Nitrosyl complexes cobalt, reaction with oxygen

PtG. 20. The proposed mechanism for the reaction of 5-coordinate cobalt nitrosyl complexes with oxygen. 

Clarkson SG, Basolo F (1973) Study of reaction of some cobalt nitrosyl complexes with oxygen. Inorg Chem 12 1528-1534... 

LCon02] + RH2— [LCo i02H]- + RH followed by reactions of the radicals and HOa. In the case of the suporoxocobalamin complex, the [LCo OaH] complex has been characterized spectroscopically. In the reactions of nitrosyl-Schiflf-base-cob dt(n) [L Co(NO)] complexes with oxygen in the presence of base, B (e.g. pyridine), the formation of nitro-complexes has been reported. Kinetic studies show the reaction to be first order in [Oa] and cobalt complex. Quantitative uptake of 0.5 mole of dioxygen per mole of complex observed is in accord with the scheme... 

Oxygen-transfer reactions have been shown to occur from cobalt(III)-nitro complexes to alkenes coordinated to palladium.472 Thus ethylene and propene have been oxidized stoichiometrically in quantitative yields to acetaldehyde and acetone respectively, with the concomitant reduction of the nitro- to the nitrosyl-cobalt analog. A catalytic transformation with turnover numbers of 4-12 can be achieved at 70 °C in diglyme. The mechanism shown in Scheme 11 has been suggested. 

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