1. General

Make sure that you keep writing on your formal report. See your teaching assistant or instructor if you have questions about the format. The draft version is due on October 28, 2005 at 5 pm.

Review the following topics: ¹H-NMR and ¹³C-NMR spectroscopy, GC/MS

2. Experiment (Jacobsen Catalyst)

If you do not have 1.0 g of the Jacobsen ligand, downscale the other reagents accordingly.

It is advisable to crush up the Mn(OAc)^₂ a little bit in order to speed up the reaction.

The round bottom flask used should not be more than half full. Why?

Make sure that the air stream and the temperature of the hotplate is not too high during the oxidation reaction . If the solvent level lowers too much, the reaction will not take place anymore. Keep the solvent level around 20 mL in the flask (by adding more solvent if necessary).

The reaction has to be monitored by TLC in order to determine when it is completed. How do you know that?

The removal of the dichloromethane should be done at low heat using an air stream. However, the evaporation should be done slowly. Why?

3. Things to think about

a. Why do you have to reflux the ligand initially with 25 mL of ethanol?

b. Which solvent mixture is used in this experiment for TLC?

c. Why is a mixture of dichloromethane and heptane used in the procedure and not dichloromethane and pentane?