Problem 14.28 Draw the product (A) of the following Diels-Alder reaction. A was a key intermediate in the synthesis of the addicting pain reliever morphine, the chapter-opening molecule. > + CH3O CH3O several A steps HO NC но morphine

17.18 Rank the following dienes in terms of reactivity in DielsAlder reactions (from least reactive to most reactive).

Ll.39.

Draw the product (A) of the following Diels–Alder reaction. A was a key intermediate in the synthesis of the addicting pain reliever morphine, the chapter-opening molecule.

Which compound would be the least likely to react as a diene in a Diels- Alder Reaction? A. B. C. D.

| Anthracene readily undergoes a Diels-Alder reaction with tetracyanoethene, even though anthracene is NC CN ? + aromatic. NC CN (a) Draw two possible products that can form from this reaction. (b) Explain why anthracene can readily undergo a Diels-Alder reaction, whereas benzene does not.

HBr 18.2 Give the product.

explain which reagents and why

6

Intramolecular Diels–Alder reactions are possible when a substrate contains both a 1,3-diene and a dienophile, as shown in the following general reaction.With this in mind, draw the product when each compound undergoes an intramolecular Diels–Alder reaction.