Oxidation of a macrocyclic nickel(II) complex by alkyl hydroperoxides
- Iowa State Univ., Ames (United States)
Oxidation of NiL[sup 2+] (L = 1,4,8,11-tetraazacyclotetradecane) by alkyl hydroperoxides in acidic aqueous solutions produces NiL[sup 3+]. Kinetic measurements by the initial-rate method yielded rate constants that were ionic strength dependent. The yields of NiL[sup 3+] depend on the relative concentrations of the reactants and improve in the presence of oxygen. Possible causes for these observations are discussed. Bromide ions alter the stoichiometry and products of the reaction with tert-butyl hydroperoxide but have no effect on the reaction with tert-amyl hydroperoxide. This difference is rationalized in terms of the relative reactivities of the intermediate alkoxyl radicals toward [beta]-scission versus bromide oxidation. The addition of alcohols containing [alpha]-hydrogens (CH[sub 3]OH and (CH[sub 3])[sub 2]CHOH) decreases substantially the yield of NiL[sup 3+] for reactions with both hydroperoxides. Evidence is presented to attribute this effect to the reduction of NiL[sup 3+] by the [alpha]-hydroxyalkyl radicals formed in the reactions of alcohols with alkyl and alkoxyl radical intermediates. 30 refs., 2 figs., 1 tab.
- DOE Contract Number:
- W-7405-ENG-82
- OSTI ID:
- 6322979
- Journal Information:
- Inorganic Chemistry; (United States), Journal Name: Inorganic Chemistry; (United States) Vol. 32:8; ISSN 0020-1669; ISSN INOCAJ
- Country of Publication:
- United States
- Language:
- English
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Related Subjects
400201* -- Chemical & Physicochemical Properties
ALCOHOLS
AQUEOUS SOLUTIONS
CHARGED PARTICLES
CHEMICAL REACTION KINETICS
CHEMICAL REACTIONS
COMPLEXES
DISPERSIONS
ELEMENTS
HYDROXY COMPOUNDS
IONS
KINETICS
MIXTURES
NICKEL COMPLEXES
NONMETALS
ORGANIC COMPOUNDS
OXIDATION
OXYGEN
OXYGEN COMPOUNDS
PEROXIDES
RADICALS
REACTION INTERMEDIATES
REACTION KINETICS
REDUCTION
SOLUTIONS
STOICHIOMETRY
TRANSITION ELEMENT COMPLEXES