An unusual, very rapid, stopped-flow base hydrolysis of the aß-anti-[Cr(picdien)Cl](ClO4)2[(picdien) = 1,9-bis(2-pyridyl)-2,5,8-triazanonane]
Por:
Ugalde-Saldivar V.M., Sosa-Torres M.E., Tobe M.L.
Publicada:
1 ene 1996
Resumen:
The base hydrolysis of the complex ??-anti-[Cr(Picdien)Cl](ClO4)2 has been studied in phosphate and ?-collidine buffer solutions over the pH range 7.5-6.5, at 25°C and ? = 0.100 mol-1 dm3. The calculated second-order rate constant, kOH, was found to be 1.05±0.07 × 104 mol-1 dm3 s-1, the greatest reported, so far, for linear polydentate amine ligands. The activation parameters found are as follows: ?H? = 65±2 kJ mol-1 and a ?S? = 52 + 6 J K-1 mol-1. The second-order rate constant obtained from a borax buffer solution over the pH range 8.5-10.4 by the stopped-flow technique was found to be kOH = 1.32±0.03 × 104 mol-1 dm3 s-1 at 25°C, which is in good agreement with that obtained at lower pH values, confirming the linearity of the base hydrolysis over wide pH ranges. Copyright © 1996 Elsevier Science Ltd.
Filiaciones:
Ugalde-Saldivar V.M.:
Div. Estud. Posgrado Fac. de Quim., Univ. Nac. Auton. de México, Ciudad Universitaria, Coyoacán 04510, Mexico
Sosa-Torres M.E.:
Div. Estud. Posgrado Fac. de Quim., Univ. Nac. Auton. de México, Ciudad Universitaria, Coyoacán 04510, Mexico
Tobe M.L.:
Christopher Ingold Laboratories, University College London, 20 Gordon Street, London WC1H 0AJ, United Kingdom
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