Electrochemical Activation of Sulfur in Organic Solvents-New Syntheses of Thioorganic Compounds with a Sacrificial Carbon-Sulfur Electrode

Abstract

Abstract This review details new methods of preparation for thioorganic compounds derived from the electrogenerated species Sx 2- and Sy 2+. Since sulfur has poor solubility in the organic solvents used in electrochemisty it is introduced in the mass of the electrode together with powdered graphite to assure good electric conductivity. When it is used as a cathode at a working potential of about −0.9 V (vs. SCE), the nucleophilic species Sx 2- is generated. With a working potential of 2.0 V it is possible to electrogenerate the electrophilic species Sy 2+. Through reactions with various substrates we could prepare thiophenes, sulfur-containing heterocycles, sulfides, trisulfides, etc. A vicarious nucleophilic substitution has also been observed. High selectivity and regioselectivity are observed in reactions with Sy 2+