Efficient in situ N-heterocyclic carbene palladium(ii) generated from Pd(OAc) 2 catalysts for carbonylative Suzuki coupling reactions of arylboronic acids with 2-bromopyridine under inert conditions leading to unsymmetrical arylpyridine ketones: synthesis, characterization and cytotoxic activities.

N , N -Substituted benzimidazole salts were successfully synthesized and characterized by 1 H-NMR, 13 C { 1 H} NMR and IR techniques, which support the proposed structures. Catalysts generated in situ were efficiently used for the carbonylative cross-coupling reaction of 2 bromopyridine with various boronic acids. The reaction was carried out in THF at 110 °C in the presence of K 2 CO 3 under inert conditions and yields unsymmetrical arylpyridine ketones. All N , N -substituted benzimidazole salts 2a-i and 4a-i studied in this work were screened for their cytotoxic activities against human cancer cell lines such us MDA-MB-231, MCF-7 and T47D. The N , N -substituted benzimidazoles 2e and 2f exhibited the most cytotoxic effect with promising cytotoxic activity with IC 50 values of 4.45 μg mL -1 against MDA-MB-231 and 4.85 μg mL -1 against MCF7 respectively.