Sulfuric Acid → HCID 178513810, compound

HRID 392372Notes

Reaction equation

HRID 392372 reaction equation
S(=O)(=O)(O)O.N[C:7]1[C:8]([C:14]([NH2:16])=[O:15])=[N:9][C:10]([F:13])=[CH:11][N:12]=1.N([O-])=[O:18].[Na+].C(=O)([O-])O.[Na+]>O>[F:13][C:10]1[N:9]=[C:8]([C:14]([NH2:16])=[O:15])[C:7]([OH:18])=[N:12][CH:11]=1

Participants

6

Reactant 4

HCID 1118Sulfuric AcidHCID 516892Sodium BicarbonateHCID 226628593-Amino-6-fluoropyrazine-2-carboxamideHCID 23668193Sodium Nitrite

Product 1

HCID 178513810HCID 178513810, compoundYield 78.1%

Reagents, catalysts & solvents 1

HCID 962WaterSolvent

Procedure

While keeping 285 ml of 97% sulfuric acid at 5-12° C. by cooling it with ice, 28.5 g of 3-amino-6-fluoro-2-pyrazinecarboxamide was added thereto to form a uniform solution. After adding 18.9 g of sodium nitrite to the solution at 5-12° C., the mixture thus obtained was stirred for 1.5 hours while cooling it with ice. While keeping the reaction mixture at a temperature not exceeding 10° C., the reaction mixture was dropwise added to 1.4 L of ice water, and the mixture thus formed was extracted first with one 850 mL portion and then two 200 mL portions of ethyl acetate. The organic layers thus obtained were united, 400 mL of water was added, then 160 mL of saturated aqueous solution of sodium hydrogen carbonate was added, pH was adjusted to 3.0, and the organic layer was separated. The organic layer thus obtained was washed with saturated aqueous solution of sodium chloride and dried on anhydrous magnesium sulfate, and the solvent was removed under reduced pressure. The residue thus obtained was washed with a mixture of diisopropyl ether and ethyl acetate to obtain 22.4 g of 6-fluoro-3-hydroxy-2-pyrazinecarboxamide as a solid product.

Workup

  1. customat 5-12° C.
  2. additionwas added
  3. customto form a uniform solution
  4. customthe mixture thus obtained
  5. temperaturewhile cooling it with ice
  6. customexceeding 10° C.
  7. customthe mixture thus formed
  8. extractionwas extracted first with one 850 mL portion
  9. customThe organic layers thus obtained
  10. customthe organic layer was separated
  11. customThe organic layer thus obtained
  12. washwas washed with saturated aqueous solution of sodium chloride
  13. dry with materialdried on anhydrous magnesium sulfate
  14. customthe solvent was removed under reduced pressure
  15. customThe residue thus obtained
  16. washwas washed with a mixture of diisopropyl ether and ethyl acetate

Sources & evidence

ORD record
ord-444b4a73a135474da0d796ad070786fc
Source dataset
uspto-grants-2004_10
Patent number
US06800629B2

Reaction notes

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