Abstract: Compound 1 is a potent and selective antagonist of the dopamine D3 receptor. With the aim of developing a carbon-11 labeled ligand for the dopamine D3 receptor, 1 was selected as a potential PET probe. [11C]1 was obtained by palladium catalyzed cross coupling using [11C]cyanide and 4 with a specific activity of 55.5±25.9GBq/μmol (1.5±0.7Ci/μmol). [11C]1 was tested in porcine and non-human primate models to assess its potential as a radioligand for PET imaging of the dopamine D3 receptor. We conclude that in both species and despite appropriate in vitro properties, [11C]1 does not show any specific signal for the dopamine D3 receptor. [Copyright &y& Elsevier]