Chemistry 234 Practice Exam 3. The Periodic Table

Transcription

1 ame: Last First MI Chemistry 234 Practice Exam 3 Instructions: The first 15 questions of this exam should be answered on the provided Scantron. You must use a pencil for filling in the Scantron sheet. Ensure all erasures are complete. Any questions left blank will be marked incorrect. Please write and bubble in your student ID number on the scantron. Answer the remaining questions on the exam itself. Show all work and provide complete explanations. The Periodic Table D T REMVE TIS EXAM CVER PAGE Page 1 of 8

2 Multiple Choice Choose the one best answer for each of the following questions. Bubble your answer in on the provided Scantron sheet. Additionally, circle your answer directly on the exam so that you can check your answers once the key is posted. (2 points each) 1. Will the following reaction occur as written? a. Yes, anhydrides can be converted into amides and carboxylic acids since the leaving group is a weaker base than C32. b. o, anhydrides cannot be converted into amides and carboxylic acids since the leaving group is a stronger base than C32. c. Yes, anhydrides can be converted into amides and carboxylic acids since the products have a greater amount of hydrogen-bonding. d. o, anhydrides cannot by converted into amides and carboxylic acids since the products are too polar. 2. If the ester shown below were saponified with a containing isotopicically labeled oxygen, what would the product be? (i.e. where does the from a end up in the product?) 1. a indicates isotopic label 2. + workup 3. Which substrate will give the indicated product at the fastest rate?? a c b d C 3 Cl a b c d e 4. Which one of the following hydrates is the least stable (i.e. which one is most likely to revert to the carbonyl species)? CF 3 a b c d e Page 2 of 8

3 5. Why are ketones less reactive than aldehydes? a. Ketones are more sterically hindered. b. Ketones are less electron deficient due to donation from the two alkyl groups. c. Ketones are more reactive. d. Ketones are more sterically hindered and ketones are less electron deficient due to donation from the two alkyl groups. 6. ow many hydrolyzable functional groups are present in the molecule shown below? a. Zero b. ne c. Two d. Three e. Four 7. Which arrow best describes the reaction shown below? 2 a b c d e 8. Select the correct IUPAC name for the following amine. a. Ethyl methyl propyl amine b. Diethyl, methylamine c. -ethyl--methyl-1-propamide d. -ethyl--methyl-1-propanamine 9. Which of the following is the direct product of the base-promoted hydrolysis ( - /2) of an ester? a. A nitrile b. A carboxylic acid c. An amide d. A carboxylate salt Page 3 of 8

4 10. Which one of the isomeric C39 amines would you expect to have the lowest boiling point? a. C3C2C22 b. C3C2C3 c. (C3)3 d. (C3)2C2 For questions 11-15, select the appropriate reagent from the reagent bank to accomplish each step in the synthetic sequence below. ote that some answers may require you to bubble in more than one letter. Record each answer on your Scranton sheet! 3 C Br 11 3 C C Cl Reagent Bank 1. DIBAL- -78 C C 3 MgBr LiAl a b c d ac C 3 PCC 2 C 3 e ab ac ad SCl 2 ab 4 C 3 ac 3 TsCl Pyridine ae bc bd be Page 4 of 8

5 Completion Section: Answer the remaining questions on the exam itself. Read the questions carefully and provide complete explanations. If you have multiple answers written, circle the answer that you want graded. 16. Provide the IUPAC name for each compound shown below. (3 points each) a) b) C Br c) C d) Br 17. Provide the missing structures in the synthetic scheme shown below. (2 points each) C 3 Ts 1) LA 2) 2 PBr 3 3 nitrile & acetal hydrolysis ac 18. Provide a representative name for each functional group or species shown below. (1 pt each) 3 P 19. Draw the hydrochloride salt of pseudoephedrine (shown below). (2 points) Page 5 of 8

6 20. Predict the major organic product for each reaction below. If the reaction does not proceed under the specified conditions, write o Reaction. ote: some questions have multiple steps associated with them. (2 points each) a. C 1. C 3 MgBr 2. + / 2 C 3 + b. Br 1. P 3 2. BuLi 3. 3-pentanone c. Cl ac 1. a 2 2. C 3 Br d. e C 3 I (xs) 2. Ag 2, 2 3. eat Trace + f. 1. K 2. Br 3. a, Show the complete electron pushing mechanism for the reaction shown below. (6 points) + 2 Page 6 of 8

7 22. Design a reasonable synthesis for the molecule below starting with propanal. You may use any necessary organic or inorganic reagents. (5 points)? 23. Given an unlimited supply of ethanol C3C2, show how it can be converted to the necessary molecules to perform a Wittig reaction to obtain 2-butene. Be sure to show all steps and reagents. Ethanol is your only source of carbon atoms. (6 points) 24. Predict the product and provide the complete electron pushing mechanism for the reaction shown below. (6 points) Et Cl Pyridine 25. Draw the hemiacetal and acetal formed by the reaction of butanal and 1-butanol. (2 points each) Page 7 of 8

8 emiacetal Acetal Page 8 of 8