Substituted 2-(2``-pyridyl)benzimidazole palladium(II) complexes as an efficient catalytic system for Suzuki--Miyaura cross-coupling reactions

Authors : MAHMUT ULUSOY, NURDAL ÖNCEL, Emine AYTAR

Pages : 1289-1299

View : 20 | Download : 7

Publication Date : 0000-00-00

Article Type : Research Paper

Abstract :A new series of $N,N$-type 2-insert ignore into journalissuearticles values(2`-pyridyl);benzimidazole ligands insert ignore into journalissuearticles values(\textbf{2A}$_{\mathbf{1}}$,\textbf{ 2A}$_{\mathbf{2}}$,\textbf{ 3B}$_{\mathbf{1}}$,\textbf{ 3B}$_{\mathbf{2}}$,\textbf{ 3B}$_{\mathbf{3}}$, and\textbf{ 4C}$_{\mathbf{1}});$ and their Pdinsert ignore into journalissuearticles values(II); complexes insert ignore into journalissuearticles values(\textbf{5A}$_{\mathbf{1}}$,\textbf{ 5A}$_{\mathbf{2}}$,\textbf{ 6B}$_{\mathbf{1}}$,\textbf{ 6B}$_{\mathbf{2}}$,\textbf{ 6B}$_{\mathbf{3}}$, and\textbf{ 7C}$_{\mathbf{1}});$ were prepared and characterized by conventional spectroscopic methods and elemental analyses. The incorporation of $N$-coordinated benzimidazole complexes of palladium gave high catalytic activity in the Suzuki--Miyaura coupling of aryl halides substrates. After determining the best active catalyst as \textbf{5A}$_{\mathbf{1}}$, bearing the mesityl substituent on the benzimidazole ring with the Pdinsert ignore into journalissuearticles values(II); ion, optimization studies were carried out via changing the substrate, base, time, atmosphere, and the effect of water. The DMF:H$_{2}$O insert ignore into journalissuearticles values(4/1); and Cs$_{2}$CO$_{3}$ as base were found to be critical for the efficiency of the reaction yield insert ignore into journalissuearticles values(100{\%});.
Keywords : Palladium, 2 2` pyridyl, benzimidazole, aryl halides, phenylboronic acid, Suzuki Miyaura