2 - (3 - halogen-phenyl) pyridine derivatives for preparing method
The invention discloses a preparation method of a 2-(3-halogen phenyl) pyridine derivative. The preparation method comprises the following steps: dissolving 2-phenylpyridine or substitutive 2-phenylpyridine (I) and N-halogenated butyl diimide (II) into a
-
Paragraph 0036; 0038; 0039
(2017/08/25)
Directed meta-Selective Bromination of Arenes with Ruthenium Catalysts
A Ru-catalyzed direct C?H 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 radical-mediated bromination when NBS is utilized as the bromine source. This type of transformation has opened up a new direction for the radical non-ipso functionalization of metal with regard to future C?H activation development that would allow the remote functionalization of aromatic systems.
Copper-catalyzed aromatic C-H bond halogenation using lithium halides as halogenating reagents
The copper-catalyzed C-H halogenation of 2-aryl-pyridines containing a variety of electron-withdrawing and electron-donating substituents was described. It is worth noting that cheap and easy-to-handle lithium halides were utilized as the halogen sources. Georg Thieme Verlag Stuttgart · New York.