Chapter 14.SE, Problem 36AP

Interpretation Introduction

Interpretation:

The structures of the two Diels-Alder adducts formed when isoprene (2-methyl-1, 3-butadiene) reacts with ethyl propenoate are to be given and why a mixture of products is formed is to be explained.

Concept introduction:

In Diels-Alder reaction, a dienophile reacts with a diene to yield a cyclic adduct. The reaction takes place through 1, 4 addition of the dienophile into the diene through a cyclic transition state. These reactions occur rapidly with dienophiles having electron withdrawing substituent groups in conjugation with the double bond and if the diene adapts a s-cis conformation during the reaction.

To give:

The structures of the two Diels-Alder adducts formed when isoprene (2-methyl-1, 3-butadiene) reacts with ethyl propenoate and to explain why a mixture of products is formed.