Organic Chemistry II KEY February 22, 2016

Transcription

1 rganic hemistry II KEY February 22, 2016 Exam 1: VERSI A 1. Tramadol is a drug that is used to treat moderate to severe pain. It contains two chiral centers and is sold as a racemic mixture. Both of the stereoisomers of the racemic mixture react with Pl3, Et3 to give the same tetra-substituted alkene as the major thermodynamic product. Which of the structures below represent tramadol? B & II b) I & III c) II & III d) III & IV e) II & IV 2. The products of the reaction of limonene with 1) 3 2) Zn, l (assume excess reagents) are: 2 & IV b) II & IV c) III & IV d) II & V e) III & V Limonene I. II. V. 1

2 rganic hemistry II KEY February 22, 2016 Exam 1: VERSI A 3. R-linalool (III below) is a naturally-occurring terpene that is found in sweet basil, lavender and bay laurel. It has a number of metabolites (shown below) that are generated through oxidation and reduction reactions. Rank the relative oxidation states of linalool and its metabolites from highest oxidation state to lowest oxidation state (highest >> lowest). E V. > II > V > IV > III b) I > V > II > III > IV c) I > III > V > II > IV d) V > I > III > II > IV e) I > V > III > II > IV 4. Which of the following reaction intermediates will form the fastest upon treatment of chokol B with strong acid ( + )? E 2 2 hokol B b) I & II c) I, II, & III d) III e) I, II & IV

3 rganic hemistry II KEY February 22, 2016 Exam 1: VERSI A 5. Which of the following alkenes will provide a mixture of enantiomers upon reaction with m- chloroperbenzoic acid (m-pba)? D I. Z-4R-methyl-2-phenyl-2-hexene II. E-3-methyl-2-phenyl-2-hexene Z-1-phenyl-1-hexene 4-ethyl-3-phenyl-3-hexene, II, III, IV b) II, III c) I, II d) II, III, IV e) I 6. Which of the following non-covalent interactions are possible for desvenlafaxine at p = 12? E pka = 18.1 pka =8.34 I. Intermolecular -bonding II. Intramolecular -bonding Intermolecular Ion-Dipole Intramolecular Ion-Dipole V. Intramolecular Dipole-Dipole VI. Intermolecular Dipole-Dipole pka = 10.1 Desvenlafaxine (anti-depressant), III, V b) II, IV, VI c) I, II, III, IV d) I, II, III, IV, V, VI e) I, II, III, V, VI 7. Which of the following alkene(s) is (are) generated as the major thermodynamic product(s) in the reaction of efinaconazole with Pl3, Et3? B Efinaconazole & II b) IV c) I, II & III d) III & IV e) III 2 2 3

4 rganic hemistry II KEY February 22, 2016 Exam 1: VERSI A 8. Which of the following compounds contains a tri-substituted alkene and a secondary alcohol? D I. 2-methylcyclopent-2-en-1-ol II. 1-methylcyclopent-3-en-1-ol 3-methylpent-3-en-2-ol 2-methylpent-2-en-1-ol V. 4-methylcyclopent-2-en-1-ol I b) I, III & V c) I, III & IV d) I & III e) III 9. Which of the following reaction intermediates will form in both reactions given below? l + 2 I & IV b) I & II c) I & IV d) I e) I, II, III & IV Which of the following statements is true regarding the transformation outlined below? l l A B + & V b) II & IV c) II & V d) III & IV e) I & II I. Product B is an enantiomer of the starting material. II. Products A & B are enantiomers. Products A & B are diastereomers. The reaction occurs via an S2 mechanism. V. The reaction occurs via an S1 mechanism. 4

5 rganic hemistry II KEY February 22, 2016 Exam 1: VERSI A 11. The major product(s) of the reaction of S-metaproterenol with excess Sl2 is (are) : A I. l II. l b) II c) I & III d) IV e) III Metaproterenol l l l l l l 12. Identify which structure (I, II, III, IV) of 3-(2-hydroxypropyl)phenol is dominant each of the p conditions (A, B, ) described below. (ote: pka of alcohol (acid)= 17; pka of alcohol (conjugate acid = -2.4; pka of phenol = 8) D A B p p = 1.6 p = 6.8 p = 13.1 a) A = III; B = IV; = II b) A = IV B = IV; = IV c) A = III; B = IV; = I d) A = IV; B = IV; = I e) A = IV; B = I; = I The product of the reaction of chloramphenicol with Jones reagent is: A l l a) l b) l l l hloramphenicol c) l d) l l l 2 2 e) l l 2 5

6 rganic hemistry II KEY February 22, 2016 Exam 1: VERSI A 14. The major kinetic product(s) of the reaction below is (are): E P 4 b) II c) II & III d) I & II e) I, II & III 3 I II III 15. The major product(s) of the reaction of (-) rosmarinecine with excess is (are): I. II. (-)-Rosmarinecine V b) I & IV c) I, II, III & IV d) II e) II & III 16. Which of the following reagents could be used to prepare the product below, starting with 4- methylcyclohept-3-en-1-ol? B I Zn, l II. 1. cold, dilute KMn4 2. I4 b) I & II PD, 2l2 r3, 2S4 V. +, KMn4, c) III d) IV e) I, II & V 6

7 rganic hemistry II KEY February 22, 2016 Exam 1: VERSI A 17. italopram is an antidepressant that is sold as a racemic mixture. owever, only the S-enantiomer has antidepressant activity. italopram can be synthesized through an intramolecular S2 reaction, i.e., the reaction occurs within the same molecule. Which of the following starting materials, when reacted with a, would form the active enantiomer of citalopram through an intramolecular S2 mechanism? A F I. F II. F b) III c) II d) IV e) I & III italopram F l l l l F 18. Which of the following reactions will provide a mixture of diastereomers as major products of the reaction? B P 3 cold, dilute KMn 4 b) II & III c) III d) I, II & III e) III & IV 2 S 4 7

8 rganic hemistry II KEY February 22, 2016 Exam 1: VERSI A 19. Terpineols are naturally-occurring oils with mostly pleasant aromas and are used in perfumes, cosmetics and flavorings. There are four terpineol isomers, each containing specific functional groups described and listed below as A, B, and D. Identify which of the structures below (I, II, III, IV) corresponds to each of the terpineol isomers. B A: β-terpineol: 3 alcohol, disubstituted alkene B: 4-terpineol: 3 alcohol, trisubstituted alkene : γ-terpineol: 3 alcohol, tetrasubstituted alkene D: α-terpineol: 2 alcohol, trisubstituted alkene a) A = I B = II =III D = IV b) A = III B = I = IV D = II c) A = III B = IV = I D = II d) A = II B = I = IV D = III e) A = II B = IV = I D = III 20. Match the compounds below (I, II, III, IV) with the results of the tests (A, B,, D) listed in the table. A Test A B D Result Result Result Result Jones Tests Iodoform Test omine/water Lucas Test KMn = D b) I = B II = A II = III = III = A IV = B IV = D c) I = B d) I = II = A II = B III = III = A IV = D IV = D e) I = D II = III = A IV = B 8

9 rganic hemistry II KEY February 22, 2016 Exam 1: VERSI A 21. Alclofenac is an analgesic, anti-pyretic and anti-inflammatory agent. It reacts with KMn4, but not P or Jones reagent. Treatment of alclofenac with m-pba results in formation of a mixture of enantiomers. At p = 7, alclofenac can form intermolecular ion-dipole interactions, but not intramolecular ion-dipole interactions. Which of the following compounds is alclofenac? A a) b) l c) d) e) 22. Which of the following alcohols will form a chiral 2 alkyl bromide upon reaction with P3? B & II b) II c) III d) II & IV e) I I. 3R, 4S-3,4-dimethyl-3-hexanol II. 3R-2,2-dimethyl-3-hexanol 3-methyl-3-pentanol 3S-3,5-dimethyl-3-hexanol 23. Which of the following compounds cannot undergo reaction with Pl3, Et3? E I II III IV & IV b) II & IV c) I & II d) III e) I 9

10 rganic hemistry II KEY February 22, 2016 Exam 1: VERSI A 24. Which alcohol(s) would form the fastest in the reaction of fucosterol with one equivalent of 3 + (i.e., only one alkene reacts)? Fucosterol I. II. 3 b) I & III c) II & III d) IV e) III 10

11 rganic hemistry II KEY February 22, 2016 Exam 1: VERSI A 25. Match the reaction energy diagrams to each of the reactions given below. E (Assume no rearrangements occur in any reactions) REATIS I. 1-methylcyclopentanol + l II. 1-methylcyclopentene methylcyclopentanol + 2S4 a) A = I ; B = II; = III b) A = II; B = I; = III c) A = III; B = I; = II d) A = III; B = II; = I e) A = II; B = III; = I 11