Interpretation:
For each case, the formation of two enantiomers in the given reaction and the structural stereochemical relation between the enantiomers formed are to be determined.
Concept introduction:
A Diels Ander reaction is one between a conjugate diene and a reactant containing a double bond (dienophile) to form a product. The product is called adduct.
Diels Ander reactions are highly stereospecific. The configuration of the dienophile is retained in the product, and the reaction is a syn addition reaction.
The dienes react with dienophiles in cis forms rather than trans forms.
Endo and exo refer to the orientation of the dienophile and its electron-withdrawing group when it reacts with a diene in a Diels Ander reaction.
Endo is favored in the transition state of aDiels Ander reaction because it has a lower energy.
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Organic Chemistry
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