Robust quantum chemical methods are employed to predict the pKas of several families of dual hydrogen-bonding
organocatalyts/anion receptors, including deltamides and croconamides as well as their thio-derivatives. The average accuracy of
these predictions is about 1 pH unit, and allow for a comparison of the acidity between classes of receptors and for quantitative
studies of substituent effects. These computational insights further explain the relationship between pKa and chloride anion affinity
of these receptors that will be important for designing future anion receptors and organocatalysts.