Pages

Tuesday 30 April 2013

Alder-Ene Reaction Ene Reaction

Alder-Ene Reaction
Ene Reaction


The four-electron system including an alkene π-bond and an allylic C-H σ-bond can participate in a pericyclic reaction in which the double bond shifts and new C-H and C-C σ-bonds are formed. This allylic system reacts similarly to a diene in a Diels-Alder Reaction, while in this case the other partner is called an enophile, analogous to the dienophile in the Diels-Alder. The Alder-Ene Reaction requires higher temperatures because of the higher activation energy and stereoelectronic requirement of breaking the allylic C-H σ-bond.
The enophile can also be an aldehyde, ketone or imine, in which case β-hydroxy- or β-aminoolefins are obtained. These compounds may be unstable under the reaction conditions, so that at elevated temperature (>400°C) the reverse reaction takes place - the Retro-Ene Reaction.
While mechanistically different, the Ene reaction can produce a result similar to the Prins Reaction.

Mechanism of the Alder-Ene Reaction

No comments:

Post a Comment

 

Sample text

Sample Text