Synthesis of No-Carrier-Added 4-[18F]Fluorophenol from 4-Benzyloxyphenyl-(2-thienyl)iodonium Bromide

4-[F-18]Fluorophenol is a versatile synthon for the synthesis of more complex radiopharmaceuticals bearing a 4-[F-18]fluorophenoxy moiety. In order to prepare 4-[F-18]fluorophenol in no-carrier-added (n.c.a.) form only a nucleophilic labelling method starting from [F-18]fluoride is suitable. In this paper a new, two step radiosynthesis starting from 4-benzyloxyphenyl-(2-thienyl) iodonium bromide and [F-18]fluoride with subsequent deprotection is described, yielding n.c.a. [F-18]fluorophenol in 34 to 36% radiochemical yield.