Luksamee Sahavisit and Kanidtha Hansongnern

pp. 751 - 759

Abstract

5-Chloro-2-(phenylazo)pyridine (Clazpy) was synthesized as a new bidentate ligand, containing an
azo moiety. Its structure was similarly to 2-(phenylazo)pyridine (azpy) but the hydrogen atom on the fifth
position on the pyridine ring was replaced by a chlorine atom. The [Ru(Clazpy)₃](PF₆) complex was prepared
from the reaction between ctc-[Ru(Clazpy)₂Cl₂] with the Clazpy ligand in methanol. The [Ru(Clazpy)₃](PF₆)₂
complex was characterized by elemental analysis, IR and ¹H NMR data. Electronic absorption spectra in
various solvents exhibit strong metal-to-ligand charge transfer (MLCT) bands at 490-550 nm. Results from
cyclic voltammetry show that the bidentate Clazpy ligand is a better π-acceptor than azpy in order to
stabilize Ru(II) center.