Stereoselective synthesis of spirooxindole derivatives using an organocatalyzed tandem Michael–Michael reaction
作者:Huicai Huang、Manisha Bihani、John C.-G. Zhao
DOI:10.1039/c5ob02348c
日期:——
A highly efficient stereoselective method for the synthesis of functionalized spirooxindole derivatives with three stereogenic centers was realized through an organocatalytic tandem Michael–Michael reaction. By employing (S)-α,α-diphenylprolinol trimethylsilyl ether as the catalyst and N,N′-bis[3,5-bis(trifluoromethyl)phenyl]thiourea as the cocatalyst, the reaction between N-tritylisatylidenemalononitriles
通过有机催化串联迈克尔-迈克尔反应,实现了一个高效的立体选择性方法,该方法可合成具有三个立体生成中心的功能化螺氧杂吲哚衍生物。以(S)-α,α-二苯基脯氨醇三甲基甲硅烷基醚为催化剂,N,N'-双[3,5-双(三氟甲基)苯基]硫脲为助催化剂,N-三苯甲基赖基亚甲基丙二腈与(E)-7-烷基-7-氧杂庚酮5-烯类化合物可产生所需的螺恶灵吲哚产物,收率好(76-95%),非对映选择性(高达97:3 dr)和对映选择性(高达98%ee),通过分子内还原性胺化反应可将立体异构体选择性地转化为螺[吲哚啉-3,8'-异喹啉]衍生物。