Interpretation:
When 2-methyl-2-propenal is treated with allyl magnesium chloride (H2C=CH-CH2-MgCl) in ether, then with dilute aqueous acid, a compound A is obtained, which, when heated strongly, yields an
Concept introduction:
Sigmatropic reaction can be described as the migration of allylic sigma bond at one end of the π-electron system to the other end of the π-electron system as an uncatalyzed intramolecular reaction. In some cases, Lewis acid catalysts can also be applied. Though, the position of π-bond is changed in Sigmatropic reaction, the total number of π-bonds remain unchanged. The sigma bond can be cleaved at the middle or at the end of the π-system. The formation of sigma bond at 3, 3-position of a 1, 5-diene is called as cope rearrangement. Notably, [3, 3] sigmatropic reaction of allyl vinyl ether is termed as Claisen rearrangement.
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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