Oxidations of Alcohols, Aldehydes, and Diols Using NaBr and Selectfluor

Abstract

We present protocols for the oxidation of alcohols and aldehydes and for the oxidative cyclization of diols which use a combination of Selectfluor and NaBr. For most substrates, the optimal solvent system is a 1:1 mixture of CH₃CN/H₂O, but, in select cases, biphasic 1:1 mixtures of EtOAc/H₂O or CH₂Cl₂/H₂O are superior. This procedure is operationally simple, uses inexpensive and readily available reagents, and tolerates a variety of functional groups. Mechanistic studies suggest that the active oxidant is hypobromous acid, generated by the almost instantaneous oxidation of Br^- by Selectfluor in an aqueous milieu.