ON THE FIRST DAY OF CHRISTMAS DR. RUSSELL GAVE TO ME, ORGANIC CHEMISTRY... Thanks to Dr R for the title!

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1 N TE FIRST DAY F RISTMAS DR. RUSSELL GAVE T ME, RGANI EMISTRY... Thanks to Dr R for the title! rganic hemistry E 310, Final Exam 150 cautiously optimistic points! December 11, 2017 Note: This exam totals to 196 points. Your score will be calculated by multiplying your total points out of 196 times (150/196), rounding to the next higher whole number and then adding any extra credit points. Rules of the road: 1. There are 12 questions on 7 pages, plus two extra credit questions for your amusement. 2. No electronic devices of any kind. This includes, but is not limited to the following: PDAs, cell phones, pagers, calculators, mp3 players and multifunctional watches. Students found with these devises at their desk or on their person will fail the exam and be reported to the Dean of Students. 3. No, I am not kidding! 4. This exam is for the sole use of the student whose name appears below. This exam may not be reproduced in any form without written consent of the instructor. 5. Read the agreement and sign below before you begin. 5. Good skill! K.. Russell I have read and agree to follow the above rules. Furthermore, I hereby recognize that I am subject to and agree to abide by the onor ode, which provides standards that encourage ethical academic behavior and imposes penalties for violations of such standards. Printed Name : Signature :

2 Final Exam: n the first day of hristmas E seltamivir (below) is a second-generation oral neuramidinase inhibitor, widely used for the treatment and prevention of influenza A and B viral infections, including avian flu. Assign the absolute configuration (R, S, E, Z) to the indicated sites in seltamivir. (12 points) Answers a b c d 2 N a c b d N 2 2. Identify the compound (or compounds) that has (have) the properties described below. (14 points) A 3 a. is chiral: b. is meso: B D E c. as at least one diastereomer: d. as three different peaks in the 1 NMR spectrum and has two different peaks in the 13 spectrum: e. as four different peaks in the 13 NMR spectrum: 3. Rank the carbocations below in order of increasing stability. (12 pts) A B D Least stable < < < Most stable 1

3 Final Exam: n the first day of hristmas E Provide the major product(s) for the reactions below. learly indicate the stereochemistry in your structures where appropriate. Where more than one stereoisomer is formed you only need to draw one of the stereoisomeric products. ther stereoisomers should be indicated by writing, + enantiomer or + diastereomer, as appropriate. heck the boxes on the right to indicate whether the reaction product solution would be optically active ([a] D 0) or not optically active ([a] D = 0). (30 points; product(s) = 4, stereochem = 2) 3 a) + heat b) 1. B , K c) 1 mol Br 2 2 l 2 d) BF 3 + e) l 2 hν 2

4 Final Exam: n the first day of hristmas E For each pair of molecules below fill in the blank with their relationship. hoices are identical, conformational isomers, constitutional isomers, enantiomers, diastereomers, resonance contributors and non-isomeric. (9 points) Rank the bases below in order of decreasing basicity. (12 pts) l 3 2 N 3 A B D Most basic > > > Least basic 7. Determine the structures for compounds X and Y that fit the description below (8 points) ompounds X and Y has the formula Both X and Y react with one molar equivalent of hydrogen in the presence of a palladium catalyst to form 2-methylhexane. The heat of hydrogenation of X is greater than that of Y. Both X and Y react with l to give the same single 7 15 l compound as the major product. Structure of X Structure of Y 3

5 Final Exam: n the first day of hristmas E For each pair below: (36 points) a. ircle the molecule that best fits the description on the right. If both molecules fit the description equally circle them both and write, same. If neither fits, write neither. (3 points) b. Provide a brief explanation regarding the fundamental physical property behind the trait. Typically one sentence will do. (3 points) a) vs. has more resonance contributors of equal or greater stability 3 3 b) N vs. N Atom where proton ( + ) would add 3 3 c) vs. Less reactive in a Diels-Alder reaction 3 d) vs Greater % of more stable conformation e) vs. 3 3 molecule with a larger dipole moment f) 3 vs. 3 more deshielded carbon in a 13 spectum 4

6 Final Exam: n the first day of hristmas E Give the complete mechanism for the reaction(s) below (24 points) For full credit your mechanisms must include the following: Proper arrows to show all electron motion. a. 2 S 4 2 b. Br Your mechanism must show how both products are formed 5

7 Final Exam: n the first day of hristmas E onsider the reaction below. (12 points) a. Provide the electron pushing mechanism that shows how both products are formed. b. Use the energy diagram on the right to label each structure in your mechanism (A-G), including the given starting materials and products. Transition states can be indicated by writing the appropriate letter over the arrow where the transition state would exist. c. Br Br + Br A B Energy E D F G Reaction oordinate 11. omplete the synthesis below. I will give you the structure of but-1-yne for 2 points. Show all reagents and conditions necessary for each step. Show all synthetic intermediates (any molecule that you would isolate, no R groups). Note: Do not show mechanisms. (12 points) step(s) But-1-yne + one diastereomer 3 6

8 Final Exam: n the first day of hristmas E The compound with formula gave the 13 - and 1 -NMR spectra below (15 pts) a. alculate the degree of unsaturation for this compound. b. Propose a structure that is consistent with the provided spectroscopic data PPM PPM DU = Your final structure goes in the box. It is what I will grade. If there is more than one structure the problem will not be graded. Extra redit. 1 Barry Sharpless won the 2001 Noble prize in chemistry largely for the chemical reaction the bears his name. What functional group is involved with this reaction? 2. What was your favorite topic in organic chemistry? (3 points) 7