POLAROGRAPHIC REDUCTIVE BEHAVIOR OF ORGANIC SELENIUM AND SULFUR-COMPOUNDS CHARACTERIZED BY MERCURY ASSISTED CHEMICAL PRE-REACTIONS

In the polarographic reduction of organic selenium compounds the potential determining step is assigned to the reduction of mercury(I)-and/or mercury(II)-intermediates created in the surface layer of the electrode. Organic disulfides exhibit a more irregular reduction pattern and a limited number are readily reduced at the mercury electrode. Of main interest are thereby those revealing so-called Brdicka adsorption waves of reactant. Further aspects on the reduction mechanisms of sulfur compounds are obtained from S-oxides of diphenyl disulfides and methyl esters of aromatic sulfenic and sulfinic acids. Reduction cleavage of the sulfur-carbon bond has been followed in some structurally related alkyl aryl sulfides and sulfoxides. For ac polarography the anomalities can be explained by a linearized model for the faradaic current.