Problems Set - Meeting #7

1. What are the major advantages of a convergent synthesis route as compared to a linear route?

2. Referring to the reaction carried out in the lab, answer the following questions.

a. Why is 1,2-dimethoxyethane used in the reaction?

b. Which molecule is the dienophile in this reaction? How is it obtained?

c. What do yo observe during the reaction?

d. The final step is a recrystallization. Which problems is the student going to face there?

e. Many students observe a double melting point. How can this be explained?

3. A UV-Vis spectrum is also obtained for the compound obtained in this week's experiment.

a. Why does the procedure ask to use a quartz cuvette in this experiment?

b. What do you expect to change in the UV-Vis spectrum in comparison with last week's product?

c. Which concentration is needed for the UV-Vis characterization of the TPN?

4. The diene has to assume s-cis conformation in the Diels-Alder reaction. Explain briefly why.

5. Diels-Alder reactions are said to be stereospecific. Explain briefly and give an example.