Binary diffusion coefficients of L-histidine methyl ester dihydrochloride in aqueous solutions
Rodrigo, M. M., Valente, A. J. M.[Artur J. M.], Barros, M. C. F.[Marisa C. F.], Verissimo, L. M. P.[Luis M. P.], Ramos, M. L., Justino, L. L. G.[Licinia L. G.], Burrows, H. D.[Hugh D.], Ribeiro, A. C. F.[Ana C. F.], Esteso, M. A.[Miguel A.]
The Taylor dispersion technique has been used for measuring mutual diffusion coefficients of L-histidine methyl ester as its dihydrochloride at T = 298.15 K and finite concentrations from (0.001 to 0.100) mol dm 3. On the basis of experimental mutual diffusion coefficients, the hydrodynamic radii, Rh, the diffusion coefficient at infinite dilution D0 and the dependence of thermodynamic factors, FT, on the concentration, have been estimated using the Onsager Fuoss equation. Further insight on the diffusion has been obtained from 1H and 13C NMR spectroscopy and DFT calculations, which suggest that the L-histidine methyl ester is present as its dication in acidic solution in a fully extended conformation, with considerable charge delocalization over the imidazolium ring. These experimental and computational results allow us to have a better understanding of the thermodynamic and kinetic behavior of this amino acid derivative in aqueous solutions.
Compounds
#
Formula
Name
1
C7H13Cl2N3O2
methyl L-histidinate dihydrochloride
2
H2O
water
Datasets
The table above is generated from the ThermoML associated json file (link above).
POMD and RXND refer to PureOrMixture and Reaction Datasets. The compound numbers are included in properties, variables, and phases, if specificied;
the numbers refer to the table of compounds on the left.