Problems Set #6

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. Why are trans alkenes usually poor substrates for epoxidation using the Jacobsen catalyst?

2. How can you explain that you do not obtain 100% of one enantiomer?

3. Why do you pass a slow air stream through your reaction mixture?

4. In the TLC part of your experiment, which compound to you expect to travel farther? Explain.

5. Referring to the structure of the Jacobsen catalyst, how can you describe the coordination figure around the Mn-atom?

6. Which changes do you expect to observe in the IR spectrum of the Mn-complex (in comparison with the ligand)?

7. How do you explain the dark-brown color of the Jacobsen catalyst?