The first nickel-catalyzed C–H arylations and alkenylations of imidazoles with phenol and enol derivatives are described.
第一个镍催化的咪唑与酚和烯醇衍生物的C-H芳基化和烯基化反应被描述了。
Nickel-Catalyzed Efficient and Practical Suzuki−Miyaura Coupling of Alkenyl and Aryl Carbamates with Aryl Boroxines
作者:Li Xu、Bi-Jie Li、Zhen-Hua Wu、Xing-Yu Lu、Bing-Tao Guan、Bi-Qin Wang、Ke-Qing Zhao、Zhang-Jie Shi
DOI:10.1021/ol9029534
日期:2010.2.19
Suzuki−Miyaura coupling of unactivated alkenyl carbamates is described to construct polysubstituted olefins. The developed process is also suitable for heteroaromatic and even electron-richaromatic carbamates.
Palladium Catalyzed C–H Functionalization of <i>O</i>-Arylcarbamates: Selective <i>ortho</i>-Bromination Using NBS
作者:Alex John、Kenneth M. Nicholas
DOI:10.1021/jo300713h
日期:2012.7.6
cis-coordination of the amine. However, the amine adducts failed to undergo ortho-amination (C–N bond formation) under varied reaction conditions. Notably, the palladacycle 1d was found to react efficiently with N-iodosuccinimide (NIS) to yield the ortho-iodinated carbamate, 1e. More significantly, this reaction can be extended to a palladium-catalyzed ortho C–H bromination of aryl-O-carbamates even at 5 mol %
通过使各自的氨基甲酸酯与Pd(OAc)2在酸,CF 3 CO 2 H,CF 3 SO 3 H和p -TsOH存在下反应,合成了一系列衍生自O-苯基氨基甲酸酯的环金属化钯配合物。观察到palladacycles能配位胺和富电子的苯胺,但不能配位磺酰胺或羧酰胺。通过NMR光谱法(NOE)分析palladacycle 2b(2b · t Bu-NH 2)的t Bu-NH 2加合物显示出一种顺式-胺的配位。但是,在不同的反应条件下,胺加合物均无法进行邻氨基化(C–N键形成)。值得注意的是,发现palladacycle 1d与N-碘琥珀酰亚胺(NIS)有效反应,生成邻碘代氨基甲酸酯1e。更重要的是,即使在使用N-溴代琥珀酰亚胺(NBS)的Pd(OAc)2负载为5 mol%的情况下,该反应也可以扩展为钯催化的芳基-O-氨基甲酸酯的邻位C-H溴化反应。
Room-temperature Pd-catalyzed C–H chlorination by weak coordination: one-pot synthesis of 2-chlorophenols with excellent regioselectivity
作者:Xiuyun Sun、Yonghui Sun、Chao Zhang、Yu Rao
DOI:10.1039/c3cc47431c
日期:——
A room-temperature Pd(II)-catalyzed regioselective chlorination reaction has been developed for a facile one-pot synthesis of a broad range of 2-chlorophenols. The reaction demonstrates an excellent regioselectivity and reactivity for CâH chlorination. This reaction represents one of the rare examples of mild CâH functionalization at ambient temperature.
nickel-catalyzed cyanation of phenol derivatives with metal-free cyanating agents, aminoacetonitriles, is described. A nickel-based catalytic system consisting of a unique diphosphine ligand such as dcype or dcypt enables the cyanation of versatile phenol derivatives such as aryl carbamates and aryl pivalates. The use of aminoacetonitriles as a cyanating agent leads to an environmentally and easy-to-use method