Descriptors for the α,ω-dicarboxylic acids from oxalic acid to sebacic acid

Abstract

We use literature data on solubilities in water and solvents, water-solvent partition coefficients and vapor pressures at 298 K to obtain Abraham (Absolv) descriptors for the neutral, unionized, forms of oxalic acid, malonic acid, glutaric acid, succinic acid, pimelic acid, suberic acid, azaleic acid and sebacic acid. With a knowledge of equations for partition coefficients for numerous water-wet solvents, water to dry solvents and water to ionic liquid systems, we can then predict partition coefficients of the various acids in a huge number of systems. We set out the solubility of the acids in water and these, together with estimated partition coefficients yield solubilities of the acids into the corresponding solvents. The descriptors themselves show that the acids are dipolar, are strong hydrogen bond acids and reasonably strong hydrogen bond bases, although their hydrogen bond acidity is less than expected for compounds containing two (independent) carboxylic acid groups.