Chem 140C Spring 2012 Practice Final Exam Answer Key

Transcription

1 Chem 140C Spring 2012 Practice Final Exam Answer Key Q1 (-- points) Q2 (-- points) Q3 (-- points) Q4 (-- points) Q5 (-- points) Q6 (-- points) Q7 (-- points) Q8 (-- points) Q9 (-- points) Q10 (-- points) Total (300 points) If you write the exam in pencil or erasable pen, you give up your right to any kind of regrade. Name PID#

2 1. Acidity (-- points). A. Circle the most acidic hydrogens (or hydrogens) in each molecule below and place them in order of their acidity with #1 being the most acidic and #4 being the least acidic. Work carefully. There will be no partial credit or regrades on this problem. Note: The acidic hydrogens may not be showing on the drawing. B. Circle the most acidic hydrogens (or hydrogens) in each molecule below and place them in order of their acidity with #1 being the most acidic and #4 being the least acidic. Work carefully. There will be no partial credit or regrades on this problem. Note: The acidic hydrogens may not be showing on the drawing.

3 2. Basicity (-- points) A. Place the following compounds in order of their basicity with #1 being the most basic and #4 being the least basic. Work carefully. There will be no partial credit or regrades on this problem. B. Place the following compounds in order of their basicity with #1 being the most basic and #4 being the least basic. Work carefully. There will be no partial credit or regrades on this problem.

4 3. Reactivity (-- points). A. Place the following molecules in order of their reactivity with methoxide ion. Label the most reactive as #1 and the least reactive as number 4. Work carefully. There will be no partial credit or regrades on this problem. B. Place the following molecules in order of their reactivity with CH 3 S - Na + via an S n Ar mechanism. Label the most reactive as #1 and the least reactive as #4. Work carefully. There will be no partial credit or regrades on this problem.

5 4. Chemical Reactions - Give the Product (-- points). Draw the organic products of the following reactions. Indicate stereochemistry where appropriate. A reasonable answer may be No Reaction.

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7 5. Chemical Reactions - Give the Reactant(s) (-- points). Draw the reactants of the following reactions. Indicate stereochemistry where appropriate.

8 6. Methodology (-- points). Show with equations three ways to make a secondary amine starting from a primary amine or a tertiary amine. Your 3 methods must use different reactions to either make the new C-N bond or break a C-N bond.

9 A. 7. Reaction Mechanisms (-- points, maximum). Draw reasonable mechanisms for the reactions below. Do 2 of 3 and clearly indicate which you want graded. Note that Part A is worth - points, Part B is worth -- points and Part C is worth -- points.

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11 8. Synthesis (-- points, maximum) Show how you would accomplish the following conversions. Do two of the three and clearly indicate which ones you want graded. Note that Part A is worth - points, part B is worth -- points and Part C is worth -- points.

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14 9. Challenge Problem (-- points, maximum) Do 1 of the following 2 problems. Clearly indicate which ones you would like graded. Note that Part A is worth -- points and Part B is worth -- points. A. Show how you would synthesize the dipeptide GlyGly starting from Gly and any other organic or inorganic reagents.

15 B. Show how you would synthesize the dipeptide GlyAlaPhe starting from Phe, Gly and Ala and any other organic or inorganic reagents.

16 10. Last Problem. (-- Points) At the end of each chapter we have studied a specialized topic dealing with an aspect of Industrial or Bio-Organic Chemistry. These topics are listed below. Choose one and use this page and the next page (front sides only) to tell us everything you know about this topic. You will either receive -, -, - or - points depending on how successfully you can convince the graders and me that you have a thorough and accurate understanding of at least what we went over in lecture or what is in the textbook on this topic. A. Fats and Fatty acids B. Carboxylic Acid Esters and the Energy Crisis C. Industrial Polymers D. Benzoquinone, Hydroquinones and Antioxidants E. Natural Products F. Thiazolium Salt Chemistry G. Nucleic Acids Lots of ways to approach this. The best advice is: Write down whatever you can to show the grader and me that you know what you are talking about. This will be judged on both quantity and quality.