Mechanistic insight into novel sulfoxide containing SABRE polarisation transfer catalysts. Issue 40 (2nd October 2019)

• Record Type: Journal Article
• Authors: Tickner, Ben. J.; Lewis, Jennifer S.; John, Richard O.; Whitwood, Adrian C.; Duckett, Simon B.
• Is Part Of: Dalton transactions. Volume 48:Issue 40(2019)
• Page Start: 15198
• Page End: 15206
• Publication Date: 2019-10-02
• Subjects: Chemistry, Inorganic -- Periodicals; Chemistry, Physical and theoretical -- Periodicals; Chemistry, Inorganic -- Periodicals; 546.05
• DOI: 10.1039/c9dt02951f
• Languages: English
• ISSNs: 1477-9226

Abstract

Abstract : Mechanistic investigation of sulfoxide based catalysts used to transfer magnetisation from para -hydrogen to pyruvate and oxalate in SABRE. Abstract : Signal Amplification By Reversible Exchange (SABRE) is a hyperpolarisation technique that commonly uses [Ir(H)2 (carbene)(substrate)3 ]Cl complexes to catalytically transfer magnetisation from para -hydrogen derived hydride ligands to coordinated substrates. Here, we explore the reactivity of a novel class of such catalysts based on sulfoxide containing [IrCl(H)2 (carbene)(DMSO)2 ], which are involved in the hyperpolarisation of pyruvate using SABRE. We probe the reactivity of this species by NMR and DFT and upon reaction with sodium pyruvate establish the formation of two isomers of [Ir(H)2 (η 2 -pyruvate)(DMSO)(IMes)]. Studies with related disodium oxalate yield [Ir2 (H)4 (IMes)2 (DMSO)2 (η 2 -κ 2 -Oxalate)] that is characterised by NMR and X-ray diffraction.