Characterization and application of FerroZine iron reagent as a ferrous iron indicator

Reaction of [RuCl 2 ( p -cymene)] 2 with the tridentate N - N ′- N ligands, 2,6-pyridyl-diimines, led to substitution of p -cymene. The resulting complexes, believed to be coordinatively unsaturated, exhibit efficient activity for the epoxidation of cyclohexene in the presence of iodosobenzene (PhIO): the complexes formed initially take up donor molecules such as acetonitrile to achieve hexacoordination. The molecular structure for one of these, (acetonitrile){2,6-bis[1-(4-methoxyphenylimino)ethyl]pyridine}dichlororuthenium(II), 2 , has been determined by X-ray diffraction. The immediate coordination sphere is a distorted octahedron with trans chloride atoms and a short Ru–N(py) (1.906 A) bond.

Ruthenium(II) complexes with 2,6-pyridyl-diimine ligands: synthesis, characterization and catalytic activity in epoxidation reactions

Initial state and transition state solvation in inorganic reactions

The kinetics of Fe(II) complexation by Ferrozine in seawater

1,2,4,6-Tetraphenylpyridinium acetate as a new anion precipitant

The kinetics of the reactions of the complex tris[3-(2-pyridyl)-5,6-bis(4-Phenylsulphonato)-1,2,4-triazine]iron(II) in acid soloution, and with hydroxide, cynide, and peroxodisulphate ions, and hydrogen peroxide, have been investigated. The dependence of the observed rate constants on reagent concentration has been established for the reactions in acid, and with hydroxide and peroxodisulphate ions, at 35·0 ° C. For the reaction with cyanide ions, the rate law has been established and, from measured rate constants over a range of cyanide-ion concentrations and over the temperature range 25·3–44·1 °C, activation parameters both for cyanide-ion attack and for complex dissociation have been estimated. The variation of the rate of cyanide-ion attack with solvent composition has been determined for ethanol–water mixtures containg up to 30% ethanol. Patterns of reactivity for this complex are compared with those previously established for other low-spin iron(II) chelate complexes.

Kinetics of aquation of the complex tris[3-(2-pyridyl)-5,6-bis(4-phenylsulphonato)-1,2,4-triazine]iron(II) and its reactions with hydroxide, cyanide, and peroxodisulphate ions

Rate laws and rate constants are reported for reactions of several low-spin iron(II) complexes with hydroxide ion in methanol-water solutions. The dependence of the form of the rate law and of reactivity on ligand type and on substituent nature is discussed. The pattern of reactivity for a range of compounds with hydroxide ion in methanol-water mixtures is compared with the reactivity pattern for analogous reactions in dimethyl sulphoxide-water mixtures.

Reactions of low-spin iron(II) complexes with hydroxide ion in aqueous methanol: the effect of ligand on rates of reaction

Preparations of iron(II) complexes of bi-, tri-, quadri-, quinque-, and sexi-dentate Schiff bases are reported. The Schiff-base ligands are derived from pyridine-2-carbaldehyde, phenyl 2-pyridyl ketone, pyridine-2,6-dicarb-aldehyde. or 2,6-diacetylpyridine, and appropriate amines. All these complexes aquate in acid solution, and react with cyanide to give ternary iron(II)–cyanide–Schiff-base complexes. The kinetics of aquation of several of these Schiff-base complexes, and the kinetics of cyanide attack at all the complexes, are described, and reactivities are compared with those for analogous reactions of other iron(II) di-imine complexes. Solvent effects on the re-activity with cyanide of one of the complexes of the sexidentate Schiff bases in a range of binary aqueous mixtures are discussed.

Kinetics of reactions of Schiff-base complexes of iron(II). Part 6. The preparation and kinetics of reactions of complexes of multidentate ligands

Rate constants are reported for the aquation of the title complex [Fe(5NO2-phen)3]2+ in a series of binary aqueous mixtures at 298.1 K as a function of the concentration of added KBr or [NBu4]Br. The co-solvents are acetone, dimethyl sulphoxide, acetonitrile, and t-butyl alcohol. In each system the first-order rate constant increases when [NBu4] Br is added but decreases when KBr is added. The results are used to show that salt effects on this reaction are determined to a large extent by the size of the ion, although certain changes in the pattern of kinetic data particularly for t-butyl alcohol mixtures show that hydration and solvation interactions play some part in determining the overall trend.

Effects of added potassium bromide and tetra-n-butylammonium bromide on the kinetics of aquation of tris(5-nitro-1,10-phenanthroline)iron(II) in various binary aqueous mixtures

Rate constants are reported and discussed for several substitutions of inorganic complexes in ethylene carbonate (1,3-dioxolan-2-one) + water and in propylene carbonate (4-methyl-1,3-dioxolan-2-one) + water solvent mixtures. The reactions include aquation ofcis- and oftrans-[Co(en)2Cl2]+, aquation oftrans-[Cr(OH2)4Cl2]+, bromide substitution at [Pd(Et4dien)Cl]+, thiourea substitution atcis-[Pt(4-NCpy)2Cl2], and aquation and cyanide attack at [Fe(X-phen)3]2+ cations.

Kinetics of substitution reactions of transition metal complexes in 1,3-dioxolan-2-one + water and 4-methyl-1,3-dioxolan-2-one + water solvent mixtures

Fikry M. Mekhail

Papers

Kinetics of aquation of the complex tris[3-(2-pyridyl)-5,6-bis(4-phenylsulphonato)-1,2,4-triazine]iron(II) and its reactions with hydroxide, cyanide, and peroxodisulphate ions

Reactions of low-spin iron(II) complexes with hydroxide ion in aqueous methanol: the effect of ligand on rates of reaction

Kinetics of reactions of Schiff-base complexes of iron(II). Part 6. The preparation and kinetics of reactions of complexes of multidentate ligands

Effects of added potassium bromide and tetra-n-butylammonium bromide on the kinetics of aquation of tris(5-nitro-1,10-phenanthroline)iron(II) in various binary aqueous mixtures

Kinetics of substitution reactions of transition metal complexes in 1,3-dioxolan-2-one + water and 4-methyl-1,3-dioxolan-2-one + water solvent mixtures