An efficient one-pot synthesis of [C-11]ureas and [C-11]isocyanates via deh
ydration of intermediately formed carbamate salts is described as a general
alternative to their formation via [C-11]phosgene. After optimization of t
he reaction parameters, in-target produced n.c.a. [C-11]CO2 can be used for
labelling in a one pot reaction within a very short reaction time of 10 mi
nutes resulting in good radiochemical yields. The developed method has been
applied to the C-11-carbonylation of aniline, benzyl- and phenethylamine a
nd 1,2-diaminobenzene yielding the appropriate n.c.a. [C-11]ureas in about
65, 85, 25 and 70% radiochemical yield (RCY), respectively. The presented r
eaction sequence can be handled easily and safely and lends itself to simpl
e automation.