last updated Tuesday, February 17, 2004

Problem set  Meeting 12 (2-19-2004)


1. For the Grignard reaction, water should be excluded as much as possible. How is this  accomplished in this reaction?

2. How can you initiate the reaction? How do you know that the reaction started?

3. How can you minimize the formation of biphenyl in the reaction?

4. Why is sulfuric acid added during the work-up of the reaction? Show appropriate chemical equations.

5. During the Grignard work-up, aqueous sodium hydroxide is used. Why? Can it be replaced by sodium bicarbonate solution? Show appropriate chemical equations.

6. Why are ethers used as solvents for many Grignard reagents?

7. Why are alkyl bromides more often used as starting materials for the formation of Grignard reagents than chlorides or iodides?

8. Why are the following functional groups incompatible with most Grignard reagents? Show appropriate chemical equations.

a. secondary amine

b. thiol

c. nitrile