Problems Set (Meeting 10)

General Announcements

1. Make sure that you turn in a hardcopy of your research paper by November 7, 2008 at 5 pm and the electronic version to turnitin.com as well (CourseID: 2312446, Passwd: Chem30CL for Fall 2008). Late reports will be deducted points (10% per day including the weekend). If you do not submit the report online by Monday November 10, 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 October 28, 2008 at 11 am 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. No more exceptions!!!!

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 November 13 and November 14, 2008 in your regular lab section.

4. The final product of the lidocaine project has to be turned in to the TA by October 31, 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 diethylamine? 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. How is the product recovered after the previous step?

f. How is the crude product dried?

2. Carbonyl chemistry

a. Why does acetamide have a significantly higher boiling point than N,N-dimethylacetamide despite having a lower molecular weight?

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