Trio Catalysis Merging Enamine, Brønsted Acid, and Metal Lewis Acid Catalysis: Asymmetric Three-Component Aza-Diels-Alder Reaction of Substituted Cinnamaldehydes, Cyclic Ketones, and Arylamines
作者:Yongming Deng、Siddhartha Kumar、Kraig Wheeler、Hong Wang
DOI:10.1002/chem.201406569
日期:2015.5.18
phosphoric acid, and Y(OTf)3, enables the combination of enamine catalysis with both hard metal Lewis acid catalysis and Brønsted acid catalysis for the first time. Using this catalyst system, a three‐component aza‐Diels–Alder reaction of substituted cinnamaldehyde, cyclic ketone, and arylamine is carried out with high chemo‐ and enantioselectivity, affording a series of optically active 1,4‐dihydropyridine
由芳基胺,BINOL衍生的磷酸和Y(OTf)3组成的三重催化剂体系,首次使烯胺催化与硬质金属路易斯酸催化和布朗斯台德酸催化结合起来。使用这种催化剂体系,可以以高化学和对映选择性进行取代的肉桂醛,环酮和芳胺的三组分氮杂-狄尔斯-阿尔德反应,得到一系列光学活性的1,4-二氢吡啶(DHP)衍生物。以91–99% ee和59–84%的产率获得。还获得了具有良好对映选择性和中等产率的带有手性季碳中心的DHP(三个实例)。还进行了初步的机械研究。