Schiff base equilibria. I. Formation and distribution of N-n-butylsalicylideneimine

Abstract

The equilibrium constant governing the formation of a Schiff base from salicylaldehyde and n-butylamine in aqueous solution has been evaluated by spectrophotometry as 5.62 x 10⁴. The pK of the phenolic group of the Schiff base is 12.0. These constants have been used to account for the distribution of salicylaldehyde between water and toluene in the presence of butylamine. The neutral form of the Schiff base has a distribution coefficient of 1.9 x 10³.