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.

Announcements

1. The first quiz will be administered on Tuesday January 16, 2007 at 12 pm covering step 2, step 3 and the theoretical aspects of asymmetric synthesis. Bring a ruler, non-graphing calculator and pen with you. Make sure to come on time.

2. The spectroscopy workshop will take place on Mondays from 5-6 pm in YH2200. The first workshop will be held on 1/22/2007.

Questions

1. Referring to the oxidation of the benzylic alcohol (step 3), answer the following questions:

a. What is the function of the dimethyl sulfoxide in this reaction?

b. How long is the reaction expected to take under normal circumstances? What does this mean logistically speaking?

c. How does the experimenter know if the reaction is completed?

d. Why is the solution poured into water after the reaction is completed?

e. Hexane used as solvent for extraction in this experiment. Explain.

f. The crude product is recrystallized from warm methanol. Rationalize this choice.

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

a. What is the basis for the separation of the different enantiomers?

b. Why should the diamine be added slowly to the tartaric acid solution?

c. Which purpose does the addition of the acetic acid serve?

d. What is the maximum yield (in g) based on the amounts given in the reader?

e. The accepted optical rotation value for the product of step 1 is a= +12.5^o. A student observes a specific optical rotation for his sample of a= +11.5^o (corrected for concentration). Rationalize the difference and explain which impact each of it has for the project overall.