Harnessing polarisation transfer to indazole and imidazole through signal amplification by reversible exchange to improve their NMR detectability

Bibliographische Detailangaben
Veröffentlicht in:	Magnetic resonance in chemistry : MRC. - 1985. - 55(2017), 10 vom: 24. Okt., Seite 944-957
1. Verfasser:	Fekete, Marianna (VerfasserIn)
Weitere Verfasser:	Rayner, Peter J, Green, Gary G R, Duckett, Simon B
Format:	Online-Aufsatz
Sprache:	English
Veröffentlicht:	2017
Zugriff auf das übergeordnete Werk:	Magnetic resonance in chemistry : MRC
Schlagworte:	Journal Article SABRE imidazole indazole iridium catalyst

Beschreibung
Zusammenfassung:	Copyright © 2017 The Authors. Magnetic Resonance in Chemistry published by John Wiley & Sons Ltd. The signal amplification by reversible exchange (SABRE) approach has been used to hyperpolarise the substrates indazole and imidazole in the presence of the co-ligand acetonitrile through the action of the precataysts [IrCl(COD)(IMes)] and [IrCl(COD)(SIMes)]. 2 H-labelled forms of these catalysts were also examined. Our comparison of the two precatalysts [IrCl(COD)(IMes)] and [IrCl(COD)(SIMes)], coupled with 2 H labelling of the N-heterocyclic carbene and associated relaxation and polarisation field variation studies, demonstrates the critical and collective role these parameters play in controlling the efficiency of signal amplification by reversible exchange. Ultimately, with imidazole, a 700-fold1 H signal gain per proton is produced at 400 MHz, whilst for indazole, a 90-fold increase per proton is achieved. The co-ligand acetonitrile proved to optimally exhibit a 190-fold signal gain per proton in these measurements, with the associated studies revealing the importance the substrate plays in controlling this value. Copyright © 2017 The Authors. Magnetic Resonance in Chemistry published by John Wiley & Sons Ltd
Beschreibung:	Date Completed 05.03.2018 Date Revised 16.02.2024 published: Print-Electronic Citation Status PubMed-not-MEDLINE
ISSN:	1097-458X
DOI:	10.1002/mrc.4607