Keto-Enol Tautomers keto form enol form (99.99%) (0.01%) Tautomerization is an interconversion of isomers that occur through the migration of a proton and the movement of a double bond. Tautomers are not resonance form. Chapter 22 5Chapter 22 5 Keto–Enol Tautomers O H H OH H keto form (99.99%) enol form (0.01%) ▪ Tautomerization is an interconversion of isomers that occur through the migration of a proton and the movement of a double bond. ▪ Tautomers are not resonance form