Organic Chemistry II KEY March 27, Which of the following reaction intermediates will form the fastest in the reaction below?

Transcription

1 rganic Chemistry II KEY March 27, 2013 Exam 2: VERSI D 1. Which of the following reaction intermediates will form the fastest in the reaction below? C 1 equiv a 2 a) IV b) III c) II d) II & III e) I I. II. 2. ow many π electrons are associated with the aromatic system of the compound below? D a) 12 b) 10 c) 8 d) 6 e) 2 1

2 rganic Chemistry II KEY March 27, 2013 Exam 2: VERSI D 3. The reaction intermediate(s) that gives rise to the major kinetic product(s) in the reaction of 1 benzyl 3 phenyl 1,3 cyclopentadiene with one equivalent of Cl is (are): B (Assume no rearrangements) I. II. a) I, II & IV b) I & II c) II & III d) III e) I 4. Rank the dienophiles from most reactive to least reactive in the Diels Alder reaction (most>least) B I II III IV a) I > II > III > IV b) III > II > I > IV c) III > I > II > IV d) II > III > I > IV e) I = II > III > IV 5. Which nitrogen atoms of the compound below has the lowest pka? A II III IV a) IV b) II & IV c) III d) I e) II, III & IV 2 I 2

3 rganic Chemistry II KEY March 27, 2013 Exam 2: VERSI D 6. In which of the following solvents will the reaction outlined below occur the fastest? A Cl 2 a) 10% Ethanol in water b) 25% Ethanol in water c) 40% Ethanol in water d) 35% acetone in water e) 25% acetone in water 7. Which of the following starting materials will provide the product below in a Diels Alder reaction? B C 3 I. II. 3 C 2 3 C 2 C C 3 C a) IV b) I c) I & II d) I & III e) II 3 C + 2 C 3 3 C C 8. Rank the substituted anilines from strongest base to weakest base (strongest > weakest). D I 3 C 2 II C 3 2 C 3 III C 3 2 a) III > VI > II > V > I > IV b) III > I > VI > V > II > IV c) I > III > II > VI > V > IV d) III > II > VI > I > V > IV e) I > II > III >V I > V > IV 2 3 C C 3 IV 2 V VI C 3 3

4 rganic Chemistry II KEY March 27, 2013 Exam 2: VERSI D 9. Which of the following structures represents 4 benzyl 1 cyclohexyl 2 phenylbenzene? E a) b) e) c) d) 10. Which of the following dienes cannot undergo Diels Alder reaction? E I II III IV V a) I & III b) II & IV c) III & V d) I, IV & V e) I, III & V 11. Which of the following structural modifications would increase the rate of the reaction of isbogrel with 3 +? C Isbogrel a) introducing a methyl group at C 12 b) introducing a nitro group at C 11 c) introducing a methoxy group at C 9 d) introducing an acetyl group at C 7 e) a & c 4

5 rganic Chemistry II KEY March 27, 2013 Exam 2: VERSI D 12. Which of the following atoms labeled in the compound below has the lowest pka? B a b c d a) d b) c c) b d) a e) a & c 13. Which of the following reactions corresponds to the reaction energy diagram below? A I. C 3 3 C Br IS II. C 3 Energy Br SM 3 C C 3 Reaction rogress C 3 Br a) III b) I & III c) II & III d) I & II e) IV Br 14. The major kinetic product(s) of the reaction below: B 1 equivalent Br 2, 2 (kinetic conditions) a) is a single stereoisomer b) are a mixture of diastereomers c) are a mixture of positional isomers d) is a racemic mixture e) contains a conjugated diene 5

6 rganic Chemistry II KEY March 27, 2013 Exam 2: VERSI D 15. Which of the following reaction energy diagrams corresponds to the reaction given below? A Cl a) b) Energy Energy SM SM Reaction rogress c) d) Energy Energy Reaction rogress SM SM e) none of these Reaction rogress Reaction rogress 16. What is the net sigma value effect on the ionization of the sulfonamide functional group of bumetanide? A 2 S a) b) c) d) e) 0.38 Bumetanide 6

7 rganic Chemistry II KEY March 27, 2013 Exam 2: VERSI D 17. Which of the following compounds is aromatic? D I. II. a) IV b) III c) II d) I e) I & IV 18. Rank the relative rate of reaction of each of the compounds below with 1 equivalent of 3 + from fastest to slowest (fastest> slowest). B I. II. a) IV > I > II = III b) I = IV > III > II c) IV > I > III > II d) IV > III > II > I e) IV > III > I > II 19. Which of the following statements is true regarding the structure of acebutolol (an antihypertensive agent)? C 3 C Acebutolol a) Acebutolol is meta substituted b) The substituent at C 1 is an acetoxy group. c) The substituent at C 3 is an electron donating group by resonance d) Acebutolol can undergo base catalyzed hydrolysis with a, 2 to give an alcohol and benzoic acid product. e) b & c 7

8 rganic Chemistry II KEY March 27, 2013 Exam 2: VERSI D 20. Rank the following compounds from strongest base to weakest base (strongest> weakest). A I. II. a) II > III > I > IV b) IV > I > III > II c) IV > II > I > III d) II > III > I = IV e) II > III > IV > I 21. The major product(s) in the Diels Alder reaction below is (are): D Br + 3 C a) I b) II & IV c) II d) II & III e) IV I. II. Br Br 3 C 3 C 3 C Br 3 C Br 8

9 rganic Chemistry II KEY March 27, 2013 Exam 2: VERSI D 22. Eugenol is a phenolic compound that could be used in a Williamson ether synthesis, much like guaiacol is used to prepare guaifenisin. Reaction of eugenol with 3 chloro 1,2 propanediol in the presence of a provides a product with a molecular weight of g/mol. The proton MR spectrum of eugenol is provided below. Which of the following structures represents eugenol? D I. II. V. C 3 C 3 C 3 a) V b) IV c) III d) II e) I C 3 9

10 rganic Chemistry II KEY March 27, 2013 Exam 2: VERSI D 23. (A) resonance form(s) of the compound below is (are): D I. II. a) I & II b) III c) IV & V d) III & V e) V V. 24. A conjugate acid of carbuterol is: B 2 Carbuterol a) I b) II c) II & III d) I & IV e) IV I. II

11 rganic Chemistry II KEY March 27, 2013 Exam 2: VERSI D 25. Which of the following compounds below contains a ortho substituted benzene ring? E I. II. Raloxifene Cl Losartan F S a) I & II b) I, III & IV c) II & III d) IV e) I & IV C 2 3 C Cervastatin ropafenone 11

12 rganic Chemistry II KEY March 27, 2013 Exam 2: VERSI D Substituent Abbreviation meta para acetamido Ac acetoxy Ac acetyl Ac alkenyl C 2 =C amino bromo Br tert butyl (C 3 ) 3 C chloro Cl cyano C ethoxy Et ethyl Et fluoro F hydrogen hydroxy methoxy Me methyl Me nitro phenoxy h phenyl h trifluoromethyl F 3 C trimethylamino (C 3 ) Table 1: values for Various Substituents 12

13 rganic Chemistry II KEY March 27, 2013 Exam 2: VERSI D Range Kind of roton ppm atoms bonded to sp3 carbons where the sp3 carbons are only bonded to other sp3 carbons and hydrogen (alkanes) ppm atoms bonded to sp3 carbons where the sp3 carbon is bonded to at least one sp2 carbon and no heteroatoms (allylic, benzylic,alpha ) ppm atoms bonded to an sp3 carbon that is also bonded to at least one heteroatom ppm atoms bonded to sp2 carbons of alkenes (not aromatic sp2 carbons) ppm atoms bonded to sp2 carbons of an aromatic ring ppm atom bonded to an sp2 carbon atom of the carbonyl group of an aldehyde or atom bonded to the sp3 oxygen of a carboxylic acid. Anywhere atom directly bonded to a heteroatom other than the oxygen atom of a carboxylic acid. Show up as a broad singlet (eg. of alcohol or phenol; of amine or amide) Chemical Shift Ranges of Various roton Types in roton MR Spectroscopy 13

14 rganic Chemistry II KEY March 27, 2013 Exam 2: VERSI D 14

15 rganic Chemistry II KEY March 27, 2013 Exam 2: VERSI D 15

16 rganic Chemistry II KEY March 27, 2013 Exam 2: VERSI D 16