<abstract xmlns="http://www.w3.org/1999/xhtml">

L-alanine and β-alanine are important biological molecules and have zwitterion structure. In this study, L- alanine and β-alanine’s microscopic protonation constants and thermodynamic parameters (enthalpy, entropy, and free energy changes) for the proton–ligand systems of L-alanine methyl ester, β-alanine and β-alanine methyl ester have been determined at 5; 20; 35 °C, in ACN-water (25% ACN and 50% ACN (v/v)) mixtures at constant ionic strength of 0.1000 mol L–1 NaClO4 by potentiometric method. The results shown that, L-alanine and β-alanine’s microscopic protonation constants generally tend to decrease with temperature rise and their protonation reactions in ACN-water mixtures generally favor enthalpy-driven.
</abstract>

L-alanine and β-alanine are important biological molecules and have zwitterion structure. In this study, L- alanine and β-alanine’s microscopic protonation constants and thermodynamic parameters (enthalpy, entropy, and free energy changes) for the proton–ligand systems of L-alanine methyl ester, β-alanine and β-alanine methyl ester have been determined at 5; 20; 35 °C, in ACN-water (25% ACN and 50% ACN (v/v)) mixtures at constant ionic strength of 0.1000 mol L–1 NaClO4 by potentiometric method. The results shown that, L-alanine and β-alanine’s microscopic protonation constants generally tend to decrease with temperature rise and their protonation reactions in ACN-water mixtures generally favor enthalpy-driven.

Temperature dependence studies and microscopic protonation constants of L-alanine and β-alanine in acetonitrile – water mixtures

Ovidius University Annals of Chemistry

This work is licensed under the Creative Commons Attribution-NonCommercial-NoDerivatives 3.0 License.

L-alanine and β-alanine are important biological molecules and have zwitterion structure. In this study, L- alanine and β-alanine’s microscopic protonation...

Temperature dependence studies and microscopic protonation constants of L-alanine and β-alanine in acetonitrile – water mixtures

Published Online: Jul 28, 2022

Page range: 99 - 103

Received: Apr 07, 2022

Accepted: Jul 09, 2022

DOI: https://doi.org/10.2478/auoc-2022-0014

Keywords
L-alanine, β-alanine, microscopic protonation constants, thermodynamics parameters

© 2022 Hande Erensoy et al., published by Sciendo

This work is licensed under the Creative Commons Attribution-NonCommercial-NoDerivatives 3.0 License.

Temperature dependence studies and microscopic protonation constants of L-alanine and β-alanine in acetonitrile – water mixtures

Published Online: Jul 28, 2022

Page range: 99 - 103

Received: Apr 07, 2022

Accepted: Jul 09, 2022

DOI: https://doi.org/10.2478/auoc-2022-0014

KeywordsL-alanine, β-alanine, microscopic protonation constants, thermodynamics parameters

© 2022 Hande Erensoy et al., published by Sciendo

This work is licensed under the Creative Commons Attribution-NonCommercial-NoDerivatives 3.0 License.

Keywords
L-alanine, β-alanine, microscopic protonation constants, thermodynamics parameters