Colour effects with the Nitrobenzyll Esters of Dimethylaminobenzoic acids

Abstract

Nitrobenzyl esters of dimethylaminobenzoic acids are strongly coloured in the solid state but not in solution. The operation of electron donor-acceptor interaction within the crystal lattice is indicated. One of the compounds, o-nitrobenzyl m-dimethylaminobenzoate, formed two differently coloured polymorphic modifications.