Kornblum–DeLaMare rearrangement

The base can be a hydroxide such as potassium hydroxide or an amine such as triethylamine.

Reaction mechanism

In the reaction mechanism for this organic reaction the base abstracts the acidic α-proton of the peroxide 1 to form the carbanion 4 as a reactive intermediate which rearranges to the ketone 2 with expulsion of the hydroxyl anion 3'. This intermediate gains a proton forming the alcohol 3.

Deprotonation and rearrangement can also be a concerted reaction without formation of 4.

An alternative reaction mechanism involving direct nucleophilic displacement on the peroxide link of the amine followed by an elimination reaction is considered unlikely based on the outcome of this model reaction:

The peroxide 1 converts to the hydroxyketone 2 by action of triethylamine but the alternative route through hydroxylamine 3 by nucleophilic displacement with Lithium diisopropylamide and the ammonium salt 4 (by methylation with methyl trifluoromethanesulfonate) fails.

The reaction, formally a rearrangement, ranks under the elimination reactions as already observed by the original authors. Not only alkoxides but any leaving group capable of carrying a negative charge will do for instance nitrate esters R–C(R)(H)–O–NO₂.