Interpretation:
The difference in reactivity between ethyl acetoacetate (cleaves at 150°C) and ethyl dimethylacetoacetate (cleaves at room temperature) with ethoxide ion is to be explained.
Concept introduction:
The attack of the base on the carbonyl carbon of the ester and subsequent elimination of ester and protonation of the anion leads to products in a reverse Claisen reaction. However if the ester has acidic α-hydrogen atoms, the base can abstract it giving a stable resonance stabilized anion. In such cases the reverse Claisen reaction will not takes place readily at room temoerature.
To explain:
The difference in reactivity between ethyl acetoacetate (cleaves at 150°C) and ethyl dimethylacetoacetate (cleaves at room temperature) with ethoxide ion.
Want to see the full answer?
Check out a sample textbook solutionChapter 23 Solutions
Organic Chemistry
- Illustrate the cope elimination is an intramolecular E2 of tertiary amine oxidesarrow_forwardWhen 3-bromopyridine is used in this reaction, stronger reaction conditions arerequired and a mixture of 3-aminopyridine and 4-aminopyridine results. Propose amechanism to explain this curious result.arrow_forwardPredict whether d-altrose exists preferentially as a pyranose or a furanose.arrow_forward
- A commonly formed side product during the Hoffman rearrangement is a urea. When butanamide is reacted with bromine in aqueous sodium hydroxide N,N-dipropylurea is obtained together with propylamine. Indicate how this product originates.arrow_forwardProvide a selective synthesisarrow_forwardLidocaine synthesis consists of two steps, 2,6-dimethylaniline (1) is treated with chloroacetyl chloride under weakly basic conditions to selectively generate amide 2. The second step of the synthetic sequence involves the alkylation of diethylamine by the alkyl chloride group in 2. Based on this can you please answer the questions below! 1. Identify all electrophilic sites in chloroacetyl chloride. 2. Assuming that the yield of your amidation reaction was 100%, how many mole equivalents of diethylamine are you using in the second step of this synthesis? 3. Indicate two differences between the IR spectra of lidocaine (3) and 2,6-dimethylaniline (1). 4. Explain how you will be able to tell that the second step of the synthetic route was successful.arrow_forward
- Thalidomide is a chiral molecule and it was identified that the R-isomerproduced the sedative properties whereas the S-isomer produced the teratogenic effects.Identify the chiral centre in the thalidomide molecule and, using your knowledge of enolisation, illustrate mechanistically, and explain, why there would be no benefit to a patient taking the chirally pure R-isomer of the drug to avoid the sideeffects of the other enantiomer.arrow_forwardThe 1H NMR spectrum of d-glucose in D2O exhibits two high-frequency doublets. What is responsible for these doublets?arrow_forwardWhich pair of Phase 2 reaction would likely to target for similar structures in a drug substance? a GSH conjugation and methylation b Glucuronic acid conjugation and Sulfation c Glycine conjugation and Acetylation d Acetylation and Methylationarrow_forward
- Sucrose, a non-reducing sugar, would not be expected to produce an osazone when treated with phenylhydrazine. Table I shows that an osazone does indeed form (in 30 minutes) and that the osazone derived from sucrose has a Melting Point identical to that of glucosazone and fructosazone. Why?arrow_forwardEsterase is an enzyme that catalyzes the hydrolysis of esters. It hydrolyzes esters of L-amino acids more rapidly than esters of d-amino acids. How can this enzyme be used to separate a racemic mixture of amino acids?arrow_forwardIs the acid-catalyzed hydrolysis of acetamide a reversible or an irreversible reaction? Explain.arrow_forward
- Organic ChemistryChemistryISBN:9781305580350Author:William H. Brown, Brent L. Iverson, Eric Anslyn, Christopher S. FootePublisher:Cengage LearningIntroduction to General, Organic and BiochemistryChemistryISBN:9781285869759Author:Frederick A. Bettelheim, William H. Brown, Mary K. Campbell, Shawn O. Farrell, Omar TorresPublisher:Cengage Learning
- EBK A SMALL SCALE APPROACH TO ORGANIC LChemistryISBN:9781305446021Author:LampmanPublisher:CENGAGE LEARNING - CONSIGNMENTMacroscale and Microscale Organic ExperimentsChemistryISBN:9781305577190Author:Kenneth L. Williamson, Katherine M. MastersPublisher:Brooks Cole