Parahydrogen-Induced Polarization Transfer to super(19)F in Perfluorocarbons for super(19)FNMR Spectroscopy and MRI

Fluorinated substances are important in chemistry, industry, and the life sciences. In a new approach, parahydrogen-induced polarization (PHIP) is applied to enhance super(19)FMR signals of (perfluoro-n-hexyl)ethene and (perfluoro-n-hexyl)ethane. Unexpectedly, the end-standing CF sub(3) group exhibits the highest amount of polarization despite the negligible coupling to the added protons. To clarify this non-intuitive distribution of polarization, signal enhancements in deuterated chloroform and acetone were compared and super(19)F- super(19) FNOESY spectra, as well as super(19)F T sub(1) values were measured by NMR spectroscopy. By using the well separated and enhanced signal of the CF sub(3) group, first super(19)FMR images of hyperpolarized linear semifluorinated alkenes were recorded. Fluorinated substances are important in chemistry and the life sciences. In a new approach, parahydrogen-induced polarization (PHIP) is applied to enhance super(19)FMR signals of (perfluoro-n-hexyl)ethene and (perfluoro-n-hexyl)ethane. This allows super(19)FMR imaging of hyperpolarized linear semifluorinated alkenes (see picture). Unexpectedly, the end-standing CF sub(3) group exhibits the highest amount of polarization despite the negligible coupling to the added protons.