Zhang Jianlin, Liu Xiaohua, Guo Songsong, He Changqiang, Xiao Wanlong, Lin Lili, Feng Xiaoming
Key Laboratory of Green Chemistry & Technology, Ministry of Education, College of Chemistry , Sichuan University , Chengdu , 610064 , People's Republic of China.
J Org Chem. 2018 Sep 7;83(17):10175-10185. doi: 10.1021/acs.joc.8b01425. Epub 2018 Jul 31.
The highly efficient enantioselective [4 + 2] cycloaddition of o-QMs with ortho-hydroxyphenyl-substituted α,β-unsaturated compounds was realized by using a chiral N, N'-dioxide-Sc(III) complex as catalyst. A variety of chiral chromane derivatives with three continuous stereocenters were obtained in excellent results (up to 99% yield, >19:1 dr, and 99% ee) under as low as 0.005-1 mol % catalyst loading. Besides, a catalytic cycle with a possible transition state model was proposed to elucidate the origin of the chirality.
通过使用手性N，N'-二氧化物- Sc(III)配合物作为催化剂，实现了邻醌甲基化物与邻羟基苯基取代的α，β-不饱和化合物的高效对映选择性[4 + 2]环加成反应。在低至0.005 - 1 mol%的催化剂负载量下，获得了多种具有三个连续立体中心的手性色满衍生物，产率优异（高达99%），非对映选择性大于19:1，对映体过量值为99%。此外，还提出了一个具有可能过渡态模型的催化循环，以阐明手性的起源。
