Syntheses of [/sup 18/F] aryl fluorides by fluorination of aryltrimethylsilanes or arylpentafluorosilicates with [/sup 18/F]F/sub 2/ or [/sup 18/F]CH/sub 3/CO/sub 2/F

F-18 Aryl fluorides are the important intermediates for the syntheses of F-18 labeled radiopharmaceuticals. F-18 Labeled aryl fluorides have been synthesized either from [/sup 18/F]F/sub 2/ or [/sup 18/F]fluoride. The authors report here the syntheses of [/sup 18/F]aryl fluorides by fluorination of aryltrimethylsilanes (1) or arylpentaflurorsilicates (2) with [/sup 18/F]F/sub 2/ or [/sup 18/F]CH/sub 3/CO/sub 2/F. Fluorination of compounds (1) with either [/sup 18/F]F/sub 2/ or [/sup 18/F]CH/sub 3/CO/sub 2/F give the corresponding aryl fluorides (3) and the aryltrimethylsilyl fluorides (4) in 2-10% yields depending on the reaction conditions. Compounds (2) and (3) can easily be separate by HPLC or GLC. Treatment of compounds (4) with HClO/sub 4/-MeOH (1:1) give the corresponding desilylated compounds (3underscore). Fluorination of compounds (2) with [/sup 18/F]CH/sub 3/CO/sub 2/F give the corresponding aryl fluorides (3) in 10-20% yield. The yields of compounds (3) and (4) depend on the reaction conditions. Lower temperature (-760C in freon vs 250C in CH/sub 3/CO/sub 2/H) favors the formation of aryl fluorides, [/sup 18/F]F/sub 2/ gives a better yield of aryl fluorides than with [/sup 18/F]CH/sub 3/CO/sub 2/F, and the electron-withdrawing groups are in favor of aryl fluoride formations. This method thus provides an alternative route to F-18 labeled radiopharmaceuticals such as p-/sup 18/F]fluorohippuric acid which is otherwise difficult to prepare, and other F-18 labeled neuroleptics