Palladium-Catalyzed Monoselective Halogenation of CH Bonds: Efficient Access to Halogenated Arylpyrimidines using Calcium Halides
作者:Bingrui Song、Xiaojian Zheng、Jun Mo、Bin Xu
DOI:10.1002/adsc.200900778
日期:2010.2.15
A wide variety of ortho-halogenated arylpyrimidines were prepared with high monoselectivity and functional-group tolerance by usingcalciumhalides as crucial halogenating agents and cupric trifluoroacetate as oxidant in the presence of air.
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.
The first example of a Cu-promoted ortho -chlorination of aryl C–H bonds by using TMSCCl 3 as chlorinating agent is reported. This reaction features a high selectivity toward monochlorination over dichlorination, compatibility with a variety of functional groups, and gram-scale synthesis.
报道了使用 TMSCCl 3 作为氯化剂对芳基 C-H 键进行 Cu 促进邻位氯化的第一个例子。该反应的特点是单氯化比二氯化具有高选择性、与多种官能团的相容性以及克级合成。
Salen-based hypercrosslinked polymer-supported Pd as an efficient and recyclable catalyst for C–H halogenation
In this work, we report the first use of a salen-based hypercrosslinked polymer-supportedPdcatalyst to carry out C-H halogenation. This catalyst can effectively catalyze C-H bromination and chlorination even better than its homogeneous counterpart Pd(OAc)2. It also showed excellent reusability without loss of catalytic activity for ten cycles. A broad substrate scope was explored and moderate to