Atıf İçin Kopyala
Doʇan A., ASLAN N., Erden P. E., CANEL E., Klllç E.
Journal of Solution Chemistry, cilt.44, sa.8, ss.1705-1722, 2015 (SCI-Expanded)
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Yayın Türü:
Makale / Tam Makale
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Cilt numarası:
44
Sayı:
8
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Basım Tarihi:
2015
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Doi Numarası:
10.1007/s10953-015-0363-8
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Dergi Adı:
Journal of Solution Chemistry
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Derginin Tarandığı İndeksler:
Science Citation Index Expanded (SCI-EXPANDED), Scopus
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Sayfa Sayıları:
ss.1705-1722
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Anahtar Kelimeler:
Dimethyl sulfoxide-water mixture, Macroscopic/microscopic protonation constant, Solvent effect, α-Amino acid, α-Amino acid ester
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Ankara Hacı Bayram Veli Üniversitesi Adresli:
Evet
Özet
© 2015 Springer Science+Business Media New York.The acid-base chemistry of multidentate (bio)ligands are usually characterized in terms of macroscopic protonation constants, log10 K (or pK), which are composites of the microscopic constants (log10 k or pk) for the individual groups. In this study, macroscopic protonation constants of some α-amino acid (glycine, l-alanine, l-valine, l-leucine, l-phenylalanine, l-serine) and protonation constants of their methyl- and ethyl- esters in dimethyl sulfoxide-water mixtures (10-40 % dimethylsulfoxide by volume) were studied by potentiometric technique at 25.0 ± 0.1 °C under a nitrogen atmosphere, and at ionic strength of 0.10 mol·L-1 sodium chloride. The protonation constants were calculated by using the Best computer program and the constants were evaluated for microscopic protonation constants of these α-amino acids. The protonation constants are discussed on the basis of solute-solvent interactions. The constants were influenced by changes in solvent composition. The dipolar ionic form, however, still greatly predominates, even in 40 % dimethyl sulfoxide.