Tritium labelling of two potent dopamine D2 receptor agonists at high specific activity

Highlights: • This paper describes the tritium radiolabelling of two potent dopamine D2 receptor agonists. • A common and efficient synthetic route is outlined for these compounds that is both robust and scalable. • The products are prepared at high radiopurity and specific activity. An efficient method is described to radiolabel several dopamine D₂ receptor agonists with tritium at high specific activity.