When this iridium compound is used with special hydrogen gas, it can make NMR signals for pyridine much stronger—over 200 times stronger in some cases.
Scientific Claim
The iridium complex IrCl(H)2(COE)(py)2 shows hyperpolarization effects when exposed to parahydrogen, with ortho proton resonance of free pyridine showing >210-fold intensity gain at a 1:8 pyridine ratio and >500-fold at a 1:5.6 ratio.
Original Statement
“When the initial ratio of 1 to py was 1:8, a >210-fold intensity gain in the ortho proton resonance of the free py signal is observed. This enhancement increases to >500-fold when the ligand ratio is 1:5.6 and can be increased further by warming to 313 K; sTable 4 contains data for nicotinamide, nicotine, 5-aminopyrimidine, and 3,5-lutudine to demonstrate scope.”
Evidence Quality Assessment
Claim Status
appropriately stated
Study Design Support
Design supports claim
Appropriate Language Strength
association
Can only show association/correlation
Assessment Explanation
The study reports observed enhancement factors, which is appropriate for describing an association between the catalyst and hyperpolarization effects.
More Accurate Statement
“The iridium complex IrCl(H)2(COE)(py)2 is associated with hyperpolarization effects when exposed to parahydrogen, with ortho proton resonance of free pyridine showing >210-fold intensity gain at a 1:8 pyridine ratio and >500-fold at a 1:5.6 ratio.”