The Aldol Condensation of Acetaldehyde: the Equilibrium Constant for the Reaction and the Rate Constant for the Hydroxide Catalyzed RetroAldol Reaction

Abstract

An indirect thermochemical estimate of the equilibrium constant for the aldol condensation of acetaldehyde suggested that this reaction was much less irreversible than has been believed. The rate of the hydroxide catalyzed retroaldol reaction has been measured; k21 = 2.8 × 10−3 M−1 s−1 at 25°, so that the equilibrium constant is 4.0 × 102 M−1. The γ value for acetaldehyde as addend is 0.40. The enthalpy change for the aldol reaction is −9.84 kcal/mol.