Biochemistry Expert Answers & Study Resources

176. Why would the following synthetic route shown below be unsuccessful?     .

177. Draw all constitutional isomers of the molecular formula C6H10 that are internal alkynes.     .

151. Consider the information given below and identify the structure of the unknown compound A, with a molecular formula of C8H14.  Compound A reacts with Br2/CCl4.  Upon reaction of A with excess H2/Ni, 1-ethyl-2-methylcyclopentane is produced. Subjecting A to ozonolysis, the product shown below is produced as the major organic.

51. Rank the following acids in order of decreasing acidity. A. V > I > IV > II > III B. III > IV > II > I > V C. V > I > III > II > IV D. I > IV > V > II > III E. IV > I >.

41. Provide the IUPAC name for the following compound. 42. Provide the IUPAC name for the following compound. 43. Provide the IUPAC name for the following compound. 44. Provide the IUPAC name for the following compound: 45. Provide the IUPAC name for the following compound.     .

91. Of the reaction conditions provided below, which would be expected to convert 1 mole of 4-methyl-1-pentyne into 2-methylpentane? A. H2, Lindlar’s catalyst B. Na, NH3(l) C. 2 moles of HCl D. 2 moles H2, Pt E. 1 mole H2, Pt 92. Which reagents shown below would be expected to convert 2-pentyne to (Z)-2-pentene? A. H2, Pt B..

179. Compound X, a geminal dihalide, is exposed to excess strong base (excess NaNH2 then H2O) to produce an alkyne (compound Y). Alkyne Y is a terminal alkyne, has a molecular formula of C5H8, and has exactly 4 distinct resonances in the (proton-decoupled) 13C NMR spectrum. What are the two.

161. Which of the alkyl bromides listed would work as a reagent in step 2 of the reaction sequence shown, with the resulting major product being an internal alkyne? A. I and III B. II and IV C. III, IV, V D. I, II, IV E. II, III, V 162. Why would the following reaction sequence.

71. For the reaction shown, select the expected major organic product.   A. I B. II C. III D. IV E. V 72. For the reaction shown, select the expected major organic product.   A. I B. II C. III D. IV E. V 73. For the reaction shown, select the expected major organic product.     A. I B. II C. III D. IV E. V 74. Identify the product of.

81. For the reaction shown, select the expected major organic product. A. I B. II C. III D. IV E. V 82. For the reaction shown, select the expected major organic product. A. I B. II C. III D. IV E. V 83. How many moles of hydrogen are required for the complete reduction of 1 mole of (3E,5Z)-3-methylhepta-3,5-dien-1-yne? A. 1 B. 2 C. 3 D..

47. Rank the following carbanions in order of increasing base strength. A. I < II < III B. II < III < I C. III < II < I D. III < I < II E. II < I < III 48. Rank the following carbanions in order of increasing pKa. A. I < II < III B..

178. Draw all constitutional isomers of the molecular formula C6H10 that are terminal alkynes.     .

66. For the reaction sequence below, select the expected major product. A. 3-methylhexane B. 1-bromo-3-methylhexene C. 2-bromo-3-methylhexene D. 3-methyl-1-hexyne E. 3-methyl-2-hexyne 67. When preparing terminal alkynes by an elimination reaction, sodium amide (NaNH2) dissolved in liquid ammonia (NH3) is used most frequently. Which of the following statements offers the best explanation for the above statement? A. The.

171. Which sequence of reactions is expected to produce the product below as the final, and major, organic product? A. 1. Br2, CCl4 2. H2, Lindlar’s cat. B. 1. H2, Lindlar’s cat.; 2. Br2 C. 1. Br2, CCl4 2. Na, NH3(l) D. 1. Na, NH3(l); 2. Br2 E. 1. Br2, CCl4 2. H2, Pt 172. What.

151. Select the alkyne listed below that, upon treatment with ozone followed by water, would not produce carbon dioxide and a carboxylic acid as the final products? A. ethyne B. propyne C. 1-butyne D. 1-pentyne E. 1-hexyne 152. Which of the following alkynes, upon ozonolysis, would be expected to produce only one major organic product? A. 1-hexyne B..

166. Which sequence of reagents would be expected to accomplish the synthesis shown?   A. 1. HBr; 2. 2 NaNH2 B. 1. Br2, CCl4 2. 2 NaNH2 C. 1. Br2, H2O; 2. NaNH2 D. 1. HBr/ROOR; 2. excess NaNH2 E. 1. Na, NH3(l) 167. Which sequence of reagents would be expected to accomplish the synthesis of 1-butyne.

180. 1-Pentyne was exposed to strong base (NaNH2. then alkyl halide X, producing an internal alkyne (compound Y). Alkyne Y has exactly 4 distinct resonances in the proton-decoupled 13C NMR spectrum. What are the structures of alkyl halide X, as well as alkyne Y?     .

175. Provide the structure(s) of the expected major organic product from the following reaction sequence:     .

16. Which of the structures shown depicts the most stable carbocation intermediate formed in the hydrohalogenation reaction shown? A. I B. II C. III D. IV E. V 17. Which of the molecules below would be the expected product for the hydrohalogenation of the following alkene with HBr? A. I B. II C. III D. IV E. V 18. What is the.

116. Identify the best reagent(s) for this reaction. A. H2SO4, HgSO4, H2O B. 1. Disiamylborane, 2. HO–, H2O2 C. K2Cr2O7, H+ D. NaOCl E. H2, Pd 117. Identify the best reagent(s) for this reaction. A. H2SO4, HgSO4, H2O B. 1. Disiamylborane, 2. HO–, H2O2 C. K2Cr2O7, H+ D. NaOCl E. H2, Pd 118. Identify the final product for the following reaction. A. I B..

156. What is the IUPAC name for the expected product of the reaction below? A. propyne B. 1-hexyne C. 2-hexyne D. 3-hexyne E. (E)-3-hexyne 157. What is the IUPAC name for the expected final product of the reaction below? A. 5-decyne B. 3-hexyne C. 1-octyne D. 3-octyne E. 5-octyne 158. What is the expected major final product of the reaction sequence shown.

131. Which of the following alkynes would give a single product under hydroboration-oxidation conditions? A. 1-hexyne B. 2-hexyne C. 3-hexyne D. A and B would each give a single product E. A and C would each give a single product 132. Which of the alkynes below, after undergoing an acid-catalyzed hydration, would be expected to produce.

36. What is the IUPAC name for di-sec-butylacetylene? A. 2-ethyl-5-methyl-3-heptyne B. 2,7-dimethyl-4-octyne C. 3,6-dimethyl-4-octyne D. 2,5-diethyl-3-hexyne E. 2,2,5,5-tetramethyl-3-hexyne 37. Draw all of the constitutionally isomeric alkynes with molecular formula C5H8. 38. Provide the IUPAC name for CH3CH(CH3)C(CH3)2C?CCH(CH3)2. 39. Provide the IUPAC name for CH3C?CC(CH3)2CH(CH2CH3)2. 40. Provide the IUPAC name for CH3CHBrC?C(CH2)3CH3.     .

96. What is the expected major organic product from the treatment of 4-methyl-2-pentyne with hydrogen in the presence of Lindlar's catalyst? 97. What is the expected major organic product from the treatment of 4-methyl-2-pentyne with sodium metal in liquid ammonia? 98. In the reaction between an alkyne and Na metal in liquid.

26. Which of the alkenes below would be expected to produce at least one chirality center upon hydrohalogenation in the presence of peroxide? A. I B. II C. III D. IV E. V 27. Which of the given reaction schemes would produce the molecule shown below? A. I B. II C. III D. Both I and II E. Both II and.

146. Which of the following conditions effectively cleaves all three bonds of a carbon-carbon triple bond? A. HgSO4 and aqueous H2SO4 B. 1. Disiamylborane 2. H2O2, NaOH C. H2, Lindlar’s catalyst D. 1. O3 2. H2O E. Na, NH3(l) 147. Predict the major organic products of the reaction below. A. I and II B. II and III C. I.

76. Identify the product of the reaction of an alkyne with hydrogen and a metal catalyst. A. cis alkene B. trans alkene C. diene D. alkyne E. alkane 77. For the reaction shown, select the expected major organic product. A. I B. II C. III D. IV E. V 78. For the reaction shown, select the expected major organic product. A. I B. II C..

152.   How many distinct signals would appear in the (proton-decoupled) 13C NMR spectrum for the product of the following reaction? A.   3 B.   4 C.  5 D.   6 153.   How many distinct resonances would appear in the (proton-decoupled) 13C NMR spectrum for the product of the following reaction? A.   4 B.   5 C.   6 D.   7     .

56. Which statement below best explains why the Ka of acetylene is greater than that of ethylene? A. Acetylide anions are resonance stabilized. B. The 4 ? electrons of the acetylide anion better stabilize a negative charge. C. The electronegativity of sp carbons is greater than that of sp2 carbons. D. The electronegativity of.

26. What is the IUPAC name for the molecule shown below? A. 3-bromo-4-acetylenylheptane B. 3-(1-bromopropyl)-1-hexyne C. 3-bromo-4-propyl-5-hexyne D. 4-bromo-3-propyl-1-hexyne E. 4-ethynyl-5-bromo-heptane 27. Which of the following is the acceptable structure for (R)-5-bromohept-2-yne? A. I B. II C. III D. IV E. V 28. What is the IUPAC name for the molecule shown below? A. (E)-5-methyl-5-hepten-1-yne B. (Z)-5-methyl-5-hepten-1-yne C. (E)-3-methyl-2-hepten-6-yne D. (Z)-3-methyl-2-hepten-6-yne E. (E)-2-butynyl-2-butene 29. What is the IUPAC.

61. Of the species listed below, select those less basic than acetylide. A. BuLi B. NaNH2 C. NaOCH3 D. both A and C E. both B and C 62. Rank the following hydrocarbons in order of decreasing acidity (most acidic to least acidic. A. I > II > III B. I > III > II C. II >.

16. What is the IUPAC name for the molecule shown below? A. 4-ethyl-2-pentyne B. 2-ethyl-3-pentyne C. 3-methyl-4-hexyne D. 4-methyl-2-hexyne E. sec-Butylpropyne 17. Which of the following is a structure for hepta-3,6-dien-1-yne? A. I B. II C. III D. IV E. V 18. Which of the following is the structure for 2-hexyne? A. I B. II C. III D. IV 19. Which of the following is the structure.

21. Provide the IUPAC name for HC?CCH2CH2CH3. A. pentyne B. 1-pentyne C. butyne D. 1-butyne E. 2-butyne 22. Provide the IUPAC name for Cl3CCH2CH2CH2C?CH. A. 6,6,6-trichloro-1-hexyne B. 1,1,1-trichloro-5-hexyne C. 5,5,5-trichloro-1-pentyne D. 1-heptyne E. trichlorobutylacetylene 23. Provide the IUPAC name for Cl3C(CH2)4C?CH. A. 4,4,4-trichloro-1-butyne B. 1,1,1-trichloro-6-heptyne C. 1,1,1-trichloro-5-heptyne D. 6,6,6-trichloro-1-hexyne E. 7,7,7-trichloro-1-heptyne 24. Provide the IUPAC name for (CH3)2CHC?CCH2C(CH3)3. A. 1,1,5,5,5-pentamethyl-2-pentyne B. 1,1,1,5,5-pentamethyl-3-pentyne C. 2,2,6-trimethyl-4-heptyne D. 2,6,6-trimethyl-3-heptyne E. tert-butylisopropylacetylene 25. Provide the systematic IUPAC name.

86. Which of the reagents below would convert 2-pentyne to trans-2-pentene? A. NaNH2, NH3 B. Na, NH3 C. H2, Lindlar’s catalyst D. H2, Pd/C E. H2O, HgSO4/H2SO4 87. Select the best reagent to convert 3-heptyne to trans-3-heptene? A. Na/NH3 B. 1 eq. NaNH2, NH3 C. excess NaNH2, NH3 D. H2/Pt E. H2/Lindlar's catalyst 88. Select the reagent(s) expected to accomplish the reaction.

121. Identify the final product for the following reaction.   A. I B. II C. III D. IV E. V 122. Identify the final product for the following reaction. A. I B. II C. III D. IV E. V 123. Identify the final product for the following reaction. A. I B. II C. III D. IV E. V 124. For the reaction shown, which of the compounds listed would.

101. How many distinct eight-carbon hydrocarbon products would be formed in the complete hydrogenation of a mixture of 1-octyne, 2-octyne, and 3-octyne, in the presence of a palladium catalyst? A. 1 B. 2 C. 3 D. 6 E. 8 102. For the reaction shown below, the resulting stereochemistry of the expected product is best described as: A..

106. Which of the compounds shown below would be the most likely product expected from the reaction scheme shown? A. I B. II C. III D. IV E. V 107. Identify the expected major product from the treatment of 1-pentyne with 1 equivalent of HBr. A. 1-bromo-1-pentene B. 2-bromo-1-pentene C. 1,1-dibromopentane D. 2,2-dibromopentane E. 1,2-dibromopentane 108. Identify the expected major product from.

136. Identify the functional group would be expected to be found in the final product in the reaction below. A. aldehyde B. ketone C. diol D. enol E. alkene 137. What is the expected functional group produced when cyclodecyne is reacted with disiamylborane, followed with treatment of basic hydrogen peroxide? A. aldehyde B. ketone C. diol D. ether E. carboxylic acid 138..

150. For the following equation a) identify the starting material with correct stereochemistry and b) provide a complete reaction mechanism, including stereochemistry, to account for the product shown.     .

46. Draw the line-bond structure for the compound with the IUPAC name 2,5,9-trimethyl-2-decen-7-yne.     .

36. Identify the expected product(s) for the reaction shown below. A. I B. II C. III D. IV E. V 37. For the following reaction sequence provide the expected major organic product(s).  Include all stereoisomers showing relevant stereochemistry. 38. Provide the structure(s) of the expected major organic product(s) generated upon completion of the following reaction scheme: 39.   The.

115. Provide the structure(s) of the expected major organic product(s) from the following reaction:     .

21. What is the expected major product of the following reaction? A. I B. II C. III D. IV E. V 22. What is the expected major product for the following reaction? A. I B. II C. III D. IV E. V 23. Which of the molecules below arises from the anti-Markovnikov hydrohalogenation with HBr of the alkene shown? A. I B. II C. III D..

111. For the reaction shown, select the expected major organic product. A. I B. II C. III D. IV E. V 112. Which of the compounds shown below would be the most likely product expected from the reaction scheme shown? A. I and II B. III and IV C. II and III D. II and IV E. I and IV 113. Select.

141. Which of the compounds shown below would be the most likely product expected from the reaction scheme shown? A. I B. II C. III D. IV E. V 142. Give the major product from the careful addition of 1 equivalent of Br2 to the alkyne shown below. A. I B. II C. III D. IV E. V 143. Which of the.

6. Which of the following statements best describes the general reactivity of alkynes? A. An alkyne reacts as a nucleophile and is therefore electron rich. B. An alkyne reacts as a nucleophile and is therefore electron poor. C. Alkynes fail to undergo electrophilic addition reactions, unlike alkenes. D. An alkyne reacts as an electrophile.

Chapter 9 1. For 2-pentyne, which of the following describes the orbital overlap of the C2—C3 sigma bond? A. sp–sp B. sp2–sp2 C. sp3–sp3 D. p–p E. sp3–sp 2. For 2,4-hexadiyne, which of the following describes the orbital overlap of the C3—C4 sigma bond? A. sp–sp B. sp2–sp2 C. sp3–sp3 D. p–p E. sp3–sp 3. The sigma bond of an alkyne is formed.

126. Which of the ketones below could not be prepared by an acid-catalyzed hydration of an alkyne? A. I B. II C. III D. IV E. V 127. Consider the list of alkyne addition reactions below, and select all those that involve an enol intermediate. A. Hydroboration/oxidation B. HgSO4 catalyzed hydration in dilute H2SO4 C. Hydrohalogenation D. Both A and.

31. What is the expected major product(s) of HCl addition to the alkene below? A. II B. II and III C. I and IV D. V E. I and II 32. What are the expected major product(s) of HBr addition to the alkene shown below? A. I B. II C. III D. IV E. V 33. What is the major product of.

31. Which of the following is the structure for (2E,4E)-octa-2,4-dien-6-yne? A. I B. II C. III D. IV E. V 32. Which of the following is a structure for octa-3,6-dien-1-yne? A. HC?CCH=CHCH=CHCH2CH3 B. CH3CH=CHCH2C?CC?CH C. CH3CH=CHCH2CH=CHC?CH D. CH3C?CCH=CHCH=CHCH3 E. H2C=CHC?CCH2CH=CHCH3 33. Which of the following is the structure for 2,5,5‑trimethylhept‑3‑yne? A. CH3CH2CH(CH3)C?CCH2CH(CH3)2 B. CH3CH2C(CH3)2C?CCH(CH3)2 C. (CH3CH2)2C(CH3)C?CCH2CH3 D. CH3CH2C(CH3)2C?CC(CH3)3 E. CH3CH2CH2CH(CH3)C?CC(CH3)3 34. What is the IUPAC name for the.