Theoretical investigation on the mechanism of the N-heterocyclic carbene-catalyzed enantioselective

• 作 者: XiaokangGuo;DonghuiWei;MingshengTang;
• 机 构: The College of Chemistry and Molecular Engineering,Center of Computational Chemistry,Zhengzhou Unive
• 出 处: 第十二届全国量子化学会议
• 发表日期: 2014年期

　　Based on our previous work,[1,2,3,4] the computational study on the detailed mechanism of NHC-catalyzed enantioselective [4+2] annulation of oxidized enals and azodicarboxylates[5](Scheme 1)has been performed using density functional thoery.According to the calculated free energy profile,the [4+2] cycloaddition step is the enantioselectivity-determining step associated with the energy barriers of 8.71 kcal/mol for R configuration and 10.72 kcal/mol for S configuration respectively,which is in good agreement with the experimental results.Furthermore,the analysis of global reactivity index has been utilized to disclose the function of NHC catalyst in the [4+2] annulation.