Dynamic effects of solvent on the Brönsted α

In hydroxylic solvents the primary kinetic isotope effect on reactions which transfer hydride between NAD+ analogues is maximized and constant, and the Brönsted α indicates a critical configuration equally resembling reactants and products. However, in certain polar, aprotic solvents, most notably DMSO, the isotope effect is sharply reduced and the Brönsted a indicates a product-like critical configuration. These changes are attributed to a barrier due to solvent