Problems Set (Meeting 9)

Announcements

1. The next quiz will be administered on Thursday May 4, 2006 at 12 am and will cover the entire Lidocaine project.

2. The final paper will be due on Friday May 12, 2006 at 5 pm in YH3077E.

3. You should finish the first two steps on the first day of the project.

Questions:

1. Referring to the conversion of 2,6-dimethylnitrobenzene to 2,6-dimethylaniline (step 1), answer the following questions.

a. Three equivalents of stannous chloride are used in the reaction. Explain briefly and show pertinent chemical equations.

b. The reaction has to carried out in a strongly acidic medium. Why is this necessary and how is this accomplished?

c. In the second part of the reaction, potassium hydroxide is used. Explain briefly and show pertinent chemical equations.

d. A student uses a large amount of sodium sulfate as drying agent. What would he observe?

e. Sketch the distillation setup. Which pieces are needed here?

2. Referring to the conversion of 2,6-dimethylaniline to a-Chloro-2,6-dimethylacetanilide (step 2), answer the following questions.

a. Why is it important to keep the a-chloroacetyl chloride bottle closed as much as possible? Explain briefly and show pertinent chemical equations.

b. What is the advantage of using the acyl chloride in the reaction?

c. What is used a solvent in this reaction? Rationalize this choice.Why is

d. Why is sodium acetate solution added to the reaction mixture?

e. How many signals are observed in the H-NMR and the C-NMR spectrum for the compound?