Abstract
The short lived pincer complex [(C5H3N(CH2P(Bu-t)(2))(2))Ir(H)(2)(py)]BF4 is shown to be active for signal amplification by reversible exchange. This catalyst formulation enables the efficient transfer of polarization from parahydrogen to be placed into just a single molecule of the hyperpolarisation target, pyridine. When the catalysts H-1 nuclei are replaced by H-2, increased levels of substrate hyperpolarization result and when the reverse situation is examined the catalyst itself is clearly visible through hyperpolarised signals. The ligand exchange pathways of [(C5H3N(CH2P(Bu-t)(2))(2))Ir(H)(2)(py)]BF4 that are associated with this process are shown to involve the formation of 16-electron [(C5H3N(CH2P(Bu-t)(2))(2))Ir(H)(2)(py)]BF4 and the 18-electron H-2 addition product [(C5H3N(CH2P(Bu-t)(2))(2))Ir(H)(2)(py)]BF4.
Original language | English |
---|---|
Pages (from-to) | 1077-1083 |
Number of pages | 7 |
Journal | Dalton Transactions |
Volume | 44 |
Issue number | 3 |
DOIs | |
Publication status | Published - 2015 |
Keywords / Materials (for Non-textual outputs)
- HYDROGEN INDUCED POLARIZATION
- PINCER COMPLEXES
- NUCLEAR-POLARIZATION
- NMR-SPECTROSCOPY
- BOND ACTIVATION
- SPIN
- RHODIUM
- FIELD
- DIHYDROGEN
- MECHANISM