Electrochemical reduction of CO2 catalyzed by a dinuclear palladium complex containing a bridging hexaphosphine ligand

Evidence for cooperativity

Bryan D. Steffey, Calvin J. Curtis, Daniel L. DuBois

Research output: Contribution to journalArticle

52 Citations (Scopus)

Abstract

The complexes [Pd2(CH3CN)2(eHTP)](BF4)4 and [Pd2(PEt3)2(eHTP)](BF4)4 (where eHTP is bis(bis((diethylphosphino)ethyl)phosphino))methane, (Et2PCH2CH2)2PCH 2P(CH2CH2PEt2)2) were prepared and characterized. [Pd2(CH3CN)2(eHTP)](BF4)4 catalyzes the electrochemical reduction of CO2 to CO in acidic dimethylformamide solutions. The rate of this reaction exhibits a biphasic dependence on acid, with a first-order dependence at low acid concentrations and zero-order dependence at acid concentrations greater than 0.06 M. At high acid concentrations the rate-limiting step is first order in catalyst and first order in CO2. When compared to the kinetic properties of previously studied mononuclear complexes, these data suggest both palladium atoms are involved in CO2 reduction. The closely related complex [Pd2(PEt3)2(eHTP)](BF4)4 undergoes two reversible two-electron reductions. The mixed-valence intermediate resulting from the first two-electron reduction is unstable and undergoes rapid decomposition.

Original languageEnglish
Pages (from-to)4937-4943
Number of pages7
JournalOrganometallics
Volume14
Issue number10
Publication statusPublished - 1995

Fingerprint

Palladium
palladium
Ligands
ligands
acids
Acids
Dimethylformamide
Electrons
Methane
Carbon Monoxide
electrons
methane
Decomposition
valence
decomposition
catalysts
Atoms
Catalysts
Kinetics
kinetics

ASJC Scopus subject areas

  • Inorganic Chemistry
  • Organic Chemistry

Cite this

Electrochemical reduction of CO2 catalyzed by a dinuclear palladium complex containing a bridging hexaphosphine ligand : Evidence for cooperativity. / Steffey, Bryan D.; Curtis, Calvin J.; DuBois, Daniel L.

In: Organometallics, Vol. 14, No. 10, 1995, p. 4937-4943.

Research output: Contribution to journalArticle

@article{2c41bd26a947466ab6b25aec7ea1f7d1,
title = "Electrochemical reduction of CO2 catalyzed by a dinuclear palladium complex containing a bridging hexaphosphine ligand: Evidence for cooperativity",
abstract = "The complexes [Pd2(CH3CN)2(eHTP)](BF4)4 and [Pd2(PEt3)2(eHTP)](BF4)4 (where eHTP is bis(bis((diethylphosphino)ethyl)phosphino))methane, (Et2PCH2CH2)2PCH 2P(CH2CH2PEt2)2) were prepared and characterized. [Pd2(CH3CN)2(eHTP)](BF4)4 catalyzes the electrochemical reduction of CO2 to CO in acidic dimethylformamide solutions. The rate of this reaction exhibits a biphasic dependence on acid, with a first-order dependence at low acid concentrations and zero-order dependence at acid concentrations greater than 0.06 M. At high acid concentrations the rate-limiting step is first order in catalyst and first order in CO2. When compared to the kinetic properties of previously studied mononuclear complexes, these data suggest both palladium atoms are involved in CO2 reduction. The closely related complex [Pd2(PEt3)2(eHTP)](BF4)4 undergoes two reversible two-electron reductions. The mixed-valence intermediate resulting from the first two-electron reduction is unstable and undergoes rapid decomposition.",
author = "Steffey, {Bryan D.} and Curtis, {Calvin J.} and DuBois, {Daniel L.}",
year = "1995",
language = "English",
volume = "14",
pages = "4937--4943",
journal = "Organometallics",
issn = "0276-7333",
publisher = "American Chemical Society",
number = "10",

}

TY - JOUR

T1 - Electrochemical reduction of CO2 catalyzed by a dinuclear palladium complex containing a bridging hexaphosphine ligand

T2 - Evidence for cooperativity

AU - Steffey, Bryan D.

AU - Curtis, Calvin J.

AU - DuBois, Daniel L.

PY - 1995

Y1 - 1995

N2 - The complexes [Pd2(CH3CN)2(eHTP)](BF4)4 and [Pd2(PEt3)2(eHTP)](BF4)4 (where eHTP is bis(bis((diethylphosphino)ethyl)phosphino))methane, (Et2PCH2CH2)2PCH 2P(CH2CH2PEt2)2) were prepared and characterized. [Pd2(CH3CN)2(eHTP)](BF4)4 catalyzes the electrochemical reduction of CO2 to CO in acidic dimethylformamide solutions. The rate of this reaction exhibits a biphasic dependence on acid, with a first-order dependence at low acid concentrations and zero-order dependence at acid concentrations greater than 0.06 M. At high acid concentrations the rate-limiting step is first order in catalyst and first order in CO2. When compared to the kinetic properties of previously studied mononuclear complexes, these data suggest both palladium atoms are involved in CO2 reduction. The closely related complex [Pd2(PEt3)2(eHTP)](BF4)4 undergoes two reversible two-electron reductions. The mixed-valence intermediate resulting from the first two-electron reduction is unstable and undergoes rapid decomposition.

AB - The complexes [Pd2(CH3CN)2(eHTP)](BF4)4 and [Pd2(PEt3)2(eHTP)](BF4)4 (where eHTP is bis(bis((diethylphosphino)ethyl)phosphino))methane, (Et2PCH2CH2)2PCH 2P(CH2CH2PEt2)2) were prepared and characterized. [Pd2(CH3CN)2(eHTP)](BF4)4 catalyzes the electrochemical reduction of CO2 to CO in acidic dimethylformamide solutions. The rate of this reaction exhibits a biphasic dependence on acid, with a first-order dependence at low acid concentrations and zero-order dependence at acid concentrations greater than 0.06 M. At high acid concentrations the rate-limiting step is first order in catalyst and first order in CO2. When compared to the kinetic properties of previously studied mononuclear complexes, these data suggest both palladium atoms are involved in CO2 reduction. The closely related complex [Pd2(PEt3)2(eHTP)](BF4)4 undergoes two reversible two-electron reductions. The mixed-valence intermediate resulting from the first two-electron reduction is unstable and undergoes rapid decomposition.

UR - http://www.scopus.com/inward/record.url?scp=0000358793&partnerID=8YFLogxK

UR - http://www.scopus.com/inward/citedby.url?scp=0000358793&partnerID=8YFLogxK

M3 - Article

VL - 14

SP - 4937

EP - 4943

JO - Organometallics

JF - Organometallics

SN - 0276-7333

IS - 10

ER -