Asymmetric Organocatalytic Quadruple Cascade Reaction of 2-Hydroxychalcone with Cinnamaldehyde for the Construction of Tetrahydro-6<i>H</i>-benzo[<i>c</i>]chromene Containing Five Stereocenters
作者:Lingyan Liu、Yunna Zhu、Kaimeng Huang、Bing Wang、Weixing Chang、Jing Li
DOI:10.1002/ejoc.201402159
日期:2014.7
An asymmetric organocatalytic quadruple cascade reaction was developed for the stable and sterically hindered 2-hydroxychalcones and substituted cinnamaldehydes. This process proceeded through an oxa-Michael–Michael–Michael–aldol condensation to afford highly functionalized tetrahydro-6H-benzo[c]chromene derivatives with high diastereoselectivity and enantioselectivity (>99 % ee). The structure of
为稳定和空间位阻的 2-羟基查尔酮和取代的肉桂醛开发了不对称有机催化四级联反应。该过程通过氧杂-迈克尔-迈克尔-迈克尔-羟醛缩合反应得到高度官能化的四氢-6H-苯并[c]色烯衍生物,具有高非对映选择性和对映选择性(>99%ee)。具有五个立体中心的加合物 4g 的结构通过单晶 X 射线衍射得到明确证实,有价值的质谱数据为所提出的反应机理提供了直接支持。