Catalytic Staudinger—Vilarrasa Reaction for the Direct Ligation of Carboxylic Acids and Azides

Abstract
2,2'-Dipyridyl diselenide (PySeSePy) is the catalyst or activator of choice for the direct reaction of carboxylic acids with azides and trimethylphosphine at room temperature. The mechanism of the process, which is not an aza-Wittig reaction, has been elucidated.