[Acid-base equilibrium of hydrazone derivatives 4-R-3R1-thazol-2-one. I. Ionization constants of alpha-methyl-beta-(4-R-thiazol-2-yl)- and alpha-methyl-beta-(4-R-3-R1-thiazol-2-ylidene)-hydrazides of benzoic acid].
The ionization constants of the following compounds have been determined spectrophotometrically in aqueous solution: [table: see text] The comparison of absorption spectra in UV and pK values of the compounds being described in this work and of the derivatives having a thiazole or thiazoline structure which were studied previously let us suggest that in the II-H neutral molecule and the I-H and II-H mono-anion the thiazole form prevails while in the case of the I-H neutral molecule the thiazoline form is more probable.
Katedra i Zakład Chemii Ogólnej, Akademia Medyczna w Lublinie.
L
L
Bielak
M
M
Kiełczykowska
S
S
Biliński
D000136:Acid-Base Equilibrium; D001565:Benzoates / Q000737:chemistry*; D006835:Hydrazones / Q000737:chemistry*; D009994:Osmolar Concentration; D013053:Spectrophotometry; D013844:Thiazoles / Q000737:chemistry
D001565:Benzoates; D006835:Hydrazones; D013844:Thiazoles
Równowaga kwasowo-zasadowa pochodynch hydrazonu 4-R-3-R1-tiazol-2-onu. I. Stałe jonizacji alpha-metylo-beta-(4-R-tiazol-2-ilo)-oraz alpha-metylo-beta-(4-R-3-R1-tiazol-2-ilideno)-hydrazydów kwasu benzoesowego.