Catalyst-Controlled Nickel-Catalyzed Intramolecular <i>endo</i>-Selective C–H Cyclization of Benzimidazoles with Alkenes
作者:Zi-Jian Liu、Jiang-Fei Li、Feng-Ping Zhang、Xue-Tao Xu、Mengchun Ye
DOI:10.1021/acs.orglett.2c04012
日期:2023.1.20
Compared with the widely explored exo-selective C–H cyclization, transition metal-catalyzed endo-selective C–H cyclization of benzimidazoles with alkenes has been a formidable challenge. Previous efforts mainly rely on substrate-controlled methods, rendering the product complexity restricted. Herein we report a catalyst-controlled method to facilitate endo-cyclization, in which a bulky N-heterocyclic
与广泛探索的外向选择性C-H环化相比,过渡金属催化的苯并咪唑与烯烃的内向选择性C-H环化一直是一项艰巨的挑战。以前的努力主要依靠基板控制的方法,使产品的复杂性受到限制。在此,我们报告了一种促进内环化的催化剂控制方法,其中大体积的N-杂环卡宾配体和t BuOK碱基启用的 Ni-Al 双金属催化剂证明对内环选择性至关重要。