Über die Reaktivität des Schwefeldioxid-Radikalanions gegenüber reduzierbaren Substraten

A survey of reactions of the electrolytically prepared sulfurdioxide anion radical with various substrates containing reducible groups under aprotic and slightly protic conditions is presented. Beyond known reactions with mono-, vicinal and 1,-dihalides only -halogencarbonyl-, polyhalide-, nitro- and nitrosocompounds are reducible by this reagent. Aldehydes and carboxylic acid halides react but retain their state of oxidation. Anhydrides, esters and ketones are almost inert. Mechanisms are discussed and the scope for the use of S₂O ₄ ^– as a nucleophile for the synthesis of sulfones and as a reducing agent is defined.