Abstract
<jats:p>In this study, a flowchart for an environmentally friendly and energy-saving technology for converting toxic cy-cloalkane and arenethiols into symmetrical disulfides with biological activity was developed. The proposed technology combines two sequential steps: the extraction of thiols from hydrocarbon fuels and the electrosynthesis of useful disulfides in an organic medium. An ionic liquid serves as an extractant for the studied alicyclic and aromatic thiols (cyclopentanethiol, cyclohexanethiol, and thiophenol), which then serves as a dual solvent and supporting electrolyte in the next step of the process. This study examines ionic liquids (1-butyl-3-methylimidazolium tetrafluoroborate, 1-butyl-3-methylimidazolium methyl sulfate, 1-ethyl-3-methylimidazolium ethyl sulfate, and 1-butyl-3-methylimidazolium hexafluorophosphate), which are highly specific extractants for thiols. Electrosynthesis is achieved by applying an electric current to a mixture of ionic liquids of various structures with acetonitrile at room temperature and atmospheric pressure. Indirect oxidation of thiols, potential components of liquid fuel, occurs in the presence of an electrochemically activated form of tetra-n-butylammonium bromide. The use of salt as a mediator increases the efficiency of electrosynthesis and reduces energy consumption compared to the direct electrooxidation of thiols to disulfides. The proposed mediator – a redox pair of bromine anion/bromine radical – has a high degree of regeneration, enabling its repeated use in a cyclic process. Replacing traditional media with conductive ionic liquids, which simultaneously serve as a solvent and supporting electrolyte, allows for simplified isolation of the target electrosynthesis products. Thiophenol proved to be the most effective of the thiols examined, yielding a disulfide with a yield of 47.3%. The biological activity of the resulting disulfides of various structures was assessed using the PASS computer prediction method.</jats:p>