last updated Thursday, May 20, 2004

Meeting 15 (Ferrocene)

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

Important Announcements:

1. Proposal: due on May 28, 2004 at 5 pm in YH1217 (If you have problems please see me asap!)

2. Oral Presentation: time and location to be assigned (group presentation, but everybody has to speak!)

Homework assignments

1. Ferrocene is very stable, while cobaltocene is very air sensitive. Rationalize the differences in reactivity of the two metallocenes.

2. Most metals form different cyclopentadienyl complexes. Based on its structure, explain why potassium cyclopentadienide (KCp) dissolves very well in THF, but not well in hexane.

3. Cyclopentadiene is not commercially available.

a. How is it obtained in the lab?

b. Which precautions have to be taken when obtaining the monomer?

4. Referring to the following reaction, answer the following questions

Co(NH₃)₆Cl₂ + 2 NaCp ----> CoCp₂ + 2 NaCl + 6 NH₃

a. Suggest two good solvents for this reaction. Rationalize your choice.

b. What are the driving forces for the reaction?

c. Which color does the product have?

5. What are the cyclopentadiene complexes of titanium used for?