last updated Thursday, February 19, 2009

Meeting 15 (Acetyl Ferrocene)

Important Announcements:

1. The proposal is due on February 27, 2009 at 5 pm in YH 3077 E (If you have problems please see me asap!). Late proposal will not be accepted and will lead to an automatic "F"-grade for the course. The important references have to be attached to the proposal. The proposal has to be submitted to turnitin.com as well (same course ID as before) by 11 pm on February 27, 2009 only one per group! Make sure that you have an electronic copy of your proposal with you.

2. The next quiz (=quiz 6) will be administered on February 25, 2009 at 8 am. It will cover the esterification and nitration reaction. Make sure that you show up on time, which means that you have to be seated by 7:55 am. Otherwise you will not be allowed to take the quiz.

3. In the lab, you will only carry out the acylation of ferrocene, but not the synthesis of ferrocene. This part will be done individually and not in groups.

4. 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 March 3 or March 4, 2009 in your regular lab section.

Homework assignments (due February 24/25, 2009)

1. Referring to the synthesis of acetyl ferrocene, answer the following questions.

a. How is the electrophile generated in the lab? Show pertinent chemical equation(s).

b. Provide two other methods on how to obtain the the electrophile used in the lab.

c. What is the solvent in this reaction?

d. Why is it important to "neutralize" the organic layer before performing the column chromatography step? Which pH-value is the student looking for here?

e. Sketch a TLC plate (SiO₂, petroleum ether:ethyl acetate=19:1) that shows ferrocene in lane 1, acetyl ferrocene in lane 2 and diacetyl ferrocene in lane 3. What does this means in terms elution of the compounds off the column?

f. In many cases, the student observes a dark blue or dark green color at some point during the work-up. Rationalize this observation.

g. The ¹³C-NMR spectrum of acetyl ferrocene exhibits four signals at from d = 68-80 ppm. Rationalize this observation.