Volume changes on mixing the enantiomers of N-trifluoroacetylamino acid methyl esters (N-TFA-amino acid-OMe) were determined at 25 degrees C by means of a high-precision vibrating-tube densimeter. The excess molar volumes (V-E) for the racemic mixtures of N-TFA-Ala-OMe 1, N-TFA-Val-OMe 2, and N-TFA-Leu-OMe 3, were found as V-E = 0.0098, -0.0458, and 0.035 cm(3) mol(-1), respectively. For 2 and 3, these volumetric effects of discriminating interactions between enantiomers in the liquid phase are the largest ever observed.