Structural verification and new reactivity for Stang's reagent, [PhI(CN)][OTf]

The structure of Stang's reagent [PhI(CN)][OTf] is confirmed by X-ray crystallography and is determined to be best described as an ion-pair in organic solution. It is found to be a strong Lewis acid, but reaction with pyridine ligands gives [Pyr-CN][OTf] salts via oxidation of pyridine giving a new derivative of the CDAP reagent widely used as an activation agent for polysaccharides.

Automated summary

The structure of Stang's reagent [PhI(CN)][OTf] is confirmed by X-ray crystallography as an ion-pair in organic solution. It is a strong Lewis acid and reacts with pyridine ligands, resulting in the formation of [Pyr-CN][OTf] salts and a new derivative of CDAP reagent commonly used for polysaccharide activation.