Enols are vinyl alcohols, C=C-OH. It is less stable than the keto form. The keto-enol tautomerization is catalyzed by acids or bases. This makes enols viable intermediates in many important reactions. The most important reaction of enolate anions is nucleophilic addition to the carbonyl group of another molecule of the same or different compound although these reactions may be catalyzed by either acid or base, base catalysis is more common. Enolates are carbanions at the carbon to a carbonyl group; Enolates are powerful nucleophiles with the negative charge spread over a carbon and the oxygen of the carbonyl. Enamines are vinyl amines, C=C-N.