Lyrelle S. Lloyd
Hyperpolarisation through reversible interactions with parahydrogen
Lloyd, Lyrelle S.; Asghar, Aziz; Burns, Michael J.; Charlton, Adrian; Coombes, Steven; Cowley, Michael J.; Dear, Gordon J.; Duckett, Simon B.; Genov, Georgi R.; Green, Gary G. R.; Highton, Louise A. R.; Hooper, Alexander J. J.; Khan, Majid; Khazal, Iman G.; Lewis, Richard. J.; Mewis, Ryan E.; Roberts, Andrew D.; Ruddlesden, Amy J.
Authors
Aziz Asghar
Michael J. Burns
Adrian Charlton
Steven Coombes
Michael J. Cowley
Gordon J. Dear
Simon B. Duckett
Georgi R. Genov
Gary G. R. Green
Louise A. R. Highton
Alexander J. J. Hooper
Majid Khan
Iman G. Khazal
Richard. J. Lewis
Ryan E. Mewis
Andrew D. Roberts
Amy J. Ruddlesden
Abstract
We describe here how the complexes Ir(COD)(NHC)Cl [NHC = IMes, SIMes, IPr, SIPr, ICy, IMe and ImMe2NPri2] provide significant insight into the catalytic process that underpins the hyperpolarization method signal amplification by reversible exchange (SABRE). These complexes react with pyridine and H2 to produce [Ir(H)2(NHC)(py)3]Cl which undergo ligand exchange on a timescale commensurate with good catalytic activity for the signal amplification by reversible exchange effect. This activity results from hydride ligand magnetic inequivalence and is highly dependent on the NHC. Variable temperature and kinetic studies demonstrate that rates of ligand loss which lie between 0.1 and 0.5 sā1 are ideal for catalysis. A role for the solvent complex [Ir(H)2(MeOH)(NHC)(py)2]Cl, which contains chemically inequivalent hydride ligands is revealed in the ligand exchange pathway. By optimisation of the conditions and NHC, a 5500-fold total pyridine signal enhancement is revealed when the NHC is IMes. Both T1-reduction effects and HD exchange with the solvent are probed and shown to link to catalyst efficiency. The resulting signal enhancements suggest future in vivo MRI measurements under physiological conditions using this catalytic effect will be possible.
Citation
Lloyd, L. S., Asghar, A., Burns, M. J., Charlton, A., Coombes, S., Cowley, M. J., Dear, G. J., Duckett, S. B., Genov, G. R., Green, G. G. R., Highton, L. A. R., Hooper, A. J. J., Khan, M., Khazal, I. G., Lewis, R. J., Mewis, R. E., Roberts, A. D., & Ruddlesden, A. J. (2014). Hyperpolarisation through reversible interactions with parahydrogen. Catalysis science & technology, 4(10), 3544-3554. https://doi.org/10.1039/c4cy00464g
Journal Article Type | Article |
---|---|
Acceptance Date | Jul 11, 2014 |
Online Publication Date | Jul 11, 2014 |
Publication Date | Oct 1, 2014 |
Deposit Date | Apr 9, 2019 |
Journal | Catalysis Science and Technology |
Print ISSN | 2044-4753 |
Publisher | Royal Society of Chemistry |
Peer Reviewed | Peer Reviewed |
Volume | 4 |
Issue | 10 |
Pages | 3544-3554 |
DOI | https://doi.org/10.1039/c4cy00464g |
Public URL | https://hull-repository.worktribe.com/output/1563135 |
Publisher URL | https://pubs.rsc.org/en/content/articlelanding/2014/cy/c4cy00464g |
Additional Information | : This document is CrossCheck deposited; : Supplementary Information; : The Royal Society of Chemistry has an exclusive publication licence for this journal; OPEN ACCESS: The accepted version of this article will be made freely available after a 12 month embargo period; : Received 11 April 2014; Accepted 11 July 2014; Accepted Manuscript published 11 July 2014; Advance Article published 4 August 2014; Version of Record published 8 September 2014 |
You might also like
PyBCI: A Python Package for Brain-Computer Interface(BCI) Design
(2023)
Journal Article
Developing research skills in medical students online using an active research study
(2023)
Journal Article
The negative impact of COVID-19 on working memory revealed using a rapid online quiz
(2022)
Journal Article
Downloadable Citations
About Repository@Hull
Administrator e-mail: repository@hull.ac.uk
This application uses the following open-source libraries:
SheetJS Community Edition
Apache License Version 2.0 (http://www.apache.org/licenses/)
PDF.js
Apache License Version 2.0 (http://www.apache.org/licenses/)
Font Awesome
SIL OFL 1.1 (http://scripts.sil.org/OFL)
MIT License (http://opensource.org/licenses/mit-license.html)
CC BY 3.0 ( http://creativecommons.org/licenses/by/3.0/)
Powered by Worktribe © 2025
Advanced Search