Manchester NMR Methodology Group

DOSY works best when there is no spectral overlap between components, so drugs containing fluorine substituents are well-suited for DOSY analysis as 19F spectra are typically very sparse. Here, we demonstrate the use of a modified 19F DOSY experiment (on the basis of the Oneshot sequences) for various fluorinated benzenes. For compounds with significant nJFF coupling constants, as is common, the undesirable J-modulation can be efficiently suppressed using the Oneshot45 pulse sequence. This investigation highlights 19F DOSY as a valuable and robust method for analysis of molecular systems containing fluorine atoms even where there are large fluorine–fluorine couplings.