The impact of resonance upon both the structure and chemical properties of amides has been recognised since Pauling's seminal treatise on the nature of the chemical bond. 1 Maximisation of this resonance requires planarity of the amide, and while small departures from this may be tolerated without significant energetic penalty (e.g. in many peptidic structures), larger deviations lead to a significant reduction in n N to π* C=O conjugation, and hence unusual structural and chemical properties. Twisted amides have therefore received significant attention as chemists seek to understand and exploit their unique characteristics and reactivity profiles. A prominent example is Kirby's most-twisted amide 1 (Figure , panel a), in which the nitrogen lone pair is perpendicular to the carbonyl π-bond: the resulting lack of resonance manifests in 'aminoketone'-like behaviour structurally (lengthened C-N and shortened C=O bonds), spectroscopically (δ C = 200 ppm for C=O), and in reactivity (rapid hydrolysis at room temperature). More recently, the landmark synthesis of 2quinuclidonium salts such as 2 by Stoltz 5 has enabled experimental quantification of the high basicity of the nitrogen lone pair, 5b which contrasts with the greater basicity on oxygen exhibited by simple amides. While compounds such as 1 and 2 represent the extremes of behaviour of twisted amides, the ability to tune molecular properties such as the relative basicities and hydrogen-bonding capabilities of the oxygen and nitrogen atoms across families of homologous amides is a source of fascination and utility to chemists.