JOURNAL OF MOLECULAR STRUCTURE, sa.1359, ss.145473-145485, 2026 (SCI-Expanded, Scopus)
where NHC = 1-(2,3,5,6-tetramethylbenzyl)-3-(4-cyanobenzyl)benzimidazole-2-ylidene, 1,3-bis(4-cyanobenzyl)
benzimidazole-2-ylidene, or 1-(4-methylbenzyl)-3-(4-cyanobenzyl)benzimidazole-2-ylidene, and L = pyridine or
3-chloropyridine were prepared and characterized by elemental analysis, 1H and 13C NMR, and IR spectroscopy.
The molecular structure of dibromo[(1-(2,3,5,6-tetramethylbenzyl)-3-(4-cyanobenzyl)benzimidazole-2-ylidene]
pyridinepalladium(II) (2a) was determined by single-crystal X-ray diffraction analysis. The catalytic activity of
the Pd(II) complexes for Suzuki and Heck cross-coupling reactions was investigated in water-based solvent
mixtures. They were moderately active in the reaction of phenylboronic acid and aryl bromides. With 4-bromoacetophenone
and 4-bromobenzaldehyde, the desired products were obtained in 95% and 86% yields, respectively,
within 15 min at 80 ◦C using dibromo [1,3-bis(4-cyanobenzyl) benzimidazole-2-ylidene]pyridine
palladium(II), 2bIn the coupling of styrene with 4-bromoacetophenone, the product was obtained in 89% yield
after 5 h 80 ◦C using catalyst 2a. The antioxidant activities of the four compounds were also evaluated using
ABTS, OH and DPPH radical scavenging assays.