Mixed dimers of chloroacetic acids and decanoic acid in benzene

Abstract

The formation of mixed dimers of acetic, monochloroacetic, dichloroacetic and trichloroacetic acids with decanoic acid has been studied by partition and solubility measurements of water in benzene. The dimerization constants of these acids decrease with increasing acidity of the acids, while the reverse is found for the hydration constant of the acid monomer monohydrate. The formation constants of the mixed dimers have been determined for the following acid pairs: acetic–decanoic, monochloroacetic–decanoic, dichloroacetic-decanoic and trichloroacetic–decanoic. The formation constant is just as expected statistically for all these acid pairs. Linear free energy relationships have been observed between the formation of dimeric acids and acid monomer monohydrates and the dissociation of acids in water.