Cis-bis(bipyridine)ruthenium imidazole derivatives: A spectroscopic, kinetic, and structural study

Journal Article · Wed Dec 04 04:00:00 EST 1996 · Inorganic Chemistry

DOI:https://doi.org/10.1021/ic951434b· OSTI ID:451272

Reddy, K B; Emge, T J; Wishart, J F ^[1]

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1. State Univ. of New Jersey, Piscataway, NJ (United States); and others

The ruthenium bis(bipyridine) complexes cis-[Ru(bpy){sub 2}Im(OH{sub 2})]{sup 2+}, cis-[Ru(bpy){sub 2}(IM){sub 2}]{sup 2+}, cis-[Ru(bpy){sub 2}(N-Im){sub 2}]{sup 2+}, cis-[Ru(dmbpy){sub 2}Im(OH{sub 2})]{sup 2+}, cis-[Ru(dmbpy){sub 2}(N-Im)(OH{sub 2})]{sup 2+}(bpy = 2,2{prime}-bipyridine, dmbpy = 4,4{prime}-dimethyl-2,2{prime}-bipyridine, Im = imidazole, N-Im = N-methylimidazole), have been synthesized under ambient conditions in aqueous solution (pH 7). Their electrochemical and spectroscopic properties, absorption, emission, and lifetimes were determined and compared. The substitution kinetics of the cis-[Ru(bpy){sub 2}Im(OH{sub 2})]{sup 2+} complexes show slower rates and have lower affinities for imidazole ligands than the corresponding cis-[Ru(NH{sub 3}){sub 4}Im(OH{sub 2})]{sup 2+} complexes. The crystal structures of the monoclinic cis-[Ru(bpy){sub 2}(Im){sub 2}](BF{sub 4}){sub 2}, space group = P2{sub 1}/a, Z = 4, a = 11.344(1) {angstrom}, b = 17.499(3) {angstrom}, c = 15.114(3) {angstrom}, and {beta} = 100.17(1){degrees}, and triclinic cis-[Ru(bpy){sub 2}(N-Im)(H{sub 2}O)](CF{sub 3}COO){sub 2}{center_dot}H{sub 2}O, space group = P1, Z = 2, a = 10.432(4) {angstrom}, b = 11.995(3) {angstrom}, c = 13.912(5) {angstrom}, {alpha} = 87.03(3){degrees}, {beta} = 70.28(3){degrees}, and {gamma} = 71.57(2){degrees}, complexes show that these molecules crystallize as complexes of octahedral Ru(II) to two bidentate bipyridine ligands with two imidazole ligands or a water and an N-methylimidazole ligand cis to each other. The importance of these molecules is associated with their frequent use in the modification of proteins at histidine residues and in comparisons of the modified protein derivatives with these small molecule analogs.

• DOE Contract Number: FG02-93ER14356
• OSTI ID: 451272
• Journal Information: Inorganic Chemistry, Journal Name: Inorganic Chemistry Journal Issue: 25 Vol. 35; ISSN 0020-1669; ISSN INOCAJ
• Country of Publication: United States
• Language: English

Related Subjects

40 CHEMISTRY
ABSORPTION SPECTROSCOPY
BIPYRIDINES
CHEMICAL REACTION KINETICS
CRYSTAL STRUCTURE
ELECTROCHEMISTRY
EMISSION SPECTROSCOPY
IMIDAZOLES
MONOCLINIC LATTICES
RUTHENIUM COMPLEXES
STRUCTURAL CHEMICAL ANALYSIS
TRICLINIC LATTICES
X-RAY DIFFRACTION