Are the pKa values of free fatty acids in aqueous solution abnormally high? An NMR and computational perspective

Abstract

Accurate dissociation constants of the carboxylic groups of free fatty acids in aqueous solution are unknown, and a wide range of values extending over 5 pK_a units have been suggested. We reinvestigated the problem with the use of ¹H and ¹³C NMR and DFT methods and demonstrate that the pK_a values fall within those of typical organic acids.