Solvent Effect on the Isomeric Equilibrium of Carbohydrates: The Superior Ability of 2,2,2-Trifluoroethanol for Intramolecular Hydrogen Bond Stabilization

The higher aptitude of 2,2,2-trifluoroethanol for intramolecular hydrogen bond stabilization in carbohydrates is suggested. This belief, arising from the analysis by 1H NMR spectroscopy of the solvent effect of D2O, DMSO-d6, and 2,2,2-trifluoroethanol-d3 on the isomeric equilibrium of caryophyllose, was also confirmed by shifting of the conformational equilibria of â-ribopyranose and of its methyl glycoside.