Application of the nucleophilic substitution reaction to the synthesis of No‐carrier‐added [18F]fluorobenzene and other 18F‐labeled aryl fluorides

No‐carrier‐added (NCA) [18F]fluorobenzene was prepared in a multistep synthesis with a radiochemical yield of 20‐30%. A series of NCA and CA 18F‐labeled aryl fluorides which are important precursors of 18F‐labeled butyrophenone neuroleptics have also been synthesized in radiochemical yields of 30–50%. The direct synthesis of [18F]spiroperidol and [18F]benperidol from the parent compounds and/or nitro and/or chloro compound using the nucleophilic substitution reactions were also investigated.