ISSN:
1572-901X
Source:
Springer Online Journal Archives 1860-2000
Topics:
Chemistry and Pharmacology
Notes:
Summary Rate constants are reported for substitution at the pentacyanoferrate(II) anions Fe(CN)5L3−, for L=4-cyanopyridine and 2-methylpyrazine, as a function of temperature at atmospheric pressure in methanol-water mixtures and as a function of pressure at 298.2 K in aqueous solution. Kinetic parameters (k, ΔH≠, ΔS≠, ΔV≠) are discussed in relation to other Fe(CN)5L3− complexes. Enthalpies of solution are reported for Na3[Fe(CN)5 (4CNpy)]5H2O, K3Fe(CN)6, 4-cyanopyridine, 3-methylpyridine, and 2-methylpyrazine in methanol-water mixtures, at 298.2 K. Solubilities are reported for thetris-ethylenediaminechromium(III) salts [Cr(en)3]Cl3, [Cr(en)3] [Fe(CN)6], and [Cr(en)3][Fe(CN)5(4CNpy)], and for 4-cyanopyridine, in methanol-water mixtures containing 0 to 80% methanol, at 298.2 K. Solvent effects on rate constants and on activation enthalpies for substitution at the [Fe(CN)5(4CNpy)]3− anion are analysed into initial state and transition state contributions. In the case both of rate constants and of activation enthalpies, very small effects of solvent composition on kinetic parameters result from large but almost equal effects on initial and transition states.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1007/BF00618572
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