How to introduce radioactive chlorine into a benzene ring using [*Cl]Cl−?

The aim of this study was how to introduce radioactive chlorine (*Cl) isotope into a benzene ring to afford *Cl-labeled chlorobenzene ([*Cl]1). Using tributylphenylstannyl compound (2) as a starting material, we determined two routes for introducing *Cl into the benzene ring: reaction of [*Cl]Cl− with 2 in the presence of chloramine-T and nucleophilic reaction of [*Cl]Cl− with diphenyliodonium tosylate (3). The two routes provide suitable tools to prepare [*Cl]1 without electron-abstracting group in the benzene ring.