Week 8 Problem Set 30BL

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

1. What is function of the sulfuric acid in this experiment? Show pertinent equations if necessary.

2. When preparing a Grignard reagent, why is it necessary to avoid the presence of water?

3. You will obtain a TLC spectrum for your purified and crude product. The following solvents will be provided: methanol, dichloromethane, toluene and hexane. Which of these solvents would be best suitable for the task?

4. Why does the procedure you not to place the solution in an ice-bath?

5. Predict the products for the following reactions. Include the approximate ratio if more than one product obtained and the correct stereochemistry.

6. How many signals do you expect to observe in the ¹H-NMR spectra of the following compounds? In which of the following ranges do those signals show up: 0-5 ppm, 5-6.5 ppm, 6.5-9 ppm, 9-15 ppm huh?

Note:

The last spectroscopy work-shop will be held on Monday, May, 19 at 6 pm in YH2200. The work-shop will discuss H-NMR and combined problems. Please make sure to get the handouts from the web site before attending to the work-shop.