Curtin University Homepage
  • Library
  • Help
    • Admin

    espace - Curtin’s institutional repository

    JavaScript is disabled for your browser. Some features of this site may not work without it.
    View Item 
    • espace Home
    • espace
    • Curtin Research Publications
    • View Item
    • espace Home
    • espace
    • Curtin Research Publications
    • View Item

    Electrochemical and Electrostatic Cleavage of Alkoxyamines

    65593.pdf (870.7Kb)
    Access Status
    Open access
    Authors
    Zhang, L.
    Laborda, E.
    Darwish, Nadim
    Noble, B.
    Tyrell, J.
    Pluczyk, S.
    Le Brun, A.
    Wallace, G.
    Gonzalez, J.
    Coote, M.
    Ciampi, Simone
    Date
    2018
    Type
    Journal Article
    
    Metadata
    Show full item record
    Citation
    Zhang, L. and Laborda, E. and Darwish, N. and Noble, B. and Tyrell, J. and Pluczyk, S. and Le Brun, A. et al. 2018. Electrochemical and Electrostatic Cleavage of Alkoxyamines. Journal of the American Chemical Society. 140 (2): pp. 766-774.
    Source Title
    Journal of the American Chemical Society
    DOI
    10.1021/jacs.7b11628
    ISSN
    0002-7863
    School
    Nanochemistry Research Institute
    Funding and Sponsorship
    http://purl.org/au-research/grants/arc/DE160100732
    http://purl.org/au-research/grants/arc/DE160101101
    URI
    http://hdl.handle.net/20.500.11937/65431
    Collection
    • Curtin Research Publications
    Abstract

    © 2017 American Chemical Society. Alkoxyamines are heat-labile molecules, widely used as an in situ source of nitroxides in polymer and materials sciences. Here we show that the one-electron oxidation of an alkoxyamine leads to a cation radical intermediate that even at room temperature rapidly fragments, releasing a nitroxide and carbocation. Digital simulations of experimental voltammetry and current-time transients suggest that the unimolecular decomposition which yields the "unmasked" nitroxide (TEMPO) is exceedingly rapid and irreversible. High-level quantum computations indicate that the collapse of the alkoxyamine cation radical is likely to yield a neutral nitroxide radical and a secondary phenylethyl cation. However, this fragmentation is predicted to be slow and energetically very unfavorable. To attain qualitative agreement between the experimental kinetics and computational modeling for this fragmentation step, the explicit electrostatic environment within the double layer must be accounted for. Single-molecule break-junction experiments in a scanning tunneling microscope using solvent of low dielectric (STM-BJ technique) corroborate the role played by electrostatic forces on the lysis of the alkoxyamine C-ON bond. This work highlights the electrostatic aspects played by charged species in a chemical step that follows an electrochemical reaction, defines the magnitude of this catalytic effect by looking at an independent electrical technique in non-electrolyte systems (STM-BJ), and suggests a redox on/off switch to guide the cleavage of alkoxyamines at an electrified interface.

    Related items

    Showing items related by title, author, creator and subject.

    • Development of an electrostatically assisted solvent extraction column
      Steffens, Marc J. (2011)
      Solvent extraction (SX) is the only commercially viable hydrometallurgical separation and purification technique for a range of metals that allows high product throughput and consistently high recoveries. After over 50 ...
    • Effect of pulsed electrostatic fields on mass transfer in a modified Lewis cell
      Assmann, Simon; Ibana, Don; McRae, C. (2011)
      Electrostatic solvent extraction (ESX) promises to circumvent many of the weaknesses of the current solvent extraction (SX) technology, but commercial application of the technique has not been achieved. This is partly ...
    • Harnessing electrostatic catalysis in single molecule, electrochemical and chemical systems: a rapidly growing experimental tool box.
      Ciampi, S.; Darwish, Nadim; Aitken, H.; Díez-Pérez, I.; Coote, M. (2018)
      Static electricity is central to many day-to-day practical technologies, from separation methods in the recycling of plastics to transfer inks in photocopying, but the exploration of how electrostatics affects chemical ...
    Advanced search

    Browse

    Communities & CollectionsIssue DateAuthorTitleSubjectDocument TypeThis CollectionIssue DateAuthorTitleSubjectDocument Type

    My Account

    Admin

    Statistics

    Most Popular ItemsStatistics by CountryMost Popular Authors

    Follow Curtin

    • 
    • 
    • 
    • 
    • 

    CRICOS Provider Code: 00301JABN: 99 143 842 569TEQSA: PRV12158

    Copyright | Disclaimer | Privacy statement | Accessibility

    Curtin would like to pay respect to the Aboriginal and Torres Strait Islander members of our community by acknowledging the traditional owners of the land on which the Perth campus is located, the Whadjuk people of the Nyungar Nation; and on our Kalgoorlie campus, the Wongutha people of the North-Eastern Goldfields.