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: OH +OH H enol form keto form enolate ion (vinyl alcohol) Copyright2005 Pearson Prentice Hall,Inc. => Chapter 22 5 Chapter 22 5 Keto-Enol Tautomers • Tautomers are isomers which differ in the placement of a hydrogen. • One may be converted to the other. • In base: =>