Hg(OTf)2-CatalyzedInstantaneous Hydration of β- and δ-Hydroxy Internal Alkyneswith Complete Regioselectivity

The hydration of β- and 6-hydroxy internal alkynes catalyzed by Hg(OTf) 2 took place instantaneously to give ketones with complete regioselectivity under mild conditions, whereas the hydration of internal alkyne without hydroxy moiety was very slow and gave a mixture of ketones. If the hydroxy group is located more than five carbons from the triple bond it has no significant effect upon the hydration reaction.