last updated Friday, February 11, 2005

Problem set  Meeting 12 

Announcement

The instructor will offer an in-lab demonstration of the setup on Monday February 14,2005 from 3-4 pm in YH6086.

Questions

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

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

3. Why is it important to mix the bromobenzene/diethyl ether solution slowly?

4. Why is it necessary to crush the Mg-turnings before placing them in the round-bottomed flask?

5. Outline a separation scheme for the isolation of benzoic acid starting at the point the Grignard solution was poured onto the dry ice. Show appropriate chemical equations.

6. Why are ethers most commonly used as solvents for Grignard reactions?

7. The description of phenyl Grignard using PhMgBr is strictly speaking not entirely correct. How can you prove this?