ATTN: answers to the below questions are due at the start of your second lab period; these answers should be part of your pre-lab write-up.

1. Referring to step 3, answer the following questions:

a. The temperature of the reaction shoudl not exceed 115 ^oC. Explain briefly why.

b. The crude product is recrystallized from hot methanol. Rationalize this choice.

c. The C=O stretching frequency for the aldehyde is located at 1650 cm^-1. Explain briefly.

d. Which parameters determine the rate of the reaction here?

2. Referring to the resolution (step 1), answer the following questions.

a. Why is L-(+)-tartaric acid used in this step?

b. What is the theoretical yield (in 30% and g) for the ammonium salt that you are planning to isolate? Show calculations.

c. Why is glacial acetic acid added in this reaction?

d. Assuming you isolated 10 g of the crude product, how much water whould be used to recrystallize the crude?

3. How can enantiomers be separated using column chromatography?

4. Many biochemical processes yield compounds in high enantiomeric access. Lipase is able to hydrolyze one enantiomer of an ester, but not the other one. How would you isolate the resulting enantiomeric acid from the unreacted ester?