Organic Chemistry Wade Test Bank

Organic Chemistry, 7e (Wade) Chapter 10 Structure and Synthesis of Alcohols 1) __________, also known as wood alcohol, is used as a fuel and as a solvent. Ingestion of this alcohol can lead to blindness and death. Answer: Methanol or methyl alcohol Diff: 1 Section: 10.1 2) __________ is dissolved in water to make the solution sold commercially as rubbing alcohol. Answer: Isopropyl alcohol or Propan-2-ol Diff: 1 Section: 10.1 3) What type of orbital do the lone pair electrons on oxygen occupy in ethanol? A) σ B) π C) p D) sp E) sp3 Answer: E Diff: 2 Section: 10.2 4) What two atomic orbitals or hybrid atomic orbitals overlap to form the C–O bond in ethanol? A) C sp2 + O sp2 B) C sp3 + O sp3 C) C sp2 + O sp3 D) C sp3 + O sp2 E) none of the above Answer: B Diff: 2 Section: 10.2 5) 2-Methylbutan-1-ol is classified as __________. A) a primary alcohol B) a secondary alcohol C) a tertiary alcohol D) a phenol E) an enol Answer: A Diff: 1 Section: 10.3

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6) 1-Methylcyclopentan-1-ol is classified as __________. A) a primary alcohol B) a secondary alcohol C) a tertiary alcohol D) a phenol E) an enol Answer: C Diff: 1 Section: 10.3 7) 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 Answer: B Diff: 2 Section: 10.3 8) What is the correct IUPAC name for the following structure?

A) (Z) 4-methyl-3-hexen-1-thiol B) (Z) 6-mercapto-3-methylhex-3-ene C) (E) 6-mercapto-3-methylhex-3-ene D) (E) 4-methylhex-3-en-1-thiol Answer: A Diff: 2 Section: 10.3 9) Provide a common name for the following structure.

Answer: ortho isopropylphenol Diff: 1 Section: 10.3 10) Consider the alcohol 3-methylpentan-3-ol. Is this alcohol primary, secondary, or tertiary? Answer: tertiary Diff: 1 Section: 10.3 2

11) Give the IUPAC name for (CH3)2C=CHCH2CH2OH. Answer: 4-methylpent-3-en-1-ol Diff: 2 Section: 10.3 12) Provide the IUPAC name for the compound below.

Answer: 3,4,5-triethyloctan-3-ol Diff: 2 Section: 10.3 13) Provide the IUPAC name for the following compound.

Answer: (E)-4,5,5-trimethyl-3-hexen-1-ol or (E)-4,5,5-trimethylhex-3-en-1-ol Diff: 2 Section: 10.3 14) Provide an acceptable name for the following compound.

Answer: benzene-1,3-diol or resorcinol Diff: 2 Section: 10.3

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15) Name the compound shown below.

Answer: 5-ethyl-3,4-dimethyl-3-octanol or 5-ethyl-3,4-dimethyloctan-3-ol Diff: 2 Section: 10.3 16) Draw (2R, 3S) 2-bromopentan-1,3-diol in a Fischer projection. Answer:

Diff: 3 Section: 10.3 17) Provide an acceptable name for the compound below. HOCH2CH2OH Answer: ethylene glycol or ethane-1,2-diol Diff: 1 Section: 10.3 18) Provide an acceptable name for the compound below. (CH3)2CHCH2OH Answer: isobutyl alcohol or 2-methylpropan-1-ol Diff: 1 Section: 10.3 19) Provide an acceptable name for the compound below.

Answer: 3-methylcyclopent-3-en-1-ol Diff: 2 Section: 10.3

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20) Provide an acceptable name for the compound below.

Answer: cis-cyclopentane-1,3-diol Diff: 2 Section: 10.3 21) Provide an acceptable name for the compound below.

Answer: meta-propylphenol or 3-propylphenol Diff: 2 Section: 10.3 22) Provide an acceptable name for the compound below.

Answer: hydroquinone or benzene-1,4-diol or 1,4-dihydroxybenzene Diff: 2 Section: 10.3 23) Provide an acceptable name for the compound below.

Answer: cis-3-chlorocyclohexan-1-ol Diff: 3 Section: 10.3 24) Provide an acceptable name for the compound below.

Answer: 4-bromo-2-propylhexan-1-ol Diff: 3 Section: 10.3 5

25) Provide an acceptable name for the compound below.

Answer: (E)-4-chloro-3-methylpent-3-en-1-ol Diff: 3 Section: 10.3 26) __________ is the major intermolecular attraction responsible for the relatively high boiling points of alcohols. Answer: Hydrogen bonding Diff: 1 Section: 10.4 27) In a 1-butanol molecule, what part of the molecule is described as hydrophilic? Answer: the -OH or hydroxyl group Diff: 1 Section: 10.4 28) In a 1-butanol molecule, what part of the molecule is described as hydrophobic? Answer: the CH3CH2CH2CH2- or butyl group Diff: 1 Section: 10.4 29) Distillation of mixtures of ethanol and water cannot increase the ethanol content of the mixture above 95% because this solution boils at a lower temperature than either pure ethanol or pure water. The term which describes this lower boiling mixture is __________. Answer: azeotrope Diff: 2 Section: 10.4 30) Arrange the following alcohols in order of increasing boiling point: (CH3)3COH, CH3(CH2)4OH, (CH3)3CCH2OH, and (CH3)2CHCH2CH2OH. Answer: (CH3)3COH < (CH3)3CCH2OH < (CH3)2CHCH2CH2OH < CH3(CH2)4OH Diff: 2 Section: 10.4 31) Which is more soluble in water, butan-1-ol or decan-1-ol? Explain briefly. Answer: Butan-1-ol is more soluble in water. Decan-1-ol's larger alkyl group makes this compound more hydrophobic which leads to increased disruption of the dipole-dipole attractions (hydrogen bonding) among neighboring water molecules. Diff: 2 Section: 10.4

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32) Identify the statement that correctly describes methanol. A) It is used in alcoholic beverages. B) It can be used as a fuel source but releases less energy than gasoline when combusted. C) It once was used as an anesthetic. D) It is also referred to as rubbing alcohol. Answer: B Diff: 1 Section: 10.5 33) __________, commonly used in automobile antifreezes, is a diol which is highly toxic if ingested. Answer: Ethylene glycol or Ethane-1,2-diol Diff: 1 Section: 10.5 34) Ethanol that contains added impurities that make it unfit for drinking is described as __________. Answer: denatured Diff: 2 Section: 10.5 35) What is synthesis gas and what commercially important alcohol is prepared from it? Answer: Synthesis gas is a mixture of carbon monoxide and molecular hydrogen, and its used to prepare methanol. Diff: 2 Section: 10.5 36) Which of the compounds below has a pKa that most closely matches the pKa of ethanol? A) water B) ammonia C) acetic acid D) phenol E) HCl Answer: A Diff: 2 Section: 10.6 37) What gaseous byproduct is evolved when sodium metal is added to ethanol? Answer: H2, molecular hydrogen Diff: 2 Section: 10.6

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38) Provide the major organic product of the following reaction.

Answer:

Diff: 2 Section: 10.6 39) Provide the major organic product of the following reaction.

Answer:

Diff: 2 Section: 10.6 40) Provide a detailed step-by-step mechanism that would account for the formation of the product in the following reaction.

Answer:

Diff: 2 Section: 10.6 8

41) Provide the major organic product of the reaction below.

Answer:

Diff: 2 Section: 10.6 42) Given the set of reactants below, complete the acid-base reaction, and indicate whether the equilibrium favors reactants or products. CH3CH2O- + NH3 Answer: CH3CH2OH + NH2-, reactants are favored at equilibrium Diff: 2 Section: 10.6 43) Given the set of reactants below, complete the acid-base reaction, and indicate whether the equilibrium favors reactants or products. CH3O- + HCl Answer: CH3OH + Cl-, products are favored at equilibrium Diff: 2 Section: 10.6 44) Which is the stronger acid, phenol or 4-nitrophenol? Answer: 4-nitrophenol Diff: 2 Section: 10.6 45) Which is the stronger acid, cyclohexanol or 2-fluorocyclohexan-1-ol? Answer: 2-fluorocyclohexan-1-ol Diff: 2 Section: 10.6 46) Explain how a mixture of phenol and cyclopentanol might be separated using differences in their solubility properties. Answer: Dissolve the mixture in an organic solvent, like ether. Place the ethereal solution into a separatory funnel. Pour an aqueous solution of NaOH into the separatory funnel as well. The phenol will be deprotonated by the NaOH, become the phenoxide, and dissolve in the aqueous layer. The two layers are then easily separated. The phenol can be recovered from the aqueous layer by acidifying it and filtering. Diff: 2 Section: 10.6 9

47) Explain why phenol is about 106 times more acidic than methanol. Use appropriate resonance structures as part of your explanation. Answer: The phenoxide ion is highly stabilized relative to methoxide through resonance delocalization of the negative charge into the aromatic ring. This stabilization makes phenoxide less reactive and a weaker base. The weaker the base, the stronger its conjugate acid.

Diff: 3 Section: 10.6 48) Which of the following reagents or sequences do not produce an alcohol or diol from an alkene starting material? A) H+, H2O B) HCO3H C) BH3.THF followed by H2O2, NaOH D) Hg(OAc)2, H2O followed by NaBH4 E) OsO4, H2O2 Answer: B Diff: 1 Section: 10.7 49) Explain why the synthetic route shown below would be unsuccessful.

Answer: The tertiary bromide is too hindered to undergo an SN2 reaction with hydroxide. However, the hydroxide is a strong base and would react with the bromide above to yield an alkene via an E2 mechanism. Diff: 2 Section: 10.7 50) Provide the name of the major organic product that results when 1-pentene is treated with aqueous acid. Answer: 2-pentanol Diff: 2 Section: 10.7

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51) Provide the name of the major organic product that results when 1-pentene is subjected to hydroboration/oxidation. Answer: 1-pentanol Diff: 2 Section: 10.7 52) Provide the reagents necessary to carry out the transformation shown below.

Answer: 1. BH3∙THF 2. H2O2, NaOH Diff: 3 Section: 10.7 53) Provide the major organic product of the following reaction.

Answer:

Diff: 3 Section: 10.7 54) Provide the reagents necessary to accomplish the following transformation. 2-methyl-2-octene to 2-methyloctan-3-ol Answer: 1. BH3 2. H2O2, -OH Diff: 2 Section: 10.7

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55) Provide the reagents necessary to convert (R)-3-methylpent-1-ene to ®-3-methylpentan-1-ol. Answer: 1. BH3 2. H2O2, NaOH Diff: 2 Section: 10.7 56) Provide the reagents necessary to convert (E)-but-2-ene to meso-butane-2,3-diol. Answer: 1. HCO3H 2. H3O+ Diff: 2 Section: 10.7 57) Provide the reagents necessary to carry out the conversion shown below.

Answer: 1. Hg(OAc)2, H2O 2. NaBH4 Diff: 2 Section: 10.7 58) Which of the following terms best describes the reactive nature of a Grignard reagent? A) carbocation B) free radical C) electrophile D) nucleophile E) carbene Answer: D Diff: 1 Section: 10.8 59) The reaction of what two compounds produces n-butyllithium? Answer: 1-bromobutane and lithium Diff: 2 Section: 10.8

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60) Complete the following reaction by providing a structure for the necessary starting material.

Answer:

Diff: 2 Section: 10.8 61) Provide the structure of the major organic product in the reaction shown below.

Answer:

Diff: 2 Section: 10.8 62) Provide the structure of the major organic product in the reaction shown below.

Answer:

Diff: 2 Section: 10.8 63) Why are ether solvents used in the preparation of Grignard and organolithium reagents? Answer: Ethers provide a polar, aprotic environment in which these species can form. The polar nature of these reagents demands a polar solvent be used to facilitate their formation. Additionally, ethers are unreactive toward strong bases and have no functional groups that react with nucleophiles. Diff: 2 Section: 10.8

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64) What series of synthetic steps could be used to carry out the transformation shown below?

Answer: 1. HBr 2. Mg, Et2O 3. D2O Diff: 2 Section: 10.8 65) Reaction of ethylmagnesium bromide with which of the following compounds yields a tertiary alcohol after quenching with aqueous acid? A) H2CO B) CH3CHO C) (CH3)2CO D) ethylene oxide E) n-butyllithium Answer: C Diff: 2 Section: 10.9 66) Reaction of ethylmagnesium bromide with which of the following compounds yields a secondary alcohol after quenching with aqueous acid? A) H2CO B) CH3CHO C) (CH3)2CO D) ethylene oxide E) n-butyllithium Answer: B Diff: 2 Section: 10.9 67) Reaction of ethylmagnesium bromide with which of the following compounds yields a primary alcohol after quenching with aqueous acid? A) ethyl acetate B) CH3CHO C) (CH3)2CO D) ethylene oxide E) n-butyllithium Answer: D Diff: 2 Section: 10.9

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68) The reaction of CH3CH2MgBr with CH3COCH2CH3 gives: A) an achiral product. B) a mixture of diastereomers. C) the racemate of a chiral product. D) a single enantiomer. E) none of the above Answer: A Diff: 2 Section: 10.9 69) What Grignard reagent and carbonyl compound could be used to prepare 1-ethylcyclohexanol? Answer:

Diff: 1 Section: 10.9 70) Provide the major organic product of the following reaction.

Answer:

Diff: 2 Section: 10.9

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71) Provide the reagents necessary to carry out the multistep synthesis shown below.

Answer: 1. Mg 2. ethylene oxide 3. H3O+ Diff: 2 Section: 10.9 72) What sequence of reagents is needed to convert 2-chlorobutane into 3-methyl-4-heptanol? Answer: 1. Mg, ether 2. CH3CH2CH2CHO 3. H+, H2O Diff: 2 Section: 10.9 73) What sequence of reagents is needed to convert benzyl bromide into 1-phenyl-2-octanol? Answer: 1. Mg, ether 2. CH3(CH2)5CHO 3. H+, H2O Diff: 2 Section: 10.9 74) Provide the major organic product of the reaction below.

Answer:

Diff: 2 Section: 10.9 16

75) Provide the major organic product of the reaction below.

Answer:

Diff: 2 Section: 10.9 76) What two combinations of Grignard and carbonyl compound can be used to prepare 3-hexanol? Answer: CH3CH2MgBr + CH3CH2CH2CHO and CH3CH2CHO + CH3CH2CH2MgBr Diff: 2 Section: 10.9 77) What combination of reagents can be used in a Grignard-based synthesis of 1-propylcyclohexanol? Answer: cyclohexanone and propylmagnesium bromide Diff: 2 Section: 10.9 78) Provide the major organic product of the reaction below.

Answer:

Diff: 2 Section: 10.9

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79) Provide the major organic product of the reaction below.

Answer:

Diff: 2 Section: 10.9 80) Name the major organic product which results when CH3CO2CH2CH3 is treated with 2 equivalents of (CH3)2CHMgBr followed by protonation with dilute acid? Answer: 2,3,4-trimethylpent-3-ol Diff: 3 Section: 10.9 81) Complete the following synthesis by providing the necessary sequence of reactants.

Answer: 1) Br2, hν Diff: 3 Section: 10.9

2) Mg, ether

3) acetaldehyde (CH3CHO)

82) How would one used a Grignard-based synthesis to accomplish the following transformation? pentanal (CH3CH2CH2CH2CHO) to heptan-3-ol Answer: 1. CH3CH2MgBr 2. H3O+ Diff: 2 Section: 10.9

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83) How would one used a Grignard-based synthesis to accomplish the following transformation? methyl isobutyrate [(CH3)2CHCO2CH3] to 3-ethyl-2-methylpentan-3-ol Answer: 1. CH3CH2MgBr (2 equivalents) 2. H3O+ Diff: 2 Section: 10.9 84) Provide the structure of the major organic product in the reaction shown below.

Answer:

Diff: 2 Section: 10.9 85) Provide the structure of the major organic product in the reaction shown below. CH3CH2CH2CHO

1. (CH3 ) 2CHMgBr

→ 2. H3O+ Answer: CH3CH2CH2CH(OH)CH(CH3)2 Diff: 2 Section: 10.9 86) Provide the structure of the major organic product in the reaction shown below.

Answer:

Diff: 2 Section: 10.9

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87) Provide the structure of the major organic product in the reaction shown below.

Answer:

Diff: 2 Section: 10.9 88) Provide the structure of the major organic product in the reaction shown below. 1. Li (CH3)2CHC1 2. 0.5 CuI → 3. CH3CH 2CH 2 I Answer: (CH3)2CHCH2CH2CH3 Diff: 2 Section: 10.9 89) Show how one might prepare 3-methylpentane by beginning with 2-iodobutane and employing the Corey-House reaction. Answer: 1. Li 2. 1/2 CuI 3. CH3CH2I Diff: 2 Section: 10.9 90) How would one used a Grignard-based synthesis to accomplish the following transformation? benzyl bromide (PhCH2Br) to 3-phenylpropan-1-ol Answer: 1. Mg, Et2O 2. ethylene oxide (oxirane) 3. H3O+ Diff: 3 Section: 10.9

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91) Provide the reagents necessary to accomplish the following transformation.

Answer: 1. O3; CH3SCH3 or hot KMnO4, -OH 2. PhMgBr 3. H3O+ Diff: 3 Section: 10.9 92) Provide a detailed, stepwise mechanism for the reaction of acetyl chloride (CH3COCl) and 2 equivalents of PhMgCl. Answer:

Diff: 3 Section: 10.9 93) Which of the following alkyl halides would be suitable to use when forming a Grignard reagent? A) BrCH2CH2CH2CN B) CH3COCH2CH2Br C) (CH3)2NCH2CH2Br D) H2NCH2CH2Br E) all of the above Answer: C Diff: 2 Section: 10.10

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94) Which of the following substrates will not form a Grignard reagent when treated with Mg/diethylether? A)

B)

C)

D)

E)

Answer: B Diff: 2 Section: 10.10 95) Which of the following solvents is best-suited to the preparation of a Grignard reagent: hexane, diethyl ether, or ethanol? Explain. Answer: The Grignard reagent is highly polar and requires a polar solvent to stabilize its formation. Hexane is nonpolar. Both diethyl ether and ethanol are polar, but ethanol is protic and contains an H that's acidic enough to react with the Grignard. Diethyl ether is the solvent of choice. Diff: 2 Section: 10.10

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96) Provide the reagents necessary to accomplish the following transformation.

Answer: 1. Mg, Et2O 2. D2O Diff: 2 Section: 10.10 97) A novice chemist wished to prepare 1-methylcyclohexane-1,4-diol from the keto alcohol shown below by treating it with the appropriate Grignard reagent. Was the chemist successful? Explain.

Answer: Unsuccessful. The Grignard would deprotonate the hydroxyl group instead of reacting at the carbonyl. Diff: 2 Section: 10.10 98) Point out the flaw in the synthetic scheme shown below.

Answer: One cannot form a Grignard reagent from a halide molecule containing an SH group. The acidity of the sulfhydryl hydrogen precludes this. Diff: 2 Section: 10.10 99) Provide the structure of the major organic product in the reaction shown below.

Answer:

Diff: 2 Section: 10.10 23

100) When a ketone is treated with LiAlH4 followed by addition of H2O, what general class of product results? A) primary alcohol B) secondary alcohol C) tertiary alcohol D) ether E) aldehyde Answer: B Diff: 1 Section: 10.11 101) When an aldehyde is treated with LiAlH4 followed by addition of H2O, what general class of product results? A) primary alcohol B) secondary alcohol C) tertiary alcohol D) ether E) ketone Answer: A Diff: 1 Section: 10.11 102) Reduction of a ketone with NaBH4 will result in the formation of A) a primary alcohol B) an alkene C) a secondary alcohol D) an alkane E) an aldehyde Answer: C Diff: 1 Section: 10.11

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103) Which of the following reactions will result in the formation of a secondary alcohol(s) in good yield? A)

B)

C)

D)

E) both A and D Answer: E Diff: 2 Section: 10.11

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104) Which series of reactions would best facilitate the following conversion?

A) 1. KMnO4 (aq) 2. Hg(OAc)2 (aq) 3. NaBH4/OHB) 1. NaBH4 2. H3PO4/△ C) 1. H3C-MgBr 2. H2O/H3O+ D) 1. NaBH4 2. HBr (g) 3. Mg/ether 4. H2O/H3O+ E) 1. Raney nickel 2. H3C-MgBr 3. H2O/H3O+ Answer: B Diff: 3 Section: 10.11 105) Provide the structure of the major organic product in the reaction below.

Answer:

Diff: 1 Section: 10.11 106) Provide the structure of the major organic product in the reaction below.

(CH3)2CHCH2CH2CHO → Answer: (CH3)2CHCH2CH2CH2OH Diff: 1 Section: 10.11 26

107) Provide the reagents necessary to carry out the transformation shown below.

Answer: 1. LiAlH4 2. H3O+ Diff: 1 Section: 10.11 108) Provide the structure of the major organic product in the reaction below.

Answer:

Diff: 2 Section: 10.11 109) In addition to the use of complex metal hydrides, what other reaction can be used to reduce aldehydes and ketones to alcohols? Answer: catalytic hydrogenation (H2, Raney Ni) Diff: 2 Section: 10.11

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110) Provide the major organic product of the following reaction.

Answer:

Diff: 2 Section: 10.11 111) Provide the structure of the major organic product in the reaction below.

Answer:

Diff: 3 Section: 10.11 112) Provide the structure of the major organic product in the reaction below.

Answer:

Diff: 3 Section: 10.11 28

113) Provide the reagents necessary to accomplish the following transformation. methyl benzoate (PhCO2CH3) to benzyl alcohol (PhCH2OH) Answer: 1. LiAlH4 2. H3O+ Diff: 1 Section: 10.11 114) Provide the structure of the major organic product in the reaction shown below.

Answer:

Diff: 2 Section: 10.11 115) Provide the structure of the major organic product in the reaction below. CH3CH2CH(CH3)CH2CO2CH3

1. LiAlH 4

2. H3O + Answer: CH3CH2CH(CH3)CH2CH2OH Diff: 3 Section: 10.11

→

116) The acidity of a thiol proton most closely resembles which of the following acids? A) phenol B) ethanol C) acetic acid D) ammonia Answer: A Diff: 2 Section: 10.12

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117) Provide an acceptable name for the compound below.

Answer: (Z)-4-methylhex-3-ene-1-thiol Diff: 3 Section: 10.12

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