ISSN:
1572-8927
Keywords:
α-D-glucose
;
β-D-fructose
;
sucrose
;
enthalpies of solution
;
mutarotation
;
preferential solvation
;
hydrophobic hydration
Source:
Springer Online Journal Archives 1860-2000
Topics:
Chemistry and Pharmacology
Notes:
Abstract Enthalpies of solution of β-D-fructose and sucrose in binary solvent mixtures of water and N,N-dimethylformamide (DMF) at 25°C over the whole mole fraction region are reported and compared to those of α-D-glucose. Because in these solvent systems the mutarotation of β-D-fructose is fast and accompanied by large enthalpy changes, the measured enthalpies of solution of this compound had to be corrected for this effect. The dependences of the enthalpies of solution on the composition of the solvent mixtures are considered to result from preferential hydrogen-bonding of the hydroxyl groups and hydrophobic hydration of the apolar parts of the surface of the solute molecule. Distinctions between the enthalpy of transfer curves are discussed in terms of conformational differences and additivity aspects in the solvation behavior of the compounds. The predominance of furanose forms of fructose in DMF and that of pyranose forms of the same solute in water are related to differences in solvation.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1007/BF00646433
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