Electrochemical behaviour of 5-methyl-(2-thiazolylazo)-resorcinol

The electrochemical reduction of 5-Methyl-(2-Thiazolylazo)- Resorcinol (5-Me-TAR) was studied in %30 ethanol/water mixture having various pH values using square wave voltammetry (SWV), differential pulse polarography (DPP), sampled d.c. polarography (SCP) and cyclic voltammetry (CV). Three straight lines were obtained from the E p -pH plots for the compound. The pK a values of the dye were obtained as 6.50 and 10.99. The reduction behaviour of 5-MeTAR is explained in acidic, neutral and alkaline media and a reaction mechanism has been suggested.