Cross-couplings are an alternative to conventional 11C-methylations which are generally employed in PET tracer synthesis. Therefore, we set out to develop a general procedure for the synthesis of para-11CH3 labeled aromatic amines from the corresponding para-aminoarylboronic esters in the presence of free amines. Aryl boronic esters containing primary, secondary, and tertiary amines were successfully converted into corresponding labeled methyl derivatives in suf¿cient radiochemical yield to apply this
method for tracer development. This procedure was applied to the labeling of CIMBI-712, a promising
candidate for the in vivo imaging of the 5-HT 7 receptor in the CNS