Synthesis of six-membered spirooxindoles<i>via</i>a chiral Brønsted acid-catalyzed asymmetric intramolecular Friedel–Crafts reaction
作者:Hui-Xuan Chen、Yaqi Zhang、Yuyang Zhang、Xuefeng He、Zhen-Wei Zhang、Hao Liang、Wenhuan He、Xiaoding Jiang、Xiangmeng Chen、Liqin Qiu
DOI:10.1039/c8ra06710d
日期:——
and isatins, followed by a chiral phosphoric acid-catalyzed asymmetric intramolecular Friedel-Crafts reaction, a new class of valuable chiral 3′,4′-dihydro-2′H-spiro[indoline-3,1′-pyrrolo[1,2-a]pyrazin]-2-ones bearing a quaternary carbon stereocenter were successfully synthesized in good to excellent yields and with moderate to good enantioselectivities under mild reaction conditions.
通过N-氨基乙基吡咯和靛红的直接缩合,再通过手性磷酸催化的不对称分子内Friedel-Crafts反应,得到一类新的有价值的手性3',4'-二氢-2'H-螺[二氢吲哚-具有季碳立体中心的3,1'-吡咯并[1,2- a ]吡嗪]-2-酮在温和的反应条件下以良好至优异的收率和中等至良好的对映选择性成功合成。