Reaction with acetic anhydride as a method for estimating the basicity of exocyclic amino groups in nitrogen heterocycles

Abstract

Relative rates for acetylation of various anilines and amino heterocycles with acetic anhydride in pyridine were determined by a competition method. From a Bronsted plot of reactivity against basicity for the anilines, and by considering the heterocycles as substituted anilines, pK_a values for the amino group in a variety of heterocycles have been obtained.