CHEMISTRY 3331: Fundamentals of Organic Chemistry I Final Exam. Prof. Ognjen Š. Miljanić. Last 4 Digits of Student ID Number:

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1 CHEMISTRY 3331: Fundamentals of Organic Chemistry I Final Exam Prof. Ognjen Š. Miljanić December 7, 2011 Name: (print legibly) Last First Last 4 Digits of Student ID Number: Read all directions very carefully. Write your answer legibly in the designated spaces and think about what you are doing. Give only one answer for each question. Total number of points is (40 points) This question has several parts. In each, circle only one compound. Circle the weakest acid: Circle the weakest bond: Circle the most stable cation: Circle the only diene: DO NOT WRITE IN THIS SPACE F I N A L S C O R E 1 D O N O T

2 2. (120 points) For each of the following reactions or series of reactions, draw the structure of the major product(s) in the box. Be sure to clearly indicate stereochemistry where this is pertinent. If you think that no reaction occurs, write "No Reaction". 2 D O N O T

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5 2. (60 points) Give detailed mechanisms which explain the two reactions presented below. Show all charges and intermediates, and use curved arrows to indicate the flow of electrons. Do not draw transition states. 5 D O N O T

6 3. (50 points) For each of the following structures, give a complete systematic IUPAC name. Indicate the stereochemistry where needed. 6 D O N O T

7 4. (50 points) For the two conversions given below, outline a series of synthetic steps which would efficiently accomplish the conversion. You may use any organic compound with two or less carbons, and any inorganic reagent. Give a step-by-step outline and do not give mechanisms. 7 D O N O T

8 5. (20 points) Draw the structure of 2,3-difluorobutane. Now, consider the C2 C3 bond in 2,3-difluorobutane and draw all three staggered conformations for this molecule. Circle the least stable conformation 8 D O N O T

9 7. (40 points) Molecule A has a mass spectrum characterized by dual molecular ion. The two ions are in 1:1 ratio and weigh 164 and 166 mass units. The 1 H NMR spectrum of this compouns shows three peaks: a singlet at 0.94 (integrates for 9H), a doublet at 1.79 (integrating for 3H), and a septet at 3.58 (integrating for 1H). Its 13 C NMR spectrum contains four peaks, at 21.5, 25.7, 40.0, and Treatment of compound A with potassium t-butoxide produces compound B, which has molecular formula only a single molecular ion at 84 mass units, and a diagnostic medium-strength IR absorption at 1660 cm 1. Compound B has four peaks in its 1 H NMR spectrum: a single at 1.20 (integrates for 9H), and thre double doublets at 5.02, 5.07, and 5.70, which all integrate for 1H each. Its 13 C NMR spectrum has four peaks, now at 29.5, 33.7, 106.7, and Based on this information, draw the structures of compounds A and B in the provided boxes, and show your reasoning. 9 D O N O T

10 8. (10 points) Enols are normally less stable than their corresponding ketones. In the example below, this trend is inverted. Explain why. 9. (20 points) Assign (S) or (R) designators to all stereocenters in the molecule of glucose shown below: 10 D O N O T

11 10. (BONUS CREDIT: 20 points) Formulate your own question related to nuclear magnetic resonance spectroscopy and answer it. 11 D O N O T

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14 NOTHING WRITTEN ON THIS PAGE WILL BE GRADED 14 D O N O T