Purple Light-Promoted Ferrier Photobromination of O -Benzoylated Carbohydrates in Benzotrifluoride

Our laboratory has previously reported on a contemporary Ferrier photobromination which circumvents critical limitations of the original reaction. The new conditions provide highly efficient and scalable routes to O-acetylated 5-C-bromosugars but cannot be used to access O-benzoylated derivatives. Herein, we show that the scope of the Ferrier photobromination can be expanded to encompass important O-benzoylated carbohydrates by a simple but effective modification of the reaction conditions. This advance importantly paves the way for improved syntheses of glycosidase inhibitors and rare L-hexoses.