Rh(III)-Catalyzed C–H Activation-Initiated Directed Cyclopropanation of Allylic Alcohols

We have developed a Rh­(III)-catalyzed diastereoselective [2+1] annulation onto allylic alcohols initiated by alkenyl C–H activation of N-enoxyphthalimides to furnish substituted cyclopropyl-ketones. Notably, the traceless oxyphthalimide handle serves three functions: directing C–H activation, oxidation of Rh­(III), and, collectively with the allylic alcohol, in directing cyclopropanation to control diastereoselectivity. Allylic alcohols are shown to be highly reactive olefin coupling partners leading to a directed diastereoselective cyclopropanation reaction, providing products not accessible by other routes.

我们开发了一种由N-烯氧基邻苯二甲酰亚胺的烯基C-H活化引发的、铑(III)催化的烯丙醇非对映选择性[2+1]环化反应，用于制备取代环丙基酮。值得注意的是，无残留的烯氧基邻苯二甲酰亚胺基团兼具三重功能：导向C-H活化、介导铑(III)的氧化循环，并且与烯丙醇协同，在环丙烷化过程中起到导向作用以调控非对映选择性。实验结果显示，烯丙醇作为活性极高的烯烃偶联底物，可参与该定向非对映选择性环丙烷化反应，所得产物无法通过其他合成路线获取。