Beckmann reaction of oximes catalysed by chloral: mild and neutral procedures

A variety of ketoximes undergo the Beckmann rearrangement when heated with 0.5 molar equiv. of chloral (neat melt/∼130°C), to furnish the corresponding amides in excellent yields (generally 80–95%) after simple work-up. (Aromatic aldoximes dehydrated to the corresponding nitriles in excellent yields under similar conditions.) The absence of solvent, Brønsted acids, strong Lewis acids and by-products, and a simple work-up characterise the procedures.