Study of reactions of obtaining anion-radical of oxygen: one-electron oxygen reduction and complex formation in the system of crown-ether - potassium superoxide - solvent. Investigation of the possibility of regulating the activity of two different supramolecular structures containing oxygen anion radical to create new antioxidant systems. The oxygen anion radical in solution was obtained by the method of electrochemical oxygen reduction, as well as by complexation in the system of crown ether – potassium superoxide – solvent. The amount of oxygen radical anion obtained was monitored spectrophotometrically using a high-quality reaction with tetrazolium blue and the potentiometric method using an exchange reaction with butyl bromide. The activity of two different supramolecular structures containing oxygen anion radical is compared. It is shown that in the transition from the chemical method of generation of oxygen anion radical to electrochemical, the activity of the anion radical in the reaction with alkyl halide increases slightly. Spectrophotometrically and potentiometrically determined the kinetic parameters of the electrochemical oxygen reduction in the aprotic medium, as well as the process of complexation in the system of crown ether – potassium superoxide – solvent. The activity of two different supramolecular structures containing anion-radical of oxygen with the (Crown-K)+ and (tetraethylammonium)+ ions in reaction with propyl bromide in acetonitrile was compared. The conducted studies allow us to choose the optimal mode and structure of the complex - the sources of oxygen anion radical, depending on the task and goals of the experiment. The study of the complexation reaction in the system of crown ethers - potassium superoxide - solvent, along with the electrochemical method of obtaining active oxygen, is necessary not only in terms of obtaining the most stable form of oxygen anion radical, but also the creation of model systems that allow to analyze the mechanisms and patterns of the processes in biological systems. The obtained results indicate the prospect of using the investigated supramolecular complexes containing oxygen anion radical to create new antioxidant systems that can be used as new classes of antioxidants for engineering, medicine and pharmacy purposes.
Ultrasound promoted N-alkylation of pyrrole using potassium superoxide as base in crown ether