作者:Christopher J. Teskey、Andrew Y. W. Lui、Michael F. Greaney
DOI:10.1002/anie.201504390
日期:2015.9.28
transition‐metal‐catalyzed, meta‐selectiveCHbromination procedure is reported. In the presence of catalytic [Ru(p‐cymene)Cl2}2], tetrabutylammonium tribromide can be used to functionalize the metaCH bond of 2‐phenylpyridine derivatives, thus affording difficult to access products which are highly predisposed to further derivatization. We demonstrate this utility with one‐pot bromination/arylation and
报道了过渡金属催化的间位选择性C - H 溴化过程的第一个例子。在催化[Ru(p-伞花烃)Cl 2 } 2 ]存在下,三溴化四丁基铵可用于官能化2-苯基吡啶衍生物的间位C - H键,从而提供难以获得的产物,该产物非常容易进一步衍生化。我们通过一锅式溴化/芳基化和溴化/烯基化程序证明了这种实用性,可在一步中分别提供间芳基化和间烯基化产物。
Directed<i>meta</i>-Selective Bromination of Arenes with Ruthenium Catalysts
Ru‐catalyzed direct CH activation/meta‐bromination of arenes bearing pyridyl, pyrimidyl, and pyrazolyl directing groups has been developed. A series of bromo aryl pyridines and pyrimidines have been synthesized, and further coupling reactions have also been demonstrated for a number of representative functionalized arenes. Preliminary mechanistic studies have revealed that this reaction may proceed through
heterogeneous ruthenium catalyst for meta‐selective C−H functionalizations, which enabled remote halogenations with excellent site selectivity and ample scope. The versatile heterogeneous Ru@SiO2 catalyst was broadly applicable and could be easily recovered and reused, which set the stage for the direct fluorescent labeling of purines. In contrast to palladium, rhodium, iridium, or cobalt complexes, solely
The first electrochemical transition-metal-catalyzed meta-C−H functionalization has been accomplished, affording the positionally selective bromination product in an undivided cell by the catalysis of readily available RuCl3⋅3 H2O with aqueous HBr as the brominating agent.
第一个电化学过渡金属催化的间位-C−H 官能化已经完成,通过容易获得的 RuCl 3 ⋅3 H 2 O 和水性 HBr 作为溴化剂的催化作用,在未分割的电池中提供了位置选择性的溴化产物。