Interpretation:
Determine the mechanism for the cleavage of β-cyanoethyl protective group by using aqueous ammonia and state the type of occurring reaction.
Concept introduction:
The cleavage of β-cyanoethyl protective group occurs according to the β-elimination mechanism. In β-elimination mechanism, the bond β to the nucleophilic pair of electrons breaks. The elimination reaction involves the breaking of the sigma (σ) bond and the formation of new pie (π) bond. In this process a lone pair electron forms a double bond as the leaving group departs.
Given information:
The cleavage of β-cyanoethyl protective group can be done by aqueous ammonia. The by-product of this reaction is acrylonitrile.
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- Organic ChemistryChemistryISBN:9781305580350Author:William H. Brown, Brent L. Iverson, Eric Anslyn, Christopher S. FootePublisher:Cengage Learning