Many of the in-chapter problems in Bruice seem aimed at mastering basic skills and knowledge, while end-of-chapter questions often require integrating several areas of knowledge. I try to work through the in-chapter questions while reading along with the text, and then work the end-of-chapter questions.
Question 76(a) from the end of chapter 17 is especially good for practice. The question states: "Cardura, a drug used to treat hypertension, is synthesized as shown below. (a) Identify the intermediate (A) and show the mechanism for its formation.
When confronted with questions like these, it makes sense to assume the catalyst will play an important role in the first step - in this case, by deprotonating one of the hydroxyl groups. This creates an activated alkoxide ion which can then execute a nucleophilic attack on a susceptible carbon.
The big question in this case is, "which carbon?" We have, for the most part, been attacking the carbonyl carbon. This occurs because the resonance structure of the carbonyl group draws elecrons away from the carbonyl carbon, creating a slightly positive electrophilic charge.
However, there's a trick in this question. We have to recognize when a carbonyl carbon might not be the primary electrophile. In this instance, the alpha carbon (or Carbon 2) is more susceptible to nucleophilic attack. The ester group draws electrons away from the alpha carbon, which is then attacked by the activated alkoxide ion.
After the addition of more base and a second deprotonation, the molecule then undergoes an intermolecular reaction. The second alkoxide ion attacks the beta carbon and the bromide leaves.
The final part of the reaction involves hydrolyzing the ester. The process here is shown in one step, but drawing out the full mechanism of the final step is excellent practice.
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