Analysis of the Induction Period and Proposal of Mechanism for the Catalysis of 3-Methylindole Oxygenation by Two Isomers of N, N'-(1, 2-Cyclohexylene) bis (3-tert-butylsalicylideneaminato) cobalt (II)

抄録

The factors which govern the induction period in the catalysis of 3-methylindole oxygenation by the title complexes were investigated. Electron spin resonance measurements showed that the superoxo-cobalt complex observed in the induction period disappeared at the start of the steadystate consumption and that the superoxo complex was preferentially converted to a cobalt (II)-substrate complex. During the induction period, the cobalt (II) complexes are converted to cobalt (III) species via their dioxygen adducts in the presence of dioxygen and the substrate, 3-methylindole. For the steady state, a mechanism is proposed which involves a cobalt (III)-anion complex as the catalytic species; facile oxygen introduction takes place at the coordinated deprotonated substrate.