2-[F-18]FLUOROPHENOL AND 4-[F-18]FLUOROPHENOL FROM BAEYER-VILLIGER OXIDATION OF [F-18] FLUOROPHENYLKETONES AND[F-18]FLUOROBENZALDEHYDES

2- or 4-[F-18]Fluorophenols were isolated with 28-40% radiochemical yield (decay corrected, purity > 98%, 35 min synthesis time) from [F-18]fluoroacetophenone and/or [F-18]fluorobenzophenone by a Baeyer-Villiger oxidation using m-chloroperbenzoic acid in the presence of trifluoroacetic acid at 120-130 degrees C for 15 min. This reagent was also able to transform [F-18]fluorobenzaldehydes into the corresponding phenols in 23-25% radiochemical yield (decay corrected, 45 min synthesis time). In order to optimize the synthesis of [F-18]fluorophenols, the [F-18]fluorination of nitrosubstituted benzaldehyde, acetophenone and benzophenone was studied and the results compared with those previously published. Under similar conditions 4-nitrobenzophenone was shown to be the most reactive substrate compared to nitrobenzaldehyde or nitroacetophenone.