Welcome to LookChem.com Sign In|Join Free

Article Doi

Kinetic Studies of the Reduction of Nickel Oxime Complexes by Tris(1,10-phenanthroline)cobalt(II) and Hydroquinone in Aqueous Media

DOI: 10.1039/DT9880002279

Source and publish data:

Journal of the Chemical Society, Dalton Transactions p. 2279 - 2286 (1988)

Update date:2022-08-30

Topics:

Authors:

McAuley, AlexanderMcAuley, Alexander

Macdonald, Christopher J.Macdonald, Christopher J.

Spencer, LeeSpencer, Lee

West, Paul R.West, Paul R.

Read Full Text PDF DownLoad Join now for total 90,000,000 free articles

Article abstract of DOI:10.1039/DT9880002279

Rate studies have been made on the reduction of a nickel(IV) bis-oxime, bis(6-amino-3-methyl-4-azahex-3-en-2-one oximato)nickel(IV), 3)2>2+, and a nickel(III) mono-oxime (15-amino-3-methyl-4,7,10,13-tetra-azapentadec-3-en-2-one oximato)nickel(III), 1)>2+, species using 2+ (phen=1,10-phenanthroline) and hydroquinone (H2quin), and on the oxidation of II(HL1)>2+ using III(L4)2>3+ (L4=1,4,7-triazacyclononane).Reactions were carried out in the pH range 4-8, and using the lack of proton dependence on the rate associated with CoII reductions, it is possible to distinguish pathways involving species derived from proton-related equilibria for both the nickel complexes and hydroquinone.Self-exchange rates have been determined using a Marcus correlation.In the case of the monoxime, for the deprotonated couple, III(L1)>2+-II(L1)>+, kexc.=(4+/-2) x 102 dm3 mol-1 s-1 and for III(HL1)>3+-II(HL1)>2+, kexc. ca.6 x 102 dm3 mol-1 s-1.For the deprotonated bis-oxime complexes IV(L3)2>2+-III(L3)2>+ and III(L3)2>+-II(L3)2>0, kexc.=(8+/-3) x 104 and (8+/-4) x 103 dm3 mol-1 s-1 respectively.For the protonated couple, (pK=4.43+/-0.04), III(L3)(HL3)>2+-II(L3)(HL3)>+, kexc. ca.5 x 102 dm3 mol-1 s-1.However, for the reactions of the nickel(III) species with the quinone and catecholate anions, Hquin- and Hcat-, there is evidence for an inner-sphere process which may be substitution controlled.The rate constants are compared with the few data previously available, and are discussed with regard to the inner-sphere reorganisation required for electron transfer.

View More

Products guided by the article

Product name:1,4-Benzoquinone

Cas No:106-51-4

106-51-4

R&D Labs maybe for 106-51-4

Relevant to this article

Hot Product