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11.1 What is wrong with the use of such names as isopropanol and tert-butanol? Answer: We should say them as isopropyl alcohol and tert-butyl alcohol. 11.2 Give bond-line formulas and appropriate names for all of the alcohols and ethers with the formulas (a) C 3 H 8 OH and (b) C 4 H 10 O (a) CH 3 CH 2 CH 2 OH propanol H 3 C C H CH 3 OH 2-propanol CH 3 OCH 2 CH 3 Ethyl methyl ether (b) CH 3 CH 2 CH 2 CH 2 OH butanol H 3 C H 2 C C H OH CH 3 2-butanol C O H H 3 C H 3 C H 3 C tert-butyl alcohol CH 3 OCH 2 CH 2 CH 3 propyl methyl ether CH 3 CH 2 OCH 2 CH 3 diethyl ether H 3 C C H CH 3 OCH 3 isopropyl methy ether OH 2-methyl-1-propanol 11.3 1,2-Propanediol and 1,3-propanediol(propylene glycol and trimethylene glycol, respectively; see Table11.2)have higher boiling points than any of the butyl alcohols, even though all of the compounds have roughly the same molecular weight. How can you explain this observation. The diols have two OH, so it can form stronger hydrogen bonding. Therefore, 1,2-Propanediol and 1,3-propanediol have higher boiling points than any of the butyl alcohols. 11.4 What products would you expect from acid-catalyzed hydration of each of the following alkene? (a) Ethene (c)2-Methylpropene (b)Propene (d)2-Methyl-1-butene (a) H 3 O OH (b) H 3 O OH (c) H 3 O OH (d) H 3 O HO 11.5 Treating 3,3-dimethyl-1-butene with dilute sulfuric acid is largely unsuccessful as a method for preparing 3,3-dimethyl-2-butanol because an isomeric compound is the major product. What is this isomeric compound and how is it formed? 3,3-dim ethyl-1-butene H O H 2,3-D im ethyl-butan-2-ol (m ain) 11.6 Starting with an appropriate alkene, show all steps in the synthesis of each of the following alcohols by oxymercuration-demercuration. (a) tert-Butyl alcohol (b) Isopropyl alcohol (c) 2-Methyl-2-butanol Answer: (a) OH tert-butyl alcohol (1) Hg(OAc) 2 /THF-H 2 O (2) NaBH 4 ,OH (b) HO Isopropyl alcohol (1) Hg(OAc) 2 /THF-H 2 O (2) NaBH 4 ,OH (c) HO 2-Methyl- 2-butanol (1) Hg(OAc) 2 /THF-H 2 O (2) NaBH 4 ,OH 11.7 When an alkene is treated with mercuric trifluoroacetate, Hg (O2CCF3)2, in THF containing an alcohol, ROH, the product is an (alkoxyalkyl) mercury compound. Treating this product with NaBH4/OH- results in the formation of an ether. The overall process is called solvomercuration-demercuration. Hg(O 2 CCF 3 ) 2 /THF-ROH solvomercuraton RO HgO 2 CCF 3 NaBH 4 ,OH- demercuraton H OR Alkene (Alkoxyalkyl)mercuric trifluoroacetate Ether a) Outline a likely mechanism for the solvomercuration step of this ether synthesis. b) Show how you would use solvomercuration-demercuration to prepare tert-butyl methyl ether. a) Step 1: O O F F F + O O F F F O O F F F Hg O O F F F Hg Step 2: Hg O O F F F Hg O O F F F Step 3: Hg O O F F F Hg O O F F F OH R R OH R OH Hg O O F F F OH Step 4(demercuration): Hg O O F F F OH H OH NaBH 4 , OH- b) The reaction is: Hg(O 2 CCF 3 ) 2 /THF-CH 3 OH solvomercuraton O HgO 2 CCF 3 NaBH 4 ,OH- demercuraton O 11.8 Starting with an appropriate alkene, show the synthesis for (a) tributylborane, (b) 11.... View Full Document

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