Problems Set #3

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. In most cases only one of the two enantiomers is useful for a biological process. Explain briefly why.

2. In which of the following properties are enantiomers identical?

a. Melting point
b. Refractive index
c. IR spectrum
d. H-NMR spectrum in chiral solvent
e. optical rotation

3. Which factor(s) control(s) the asymmetric induction?

4. How can asymmetric induction be introduced to an achiral substrate?

5. Suggest a procedure to resolve a racemic mixture of 2-butanol.

6. Why is sodium hydroxide used in the formation of the alcohol (5)?

7. To test the purity of the alcohol (5), TLC is used. What do you expect to see if a mixture of hexane and dichloromethane is used as eluent?

8. Why is it important that you add the 30% hydrogen peroxide solution slowly to the cerium solution?