Transition-state structure for the hydronium-ion-promoted hydrolysis of α- d-glucopyranosyl fluoride.

The transition state for the hydronium-ion-promoted hydrolysis of α- d-glucopyranosyl fluoride in water has been characterized by combining multiple kinetic isotope effect measurements with theoretical modelling. The measured kinetic isotope effects for the C1-deuterium, C2-deuterium, C5-deuterium, anomeric carbon-13, and ring oxygen-18 are 1.219 ± 0.021, 1.099 ± 0.024, 0.976 ± 0.014, 1.014 ± 0.005, and 0.991 ± 0.013, respectively. The transition state for the hydronium ion reaction is late with respect to both C-F bond cleavage and proton transfer. [ABSTRACT FROM AUTHOR]