Studies on Dithiocarbamates: Part VI. Polar Substituent Effect on the Absorption Spectra of Azorhodanines

A series of azo-rhodanines (II) were prepared from 3-benzylrhodanine and diazotised substituted ani­lines. Examination of spectral data (visible) in terms of substituent effect on ʎmax (π→π* transition) shows a good linear relationship (Hammett's σp relation). The corresponding UV data suggest baneful effect of azo-chromophore at C5 on the delocalisation of S-electrons, Evidences presented here indicate trans-orienta­tion of II around -N=N- bond.