Potentiometric titrations of some mono methyl substituted and 5-keto mono methyl substituted hexadecanoic acids in nonaqueous media

Abstract

The potentiometric titrations of 5-keto-7, 9-monomethyl substituted-hexadecanoic acids and 3, 9-monomethyl-substituted-hexadecanoic acids have been made by using tetrabuthylammonium hydroxide (TBAH) in 2-propanol as titrant. The potentiometric titration curves of the compounds have been drawn, and their Pk(a) values calculated. The acidity of these compounds have been interpreted in terms of the relative positions of substituents. It has been observed that keto group increases and methyl group decreases the acidity of substituted hexadecanoic acids.