Chemoselective O-Benzylation of the Propargylic Hydroxy Group in Polyols

We have discovered the highly chemoselective benzylation of propargylic hydroxy groups in the presence of other hydroxy groups under very usual conditions involving benzyl bromide and sodium hydroxide in DMF at room temperature. This methodology has a high synthetic utility for the selective protection of hydroxy groups at the propargylic position among various other hydroxy groups in complex molecules.