Release Time:2019-03-10  Hits:

Indexed by: Journal Article

Date of Publication: 2008-03-15

Journal: POLYHEDRON

Included Journals: SCIE

Volume: 27

Issue: 4

Page Number: 1168-1176

ISSN: 0277-5387

Key Words: ruthenium complex; dipyridylpyrazole derivatives; X-ray diffraction

Abstract: A mononuclear ruthenium complex [Ru(bpy)(2)(bpp)](PF6) (1) and its halogenated and nitro derivatives [Ru(bpy)(2)(Xbpp)](PF6) (bpy = 2,2'-bipyridine; bpp = 3,5-bis(2-pyridyl)pyrazole; X = Cl, 2; X = Br, 3; X = I, 4; X = NO2, 5) have been synthesized and characterized by H-1 NMR, C-13 NMR, HRMS, elemental analysis. Complexes 2-5 have been further confirmed by X-ray diffraction. Their UV-Vis and emission spectroscopies, electrochemical measurements and acid-base properties are described. The results presented here reveal that the introduction of Cl, Br, I and NO2 groups to the coordinated bpp(-) ligand makes the absorption and emission maxima of the parent complex 1 blue-shifted, the oxidation potential of the Ru-II/Ru-III couple increased and the pK(a) value decreased obviously. In addition, significant quenching of the emission by these groups is also observed. (C) 2008 Elsevier Ltd. All rights reserved.