Announcements (make sure to read them since you will held responsible to it)

1. The first quiz will be administered in lecture on Thursday, October 9, 2014 at 11 am (covering the introduction to asymmetric synthesis and the resolution step). It is the student's responsibility to arrive on time which means that you have to be there at 10:55 am. In fairness to everybody else in the class, late arrivals (even if it is only one second) will not be allowed to take the quiz, which means that you will receive an automatic zero score for the quiz. If you do not place your name on the quiz to assume authorship, you will receive a zero score as well! You cannot add your name after time was called because this is considered cheating. It is also not allowed to start writing (including writing down your name on the quiz) until you are allowed to do so by the instructor. Failure to follow these rules will result in an immediate dismissal from the quiz resulting in a zero score. Bring a non-graphing calculator, ruler and pen/pencil (blue or black only, not green, red, pink, etc). Note that spelling errors on quizzes will be penalized with a 0.5 point deduction per incident (even if it is the same word mispelled several times).

2. The draft version of the paper will be due by Friday, October 17, 2014 at 4:30 pm in YH 3077E.

3. The instructor will not respond to anonymous emails. In other words, if you are not providing your real name (not just some alias!) with the email, you will not get a response. It would be also helpful to tell the instructor in which course you are enrolled and in which section or who your TA is if there are specifics that might have to be addressed in TA meetings. Questions of general nature should be posted on the course discussion board (www.piazza.com).

4. If you are not properly dressed in the lab (proper dresscode: long pants, closed-toes shoes, proper sized cotton lab coat, goggles protecting your eyes at all times and nitrile gloves, read UCLA PPE-policy), you will automatically be dismissed for the day the first time around resulting in a zero score for the lab meeting. The second time, you will be dismissed from the course due to safety concerns.

ATTN: The 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 the resolution of 1,2-diaminocyclohexane (step 1), answer the following questions.

a. Provide a balanced equation for this reaction including the proper stereochemistry for the product using the structures for organic compounds.

b. Why does a precipiate form during the initial stages of the addition of the diamine?

c. Why is glacial acetic acid added after the entire diamine was added?

d. A student isolates 3.20 g of the crude salt. How much water should the student use to recrystallize his crude?

e. After recrystallization and drying, he obtains 1.60 g of the salt. Determine the percentage yield for this reaction based on the available amount of the target enantiomer (assume that he used the quantities given in the reader) and comment on it. Show all calculations.

f. The optical purity of the tartrate salt is determined by GC/MS analysis. Outline a brief procedure for the sample preparation.

g. The next day, the student obtains his GC printout which shows three peaks: 5.9 min (20,000 units), 6.0 min (1,500,000 units) and 6.4 min (20,000 units). Assign the peaks and determine the optical purity of the sample. Show all calculations.

h. Assuming the GC analysis would be performed on a HP-5 column, how many peaks would the student observe? Explain briefly.

2. Referring to asymmetric synthesis, answer the following questions.

a. Why is asymmetric synthesis of great interest to chemists?

b. Briefly explain the difference between the "Cram rule" and the "Cram Chelate Model".

c. What will determine if a reaction displays a high or a low stereoselectivity?

d. In the 1980ties, Noyori introduced the reduction of aromatic ketones using BINAL-H. The reaction displays a high degree of enantioselectivity for R=n-Bu, but not in case of R=tert.-Bu. Rationalize this observation.

e. Why is a diphosphine like DIPAMP considered chiral while the corresponding diamine is not?