分享一篇C-H活化领域大牛于金泉教授在Nature上的最新大作,在此篇文章中于金泉教授首次实现了远程的C-H活化,具有非常重要的意义。同期Nature上对此篇文章进行了点评!欢迎大家下载!
题目:Activation of remote meta-C–H bonds assisted by an end-on template
作者:Dasheng Leow,1, 2 Gang Li,1, 2 Tian-Sheng Mei1 & Jin-Quan Yu1
期刊:Nature Volume: 486, Pages: 518–522
发表时间:Date published: (28 June 2012)
DOI: doi:10.1038/nature11158
页数:5页
摘要:
Functionalization of unactivated carbon–hydrogen (C–H) single bonds is an efficient strategy for rapid generation of complex molecules from simpler ones. However, it is difficult to achieve selectivity when multiple inequivalent C–H bonds are present in the target molecule. The usual approach is to use σ-chelating directing groups, which lead to ortho-selectivity through the formation of a conformationally rigid six- or seven-membered cyclic pre-transition state. Despite the broad utility of this approach, proximity-driven reactivity prevents the activation of remote C–H bonds. Here we report a class of easily removable nitrile-containing templates that direct the activation of distal meta-C–H bonds (more than ten bonds away) of a tethered arene. We attribute this new mode of C–H activation to a weak ‘end-on’ interaction15 between the linear nitrile group and the metal centre. The ‘end-on’ coordination geometry relieves the strain of the cyclophane-like pre-transition state of the meta-C–H activation event. In addition, this template overrides the intrinsic electronic and steric biases as well as ortho-directing effects with two broadly useful classes of arene substrates (toluene derivatives and hydrocinnamic
本部分内容设定了隐藏,需要回复后才能看到