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문제 1a,b
Phenylacetone can form two different enols.
(a) Show the structures of these enols.
(b) Predict which enol will be present in the larger concentration at equilibrium.
문제 1c3
Phenylacetone can form two different enols.
(c) Propose mechanisms for the formation of the first enol in base.
문제 1c2
Phenylacetone can form two different enols.
(c) Propose mechanisms for the formation of the second enol in acid.
문제 1c4
Phenylacetone can form two different enols.
(c) Propose mechanisms for the formation of the second enol in base.
문제 1c1
Phenylacetone can form two different enols.
(c) Propose mechanisms for the formation of the first enol in acid.
문제 2a
Show each step in the mechanism of the acid-catalyzed interconversion of (R)- and (S)-3-methylpentan-2-one.
문제 2b
When cis-2,4-dimethylcyclohexanone is dissolved in aqueous ethanol containing a trace of NaOH, a mixture of cis and trans isomers results. Propose a mechanism for this isomerization.
문제 3a,b
Give the important resonance forms for the possible enolate ions of the following:
(a) acetone
(b) cyclopentanone
문제 3c
Give the important resonance forms for the possible enolate ions of the following:
(c) pentane-2,4-dione
문제 3d
Give the important resonance forms for the possible enolate ions of the following:
(d)
문제 3e
Give the important resonance forms for the possible enolate ions of the following:
(e)
문제 3f
Give the important resonance forms for the possible enolate ions of the following:
(f)
문제 5
Predict the major products of the following reactions.
문제 6
Propose a mechanism for the acid-catalyzed reaction of cyclohexanone with pyrrolidine.
문제 7
Without looking back, propose a mechanism for the hydrolysis of this iminium salt to the alkylated ketone. The first step is attack by water, followed by loss of a proton to give a carbinolamine. Protonation on nitrogen allows pyrrolidine to leave, giving the protonated ketone.
문제 8a
Give the expected products of the following acid-catalyzed reactions.
(a) acetophenone + methylamine
문제 8b
Give the expected products of the following acid-catalyzed reactions.
(b) acetophenone + dimethylamine
문제 8c
Give the expected products of the following acid-catalyzed reactions.
(c) cyclohexanone + aniline
문제 8d
Give the expected products of the following acid-catalyzed reactions.
(d) cyclohexanone + piperidine
문제 9a,b
Show how you would accomplish each conversion using an enamine synthesis with pyrrolidine as the secondary amine.
(a) cyclopentanone → 2-allylcyclopentanone
(b) pentan-3-one → 2-methyl-1-phenylpentan-3-one
문제 9c
Show how you would accomplish each conversion using an enamine synthesis with pyrrolidine as the secondary amine.
(c)
문제 11
Propose a mechanism to show how acetophenone undergoes base-promoted chlorination to give trichloroacetophenone.
문제 12
Propose a mechanism for the reaction of cyclohexyl methyl ketone with excess bromine in the presence of sodium hydroxide.
문제 13
Predict the products of the following reactions.
(a) cyclopentyl methyl ketone + excess Cl2 + excess NaOH
(b) 1-cyclopentylethanol + excess I2 + excess NaOH
(c) propiophenone + excess Br2 + excess NaOH
문제 14
Which compounds will give positive iodoform tests?
(a) 1-phenylethanol
(b) pentan-2-one
(c) pentan-2-ol
(d) pentan-3-one
(e) acetone
(f) isopropyl alcohol
문제 15
Propose a mechanism for the acid-catalyzed bromination of pentan-3-one.
문제 16
Acid-catalyzed halogenation is synthetically useful for converting ketones to α,β-unsaturated ketones, which are useful in Michael reactions (Section 22-18). Propose a method for converting cyclohexanone to cyclohex-2-en-1-one, an important synthetic starting material.
문제 17
Show the products of the reactions of these carboxylic acids with PBr3/Br2 before and after hydrolysis.
(a) pentanoic acid
(b) phenylacetic acid
(c) succinic acid
(d) oxalic acid
문제 18
Propose a mechanism for the aldol condensation of cyclohexanone. Do you expect the equilibrium to favor the reactant or the product?
문제 19a
Give the expected products for the aldol condensations of (a) propanal.
