Wagner-Meerwein rearrangement

Wagner-Meerwein rearrangement is a class of carbocation 1,2-rearrangement reactions in which a hydrogen, alkyl oraryl group migrates from one carbon to a neighboring carbon.

Several reviews have been published. 

The rearrangement was first discovered in bicyclic terpenes for example the conversion of isoborneol to camphene :
The story of the rearrangement reveals that many scientists were puzzled with this and related reactions and its close relationship to the discovery of carbocations as intermediates.

In a simple demonstration reaction of 1,4-dimethoxybenzene with 2-methyl-2-butanol or 3-methyl-2-butanol in sulfuric acid and acetic acid yield the same disubstituted product :


The related Nametkin rearrangement named after Sergey Namyotkin involves the rearrangement of methyl groups in certain terpenes.
 
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Wagner-Meerwein rearrangement is a class of carbocation 1,2-rearrangement reactions in which a hydrogen, alkyl oraryl group migrates from one carbon to a neighboring carbon.

Several reviews have been published. 

The rearrangement was first discovered in bicyclic terpenes for example the conversion of isoborneol to camphene :
The story of the rearrangement reveals that many scientists were puzzled with this and related reactions and its close relationship to the discovery of carbocations as intermediates.

In a simple demonstration reaction of 1,4-dimethoxybenzene with 2-methyl-2-butanol or 3-methyl-2-butanol in sulfuric acid and acetic acid yield the same disubstituted product :


The related Nametkin rearrangement named after Sergey Namyotkin involves the rearrangement of methyl groups in certain terpenes. In some cases the reaction type is also called a retropinacol rearrangement (see Pinacol rearrangemen
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