Interpretation:
Whether the product obtained by the bromination of optically active (R)-2-phenylpropanoic acid under Hell-Volhard-Zelinski conditions is optically active or racemic is to be explained.
Concept introduction:
Hell-Volhard-Zelinski reaction takes place through the formation of an acid bromide enol intermediate. If the chiral carbon of the optically active carboxylic acid is involved in the enol formation chirality will be lost during enolization, as the double bonds are planar. Bromination of this enol can take place from either face of the enol double bond leading to the formation of a racemic mixture. If the chiral carbon does not take part in enol formation, then the resulting product will be optically active.
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Organic Chemistry
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- Organic ChemistryChemistryISBN:9781305580350Author:William H. Brown, Brent L. Iverson, Eric Anslyn, Christopher S. FootePublisher:Cengage Learning