Hydrogen Bonding in Organic Compounds. VIII. Aromatic Primary Amines with ortho-Carbonyl Groups

Abstract

The NH stretching frequencies of the amine group in a number of aromatic primary amines with o-carbonyl groups have been studied as the fundamental and first overtone absorption bands, both before and after deuteration. Several correlations are established between functions of the vibration frequencies which seem to be related to the strengths of the hydrogen bonds that have been formed. These correlations, established for carbonyl as the acceptor, extend to some other classes of hydrogen bond acceptor. When bilateral hydrogen bonds are formed to two o-carbonyl groups the NH₂ stretching frequencies do not conform to the equation of Bellamy and Williams. Further evidence in favour of the interpretation of the spectrum of 1-aminoanthraquinone given by Hambly and Bonnyman is offered. The preparation of 5-chloro-2-t-butylaniline is described and some further details of the spectra of anilines with tertiary butyl substituents are given.