Effect of the electrode material on the electrochemical reduction of some 2,5-dihydro-1,3,4-thiadiazoles

During cyclic voltammetric studies of the 2,5-dihydro-1,3,4-thiadiazoles (Δ 3 -1,3,4-thiadiazolines) (1a-e) on HMDE in 0.1 x 10 - 3 mol/dm 3 LiClO 4 acetonitrile and aqueousacetonitrile or aqueous-ethanol Britton-Robinson's buffer solutions in second polarization cycle, besides peaks equivalent to polarographic waves, an additional new system of peaks was observed. The corresponding analogous system of additional peaks has not been observed during the reduction of these substances on electrodes of other materials, as i.e., platinum, gold or glassy carbon. This study showed that it results from the oxidation and reduction of organo-mercury compounds, formed in reaction of the electrode material (Hg) with an adsorbed product of2,5-dihydro-1,3,4-thiadiazoles reduction.