Organic Chemistry, 7e (Wade) Chapter 11 Reactions of Alcohols 1) Classify the reaction below as an oxidation, a reduction, or neither. (CH3)2CHCH2OH → (CH3)2CHCHO A) oxidation B) reduction C) neither Answer: A Diff: 1 Section: 11.1 2) Classify the reaction below as an oxidation, a reduction, or neither. PhCO2H → PhCH2OH A) oxidation B) reduction C) neither Answer: B Diff: 1 Section: 11.1 3) Classify the reaction below as an oxidation, a reduction, or neither. cis-pent-2-ene → pentane A) oxidation B) reduction C) neither Answer: B Diff: 1 Section: 11.1 4) Which of the following reagents is not typically viewed as an oxidizing agent? A) Cl2 B) KMnO4 C) O2 D) KCl E) H2O2 Answer: D Diff: 2 Section: 11.1 1 5) Which of the following compounds has carbon in the highest oxidation state? A) CO2 B) CH3C(O)CH3 C) CH3CH2OH D) CH3C(OCH2CH3)3 Answer: A Diff: 2 Section: 11.1 6) In the chromic acid oxidation of alcohols, the chromium is: A) oxidized from Cr+3 to Cr+6. B) reduced from Cr+6 to Cr+3. C) oxidized from Cr+6 to Cr+3. D) reduced from Cr+3 to Cr+6. E) none of the above Answer: B Diff: 1 Section: 11.2 7) Which of the following alcohols will give a positive chromic acid test? A) tert-butanol B) cyclohexanol C) pentan-3-ol D) both A and B E) both B and C Answer: E Diff: 2 Section: 11.2 8) Which of the following reagents is the best choice for oxidizing a primary alcohol to an aldehyde? A) H2CrO4 B) pyridinium chlorochromate C) Na2Cr2O7, H2SO4 D) KMnO4 E) LiAlH4 Answer: B Diff: 2 Section: 11.2 2 2 (CH3)3CCH2CH2OH 3 .2 12) Provide the structure of the major organic product in the reaction below.2 11) Provide the structure of the major organic product in the reaction below.2 10) Provide the structure of the major organic product in the reaction below. Answer: Diff: 2 Section: 11.9) Which alcohol reacts most rapidly with the Lucas reagent? A) benzyl alcohol B) methanol C) 2-propanol D) isobutanol Answer: A Diff: 2 Section: 11. Diff: 2 Section: 11. Na 2Cr2O7 → H 2SO4 Answer: (CH3)3CCH2CO2H Diff: 2 Section: 11. Answer: No reaction. Answer: Diff: 2 Section: 11. Tertiary alcohols are not oxidized by PCC.2 13) Provide the structure of the major organic product in the reaction below. Answer: Diff: 2 Section: 11.14) Provide the structure of the major organic product in the reaction below. Answer: Diff: 2 Section: 11. In the oxidation of propran-1-ol.2 4 .2 16) Provide the major organic product of the following reaction. provide the structure of this ester and give the mechanism for its conversion to the intermediate aldehyde.2 15) Chromic acid oxidations are believed to proceed through a chromate ester intermediate. Answer: Diff: 2 Section: 11. H2O2. Answer: Diff: 2 Section: 11. H2SO4.and cis-1-chloro-4-methylcyclohexanes Diff: 2 Section: 11. PCC Diff: 2 Section: 11. Answer: CH3(CH2)6CHO Diff: 2 Section: 11.2 5 .2 21) Provide the name of the major organic product that results when trans-4-methylcyclohexanol is treated with Lucas reagent.2 19) Provide the structure of the major organic product that results when 3-hexanol is treated with sodium dichromate.2 20) Provide the structure of the major organic product that results when 1-octanol is treated with pyridinium chlorochromate. Answer: a mixture of trans.2 18) Provide the reagents necessary to carry out the multistep synthesis shown below. Δ 2. NaOH 4.17) Provide the major organic product of the following reaction. Answer: 1. BH3∙THF 3. Answer: CH3CH2COCH2CH2CH3 Diff: 2 Section: 11. 2 23) Provide the major organic product of the reaction shown. H3O+ or 1. Answer: Diff: 2 Section: 11. Mg. BH3 2. Et2O 3.2 25) What series of synthetic steps could be used to prepare hexan-3-ol from propan-1-ol? Answer: 1. PCC 2. CH3CH2CH2MgBr 3.22) Provide the major organic product of the reaction shown.2 24) What series of synthetic steps could be used to carry out the transformation shown below? Answer: 1. -OH 3.2 6 . PCC Diff: 1 Section: 11. HBr or PBr3 2. CH3CH2CHO Diff: 2 Section: 11. Answer: Diff: 2 Section: 11. H2O2. H2O2. Mg. H3O+ 5. CH3CH2CHO 4. CH3MgBr 7.2 27) What series of synthetic steps could be used to carry out the transformation shown below? Answer: 1.2 7 . hν 2. PBr3 or HBr 2. H2SO4. ether 3. Diff: 2 Section: 11. Cl2. PCC 2. H3O+ Diff: 2 Section: 11. Answer: No reaction occurs. PCC 6. -OH 5.26) What series of synthetic steps could be used to prepare PhCH(OH)CH2CH3 from PhCH2OH? Answer: 1. heat Diff: 2 Section: 11. heat 3. BH3 4. PCC or Na2Cr2O7 or KMnO4 Diff: 2 Section: 11. Tertiary alcohols are resistant to mild oxidation conditions.2 28) What series of synthetic steps could be used to carry out the transformation shown below? Answer: 1. CH3CH2MgBr 3. NaOEt.2 29) Name the product which results when 1-methylcyclohexanol is treated with PCC. 2 32) What series of synthetic steps could be used to prepare (CH3)2CHCHO from (CH3)3CH? Answer: 1. H+ or BH3. H+ or PCC or KMnO4 3. H3O+ Diff: 3 Section: 11. 3. H2O2.30) Describe the composition of the Jones reagent. H2O.2 31) What series of synthetic steps could be used to prepare 1-methylcyclohexanol from cyclohexene? Answer: 1. heat 3.3 8 . CH3MgI 4. BH3 4. 2. and 4 E) none of the above Answer: B Diff: 3 Section: 11. NaOEt. and 4 C) 3 D) 1. 3. Answer: Jones reagent is a dilute solution of chromic acid in acetone. Diff: 2 Section: 11. H2O. -OH 5.3 34) Which of the following oxidants will convert a primary alcohol to an aldehyde? 1) sodium dichromate /sulfuric acid 3) pyridinium chlorochromate 2) copper oxide 4) dimethylsulfoxide. PCC Diff: 3 Section: 11. oxalyl chloride A) 3 and 4 B) 2. Br2. H2O2. NaBH4 2. hν 2. Na2Cr2O7. -OH or Hg(OAc)2.2 33) Which of the following catalysts is commonly used in industry to dehydrogenate alcohols? A) CuO B) Na C) NaBH4 D) (CH3)2S E) Zn Answer: A Diff: 2 Section: 11. 3 37) The enzyme. B) a racemic mixture. Answer: A Diff: 2 Section: 11. alcohol dehydrogenase. Diff: 3 Section: 11. a normal body metabolite. How are these poisonings treated clinically? Answer: The enzyme alcohol dehydrogenase converts these compounds to toxic substances in the body. which is produced by the liver. C) a mixture of diastereomers. Answer: Diff: 2 Section: 11. Answer: acetic acid Diff: 2 Section: 11.35) Provide the structure of the major organic product in the reaction below.4 39) When (R)-butan-2-ol is treated with TsCl in pyridine. E) none of the above.5 9 . then the ethanol swamps the enzyme and the potentially deadly alcohols pass from the body unoxidized. Answer: Diff: 2 Section: 11. D) an achial compound.3 36) Provide the major organic product of the following reaction. the product formed is: A) a single enantiomer.4 38) Poisonings by methanol and ethylene glycol are relatively common. converts ethanol to __________. If the patient receives intravenous infusions of ethanol. Answer: CH3CH2OC(CH3)3 Diff: 2 Section: 11.5 43) Provide the name of the major organic product that results when cyclopentanol is subjected to the following sequence of reactions: 1.5 44) Provide the name of the major organic product that results when (R)-2-butyl tosylate is treated with sodium iodide.40) What compound is produced when (R)-pentan-2-ol is treated with TsCl followed by NaI? A) sodium (R)-pent-3-oxide B) sodium (S)-pent-2-oxide C) (R)-2-iodopentane D) (S)-2-iodopentane E) none of the above Answer: D Diff: 2 Section: 11.5 10 . pyridine. TsCl. LiAlH4.5 41) Provide the structure of the major organic product which results when ethyl tosylate is reacted with potassium t-butoxide. Answer: (S)-2-iodobutane Diff: 2 Section: 11.5 42) Provide the major organic product of the following reaction. Answer: Diff: 2 Section: 11. 2. Answer: cyclopentane Diff: 2 Section: 11. Diff: 2 Section: 11. Diff: 2 Section: 11. is a very poor leaving group. Methods to do this include protonation. a relatively strong base. Answer: The key is to convert the hydroxyl group into a better leaving group.5 49) How can the electrophilicity of hydroxyls be increased? Suggest several specific ways.5 11 . pyridine Diff: 3 Section: 11.5 46) Provide the necessary reagents for the following conversion.5 48) Why are alcohols unreactive toward nucleophilic substitution reactions? Answer: The hydroxide ion. Answer: Extensive resonance stabilization of this ion makes it a particularly good leaving group.45) Provide the major organic product of the reaction shown. and conversion to the halide. Answer: Diff: 2 Section: 11. conversion to the tosylate ester.5 2) LiAlD4 47) Draw the tosylate ion and explain why it is a particularly good leaving group. Answer: 1) TsCl. Diff: 2 Section: 11. H2SO4/heat C) 1. conc.6 12 . KMnO4 B) 1. t-butoxide/t-butanol E) 1.50) Provide the structure of the major organic product in the reaction below. Answer: Diff: 2 Section: 11. NaOCH3 2. ZnCl2/HCl D) 1. TsCl/pyridine 2. pyridinium chlorochromate 2. 1.6 53) Provide the structure of the major organic product in the reaction below. TsCl/pyridine 2.5 52) Which of the following reactions or series of reactions would reduce 3-metylbutan-2-ol into 3-methylbutane? A) 1. (CH3)2CHCH2OH Answer: (CH3)2CHCH2O. ZnCl2/HCl 2. TsCl. LiAlH4 Answer: E Diff: 2 Section: 11. acetone Answer: PhCH2CH2CN Diff: 2 Section: 11.Na+ Diff: 2 Section: 11. pyridine → 2. NaCN.5 PhCH2CH2OH 51) Provide the structure of the major organic product in the reaction below.. 7 56) Through what basic mechanism is 1-methylcyclohexanol converted to 1-bromo-1methylcyclohexane upon treatment with HBr? A) SN1 B) SN2 C) E1 D) E2 E) radical chain Answer: A Diff: 2 Section: 11.7 57) Provide the structure of the major organic product in the reaction below. Answer: Diff: 2 Section: 11. ZnCl2)? A) (CH3)3COH B) CH3CH2CH2CH2OH C) CH3CH(OH)CH2CH3 D) (CH3)2CHCH2OH Answer: A Diff: 2 Section: 11.6 55) Which of the following alcohols will react most rapidly with the Lucas reagent (HCl. Answer: Diff: 1 Section: 11.54) Provide the major organic product of the reaction shown.7 13 . 58) Provide the major organic product of the reaction shown. Answer: Diff: 3 Section: 11.7 14 . Answer: Diff: 2 Section: 11. (CH3)3CCH2OH + HBr → Answer: Diff: 3 Section: 11.7 60) Provide the structure of the major organic product in the reaction below.7 59) Predict the major product of the reaction below and provide a stepwise mechanism which accounts for its formation. Answer: A Diff: 1 Section: 11.7 63) What compound results when 1-butanol is treated with P/I2? A) CH3CH2CH2CH2I B) racemic CH3CH2CHICH3 C) CH3CH2CH2CH2OP(OH)2 D) CH3CH2CH2CH2PI2 E) Primary alcohols don't react with P/I2.7 62) It is necessary to add ZnCl2 to promote the reaction of HCl with some alcohols while these same alcohols react with HBr quite readily.is a weaker nucleophile than is Br-. Diff: 2 Section: 11. CH3(CH2)6CH2OH + HBr → Answer: Diff: 2 Section: 11. The Lewis acid ZnCl2 coordinates with the oxygen of the alcohol to increase its electrophilicity and make it a better leaving group. Answer: Cl. Explain. A) 1) BH3 2) H2O2 / NaOH 3) P. acetone D) A and C E) all of the above Answer: D Diff: 3 Section: 11.8 15 . I2 B) HI / hν C) 1) HBr / hν 2) NaI.61) Predict the major product of the reaction below and provide a stepwise mechanism which accounts for its formation.8 64) Identify the sequence of reactions that successfully completes the following transformation. 8 67) Provide the structure of the major organic product that results when 4-methyl-1-pentanol is treated with PBr3. (CH3)2CHCH2OH Answer: (CH3)2CHCH2Br Diff: 2 Section: 11. Answer: Diff: 2 Section: 11.65) Provide the structure of the major organic product in the reaction below.8 16 . Answer: Diff: 2 Section: 11.8 68) Provide the major organic product of the reaction shown.8 66) Provide the structure of the major organic product in the reaction below. Answer: (CH3)2CHCH2CH2CH2Br Diff: 2 Section: 11. 8 70) What series of synthetic steps could be used to prepare 1-bromopentane from 1bromopropane? Answer: 1. Mg.8 71) What series of synthetic steps could be used to carry out the transformation shown below? Answer: 1. HBr or PBr3 Diff: 2 Section: 11. HBr. BH3 2. ethylene oxide 3.69) Provide the major organic product of the reaction shown. -OH 3. ROOR 2. NaCN or 1. ether 2. HBr or PBr3 4. H2O2. NaCN Diff: 2 Section: 11. Answer: Diff: 2 Section: 11.8 17 . PhCH2(OH)CH3 Answer: PhCH2CHClCH3 Diff: 1 Section: 11. CH3CHO 4. Mg 3. TsCl/Pyridine 2. HCl 2. CH3CHO 4. HCl.2-dimethylpropan-1-ol (neopentyl alcohol) to 4. ZnCl2 2. NaCl E) none of the above Answer: C Diff: 2 Section: 11. which of the following would be the best synthesis of (R)-3-chloro-2. Mg 3. Mg 3.9 74) Provide the structure of the major organic product in the reaction below. CH2O 4. SOCl2 2. H3O+ Answer: C Diff: 2 Section: 11. ZnCl2 2. HCl. Mg 3. H3O+ D) 1.3-dimethylhexan-3-ol.9 18 .4dimethylpentan-2-ol? A) 1. CH3CHO 4.3-dimethylhexane? A) HCl/ZnCl2 B) PCl3 C) SOCl2 D) 1. H3O+ C) 1.72) Which set of reagents will best convert 2.9 73) Given a sample of (R)-2. H3O+ B) 1. H2SO4 C) NaBH4 followed by H3O+ D) H2SO4. pyridine followed by LiAlH4 B) Na2Cr2O7.9 77) Which of the following reagents can be used to convert cyclopentanol to cyclopentane? A) TsCl.3-dimethylpentan-2-ol D) 2-methyl-2-phenylpropan-1-ol E) both A and B Answer: B Diff: 2 Section: 11. heat followed by H2. Answer: cis-1-chloro-4-methylcyclohexane Diff: 2 Section: 11. provide the major organic product for the reaction shown below.10 78) Which of the following alcohols undergoes dehydration upon heating with concentrated H2SO4 without carbocation rearrangement? A) 2-methylhexan-3-ol B) 3-methylpentan-3-ol C) 3.10 19 .75) Provide the name of the major organic product that results when trans-4-methylcyclohexanol is treated with thionyl chloride. Answer: Diff: 2 Section: 11.9 76) With close attention to stereochemistry. Pt E) both A and D Answer: E Diff: 2 Section: 11. CH3-MgBr 3.10 80) Provide the structure of the major organic product in the reaction below. CH3-MgBr 3. H2SO4/heat Answer: D Diff: 3 Section: 11. Hg(Ac)2 (aq) 3. K2Cr3O7/acetic acid 2. Answer: Diff: 1 Section: 11.10 20 . Na° 2. NaBH4/alkalne E) 2-methylcycloxexanol 1. Answer: Diff: 2 Section: 11. H2SO4/heat 2. OsO4/H2O2 3.10 81) Provide the structure of the major organic product in the reaction below. CH3CH2I B) t-butyl alcohol 1. K2Cr3O7/acetic acid 2. H2SO4/heat 2.79) Which of the following reaction series will result in the formation of a new secondary (2°) alcohol from the beginning alcohol listed at the top? A) Ethanol 1. H3O+ D) n-butanol 1. H3O+ C) 2-propanol 1. 10 84) Which undergoes dehydration using concentrated H2SO4 faster. Answer: Diff: 2 Section: 11. Answer: Diff: 2 Section: 11. Answer: 2-methyl-2-pentene Diff: 3 Section: 11.. cyclopentanol or 1methylcyclopentanol? Explain briefly. stepwise mechanism for this process. Provide a detailed.82) Provide the major organic product of the following reaction. Diff: 2 Section: 11.10 86) Dimethyl ether (CH3OCH3) can be prepared by heating methanol in concentrated H2SO4. H2SO4.10 83) Provide the name of the major organic product that results when (R)-2-methyl-3-pentanol is heated with conc. goes via the more stable 3° carbocation Diff: 2 Section: 11. Answer: 1-methylcyclopentanol.10 85) What is Zaitsev's rule? Answer: When the product distribution of a series of isomeric alkenes is governed by their thermodynamic stabilities.10 21 . the most substituted isomer will predominate. 10 88) Provide the major organic product of the reaction shown. making ΔG for the elimination reaction more negative.11 89) Predict the outcome of the following reaction. This results in a more favorable -TΔS term.87) When an alcohol is heated in concentrated H2SO4.11 22 . Diff: 3 Section: 11. dehydration to produce both alkenes and ethers is possible. The ΔS for this process is more positive than is the case for the ether formation. Which process is more favored by higher reaction temperatures and why? Answer: Elimination to produce alkenes is favored by higher temperatures. Answer: Diff: 3 Section: 11. Answer: Diff: 2 Section: 11. 11 91) Provide a detailed. Answer: This is a pinacol rearrangement reaction where the most stable carbocation would be formed at the tertiary position in the ring. Diff: 3 Section: 11. stepwise mechanism for the reaction below.11 92) What class of organic compound is the major product of the acid catalyzed reaction of an alcohol with a carboxylic acid? A) ether B) ester C) thiol D) nitrile E) sulfonate ester Answer: B Diff: 1 Section: 11.90) Predict the major product of the following dehydration reaction.12 23 . Answer: Diff: 3 Section: 11. 12 96) Provide the name of the major organic product that results when cyclopentanol is treated with acetyl chloride. Answer: Diff: 2 Section: 11.12 95) Provide the major organic product of the following reaction.12 94) Draw the products formed in the Fischer esterification reaction between acetic acid (CH3CO2H) and cyclohexanol. Answer: Diff: 2 Section: 11.93) Name the alcohol that would be used in the Fischer esterification synthesis of ethyl propanoate (CH3CH2O2CCH2CH3).12 24 . Answer: ethanol Diff: 1 Section: 11. Answer: cyclopentyl acetate Diff: 3 Section: 11. 13 100) What type of linkage bonds the individual nucleotides together in DNA? Answer: phosphate ester Diff: 1 Section: 11.13 101) Nitroglycerine is formed by the reaction of glycerine (propane-1. Answer: Diff: 1 Section: 11.97) What reagents are necessary for the following conversion? Answer: 1) Na2Cr2O7 / H2SO4 Diff: 3 Section: 11.2. Answer: Diff: 3 Section: 11. Provide the structure of nitroglycerine.12 2) EtOH / acid catalyst 98) Predict the outcome of the following sequence of reactions.3-triol) and nitric acid.12 99) Which energetic material is a nitrate ester? A) nitroglycerin B) TNT C) RDX D) nitromethane Answer: A Diff: 2 Section: 11.13 25 . Answer: Diff: 3 Section: 11.13 103) The Williamson ether synthesis proceeds via an __________ mechanism. A) SN1 B) SN2 C) E1 D) E2 E) none of the above Answer: B Diff: 1 Section: 11. E) There is no difference in these two reactions -. and provide a mechanism for the reaction of this compound with sodium benzoate (PhCO2Na). Answer: B Diff: 3 Section: 11.14 26 .102) Draw the structure of dimethyl sulfate. which reaction is preferred and why? A) Reaction B is preferred because the oxidation step works best for primary alcohols. B) Reaction A is preferred over reaction B because the smaller methyl iodide would make a better nucleophilic target. C) Reaction A is preferred because the the formation of the carbocation would be stabilized in the benzylic position. D) Reaction B would be preferred because Iodine is a better leaving group for the SN1 reaction.14 104) In the formation of the following ether.they would give approximately the same yields. 14 107) Provide the name of the major organic product that results when cyclopentanol is subjected to the following sequence of reactions: 1. Answer: Diff: 2 Section: 11. NaH. Answer: ethoxycyclopentane Diff: 2 Section: 11.14 106) Show the most efficient use of the Williamson ether synthesis to prepare Answer: (CH3)2CHO-Na+ + CH3CH2CH2Br Diff: 2 Section: 11.14 27 . 2.14 108) Provide the major organic product of the reaction shown.105) Provide the structure of the major organic product in the reaction below. Answer: Diff: 1 Section: 11. CH3CH2Br. -OH 3. H2O2. H2O or Hg(OAc)2. NaBH4 or 1. BH3 2. Hg(OAc)2. CH3CH2OH 2.109) What series of synthetic steps could be used to carry out the transformation shown below? Answer: 1. H2O as well. CH3CH2I Note: The hydration in the second option could be accomplished with H+.14 28 . Diff: 2 Section: 11. Na 4.