Catalytic Asymmetric Dearomatization by Visible-Light-Activated [2+2] Photocycloaddition
Catalytic Asymmetric Dearomatization by Visible-Light-Activated [2+2] Photocycloaddition
复制标题
DOI：
10.1002/anie.201802891
复制
发表时间：
2018-05-22
影响因子：
16.6
通讯作者：
Meggers, Eric
中科院分区：
文献类型：
--
作者：
Hu, Naifu;Jung, Hoimin;Meggers, Eric
报道了一种新的催化不对称脱芳构化的方法，该方法通过苯并呋喃和苯并噻吩的可见光活化[2 + 2]光环加成反应，得到了包括四元立体中心在内的最多四个立体中心的手性三环结构。苯并呋喃和苯并噻吩在2-位上用螯合的N-酰基吡唑部分官能化，这允许与可见光可活化的手性铑刘易斯酸催化剂配位。计算分子模拟揭示了不寻常的区域选择性的起源，并确定杂环中的杂原子是区域控制的关键。
A novel method for the catalytic asymmetric dearomatization by visible-light-activated [2+2] photocycloaddition with benzofurans and one example of a benzothiophene is reported, thereby providing chiral tricyclic structures with up to four stereocenters including quaternary stereocenters. The benzofurans and the benzothiophene are functionalized at the 2-position with a chelating N-acylpyrazole moiety which permits the coordination of a visible-light-activatable chiral-at-rhodium Lewis acid catalyst. Computational molecular modeling revealed the origin of the unusual regioselectivity and identified the heteroatom in the heterocycle to be key for the regiocontrol.