Announcements

1. The first quiz will be administered on Tuesday, October 6, 2009 at 11:00 am covering the resolution, polarimetry and introduction to asymmetric synthesis. Bring a ruler, non-graphing calculator and blue or black pen with you. Please make sure that you arrive on time (this means that you should be seated by 10:55 am!!!). Late arrivals will not be allowed into the class room since they disturb the rest of the class!! This also means that you will not be allowed to take the quiz!!!

2. The question below are due in your prelab for October 6 and 7, 2009 (=meeting 4).

3. Starting this week, students will only be allowed to attend their own lab section. This means that you have to be better prepared when you come to the lab to get the work done in the allotted time, which is easily possible if you know what you understand what you are doing. If there are questions, you should ask them during office hours!

ATTN: Answers to the below questions are due at the start of your lab period; these answers should be part of your pre-lab write-up.

1. Referring to the synthesis and characterization of the Jacobsen catalyst, answer the following questions.

a. The ligand is refluxed in 95% ethanol in the beginning. Explain briefly why.

b. The procedure recommends to crush the manganese(II) acetate prior to the addition to the ligand suspension. Explain briefly why.

c. Mn(OAc)₂*4 H₂O is light pink in color. Rationalize this observation.

d. What is used as oxidant in this reaction? How is it introduced to the reaction?

e. The reaction is monitored with TLC. Assuming the reaction is incomplete, sketch the TLC plate. What is the student looking for here?

f. After the removal of the drying agent from the organic layer, heptane is added and the mixture is gently heated. What is supposed to happen at this point? How does the student know that he is done heating?

g. What are the characteristic peaks for the catalyst in the FTIR spectrum?

h. The catalyst is also characterized using UV-Vis spectroscopy. Which solvent should be used here? What is the proper concentration(s) for the measurements assuming that the student wants to record all peaks found in the literature?