Reaction #302869

ord-44311b2c45b94b29b982197b92097dfa

Reaction equation

CO
Methanol
O=S(Cl)Cl
thionyl chloride
Nc1ncccc1C(=O)O
2-aminonicotinic acid
COC(=O)c1cccnc1N
2-aminonicotinic acid methyl ester
Yield 55.0%

Conditions

Detailed conditions
See reaction.notes.procedure_details.

Workup

  1. 1
    TemperatureThe mixture was heated
  2. 2
    Temperatureto reflux
  3. 3
    Temperaturethe mixture was refluxed for 19 hours
  4. 4
    OtherThe solvent was removed under reduced pressure
  5. 5
    workup.ADDITIONThe residue was carefully treated with a satured NaHCO3 solution
  6. 6
    Extractionextracted with ethyl acetate
  7. 7
    DryingThe organic fraction was dried over magnesium sulfate
  8. 8
    Otherthe solvent was evaporated under reduced pressure

Procedure

42.4 g (356.4 mmol, 26 ml) thionyl chloride was added dropwise to a suspension of 15.0 g (108.6 mmol) 2-aminonicotinic acid in 150 ml abs. Methanol, while cooling. The mixture was heated to reflux and the mixture was refluxed for 19 hours. The evolving SO2 was scrubbed. The solvent was removed under reduced pressure after cooling down to room temperature. The residue was carefully treated with a satured NaHCO3 solution and extracted with ethyl acetate. The organic fraction was dried over magnesium sulfate and the solvent was evaporated under reduced pressure. 9.13 g (55%) of 2-aminonicotinic acid methyl ester was isolated as a pale yellow solid (m.p. 83° C.).

Source

DOI: 10.6084/m9.figshare.5104873.v1Patent: US08192918B2uspto-grants-2012_06