I. Gomezorellana et al., MICROCALORIMETRIC TITRATION OF ALPHA-CYCLODEXTRIN WITH SOME STRAIGHT-CHAIN ALPHA,OMEGA-DICARBOXYLATES IN AQUEOUS-SOLUTION AT DIFFERENT TEMPERATURES, Journal of the Chemical Society. Faraday transactions, 90(22), 1994, pp. 3397-3400
Citations number
33
Categorie Soggetti
Chemistry Physical","Physics, Atomic, Molecular & Chemical
The complex formation of alpha-cyclodextrin and straight-chain aliphat
ic alpha,omega-dicarboxylates, -O2C(CH2)nCO2-(n = 6, 7, 8), in aqueous
solution has been studied by titration microcalorimetry at 288.15, 29
8.15 and 308.15 K. Apparent Gibbs energies, enthalpies, entropies and
heat capacities for the 1 : 1 complex formations were derived from the
calorimetric data. The thermodynamics of binding show typical enthalp
y-entropy compensation effects, which result in weak temperature depen
dences of the Gibbs energies. The heat capacities of binding are large
and negative. This confirms the view that the binding of non-polar mo
ieties to cyclodextrins is to a large extent a result of hydrophobic d
ehydration. Experimental conditions causing deviations from the 1 : 1
model, are also discussed.