Reactions of copper(I) in perchlorate solution. Kinetics and mechanisms of the reduction of cobalt(III) complexes by copper(I)

Parker, O. J.; Espenson, James H.

doi:10.1021/ja01036a018

Cited by 33 publications

(21 citation statements)

References 10 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…39 We are not aware of any comparable analysis of the relative conductivities of chloride and cyanide as bridging ligands but note that in the inner-sphere reduction of Co  (NH 3 ) 5 X 2ϩ by Cu ϩ aq, the rate for X = Cl Ϫ exceeds that for X = CN Ϫ by seven orders of magnitude. 40 also the ligand which is transferred. The third mechanism is penetration of the aryl radical into the primary coordination shell of the metal, formally to give L-Cu  -Ar, which then undergoes reductive elimination to Ar-L and Cu  .…”

Section: (Ii) the Mechanism Of The Ligand Transfer Stepmentioning

confidence: 99%

Sandmeyer reactions. Part 6.1 A mechanistic investigation into the reduction and ligand transfer steps of Sandmeyer cyanation

Hanson

Rowell

Taylor

et al. 2002

J. Chem. Soc., Perkin Trans. 2

View full text Add to dashboard Cite

For Sandmeyer cyanation at 298 K in 50% v/v aqueous acetonitrile buffered at pH 8, absolute rate constants have been obtained for the reduction of 4-methoxybenzenediazonium tetrafluoroborate by the cyanocuprate() anions Cu  (CN) 4 3Ϫ , Cu  (NCMe)(CN) 3 2Ϫ and Cu  (NCMe) 2 (CN) 2 Ϫ as (0.50 ± 0.05), (0.12 ± 0.03) and 0.0 dm 3 mol Ϫ1 s Ϫ1 , respectively. The relative reactivity of the two reactive cyanocuprates reflects the estimated difference in their standard reduction potentials. Ligand transfer to the aryl radical from the cyanocuprate() anions produced in the reaction occurs within the solvent cage. By use of radical clocks, first order rate constants of the order of 1 × 10 8 s Ϫ1 for ligand transfer between the caged reactants can be evaluated although the transfer rate may vary from one aryl radical to another. No difference was discerned in ligand transferring reactivity between the two cyanocuprate() complexes involved.

show abstract

Section: (Ii) the Mechanism Of The Ligand Transfer Stepmentioning

confidence: 99%

Sandmeyer reactions. Part 6.1 A mechanistic investigation into the reduction and ligand transfer steps of Sandmeyer cyanation

Hanson

Rowell

Taylor

et al. 2002

J. Chem. Soc., Perkin Trans. 2

View full text Add to dashboard Cite

show abstract

“…The first term in the denominator of equation ( 4) has been obtained by substitution using the relationship in equation (8). Simple rearrangement of equation ( 4) yields (9).…”

Section: Direct Monitoring Of Copper(ii) Disappearancementioning

confidence: 99%

Kinetic study of the oxidation of ascorbic acid by aqueous copper(II) catalysed by chloride ion *

Sisley¹,

Jordan²

1997

J. Chem. Soc., Dalton Trans.

View full text Add to dashboard Cite

“…This ratio should be large in the event of a non-bridging ligand effect [23][24][25]. However, the small ratio obtained in this work could be explained by the greater coulumbic force of attraction between the negatively charged [Co(CN) 5 NO 2 ] 3) and TiOH 2+ than the repulsion between the positively charged species [Co(NH 3 ) 5 NO 2 ] 2+ and TiOH 2+ , which therefore tends to close the reactivity gap.…”

Section: Resultsmentioning

confidence: 65%

Outer-Sphere electron-transfer and the effect of linkage isomerism in the titanium(III) reduction of nitro-pentacyanocobaltate(III) and nitro-, and nitrito-pentaamminecobalt(III) complexes in aqueous acidic media

Ojo

Ogunlusi

Adegoke

2007

Transition Met Chem

View full text Add to dashboard Cite

The reductions of [Co(CN) 5 NO 2 ] 3) , [Co(NH 3 ) 5 NO 2 ] 2+ and [Co(NH 3 ) 5 ONO] 2+ , by Ti III in aqueous acidic solution have been studied spectrophotometrically. Kinetic studies were carried out using conventional techniques at an ionic strength of 1.0 mol dm )3 (LiCl/HCl) at 25.0 ± 0.1°C and acid concentrations between 0.015 and 0.100 mol dm )3 . The second-order rate constant is inverse-acid dependent and is described by the limiting rate law:-where k=k¢K a and K a is the hydrolytic equilibrium constant for [Ti(H 2 O) 6 ] 3+ . Values of k 0 obtained for [Co(CN) 5 NO 2 ] 3) , [Co(NH 3 ) 5 NO 2 ] 2+ and [Co(NH 3 ) 5 ONO] 2+ are (1.31 ± 0.05) Â 10 )2 dm 3 mol )1 s )1 , (4.53 ± 0.08) Â 10 )2 dm 3 mol )1 s )1 and (1.7 ± 0.08) Â 10 )2 dm 3 mol )1 s )1 respectively, while the corresponding k¢ values from reductions by TiOH 2+ are 10.27 ± 0.45 dm 3 mol )1 s )1 , 14.99 ± 0.70 dm 3 mol )1 s )1 and 17.93 ± 0.78 dm 3 mol )1 s )1 respectively. Values of K a obtained for the three complexes lie in the range (1-2) Â 10 )3 mol dm )3 which suggest an outer-sphere mechanism.

show abstract

Reactions of copper(I) in perchlorate solution. Kinetics and mechanisms of the reduction of cobalt(III) complexes by copper(I)

Cited by 33 publications

References 10 publications

Sandmeyer reactions. Part 6.1 A mechanistic investigation into the reduction and ligand transfer steps of Sandmeyer cyanation

Sandmeyer reactions. Part 6.1 A mechanistic investigation into the reduction and ligand transfer steps of Sandmeyer cyanation

Kinetic study of the oxidation of ascorbic acid by aqueous copper(II) catalysed by chloride ion *

Outer-Sphere electron-transfer and the effect of linkage isomerism in the titanium(III) reduction of nitro-pentacyanocobaltate(III) and nitro-, and nitrito-pentaamminecobalt(III) complexes in aqueous acidic media

Contact Info

Product

Resources

About