Enol

Examples of keto-enol tautomerism

Ketone tautomerization, keto-form at left, enol at right. Ex. is 3-pentanone, a less stabilized enol.^{[citation needed]}

Enolate resonance structures, schematic representation of forms (see text regarding molecular orbitals); carbanion form at left, enolate at right; Ex. is 2-butanone, also a less stabilized enol.^{[citation needed]}

Ketone tautomerization, enol-form at left, keto at right. Ex. is 2,4-pentanedione, a hydrogen bond (---) stabilized enol.^{[citation needed]}

Aldehyde tautomerization, enol-form at left, "keto" at right; Ex. is tartronaldehyde (reductone), an enediol-type of enol.^{[citation needed]}

In organic chemistry, enols are a type of Functional group or intermediate in organic chemistry with the formula R₂C=CROH (R = many substituents). The term enol is an abbreviation of alkenol, a portmanteaus deriving from "-ene"/"alkene" and the "-ol". Many kinds of enols are known.^[1]

Keto–enol tautomerism refers to a chemical equilibrium between a "keto" form (a carbonyl, named for the common ketone case) and an enol. The interconversion of the two forms involves the transfer of an alpha hydrogen atom and the reorganisation of bonding electrons. The keto and enol forms are tautomers of each other.^[2]

^ Cite error: The named reference March was invoked but never defined (see the help page).
^ Clayden, Jonathan; Greeves, Nick; Warren, Stuart (2012). Organic chemistry (2nd ed.). New York: Oxford University Press. pp. 450–451. ISBN 978-0-19-927029-3.

[March-1] Cite error: The named reference March was invoked but never defined (see the help page).

[Clayden-2012-2] Clayden, Jonathan; Greeves, Nick; Warren, Stuart (2012). Organic chemistry (2nd ed.). New York: Oxford University Press. pp. 450–451. ISBN 978-0-19-927029-3.

[1]

[2]