Which of the following would be the most reactive diene in a Diels-Alder reaction?
D) These are equally reactive.
E) None of these undergo Diels-Alder reactions.

Question

Which of the following would be the most reactive diene in a Diels-Alder reaction?
D) These are equally reactive. 
E) None of these undergo Diels-Alder reactions.

Quizplus · Accepted Answer

The most reactive diene in a Diels-Alder reaction is typically the one with the least amount of electron density on the diene system. In option B, there are two electron-withdrawing groups (a carbonyl and a cyano group) attached to the diene, which makes it the most electron-poor and therefore the most reactive diene in the group. Options A and C both have only one electron-withdrawing group attached to the diene, and are therefore less reactive.

Which of the Following Would Be the Most Reactive Diene