Waiting
Login processing...

Trial ends in Request Full Access Tell Your Colleague About Jove

10.10: Preparación de Dioles y Reordenamiento Pinacol
TABLA DE
CONTENIDOS

JoVE Core
Organic Chemistry

A subscription to JoVE is required to view this content.
You will only be able to see the first 20 seconds.

Education
Preparación de Dioles y Reordenamiento Pinacol
 
TRANSCRIPCIÓN

10.10: Preparación de Dioles y Reordenamiento Pinacol

Compounds bearing two hydroxyl groups are known as diols. When the hydroxyl groups are located on adjacent carbon atoms, the diols are called vicinal diols or glycols. Under acidic conditions, vicinal diols undergo a specific reaction called pinacol rearrangement.

The reaction begins with transferring a proton from the acid catalyst to one of the hydroxyl groups, producing an oxonium ion.

Figure1

In the second step, the oxonium ion loses H2O, forming a tertiary carbocation intermediate.

Figure2

In the following step, a methyl group migrates from one carbon to the adjacent carbon, producing a resonance-stabilized cation intermediate where carbon and oxygen have complete octets of valence electrons.

Figure3

Finally, the subsequent proton transfer from the resonance-stabilized cation intermediate to the solvent water completes the reaction to give pinacolone.

Figure4

Since the reaction causes an overall change in the carbon backbone, it is termed a rearrangement.

Get cutting-edge science videos from JoVE sent straight to your inbox every month.

Waiting X
Simple Hit Counter