Methanol → 4-(4-Fluorophenyl)-3-oxo-3,4-dihydropyrazine-2-carboxylic acid

HRID 2241374Notes

Reaction equation

HRID 2241374 reaction equation
[F:1][C:2]1[CH:7]=[CH:6][C:5]([N:8]2[CH:13]=[CH:12][N:11]=[C:10](C#N)[C:9]2=[O:16])=[CH:4][CH:3]=1.[OH:17]S(O)(=O)=O.[CH3:22][OH:23]>>[F:1][C:2]1[CH:7]=[CH:6][C:5]([N:8]2[CH:13]=[CH:12][N:11]=[C:10]([C:22]([OH:17])=[O:23])[C:9]2=[O:16])=[CH:4][CH:3]=1

Participants

4

Reactant 3

HCID 887MethanolHCID 1118Sulfuric AcidHCID 673472474-(4-Fluorophenyl)-3-oxo-3,4-dihydropyrazine-2-carbonitrile

Product 1

HCID 673494894-(4-Fluorophenyl)-3-oxo-3,4-dihydropyrazine-2-carboxylic acidYield 69%

Procedure

A mixture of 4-(4-fluorophenyl)-3-oxo-3,4-dihydropyrazine-2-carbonitrile (0.42 g, 1.95 mmol) and H2SO4 (4.16 mL, 78.1 mmol) was stirred at ambient temperature for 17 hours. Then the reaction mixture (amide intermediate) was added to MeOH (50 mL), and then the reaction was heated at 70° C. for 2.5 hours. The reaction mixture was quenched with ice-water and treated with aqueous 2N NaOH solution at 0° C. The mixture was acidified with aqueous 1N HCl, extracted with EtOAc, dried over MgSO4, and concentrated to afford 0.315 g of the desired product (69% for 3-step process in one pot reaction), which was rinsed with Et2O.

Workup

  1. temperaturethe reaction was heated at 70° C. for 2.5 hours
  2. customThe reaction mixture was quenched with ice-water
  3. additiontreated with aqueous 2N NaOH solution at 0° C
  4. extractionextracted with EtOAc
  5. dry with materialdried over MgSO4
  6. concentrationconcentrated

Sources & evidence

ORD record
ord-86ef637025c3405483ed85b97ebcbf8c
Source dataset
uspto-grants-2010_05
Patent number
US07723330B2

Reaction notes

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