Problems Set (Meeting 10)

General Announcements

1. Make sure that you turn in a hardcopy of your research paper by May 9, 2008 at 5 pm and the electronic version to turnitin.com as well (CourseID: 2266641, Passwd: Chem30CL for Spring 2008). Late reports will be deducted points (10% per day including the weekend). If you do not submit the report online by Monday May 12, 10 pm, you will receive a "zero" score for the paper. In addition, it will be reported to the Dean of Students. Any plagiarism, partial or full resubmission of a papers or/and other forms of cheating will result in a report to the Dean of Students as well. Make sure that you cite your sources and try to use your own words as much as possible. Here is a checklist what should be included into the report. If you have any questions, please contact your TA or instructor asap, and not an hour before the submission deadline.

2. The next quiz (=quiz 4) will be administered on May 1, 2008 at 12 pm and will cover steps 1 and 2 of the Lidocaine project. Make sure that you show up on time. Otherwise you will not be allowed to take the quiz.

3. The postlab report for the lidocaine project has to be written in the lab notebook and submitted to the teaching assistant. The due dates are May 13 and May 14, 2008 in your regular section.

4. The final product has to be turned in to the TA by May 7, 2008 at 5 pm for evaluation by the instructor. Late submission will not receive any credit. Make sure that you label the vial properly.

Questions

1. Referring to the conversion of a-chloro-2,6-dimethylacetanilide to licocaine (step 3), answer the following questions. Show pertinent chemical equations.

a. Why is it important that the a-chloro-2,6-dimethylacetanilide is as dry as possible for this reaction?

b. Why does the procedure asks for three equivalents of diethyl amine? What does this mean?

c. Why is the reaction carried out in toluene?

d. During the work-up, the reaction mixture is extracted with 3M hydrochloric acid. Which purpose does this extraction serve? In which layer is the product after the extraction?

e. At some point during the work-up, concentrated potassium hydroxide solution is added. Explain why and show the pertinent equation.

2. Carbonyl chemistry

a. Rank the following compounds in terms of their boiling points: acetamide, N-methylacetamide and N,N-dimethylacetamide Explain.

b. Acyl chlorides possess a significantly higher carbonyl stretching frequency then esters. Rationalize this observation.

c. What are the differences between a primary amine and a primary amide in the IR spectrum?