The catalytic activity of different classes of boron catalysts was studied in amidation reactions with 4-phenylbutylamine/benzoic acid, and with 2-aminopyridine/phenylacetic acid. Whilst a simple boronic acid catalyst showed high catalytic activity with the former substrates, it was completely inactive in the latter reaction. In contrast, a borate ester catalyst was able to mediate the amidation of both substrate pairs with moderate activity. By screening a range of borate esters we were able to identify a novel borate catalyst that shows high reactivity with a range of challenging carboxylic acids/amine pairs, enabling catalystic amidation reactions to be achieved effectively with these industrially relevant compounds. The reactions can be performed on multigram scale with high levels of efficiency, and