A synthetic pathway for PET-labeled amides is described using rhodium-catalyzed coupling of organozinc iodide reagents and in situ prepared carbon-11 isocyanates. A scope prepared using carbon-12 isocyanates yielded products from 13-87% using readily prepared sp 3 and sp 2 organozinc iodides. By manipulation of fixation, dehydration, and coupling conditions, the incorporation of [ 11 C]CO2 into 11 C-amide products proceeded in moderate to strong yields, as determined by radioHPLC. Among the compounds prepared are the biologically-relevant tert-butyl protected [ 11 C]N-acetyl glutamic acid ([ 11 C]6d), the agrochemical [ 11 C]propanil ([ 11 C]6f), and a pharmaceutically-relevant [ 11 C]acetanilide ([ 11 C]4m). The synthetic utility of the labeling methodology was demonstrated through the isolation of [ 11 C]N-(4-fluorophenyl)-4-methoxybenzamide ([ 11 C]6g) with a molar activity of 267 GBq•mol -1 and a radioactivity yield of 12%, 21 minutes after beginning of synthesis.

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