Interpretation:
The products in the given cope rearrangements has to be predicted with stereochemistry.
Concept Introduction:
Cope-rearrangement:
It is a pericyclic reaction that involves the redistribution of six electrons through the formation of a cyclic transition state from which a
Example with mechanism of cope-arrangement:
In this mechanism, two pi-bonds and one sigma bond of the reactant molecule has been rearranged and formed two new pi-bonds through a cyclic transition state.
Identification of cope-rearrangement in a
In the cope-rearrangement, the flow of electrons takes place between six bonds that are bonded as
The carbon atoms that are involving in the cope-rearrangement are shown in bold.
Stereochemistry in a product formed:
- • In the product of a
chemical reaction , if a carbon atom has been attached with four different carbon atoms, then it is known as chiral carbon atom or stereocenter in the product. - • The bonds of the functional groups because of which a new chiral carbon is supposed to form have to be represented in solid wedge bond and hashed-wedge bonds according to the particular enantiomer.
- • Racemic mixture is the mixture of two enantiomers in equal proportions.
- • Enantiomers are non-superimposable mirror images.
- • Achiral product is the product in which there won’t be any chiral centre or stereocenter.
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Chapter 20 Solutions
Organic Chemistry
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- Organic ChemistryChemistryISBN:9781305580350Author:William H. Brown, Brent L. Iverson, Eric Anslyn, Christopher S. FootePublisher:Cengage Learning