Abstract: The enthalpies and free energies of the acid-catalyzed hydrolysis of a series of alkyl-substituted dimethyl ketals have been determined in a model study of steric effects. The measured enthalpy differences did not correlate with standard quantitative notions of the steric bulk of the substituents, although the overall free-energy changes fit the expected order. The entropy effect of the substituents is a dominant factor in determining the ...
