Senem Akkoç
Süleyman Demirel University, Turkey
Title: Catalytic activities in the suzuki–miyaura cross-coupling reaction of unsymmetrical substituted benzimidazolium salts and their palladium complexes
Biography
Biography: Senem Akkoç
Abstract
For the formation of C-C bonds in the midst of the organoboron compounds and organic halides, Pd-catalyzed Suzuki-Miyaura cross-coupling reaction is a very important method. The aryl chlorides have usually been used as substrates for this reaction due to practical and economic reasons. A series of unsymmetrical substituted new benzimidazolium salts and their PEPPSI type palladium complexes, which have become popular in recent years, were synthesized in order to improving more reactive catalysts. For the synthesis of salts, firstly, 1-alkylbenzimidazole was prepared from benzimidazole (1 mmol), alkyl chloride (1 mmol) and potassium hydroxide (1 mmol) in ethyl alcohol (60 mL). Alkyl halide (1 mmol) was added to a solution of DMF containing 1-alkylbenzimidazole (1 mmol) and the reaction mixture was refluxed for 24 h. On the other hand, PEPPSI type Pd-NHC complexes were prepared from PdCl2 (1 mmol), benzimidazolium salts (1 mmol) and K2CO3 (5 mmol) in 3-chloropyridine (3 mL). The structures of all compounds were characterized by suitable spectroscopic and analytic methods. All compounds were tested as catalysts in Suzuki-Miyaura reaction, which was done using following reagents; organoborane derivatives, aryl halides, synthesized compounds, base and DMF/H2O. The reaction mixture was sustained at different temperatures and times for obtaining optimum conditions. According to the obtained results, they especially were quite effective in the coupling of 4-chlorotoluene with 4-tertbutylphenylboronic acid.