Keto-Enol Tautomers Tautomers are isomers which differ in the placement of a hydrogen. One may be converted to the other. ■In base: Step 1:Deprotonation on C Step 2:Reprotonation on O HO: DH +-OH enol form keto form enolate ion (vinyl alcohol) Copyright 2005 Pearson Prentice Hall,Inc.Keto-Enol Tautomers ◼Tautomers are isomers which differ in the placement of a hydrogen. ◼One may be converted to the other. ◼In base: