Spectroelectrochemical Studies on the Reduction of Thionyl Chloride

The electrochemical reduction of thionyl chloride in dimethyl sulfoxide and of the thionyl chloride‐lithium tetrachloroaluminate system has been studied using spectroelectrochemical techniques. Results indicate that the reduction mechanism of in the solution is essentially the same as that in DMSO. The key intermediate species in this reduction is shown to be , which is produced upon reduction of by a one‐electron transfer, followed by the dechloridation process. This species then undergoes a series of following reactions to produce the final reduction products, S and , via other intermediates such as and . At very negative potentials, reduction products of S and are shown to be produced.