Concept explainers
Interpretation:
In the Diels-Alder reaction, which interaction out of A and B leads to form the major product is to be explained.
Concept introduction:
Diels-Alder reactions are concerted and stereospecific. When the diene and the dienophile of a Diels–Alder reaction are both unsymmetric, the major isomeric product is the one produced by the approach that exhibits the more favorable electrostatic attraction among atoms undergoing bond formation. The oppositely charged species are attracted by each other, while there is a repulsive interaction between the same charged species. Therefore, the regiochemistry in Diels-Alder reaction depends on the nature of substituents on diene as well as that on dienophile. An electron-donating substituent on the diene and an electron-withdrawing substituent on the dienophile not only enhance the rate of given Diels-Alder reaction but also decide which isomer will form predominantly and the stereochemistry as well.
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- Based on the given information, determine the diene and dienophile of the Diels-Alder reaction.arrow_forwardWhat combination of diene and dienophile undergoes Diels-Alder reaction to give adduct?arrow_forwardAlthough the Diels–Alder reaction generally occurs between an electronrich diene and an electron-deficient dienophile, it is also possible to have inverse-demand Diels–Alder reactions between suitable electrondeficient conjugated double bonds and electron-rich alkenes. These reactions are particularly useful because they allow for the incorporation of heteroatoms into the new six-membered ring. Predict the products of each inverse-demand Diels–Alder reaction below. Be sure your products reflect the correct stereochemistry. If more than one regioisomer is possible, draw both.arrow_forward
- This is a Diels-Alder reaction between furan + maleic anhydride (endo and exo products). For each cycloaddition product, draw in all hydrogen atoms, and write the molecular formula below.arrow_forwardWhich of the following compounds can arise directly from a Diels-Alder reaction? Please circle any structures that can, and then identify the appropriate diene(s) and dienophile(s) that would lead to that compound. Be sure to pay attention to E-IZ- stereochemistry in all of the reactants. For those that cannot undergo a Diels-Alder reaction, please explain why. OEt o CN .cO,Me Meo OMe H (+-) (+/-) (+/-) (+/-)arrow_forwardWhich of the following compounds can arise directly from a Diels-Alder reaction? Circle any structures that can. Then, identify the appropriate diene(s) and dienophile(s) that would lead to the compound. Pay attention to E-/Z- stereochemistry in all of the reactants. For those that cannot undergo a Diels-Alder reaction, please explain why.arrow_forward
- Which diene could not participate in a Diels-Alder reaction?arrow_forwardGiven the diene and dienophile shown, identify the carbon atoms that will become new stereocenters in the Diels-Alder product.arrow_forwardDraw the conjugated diene and dienophile which can be reacted to give the Diels-Alder adduct shown belowarrow_forward
- A Diels-Alder reaction that shows the stereospecificity of the reaction with respect to the dienophile onlyarrow_forwardThe below reaction is a retro Diels-Alder reactions. Is is the reverse process of a Diels-Alder reaction with the formation of a diene and dienophile from some cyclohexene. It can be accomplished spontaneously with heat. Determine the product of the reaction. 4 Heatarrow_forwardWhy does the diene need to be in the s-cis conformation to yield the cyclic product?arrow_forward