MOLECULAR RECOGNITION AND EFFECTS OF STERIC AND GEOMETRIC ISOMERISM -THERMODYNAMIC STUDY OF NONBONDING INTERACTIONS IN AQUEOUS-SOLUTIONS OF CYCLOALKANOLS

Enthalpies of dilution of binary and ternary aqueous solutions contain ing cyclobutanol, cyclopentanol, cyclohexanol, cycloheptanol, cyclooct anol, (1R,2R)-trans-cyclohexane-1,2-diol, (1S,2S)-trans-cyclohexane-1, 2-diol, (1R,2S)-cis-cyclohexane-1,2-diol, (1R,2R)-trans-cyclopentane-1 ,2-diol, (1S,2S)-trans-cyclopentane-1,2-diol, (1R,2S)-cis-pentane-1,2- diol, cis-cyclooctane-1,2-diol, cis-cyclooctane-1,4-diol, cis-cyclooct ane-1,5-diol, cis,cis-cyclohexane-1,3,5-triol and myo-inositol were de termined by microcalorimetry at 298.15 K. Pairwise self- and cross-int eraction coefficients of the virial expansion of the excess enthalpies were evaluated. The values of these coefficients are positive, depend ing in a very complex manner on the number of the hydroxy groups on th e cyclic molecule and on steric and geometric isomerism. They have bee n interpreted according to an interaction model which indicates a pref erential configuration between two hydrated interacting molecules, sta bilized by the simultaneous juxtaposition of groups having the same ac tion on water structure.