THE STRUCTURE OF 2-<i>p</i>-DIMETHYLAMINOBENZYLIDENEINDOXYL AND ITS SALTS

Abstract

2-p-Dimethylaminobenzylideneindoxyl has been shown to have mainly the dipolar quinonoid structure (II), though quaternization takes place at the dimethylamino nitrogen atom in the unperturbed structure (I). This has been established by a study of its infrared and ultraviolet absorption spectra and by a comparison of these with those of its monohydrochloride, its methiodide, and of 2-benzylideneindoxyl.