Abstract
A pH potentiometric method is used to measure complex formation constants of aqueous alpha- and/or beta-cyclodextrin with several carboxylic acids and carboxylate anions: butyric acid/butyrate; valeric acid/valerate; hexanoic acid/hexanoate; octanoic acid/octanoate; decanoic acid/decanoate; cyclohexanecarboxylic acid/cyclohexanecarboxylate and benzoic acid/benzoate. Standard enthalpies and entropies of complex formation are calculated from the temperature dependencies of the equilibrium constants. These thermodynamic parameters of the alpha-cyclodextrin complexes largely conform to a correlation based on complexes with other substrate species previously reported. Both standard enthalpies and entropies of formation of beta-cyclodextrin complexes are found to be more positive than the corresponding complexes of alpha-cyclodextrin with the same substrates. These observations lead to insights into the bonding mechanism of cyclodextrin complexation.
Article PDF
Similar content being viewed by others
Avoid common mistakes on your manuscript.
References
M. L. Bender and M. Komiyama:Cyclodextrin Chemistry, Springer-Verlag, New York (1978).
D. D. NacNicol, J. J. McKendrick, and D. R. Wilson:Chem. Soc. Rev. 7, 83 (1978).
D. J. Wood, F. E. Hruska, and W. Saenger:J. Am. Chem. Soc. 99, 1735 (1977).
R. J. Bergeron, M. A. Charming, and K. A. McGovern:J. Am. Chem. Soc. 100, 2878 (1978).
E. A. Lewis and L. D. Hansen:J. Chem. Soc. 2, 2081 (1973).
K. Harata:Bull. Chem. Soc. Jpn. 51, 2737 (1978).
J. D. Behr and J. M. Lehn:J. Am. Chem. Soc. 98, 1743 (1976).
R. J. Bergeron and M. A. Charming:J. Am. Chem. Soc. 101, 2511 (1979).
T. Matsui, D. H. Evans, T. Osa, and N. Kabayashi:J. Am. Chem. Soc. 107, 3411 (1985).
R. I. Gelb, L. M. Schwartz, B. Cardelino, H. S. Fuhrman, R. F. Johnson, and D. A. Laufer:J. Am. Chem. Soc. 103, 1750 (1981).
T. Miyaji, Y. Kurono, and K. Uekama:Chem. Pharm. Bull. 24, 1155 (1976).
K. A. Connors and J. M. Lipari:J. Pharm. Sci. 65, 379 (1976).
R. I. Gelb, L. M. Schwartz, M. Radeos, R. B. Edmonds, and D. A. Laufer:J. Am. Chem. Soc. 104, 6283 (1982).
R. G. Bates:Determination of pH Theory and Practice, 2nd edn., Wiley: New York (1973), Ch. 3.
R. A. Robinson and R. H. Stokes:Electrolyte Solutions, 2nd revised edn., Butterworths, London (1965).
L. M. Schwartz:Anal. Chim. Acta 122, 291 (1980).
R. I. Gelb, L. M. Schwartz, R. F. Johnson, and D. A. Laufer;J. Am. Chem. Soc. 101, 1869 (1979).
Author information
Authors and Affiliations
Rights and permissions
About this article
Cite this article
Gelb, R.I., Schwartz, L.M. Complexation of carboxylic acids and anions by alpha and beta cyclodextrins. J Incl Phenom Macrocycl Chem 7, 465–476 (1989). https://doi.org/10.1007/BF01079783
Received:
Accepted:
Issue Date:
DOI: https://doi.org/10.1007/BF01079783