Properties of α-Ferrocenylcarbenium and Ferricinium Salts by Nonaqueous Potentiometric Titration

Potentiometric titration of -ferrocenylcarbenium and ferricinium salts in anhydrous acetonitrile with sodium ethylate involves redox reaction between the titrate and titrant, which, once equimolar amount of the latter has been added, produces a potential jump of 300-400 mV (platinum indicator electrode). The oxida- tion potentials of the -ferrocenylcarbenium and ferricinium salts in anhydrous acetonitrile were estimated at 410-500 mV. The experimental data gave evidence for intramolecular redox processes (redox tautomerism) in the compounds studied.