From [ 11 C]CO 2 to [ 11 C]amides: a rapid one-pot synthesis via the Mitsunobu reaction.

A novel amide synthesis methodology is described using amines, CO2 and Grignard reagents and Mitsunobu reagents. The method was applied to carbon-11 radiochemistry to label amides using cyclotron-produced [11 C]CO2 . The synthetic utility of the one-pot labelling methodology was demonstrated by producing [11 C]melatonin. The incorporation of [11 C]CO2 into [11 C]melatonin was 36% - determined by radioHPLC 2 min post [11 C]CO2 delivery.