Dinuclear ruthenium(II) bipyridine complexes having non-symmetric α,α′-diimine based neutral bridging ligands. Synthesis, spectroscopic and electrochemical properties
DSpace at IIT Bombay
View Archive InfoField | Value | |
Title |
Dinuclear ruthenium(II) bipyridine complexes having non-symmetric α,α′-diimine based neutral bridging ligands. Synthesis, spectroscopic and electrochemical properties
|
|
Creator |
CHAKRABORTY, SOMA
MUNSHI, PRADIP LAHIRI, GOUTAM KUMAR |
|
Subject |
electrochemical properties
electrolytes acetonitrile |
|
Description |
A group of three dinuclear ruthenium(II) complexes of the type [(bpy)2RuII(L)RuII(bpy)2](ClO4)4·2H2O, 1a–1c [bpy=2,2′-bipyridine, L=bridging ligand, NpC5H4CH=Ni–(R)–Ni=CHC5H4Np; R=none, 1a; R=–C6H4–, 1b; R=–CH2–C6H4–CH2–, 1c] have been synthesized and characterized. The complexes are essentially diamagnetic and behave as 1:4 electrolytes in acetonitrile solution. The mass of the molecular ion for the complex 1a and the geometry of the complexes 1 in solution have been assessed by fast atom bombardment (FAB) mass spectrometry and 1H/13C NMR spectroscopy, respectively. Complexes 1 display three metal-to-ligand charge-transfer (MLCT) transitions in the visible region, where the lowest energy MLCT transition is considered to be a dπ(RuII)→π*(L) transition. The other two higher energy MLCT transitions are believed to be dπ(RuII)→π*(bpy) transitions. Highly intense ligand-based π→π* transitions are observed in the UV region. In acetonitrile solvent, complexes 1 show one quasi-reversible two-electron oxidation process near 1.5 V vs. Ag/AgCl, due to simultaneous one-electron oxidations [ruthenium (III)⇌ruthenium(II)] of both of the ruthenium centers in 1 and multiple reductions in the range −0.5–−2.7 V vs. Ag/AgCl, due to successive reductions of the coordinated bridging ligand, L, as well as bipyridine. The chemically and electrochemically generated oxidized trivalent congeners of 1 are unstable at room temperature.
|
|
Publisher |
Elsevier
|
|
Date |
2009-04-03T09:09:30Z
2011-11-25T20:43:02Z 2011-12-26T13:08:32Z 2011-12-27T05:56:29Z 2009-04-03T09:09:30Z 2011-11-25T20:43:02Z 2011-12-26T13:08:32Z 2011-12-27T05:56:29Z 1999 |
|
Type |
Article
|
|
Identifier |
Polyhedron 18(10), 1437-1444
0277-5387 http://dx.doi.org/10.1016/S0277-5387(99)00003-0 http://hdl.handle.net/10054/1138 http://dspace.library.iitb.ac.in/xmlui/handle/10054/1138 |
|
Language |
en
|
|