl dimethyl dicarbonate leading to tetrahydropyrrolo[2,3-b]indoles with an all-carbon quaternary stereocenter have been developed. This transformation was catalyzed by an iridium catalyst together with our developed chiral cyclic phosphoramidite ligand. The method shows some
1-烷基-3-烷基吲哚-2-亚胺盐酸盐与(E)-丁-2-烯-1,4-二甲基二碳酸二甲酯的高度对映选择性级联双烯丙基化反应,生成全部为四氢吡咯并[2,3- b ]吲哚-碳四元立体中心已经开发出来。铱催化剂与我们开发的手性环状亚磷酰胺配体一起催化了这种转变。该方法显示出一些优点,包括操作简单,反应快,非对映选择性和对映选择性优异。此外,用氢化二异丁基铝还原获得的产物使吡咯烷二氢吲哚具有三个手性中心,高收率,具有非对映选择性和对映选择性。