W. Purcell et al., THE SUBSTITUTION KINETICS OF THE AQUA LIGAND BY CYANIDE IONS IN [RU(TPPS)(CO)(H2O)](4-), Transition metal chemistry, 21(1), 1996, pp. 77-80
The reaction between the title compound, phonatophenyl)porphynatoaquac
arbonylruthenate(II), [Ru(TPPS)(CO)(H2O)](4-), and CN- revealed that o
nly the aqua ligand is substituted even in the presence of a large exc
ess of the nucleophile. The pK(a1) was spectrophotometrically determin
ed as 13.4(5) (at 33.2 degrees C) and kinetically as 13.44(5) (at 33.6
degrees C). The rate of aqua substitution was determined as 89(4)M(-1
) s(-1) at 35.1 degrees C and the activation enthalpy and entropy as 5
5.44(1) kJ mol(-1) and - 27.90(4)5 K-1 mol(-1), respectively.