A Method for the Rapid and Simple Measurement of the Magnitude and Relative Sign of 1H-19F Coupling Constants

A novel methodology based on a carbon-selective 1D HSQC experiment is proposed for the determination of H-1-F-19 coupling constants. The method offers rapid access to H-1-F-19 coupling constants that cannot be directly measured from the H-1 NMR spectrum due to the complexity and/or broadening of the proton signals or because the values are very small. As an additional benefit, the method also provides the relative sign of the H-1-F-19 coupling constant.