Chemistry of ruthenium with some dioxime ligands. Syntheses, structures and reactivities
Journal
Polyhedron
Journal Volume
20
Journal Issue
3-4
Pages
327-335
Date Issued
2001
Author(s)
Abstract
Reaction of two dioxime ligands, viz. dimethylglyoxime (H2dmg) and diphenylglyoxime (H2dpg). (abbreviated in general as H2L. where H stands for the oxime protons) with [Ru(PPh3)3Cl2] in 1:1 mole ratio affords complexes of type [Ru{PPh3)2(H2L)Cl2]. Structure of the [Ru(PPh3)2(H2dpg)Cl2] complex has been solved by X-ray crystallography. The coordination sphere around ruthenium, is N2P2Cl2 with the two PPh3 ligands in frans and the two chlorides in cis positions. Reaction of the dioxime ligands with [Ru(PPh3)3Cl2] in 2:1 mole ratio in the presence of a base affords complexes of type [Ru(PPh3)2(HL)2]. Structure of the [Ru(PPh2(Hdmg)2] complex has been solved by X-ray crystallography. The coordination sphere around ruthenium is N4P2 with the two PPh3 ligands in trans positions. Reaction of the [Ru(PPh3)2H2dpg)Cl2 complex with a group of bidentate acidic ligands, viz. picolinic acid (Hpic), quinolin-8-ol (Hq) and 1-nitroso-2-naphthol (Hnn), (abbreviated in general as HL', where H stands for the acidic proton) in the presence of a base affords complexes of type [Ru(PPh3)2(H2dpg)(L')]+ isolated as perchlorate salts. All the complexes are diamagnetic (low-spin d6, S = 0) and in dichloromethane solution show several intense MLCT transitions in the visible region. Cyclic voltammetry on all the complexes shows a reversible ruthenium(II)-ruthenium(III) oxidation within 0.36-0.98 V versus SCE followed by a quasi-reversible ruthenium(III)-ruthenium(IV) oxidation within 0.94- 1.60 V versus SCE. © 2001 Elsevier Science B.V.
SDGs
Type
journal article