Guided course 03:50The Mechanism of Williamson Ether Synthesis.Johnny Betancourt2076views30rank15comments
Textbook Questionc. Give two sets of reactants (each set including an alkyl halide and a nucleophile) that could be used to synthesize the following ether: 434views
Textbook QuestionWhat is the best way to prepare the following ethers using an alkyl halide and an alkoxide ion? a. b. 675views
Textbook Question(a) Show how ethanol and cyclohexanol may be used to synthesize cyclohexyl ethyl ether (tosylation followed by the Williamson ether synthesis). (b) Why can't we synthesize this product simply by mixing the two alcohols, adding some sulfuric acid, and heating?768views
Textbook QuestionA good Williamson synthesis of ethyl methyl ether would be < of reaction> What is wrong with the following proposed synthesis of ethyl methyl ether? First, ethanol is treated with acid to protonate the hydroxy group (making it a good leaving group), and then sodium methoxide is added to displace water. < of reaction>622views1rank
Textbook QuestionPhenols (pKa ≈ 10) are more acidic than other alcohols, so they are easily deprotonated by sodium hydroxide or potassium hydroxide. The anions of phenols (phenoxide ions) can be used in the Williamson ether synthesis, especially with very reactive alkylating reagents such as dimethyl sulfate. Using phenol, dimethyl sulfate, and other necessary reagents, show how you would synthesize methyl phenyl ether.614views
Textbook Question(••) Identify the two possible combinations of haloalkane and alkoxide that can be used to make the following ether.<IMAGE>321views
Textbook Question(•••) The reaction of alkoxides with haloalkanes is not a viable way to form ethers. (a) Why? (b) Why can thioethers be formed by an analogous reaction?<IMAGE>282views
Textbook QuestionHow could the reaction in Figure 13.67(b) be modified to produce the following ether?<IMAGE>300views
Textbook QuestionShow how the following ethers might be synthesized using (1) alkoxymercuration– demercuration and (2) the Williamson synthesis. (When one of these methods cannot be used for the given ether, point out why it will not work.) (a) 2-methoxybutane (b) ethyl cyclohexyl ether (c) 1-methoxy-2-methylcyclopentane547views
Textbook QuestionThere are two different ways of making 2-ethoxyoctane from octan-2-ol using the Williamson ether synthesis. When pure ( - )-octan-2-ol of specific rotation -8.24° is treated with sodium metal and then ethyl iodide, the product is 2-ethoxyoctane with a specific rotation of -15.6°. When pure (-)-octan-2-ol is treated with tosyl chloride and pyridine and then with sodium ethoxide, the product is also 2-ethoxyoctane. Predict the rotation of the 2-ethoxyoctane made using the tosylation/sodium ethoxide procedure, and propose a detailed mechanism to support your prediction.382views
Textbook QuestionPropose a Williamson synthesis of 3-butoxy-1,1-dimethylcyclohexane from 3,3-dimethyl-cyclohexanol and butan-1-ol.564views
Textbook QuestionFluoxetine hydrochloride (Prozac®) is a widely used antidepressant. How might you stereoselectively install the indicated ether functional group (ROR) in (R)-fluoxetine?<IMAGE>350views
Textbook QuestionPredict the product when the dihydroxybenzene shown is treated with a single equivalent of both base and haloalkane.<IMAGE>322views
Textbook QuestionPredict the product of the following substitution/addition reactions involving phenoxides. [Because this problem represents a review of current and previous material, section numbers have been provided for your reference.](a) <IMAGE>323views
Textbook QuestionPredict the product of the following reactions. [Two of them are Williamson ether syntheses. Why isn't the other?].(a) <IMAGE>354views
Textbook QuestionIdentify the alkene and alcohol partners that could be used to make the following ethers.(a) <IMAGE>310views
Textbook QuestionPredict the product of the following reactions. [Two of them are Williamson ether syntheses. Why isn't the other?].(c) <IMAGE>305views
Textbook QuestionSuggest a phenoxide and an alkyl halide to make the following aryl alkyl ethers.(b) <IMAGE>371views
Textbook QuestionTwo different Williamson ether syntheses can be used to make the compound in (a). Show them. The compound in (b), however, can only be made one way. Show it and explain why a second Williamson ether synthesis is not possible.(a) <IMAGE>375views
Textbook Question(••) In contrast to Assessment 13.102, only one combination of haloalkane and alkoxide can be used in the Williamson ether synthesis to make the ether shown. Identify the combination and explain why it is the only combination that works.<IMAGE>279views
Textbook QuestionPredict the product of the following reactions. [Two of them are Williamson ether syntheses. Why isn't the other?].(b) <IMAGE>232views
Textbook Question(••••) LOOKING BACK In Chapter 12, we learned that crown ethers were used to increase the rate of S_N2 reactions (Assessment 12.80). Suggest a synthesis of 15-crown-5 using the reactions learned here in Chapter 13.<IMAGE>288views
Textbook QuestionSuggest a phenoxide and an alkyl halide to make the following aryl alkyl ethers.(a) <IMAGE>286views
Textbook Question(••••) Provide the reagents necessary to carry out the following synthesis. What is the purpose of steps (a) and (e)?(a) _____(b) _____(c) _____(d) _____(e) _____(f) _____274views
Textbook QuestionHow could you synthesize isopropyl propyl ether, using isopropyl alcohol as the only carbon-containing reagent?323views
Textbook Questiona. Draw the product of each of the following reactions:2. CH3CH2CH2OH→2. CH3Br1. NaH239views
Textbook QuestionWhat is the best way to prepare the following ethers using an alkyl halide and an alkoxide ion?c. <IMAGE>d. <IMAGE>265views
Textbook QuestionA chemist wanted to synthesize the anesthetic 2-ethoxy-2-methylpropane. He used ethoxide ion and 2-chloro-2-methylpropane for his synthesis and ended up with no ether. What was the product of his synthesis? What reagents should he have used?283views
Textbook QuestionDesign a synthesis for each of the following, using an intramolecular reaction:e. <IMAGE>273views
Textbook QuestionThe compound shown below has three different types of OH groups, all with different acidities. Show the structure produced after this compound is treated with different amounts of NaH followed by a methylating reagent. Add a brief explanation.<IMAGE>(a) 1 equivalent of NaH, followed by 1 equivalent of CH3I and heat(b) 2 equivalents of NaH, followed by 2 equivalents of CH3I and heat(c) 3 equivalents of NaH, followed by 3 equivalents of CH3I and heat286views
Textbook QuestionShow how you would use the Williamson ether synthesis to prepare the following ethers. You may use any alcohols or phenols as your organic starting materials.(d) ethyl n-propyl ether (two ways)(e) benzyl tert-butyl ether (benzyl = Ph-CH2- )408views
Textbook QuestionShow how you would accomplish the following transformations. Some of these examples require more than one step.(d) 5-chloropent-1-ene → 2-methyltetrahydrofuran 297views
Textbook QuestionShow how you would accomplish the following transformations. Some of these examples require more than one step.(e) 2-chlorohexan-1-ol → 1,2-epoxyhexane195views
Textbook QuestionA student wanted to use the Williamson ether synthesis to make (R)-2-ethoxybutane. He remembered that the Williamson synthesis involves an SN2 displacement, which takes place with inversion of configuration. He ordered a bottle of (S)-butan-2-ol for his chiral starting material. He also remembered that the SN2 goes best on primary halides and tosylates, so he made ethyl tosylate and sodium (S)-but-2-oxide. After warming these reagents together, he obtained an excellent yield of 2-ethoxybutane.(a) What enantiomer of 2-ethoxybutane did he obtain? Explain how this enantiomer results from the SN2 reaction of ethyl tosylate with sodium (S)-but-2-oxide.(b) What would have been the best synthesis of (R)-2-ethoxybutane?(c) How can this student convert the rest of his bottle of (S)-butan-2-ol to (R)-2-ethoxybutane?290views
Textbook QuestionThe Williamson ether synthesis involves the displacement of an alkyl halide or tosylate by an alkoxide ion. Would the synthesis shown be possible by making a tosylate and displacing it? If so, show the sequence of reactions. If not, explain why not and show an alternative synthesis that would be more likely to work.<IMAGE of reaction>232views
Textbook QuestionBoth LiAlH4 and Grignard reagents react with carbonyl compounds to give alkoxide ion intermediates (that become protonated in an aqueous workup). Those alkoxides can react with 1° or methyl alkyl halides or tosylates to give ethers. Show how the following ethers can be formed in this two-step process. As starting materials you may use any reactants containing 7 carbons or fewer.(a) <IMAGE>219views
Textbook QuestionShow how you would synthesize the following ethers in good yield from the indicated starting materials and any additional reagents needed.(a) cyclopentyl n-propyl ether from cyclopentanol and propan-1-ol233views
Textbook QuestionShow how the following ethers might be synthesized using(1) alkoxymercuration– demercuration and(2) the Williamson synthesis.(When one of these methods cannot be used for the given ether, point out why it will not work.)(d) 1-methoxy-1-methylcyclopentane232views
Textbook QuestionShow how the following ethers might be synthesized using(1) alkoxymercuration– demercuration and(2) the Williamson synthesis.(When one of these methods cannot be used forthe given ether, point out why it will not work.)(e) 1-isopropoxy-1-methylcyclopentane227views
Textbook QuestionShow how the following ethers might be synthesized using(1) alkoxymercuration– demercuration and(2) the Williamson synthesis.(When one of these methods cannot be used forthe given ether, point out why it will not work.)(e) 1-isopropoxy-1-methylcyclopentane179views
Textbook QuestionShow how you would synthesize the following ethers in good yield from the indicated starting materials and any additional reagents needed.(b) n-butyl phenyl ether from phenol and butan-1-ol223views
Textbook QuestionBoth LiAlH4 and Grignard reagents react with carbonyl compounds to give alkoxide ion intermediates (that become protonated in an aqueous workup). Those alkoxides can react with 1° or methyl alkyl halides or tosylates to give ethers. Show how the following ethers can be formed in this two-step process. As starting materials you may use any reactants containing 7 carbons or fewer.(b) <IMAGE>230views
Textbook QuestionBoth LiAlH4 and Grignard reagents react with carbonyl compounds to give alkoxide ion intermediates (that become protonated in an aqueous workup). Those alkoxides can react with 1° or methyl alkyl halides or tosylates to give ethers. Show how the following ethers can be formed in this two-step process. As starting materials you may use any reactants containing 7 carbons or fewer.(c) <IMAGE>169views
Textbook QuestionIn Chapter 14, we saw that Agent Orange contains (2,4,5-trichlorophenoxy) acetic acid, called 2,4,5-T. This compound is synthesized by the partial reaction of 1,2,4,5-tetrachlorobenzene with sodium hydroxide, followed by reaction with sodium chloroacetate, ClCH2CO2Na.(a) Draw the structures of these compounds, and write equations for these reactions.<IMAGE>222views
Textbook QuestionDesign a synthesis for each of the following, using an intramolecular reaction: a. 464views