Hu Haipeng, Liu Yangbin, Guo Jing, Lin Lili, Xu Yali, Liu Xiaohua, Feng Xiaoming
Key Laboratory of Green Chemistry & Technology, Ministry of Education, College of Chemistry, Sichuan University, Chengdu 610064, P. R. China.
Chem Commun (Camb). 2015 Mar 4;51(18):3835-7. doi: 10.1039/c4cc10343b.
An asymmetric inverse-electron-demand hetero-Diels-Alder reaction between o-quinone methides and azlactones to generate potentially pharmacological active dihydrocoumarins has been achieved efficiently by using a chiral N,N'-dioxide-Sc(III) complex as the catalyst. The desired products were obtained in high yields with excellent enantioselectivities and diastereoselectivities (up to 94% yield, 96% ee and >19 : 1 dr) under mild reaction conditions. A concerted reaction pathway was confirmed by Operando IR and control experiments.
通过使用手性N,N'-二氧化物- Sc(III)配合物作为催化剂,邻醌甲基化物与恶唑烷酮之间的不对称逆电子需求杂环狄尔斯-阿尔德反应已高效实现,可生成具有潜在药理活性的二氢香豆素。在温和的反应条件下,以高收率、优异的对映选择性和非对映选择性(高达94%的收率、96%的对映体过量和大于19:1的非对映体比例)获得了所需产物。通过原位红外光谱和对照实验证实了协同反应途径。