A vanadium-based chemical oscillator: Identification of chemical species responsible for the redox reaction and construction of a simplified model

To identify the chemical species involved in a unique, vanadium-based chemical oscillator reaction, products derived from indole in the oscillation solution were isolated and characterized. NMR and mass spectra showed that 3,3-dichloro-2-oxoindole and isatin were formed during the oscillation process. The formation of these two compounds suggests that peroxo species such as CHCl₂OO^· and CHCl₂OOH play a key role in the construction of the oscillation system. A skeletal model for the system is proposed based on these findings.