Thermodynamics of hyrolysis of aliphatic ketals. An entropy component of steric effects

Journal Article · Wed Sep 12 00:00:00 EDT 1979 · J. Am. Chem. Soc.; (United States)

DOI:https://doi.org/10.1021/ja00513a009· OSTI ID:5832082

Wiberg, K B; Squires, R R

The enthalpies and free energies of the acid-catalyzed hydrolysis of a series of a 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 quilibrium composition for this reaction. Possible origins for these entropy effects are discussed. (5 tables)

• Research Organization: Yale Univ., New Haven, CT
• OSTI ID: 5832082
• Journal Information: J. Am. Chem. Soc.; (United States), Journal Name: J. Am. Chem. Soc.; (United States) Journal Issue: 19 Vol. 101:19; ISSN JACSA
• Country of Publication: United States
• Language: English

Related Subjects

37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CHEMISTRY
400301* -- Organic Chemistry-- Chemical & Physicochemical Properties-- (-1987)
ACETALS
CHEMICAL REACTIONS
DECOMPOSITION
ENERGY
ENTHALPY
ENTROPY
ETHERS
FREE ENERGY
HYDROLYSIS
LYSIS
ORGANIC COMPOUNDS
ORGANIC OXYGEN COMPOUNDS
PHYSICAL PROPERTIES
SOLVOLYSIS
THERMODYNAMIC PROPERTIES
THERMODYNAMICS