Nickel-Mediated Radioiodination of Aryl and Heteroaryl Bromides: Rapid Synthesis of Tracers for SPECT Imaging†

Rapid and efficient radioiodination of aryl and heteroaryl bromides has been achieved using a nickel(0)-mediated halogen-exchange reaction. This transformation gives direct access to [123I]- and [ 125I]-imaging agents for single photon emission computed tomography (SPECT), such as 5-[123I]-A85380 (see scheme, Boc=tert- butyloxycarbonyl, cod=1,5-cyclooctadiene, TFA=trifluoroacetic acid).