On changing the coupling partner from an aryl iodide to an aryl bromide, the formation of the diarylated product was no longer observed (Scheme 2). Electron withdrawing directing groups gave lower overall yields of the arylated products (2e and 2f) and higher yields were seen with the unsubstituted picolinamide and substrates bearing electron donating groups (2a-2c and 2h). This monoarylation reaction almost certainly provides a better reflection of the inherent reactivity of each directing group in terms of facilitating the catalytic cycle. The improved efficency of the reaction with 3-methylpicolinamide perhaps reflects conformational effects on the palladium complexation/decomplexation steps which enable better catalytic turnover. More generally, electrondonating substituents on the picolinamide are clearly preferable to electron-withdrawing substituents in terms of reaction efficiency. Again, the 3-methylpicolinamide 1b gave the highest yield of monoarylated product. Subsequent results (vide infra, Scheme 5) suggested that bromide ions could suppress C-H activation processes, so this is probably the reason why no arylation of the methyl group is observed in these reactions.