Copper-catalyzed aromatic C–H bond halogenation with lithium halides under aerobic conditions
作者:Song Mo、Yamin Zhu、Zengming Shen
DOI:10.1039/c3ob40185e
日期:——
A concise and practical Cu-catalyzed protocol for the preparation of chloro- and bromoarenes via C–H bond activation has been developed. The advantages of this strategy are the employment of cheap Cu(NO3)2·3H2O, LiX and O2, and its compatibility with both electron-donating and electron-withdrawing substituents on aryl rings.
Cu-Mediated Direct Aryl CH Halogenation: a Strategy to Control Mono- and Di-Selectivity
作者:Zhi-Jun Du、Lian-Xun Gao、Ying-Jie Lin、Fu-She Han
DOI:10.1002/cctc.201300734
日期:2014.1
A protocol for the copper‐mediated directarylCHhalogenation is presented. Highly selective mono‐ and di‐halogenations are achieved by using acyl hypohalites, generated in situ from the readily available carboxylic acid and N‐halosuccinimides (NXS; X=Br and Cl) as powerful halogenating reagents. The correct choice of carboxylic acid additives and solvents is essential for both high yield and selectivity
提出了铜介导的直接芳基CH卤化的方案。通过使用酰基次卤酸盐来实现高度选择性的单卤化和二卤化,酰基次卤酸盐是由现成的羧酸和N-卤代琥珀酰亚胺(NXS; X = Br和Cl)原位生成的,作为强力卤化试剂。正确选择羧酸添加剂和溶剂对于高收率和选择性都至关重要。因此,使用廉价的铜催化剂和从容易负担得起且易于处理的羧酸和NXS(X = Br和Cl)原位生成酰基次卤酸盐卤化试剂的新策略为实际应用提供了优势。
Tris-NHC-propagated self-supported polymer-based Pd catalysts for heterogeneous C–H functionalization
imidazolium-containing mesoporous coordination polymer and organic polymer-based platforms were successfully exploited to develop single-site heterogenized Pd–NHC catalysts for oxidative arene/heteroarene C–H functionalization reactions. The catalysts were efficient in directed arene halogenation, and nondirected arene and heteroarene arylation reactions. High catalytic activity, excellent heterogeneity and
A new strategy for catalytic functionalization of C-H bonds by means of electrochemical oxidation is described. Combination of palladium-catalyzed aromatic C-H bond cleavage and halogenation with electrochemically generated halonium ions enables highly efficient, selective halogenations of aromatic compounds in a green-sustainable manner. The required reagents for this reaction are an arene and an
Copper(ii)-catalyzed ortho-functionalization of 2-arylpyridines with acyl chlorides
作者:Wenhui Wang、Changduo Pan、Fan Chen、Jiang Cheng
DOI:10.1039/c0cc05557c
日期:——
Copper-catalyzed ortho-benzoxylation of 2-arylpyridine sp2 C–H bonds with acyl chloride is described. Notably, switching the base from t-BuOK to Li2CO3 causes chlorination of the C–H bond to take place.