Concept explainers
Interpretation:
The two product in the given reaction are formed after [1, 7] sigmatropic rearrangement, one due to hydrogen migration and the other to deuterium migration. It should be represented the configuration of product by replacing the A and B with appropriate atoms (H or D)
Concept introduction:
In a sigmatropic reaction “ one new sigma-bond is formed as another breaks.”
Sigma tropic rearrangement reactions are designated with digits. For example a [1, 3] sigma tropic rearrangement describe a reaction in which the residue migrates from position 1 to position 3
Woodward –Hoffmann rules are the set of rules used to vindicate or predict certain aspects of the stereo chemical outcome and activation energy of pericyclic reactions.
Woodward – Hoffmann rules for sigma tropic rearrangement reactions are listed below
Migration of carbon and hydrogen will occur in a sigmatropic rearrangement reaction. Migration of hydrogen in suprafacial and antarafacial rearrangement can be represented as follows,
Carbon migrating with one lobe of its p orbital interacting
Carbon migrating with both lobe of its p orbital interacting
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ORGANIC CHEM ALC&STU S/G&S W/MASTER CHE
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- Organic ChemistryChemistryISBN:9781305580350Author:William H. Brown, Brent L. Iverson, Eric Anslyn, Christopher S. FootePublisher:Cengage Learning