| Autor: |
Tickner, B. J. (Ben. J.), Ahwal, F. (Fadi), Whitwood, A. C. (Adrian C.), Duckett, S. B. (Simon B.) |
| Jazyk: |
angličtina |
| Rok vydání: |
2020 |
| Předmět: |
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| Popis: |
The substrate scope of sulfoxide‐containing magnetisation transfer catalysts is extended to hyperpolarize α‐ketoisocaproate and α‐ketoisocaproate‐1‐[¹³C]. This is achieved by forming [Ir(H)₂(κ²‐ketoisocaproate)(N‐heterocyclic carbene)(sulfoxide)] which transfers latent magnetism from p‐H₂ via the signal amplification by reversible exchange (SABRE) process. The effect of polarization transfer field on the formation of enhanced ¹³C magnetization is evaluated. Consequently, performing SABRE in a 0.5 μT field enabled most efficient magnetisation transfer. ¹³C NMR signals for α‐ketoisocaproate‐1‐[¹³C] in methanol‐d⁴ are up to 985‐fold more intense than their traditional Boltzmann derived signal intensity (0.8 % ¹³C polarisation). Single crystal X‐ray diffraction reveals the formation of the novel catalyst decomposition products [Ir(μ‐H)(H)₂(IMes)(SO(Ph)(Me)₂)]₂ and [(Ir(H)₂(IMes)(SO(Me)₂))₂(μ‐S)] when the sulfoxides methylphenylsulfoxide and dimethylsulfoxide are used respectively. |
| Databáze: |
OpenAIRE |
| Externí odkaz: |
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