Why do acetal-forming reactions that use ethylene glycol have more favorable equilibrium constants than those using methanol?
A) Ethylene glycol reacts more rapidly.
B) They are more favorable on entropy grounds.
C) They are more favorable on enthalpy grounds.
D) Ethylene glycol is acidic and catalyzes the reaction.
E) The ethylene acetal can serve as a protecting group.

Question

Quizplus · Accepted Answer

Ethylene glycol has two hydroxyl groups, which can both react with the carbonyl group to form a cyclic acetal. This cyclic acetal is more stable than the acyclic acetal that would be formed from methanol, because the cyclic acetal has a lower ring strain. The lower ring strain makes the cyclic acetal more favorable on entropy grounds.

Why Do Acetal-Forming Reactions That Use Ethylene Glycol Have More