Ruthenium complexes with Schiff base ligands containing
benz(othiazole/imidazole) moieties: Structural, electron spin resonance
and electrochemistry studies
Novel ruthenium(II/III) complexes of Schiff bases containing benzimidazole (bz) or benzothiazole (bs)
moieties were isolated: the diamagnetic ruthenium complex, cis-[RuIICl2(bzpy)(PPh3)2] (1) was formed
from the 1:1 M reaction between N-((pyridine-2-yl)methylene)-1H-benzimidazole (bzpy) and metal precursor,
trans-[RuCl2(PPh3)3]. The same metal precursor, when reacted with the benzimidazole-derived
Schiff bases [N-(2-hydroxybenzylidene)-benzothiazole (Hbsp) and N-(2-hydroxybenzylidene)-benzimidazole
(Hbzp)], afforded the paramagnetic ruthenium(III) complexes [RuCl(bsp)2(PPh3)] (2) and
trans-[RuCl(bzp)(PPh3)2] (3), respectively. These metal complexes were characterized via IR, mass and
UV–Vis spectroscopy, elemental analysis, single crystal XRD analysis as well as conductivity measurements.
Their redox properties were probed by voltammetry and accompanying UV–Vis spectroelectrochemistry
experiments. Structural features of complex 1 were further investigated by multinuclear (1H
and 31P) NMR spectroscopy