Phosphorus oxychloride → Methyl 5-chloro-6-methylpyrazine-2-carboxylate

HRID 2394280Notes

Reaction equation

HRID 2394280 reaction equation
[CH3:1][C:2]1[C:3](=O)[NH:4][CH:5]=[C:6]([C:8]([O:10][CH3:11])=[O:9])[N:7]=1.O=P(Cl)(Cl)[Cl:15]>CN(C=O)C>[Cl:15][C:3]1[N:4]=[CH:5][C:6]([C:8]([O:10][CH3:11])=[O:9])=[N:7][C:2]=1[CH3:1]

Participants

4

Reactant 2

HCID 24813Phosphorus oxychlorideHCID 12619145Methyl 6-methyl-5-oxo-4,5-dihydropyrazine-2-carboxylate

Product 1

HCID 12619146Methyl 5-chloro-6-methylpyrazine-2-carboxylateYield 52%

Reagents, catalysts & solvents 1

HCID 6228DimethylformamideSolvent

Procedure

To a solution of methyl 4,5-dihydro-6-methyl-5-oxo-2-pyrazine carboxylate (M. Mano, T. Seo, K. Imai, Chem. Pharm. Bull 10:3057-3063, 1980) in DMF (20 mL) was added POCl3 (20 mL). The reaction was refluxed for 0.5 h and then poured into ice. The aqueous layer was extracted with CHCl3 dried (MgSO4) and concentrated. The residue was chromatographed (SiO2, CHCl3) to provide the title compound (2.34 g, 52% yield); m.p. 49°-50° C.

Workup

  1. temperatureThe reaction was refluxed for 0.5 h
  2. additionpoured into ice
  3. extractionThe aqueous layer was extracted with CHCl3
  4. dry with materialdried (MgSO4)
  5. concentrationconcentrated
  6. customThe residue was chromatographed (SiO2, CHCl3)

Sources & evidence

ORD record
ord-159f59913a2949d7a03cc33f37822558
Source dataset
uspto-grants-1998_09
Patent number
US05811428

Reaction notes

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