Absence Of Proton Donor Research Articles

Electrochemical Behavior of 2‐(1‐Naphrhyl)‐5‐Phenyl‐ and 2,5‐Diphenyloxazole

The electrochemical reduction of 2‐(l‐naphthyl)‐5‐phenyl‐ and 2,5‐diphenyloxazole in N,N‐dimethylformamide has been studied at platinum and mercury electrodes in the presence and absence of proton donors. Polarographic, potentiostatic, voltammetric, and spectrophotometric techniques were employed in the study. Both compounds are reduced via two polarographic steps. The first is a reversible one‐electron transfer producing a stable anion radical. The second is a reversible one‐electron transfer followed by rapid protonation of the dianion (EC process). The resulting protonated species undergoes a slow irreversible reaction. Addition of hydroquinone as a source of protons enhances the formation of the long term electrolysis product.

Polarography and Voltammetry in Dimethylsulfoxide

An exploratory voltammetric study of several acids, some representative metal ions, a few quinones, and oxygen has been made in the solvent dimethylsulfoxide (DMSO). Perchloric, sulfuric, and hydrochloric acids were found to be monoprotic strong acids in DMSO. Cobalt (II) and nickel (II) are reduced irreversibly at the dropping mercury electrode with large overpotentials indicating strong solvation. Polarograms of quinones showed two cathodic waves of unequal height in the absence of proton donor. The effect of proton donor on the polarograms of quinones was studied. The mechanism of the reduction of quinones in DMSO is discussed. Rotated platinum and rotated mercury pool electrodes can be used to advantage in DMSO.