18-Crown-6 → Methyl 6-fluoro-3-nitro-2-pyrazinecarboxylate

HRID 392352Notes

Reaction equation

HRID 392352 reaction equation
Cl[C:2]1[N:7]=[C:6]([C:8]([O:10][CH3:11])=[O:9])[C:5]([N+:12]([O-:14])=[O:13])=[N:4][CH:3]=1.[F-:15].[K+].C1OCCOCCOCCOCCOCCOC1.C(=O)([O-])O.[Na+]>C(#N)C.O.C(OCC)(=O)C>[F:15][C:2]1[N:7]=[C:6]([C:8]([O:10][CH3:11])=[O:9])[C:5]([N+:12]([O-:14])=[O:13])=[N:4][CH:3]=1

Participants

8

Reactant 4

HCID 2855718-Crown-6HCID 516892Sodium BicarbonateHCID 522689Potassium FluorideHCID 15914238Methyl 6-chloro-3-nitropyrazine-2-carboxylate

Product 1

HCID 22662836Methyl 6-fluoro-3-nitro-2-pyrazinecarboxylateYield 32.5%

Reagents, catalysts & solvents 3

HCID 962WaterSolventHCID 6342AcetonitrileSolventHCID 8857Ethyl AcetateSolvent

Procedure

In 2.0 mL of acetonitrile was dissolved 0.1 g of methyl 6-chloro-3-nitro-2-pyrazinecarboxylate. After adding 40 mg of potassium fluoride and 61 mg of 18-crown-6-ether successively, the mixture thus obtained was stirred at room temperature for 1.5 hours. Then, a mixture of 10 mL of ethyl acetate and 10 mL of water was added, pH was adjusted to 7.0 with saturated aqueous solution of sodium hydrogen carbonate, 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 purified by silica gel chromatography [eluent: n-hexane:ethyl acetate=7:1] to obtain 0.03 g of methyl 6-fluoro-3-nitro-2-pyrazinecarboxylate as a light yellow-colored oily product.

Workup

  1. customthe mixture thus obtained
  2. additionwas added
  3. customthe organic layer was separated
  4. customThe organic layer thus obtained
  5. washwas washed with saturated aqueous solution of sodium chloride
  6. dry with materialdried on anhydrous magnesium sulfate
  7. customthe solvent was removed under reduced pressure
  8. customThe residue thus obtained
  9. customwas purified by silica gel chromatography [eluent: n-hexane:ethyl acetate=7:1]

Sources & evidence

ORD record
ord-b52e375ca6d74bc580a7aa9695eb7590
Source dataset
uspto-grants-2004_10
Patent number
US06800629B2

Reaction notes

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