caa a22 4500 445328312 CHVBK 20180317142728.0 cr unu---uuuuu 170323e20110401xx s 000 0 eng 10.1007/s10953-011-9667-5 doi (NATIONALLICENCE)springer-10.1007/s10953-011-9667-5 Solute-Solvent Interaction Effects on Protonation Equilibrium of Some Water-Insoluble Flavonoids [Elektronische Daten] [Morteza Jabbari, Farrokh Gharib] The protonation constants of three different flavonoids (naringenin, chrysin, and daidzein) were determined in water-DMSO mixed solvents using a potentiometric method at 25.0 (±0.1) °C and 1.00mol⋅dm−3 tetra-n-butylammonium chloride as supporting electrolyte. The protonation constants were characterized and were analyzed in various solvent media in terms of the Kamlet, Abboud and Taft (KAT) parameters. Single-parameter correlations of the protonation constants versus α (hydrogen-bond donor acidity), β (hydrogen-bond acceptor basicity) or π ∗ (dipolarity/polarizability) are poor for all compounds, but the dual-parameter α and π ∗ correlation presents significant improvement with regard to the single- and multi-parameter models. A linear correlation is observed when the logarithm of the experimental protonation constants is plotted versus the calculated ones when the KAT parameters are considered. The protonation constants of the flavonoids in water were also calculated by the Yasuda-Shedlovsky extrapolation method at zero percent organic solvent. Finally, the results are discussed in terms of the effect of solvent composition on the protonation constants. Springer Science+Business Media, LLC, 2011 Protonation constant nationallicence Naringenin nationallicence Chrysin nationallicence Daidzein nationallicence Solvent effect nationallicence Water-DMSO solutions nationallicence Yasuda-Shedlovsky extrapolation nationallicence Jabbari Morteza Chemistry Department, Shahid Beheshti University, G. C., Tehran, Evin, Iran aut Gharib Farrokh Chemistry Department, Shahid Beheshti University, G. C., Tehran, Evin, Iran aut Journal of Solution Chemistry Springer US; http://www.springer-ny.com 40/4(2011-04-01), 561-574 0095-9782 40:4<561 2011 40 10953 https://doi.org/10.1007/s10953-011-9667-5 text/html Onlinezugriff via DOI 1 research-article jats NATIONALLICENCE 856 40 https://doi.org/10.1007/s10953-011-9667-5 text/html Onlinezugriff via DOI NATIONALLICENCE 700 1- Jabbari Morteza Chemistry Department, Shahid Beheshti University, G. C., Tehran, Evin, Iran aut NATIONALLICENCE 700 1- Gharib Farrokh Chemistry Department, Shahid Beheshti University, G. C., Tehran, Evin, Iran aut NATIONALLICENCE 773 0- Journal of Solution Chemistry Springer US; http://www.springer-ny.com 40/4(2011-04-01), 561-574 0095-9782 40:4<561 2011 40 10953 Metadata rights reserved Springer special CC-BY-NC licence nationallicence BK010053 XK010053 XK010000 NATIONALLICENCE NATIONALLICENCE NL-springer