Skip to main content
Back

Synthesis of Amino Acids: N-Phthalimidomalonic Ester Synthesis quiz

Control buttons has been changed to "navigation" mode.
1/15
  • What two synthesis methods are combined in the N-phthalimidomalonic ester synthesis?
    The N-phthalimidomalonic ester synthesis combines Gabriel synthesis and malonic ester synthesis.
  • What is the first step in the N-phthalimidomalonic ester synthesis?
    The first step is an SN2 reaction where potassium ethylamide displaces bromine on an alpha-bromomalonic ester.
  • What product is formed after the SN2 reaction in step 1?
    The product formed is N-methylamidomalonic ester.
  • What happens during the enolization step of the synthesis?
    A strong base deprotonates the alpha carbon of the N-methylamidomalonic ester, forming an enolate ion.
  • How is the side chain introduced in the synthesis?
    The enolate ion attacks an alkyl halide in an SN2 reaction, alkylating the alpha carbon.
  • What is the purpose of acid hydrolysis in step 4a?
    Acid hydrolysis converts the esters into carboxylic acids.
  • What occurs during the decarboxylation step (4b)?
    Decarboxylation causes the loss of one carboxylic acid group as CO2, yielding the amino acid.
  • From which molecule does the amino group in the final amino acid originate?
    The amino group comes from the nitrogen atom of the phthalimide molecule.
  • What provides the base carbon skeleton of the amino acid?
    The base carbon skeleton comes from the alpha-bromomalonic ester.
  • What is the source of the side chain in the synthesized amino acid?
    The side chain is introduced from the alkyl halide used in the alkylation step.
  • What type of reaction mechanism is used to displace bromine in step 1?
    An SN2 nucleophilic substitution mechanism is used.
  • What role does potassium ethylamide play in the synthesis?
    Potassium ethylamide acts as a nucleophile, displacing bromine from the alpha-bromomalonic ester.
  • What is released during the decarboxylation step?
    CO2 (carbon dioxide) is released during decarboxylation.
  • What functional group transformation occurs during acid hydrolysis?
    Esters are transformed into carboxylic acids.
  • Why is the N-phthalimidomalonic ester synthesis important in organic chemistry?
    It demonstrates nucleophilic substitution, enolate ion chemistry, and decarboxylation, which are key concepts in amino acid synthesis and functional group transformations.