C-H bond functionalization of arylpyrimidines catalyzed by an in situ generated ruthenium(II) carboxylate system and the construction of tris(heteroaryl)-substituted benzenes

摘要

A ruthenium(II) carboxylate catalyst, generated in situ from [RuCl _2(p-cymene)]_2 and 1-phenyl-1-cyclopentanecarboxylic acid (PCCA) in the presence of K_2CO_3, allowed activation of the C-H bond in phenyl-substituted pyrimidines and their direct functionalization with both electron-deficient and electron-rich aryl halides. The scope of this process can be extended to the use of heteroaryl bromides and less reactive aryl chlorides. This Ru~(II)-PCCA complex constitutes a better catalytic system in comparison to other carboxylates. A simple and effective method was developed for a high-yielding phenylpyrimidinemetalation-arylation with an Ru~(II) catalytic system.