Prediction of 19F NMR Chemical Shifts for Fluorinated Aromatic Compounds

Scaling factors are reported for use in predicting 19F NMR chemical shifts for fluorinated (hetero)­aromatic compounds with relatively low levels of theory. Our recommended scaling factors were developed using a curated data set of 52 compounds, with 100 individual 19F shifts spanning a range of 153 ppm. With a maximum deviation of 6.5 ppm between experimental and computed shifts, or 4% of the range tested, these scaling factors allow for the assignment of chemical shifts to specific fluorines in multifluorinated aromatics. The utility of this approach is highlighted by several structural reassignments.