Leaving group effects half-life

The formation of organic fluorides has been a difficult undertaking. However, an investigation of the effect of the solvent, leaving group, and source of the fluoride ion has shown that using tetrabutylammonium fluoride or CsF in r-amyl alcohol is able to convert arene sulfonates into fluorides rapidly at 90 °C in excellent yields (>80%).65 Since the half-life of 18F is only 110 min, this is an important advance as it allows one to label compounds with 18F for PET studies. 

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