CHEM 201 Final Exam (200 pts) Organic Chemistry ( I ) Spring - 2020 Name :-------------------------------Section : May 19, 2020 Dr. Hany F. Sobhi 550 / 551 ID # ---------------- Answer sheet is Page 1-Page 6, Print , Answer , Scan, and submit on Canvas Section # I ( 120 Pts): 1.____ 2.___ 7._ ___ 8. ____ 13. ____ 14.___ 15.____ 19._ ___ 20. ____ 21. ___ 25. ____ 26. ____ 27. ____ 31. ____ 32._ ___ 37._ ___ 38._ ___ CHEM 201 Spring 2020 3 .___ 9. ____ 33._ ___ 39._ ___ 4.____ 5. ____ 6.____ 10.____ 11.____ 12.____ 16.____ 22._ __ 17.____ 23. ___ 18._ ___ 24. ____ 28._ ___ 29. ____ 30.__ __ 34. ____ 35. ____ 36._ ___ 40._ ___ Dr. Hany F. Sobhi (Final Exam) Page 1 Section # 2 ( Q 1- Q 16 ) ( 80 points ) : 1 ) Draw the Fischer projection of (2R,4R)-2,4-dibromopentane. 2- Complete the following reaction? 3-Rank the following Functional groups according to their increasing oxidation level levels? 4- Provide proper IUPAC names for the compound below. CHEM 201 Spring 2020 Dr. Hany F. Sobhi (Final Exam) Page 2 5- Rank the following compounds in the order of increasing reactivity towards Bimolecular Nucleophilic Substitution Reactions SN2: 6- Draw the reaction mechanism of the SN2 of the conversion of S -2Bromobutane to R -2- Butanol ? f - Predict the products of each reaction below. Indicate radiochemistry and stereochemistry when relevant. 7. 8. CHEM 201 Spring 2020 Dr. Hany F. Sobhi (Final Exam) Page 3 9- 22 10- Provide structures for the reactants, intermediates, or products, as indicated, in the following reactions. Draw the structures in the boxes provided. 11. 12. CHEM 201 Spring 2020 Dr. Hany F. Sobhi (Final Exam) Page 4 13. - Predict the product of each reaction below. Be sure to indicate stereochemistry when appropriate 14. 15- Circle the least reactive compound in an SN1 reaction. 16 Indicate the catalyst : 16. _____ CHEM 201 Spring 2020 Dr. Hany F. Sobhi (Final Exam) Page 5 Section # 1 Multiple Choice ( Q 1- Q 40 ) ( 120 Pts ) Consider the pair of reactions below to answer the following question(s). a. or b. 1 The alkyl bromide starting materials in these reactions are classified as: a. b. c. d. 3° 2° 1° 4° 2. The solvent in these reactions is: a. b. c. d. nonpolar aprotic polar aprotic polar protic nonpolar protic 3. The nucleophile in these reactions is: a. b. c. d. K+ alkyl group Br− I− 4 .Which reaction is faster? 5. The mechanism for these reactions is: a. b. c. d. SN2 E2 SN1 E1 CHEM 201 Spring 2020 Dr. Hany F. Sobhi (Final Exam) Page 6 ----------------------------------------------------------------------6. Consider the two lines shown on the energy diagram below. In an SN2 reaction, a. the upper left line could represent Cl– and the lower left line I–. b. the upper left line could represent OH– and the lower left line CH3COO– . c. the upper left line could represent H2O and the lower left line H2S. d. the upper left line could represent (CH3)2NH and the lower left line (CH3)2N–. 7. Consider the two lines shown on the energy diagram below. In an SN2 reaction, these lines could compare the effect of which of the following solvents? a. CH3OH and CH3CH2OH b. CH3OH and H2O c. CH3OH and CH3CN CHEM 201 Spring 2020 d. DMSO and CH3CN Dr. Hany F. Sobhi (Final Exam) Page 7 8. Consider the two energy diagrams labeled A and B given below. A B Which of the following is correct with respect to these diagrams? a. A represents an SN2 reaction. b. B represents an SN1 reaction. c. B represents an SN2 reaction. d. A represents an SN1 reaction. e. both c and d To answer the following question(s), consider the reaction below: 9. The best reagents for accomplishing the above transformation are: a. 1. OsO4, pyridine 2. NaHSO3, H2O b. 1. Hg(OAc)2, H2O 2. NaBH4 c. 1. RCO3H, CH2Cl2 2. H3O+ d. 1. BH3, THF 2. H2O2, −OH 10. The alcohol product is classified as a: a. 1° alcohol b. 2° alcohol c. 3° alcohol d. 4° alcohol CHEM 201 Spring 2020 Dr. Hany F. Sobhi (Final Exam) Page 8 Label each transformation below as: a. b. c. an oxidation a reduction neither an oxidation nor a reduction Place the letter corresponding to the correct answer in the blank to the left of the transformation. 11. _____ 12. _____ 13. _____ 14. _____ ----------------------------------------------------------15. Which of the following pairs are not alternative reagents to prepare the indicated products? a. HCl, SOCl2 - preparation of b. HBr, NBS - preparation of alkyl bromides from alkenes alkyl chlorides from alcohols c. Br2 and HBr - preparation of d. diorganocopper reagents and organopalladium compounds - forming new carbon-to-carbon bonds alkyl bromides from alkanes CHEM 201 Spring 2020 Dr. Hany F. Sobhi (Final Exam) Page 9 16. Specify the hybridization on the carbons shown in the following structure. a. 1: sp3 2: sp2 b. 1: sp2 2: sp c. 1: sp3 2: sp d. 1: sp2 2: sp 17. Consider the following compound. This compound a. is weakly acidic. b. could produce a single carboxylic acid upon oxidation. c. would produce a high yield of product upon oxidative cleavage. d. yields an alkene upon treatment with hydrogen in the presence of a Lindlar catalyst. e. None of the above characterize this compound 18. What is the term given to the following species? a. carbene c. acetylide anion b. carbanion d. carbocation CHEM 201 Spring 2020 Dr. Hany F. Sobhi (Final Exam) Page 10 19. The following species a. formed when ethyne is treated with a strong base. b. is the conjugate base of acetylene. c. could react with bromoethane to form 1-butyne. d. could react with bromocyclopentane to form an internal alkyne. e. a, b, and c 20. An acetylide anion is more stable than either a vinylic or alkyl anion due to a. the stabilization of the negative charge in orbitals with higher s character. b. the greater distance of the negative charge from the nucleus of the carbon atom. c. the greater stability of an sp hybrid orbital. d. the larger number of π electrons. 21. What is the skeletal formula for the product of the reaction when the following is treated with BH3 in THF followed by H2O2? a. b. c. d. CHEM 201 Spring 2020 Dr. Hany F. Sobhi (Final Exam) Page 11 22. Which of the following alkynes will produce a single product upon mercury(II)-catalyzed hydration? a. 2-methyl-5-ethyl-3-heptyne b. 3,3-dimethyl-1-heptyne c. 3-hexyne d. 2-hexyne e. Both 3,3-dimethyl-1-heptyne and 3-hexyne 23. When the following substance is treated with excess HBr, The product of the reaction is a. b. c. d. A mixture of a and b would be produced. e. A mixture of a, b, and c would be produced. ---------------------------------------------------------------------- CHEM 201 Spring 2020 Dr. Hany F. Sobhi (Final Exam) Page 12 Consider the reaction below to answer the following question(s). Alkenes may be hydrated by the hydroboration/oxidation procedure shown. 24. The intermediate formed in the first step of this reaction is: a. b. c. d. 25. Hydroboration of alkenes is an example of: a. b. c. d. a rearrangement reaction. a substitution reaction. an elimination reaction. an addition reaction. 26. Hydroboration/oxidation of alkenes occurs with: a. b. c. d. anti stereochemistry. trans stereochemistry. syn stereochemistry. unpredictable stereochemistry. 27. The regiochemistry of hydroboration/oxidation of alkenes is: a. b. c. d. Markovnikov. non-Markovnikov subject to solvent effects. unrelated to alkene structure. CHEM 201 Spring 2020 Dr. Hany F. Sobhi (Final Exam) Page 13 -------------------------------------------------------------------------------------------------------------------28. Arrange the following bicyclic alkenes in order of increasing stability (least stable to most stable). a. b. c. d. III < II < I I < II < III I < III < II II < III < I 29. In which of the following groups can the carbon atom be a chiral center? a. b. c. d. e. The carbon atoms cannot be a chiral center in any of these groups. 30. Which of the following compounds will rotate the plane of polarized light? a. b. c. d. For the following question(s) MATCH each definition to a term from the list below. Place the letter of the term in the blank to the left of the definition. a. b. c. d. e. optically active chirality center chirality prochirality center enantiomers CHEM 201 Spring 2020 Dr. Hany F. Sobhi (Final Exam) Page 14 31. _____ describes an sp3-hybridized atom that can become a chirality center by changing one of its attached groups. 32. ____ describes organic molecules which rotate plane-polarized light. 33 - Consider this reaction when answering the following question(s): This reaction is an example of a. a substitution reaction. b. a rearrangement reaction. c. an addition reaction. d. an elimination reaction. 34. Which of the following could act as an electrophile? a. CN– c. NH3 b. NH2– d. H3O+ 35. Which of the following could act as a nucleophile? a. HCl c. BF3 b. CH3NH2 d. CH3Br 36 ) Select the structure of the major product formed from the following reaction. 1. Hg(OOCCH3)2 THF, H2O CH3 ? 2. NaBH4, NaOH CH3 CH3 CH2OH OH HO CH3 CH3 OH OH I a) I II b) II III c) III CHEM 201 Spring 2020 IV d) IV V e) V Dr. Hany F. Sobhi (Final Exam) Page 15 37) Select the potential energy diagram that best represents the following reaction: H+ OH H2O a) I b) II c) III d) IV e) V 38) 2-Methylpentan-3-ol is classified as . A) a primary alcohol B) a secondary alcohol C) a tertiary alcohol D) a phenol E) an enol 39) Which of the following best describes the geometry about the carbon-carbon double bond in the alkene below? A) E B) Z C) neither E nor Z CHEM 201 Spring 2020 Dr. Hany F. Sobhi (Final Exam) Page 16 40) Which of the following would be a reasonable synthesis of CH3CH2CH2CH2OH? a) 1-Butene 1-Butene b) 1-Butene c) 1-Butene d) H3O+, heat 1. BH3-THF 2. H2O2, NaOH 1. Hg(OAc)2, THF, H2O 2. NaBH4, NaOH 1. Ha(OAc)2/CH3OH 2. NaBH4, NaOH e) None of these choices. --------------------------------------------------------------------------------------------------------------------------- Have a Great Summer Dr. Hany Sobhi CHEM 201 Spring 2020 Dr. Hany F. Sobhi (Final Exam) Page 17
