last updated Tuesday, May 25, 2004

Meeting 16 (Acetyl Ferrocene)

The last quiz will be administered on Tuesday June 1, 2004 at 8 am. Please make sure to attend.

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

Homework assignments

1. What is the electrophile in this reaction? How is it generated in this reaction? Show an appropriate chemical equation.

2. Which organometallic compounds are present in the reaction mixture after the reaction? Draw their structures.

3. Flash chromatography is used in this experiment. First petroleum ether is used as eluent, later a mixture of petroleum ether with ~10% ethyl acetate. What do you expect to observe during this step of the purification? What would happen if the student decide to use pure ethyl acetate instead?

4. How do you explain the orange-red color of the ferrocene and acetyl ferrocene?

5. Student A has the task to purify diethyl ether. He askes his fellow student B and receives the following response:

"Oh well, since diethyl ether has a lower boiling point than water just perform a fractionated distillation. This should give you dry ether."

Not entirely sure, he asks his other neighbor about the same problem and hears from her:

" Well, ethers form peroxides. You might want to check for those first before you even try to purify your ether. After you removed them, you can reflux the peroxide free ether over some drying agent like sodium sulfate"

Comment on the two responses and then explain briefly how you would tackle the problem.