Nitric Acid → 5-(4-Nitrophenyl)pyrazin-2(1H)-one

HRID 542457

Reaction equation

HRID 542457 reaction equation
[C:1]1([C:7]2[N:8]=[CH:9][C:10](=[O:13])[NH:11][CH:12]=2)[CH:6]=[CH:5][CH:4]=[CH:3][CH:2]=1.S(=O)(=O)(O)O.[N+:19]([O-])([OH:21])=[O:20].N1C=CN=CC1=O>>[N+:19]([C:4]1[CH:3]=[CH:2][C:1]([C:7]2[N:8]=[CH:9][C:10](=[O:13])[NH:11][CH:12]=2)=[CH:6][CH:5]=1)([O-:21])=[O:20]

Participants

5

Reactant 4

HCID 944Nitric AcidHCID 1118Sulfuric AcidHCID 727581,2-Dihydropyrazin-2-oneHCID 5990375-phenyl-1H-pyrazin-2-one

Product 1

HCID 138535735-(4-Nitrophenyl)pyrazin-2(1H)-one

Conditions

Temperature
-10 °C

Procedure

5-Phenyl-2-(1H)-pyrazinone (56 g) was added in portions over 30 minutes to a stirred mixture of concentrated sulphuric acid (35 ml) and fuming nitric acid (200 ml). The temperature of the nitrating mixture was initially at -20° C. and care was taken to ensure that the temperature did not rise above -15° C. When the pyrazinone had completely dissolved the reaction mixture was allowed to warm to -10° C., stirred for a further 30 minutes, and poured slowly on to ice/water (1500 ml). A pale yellow solid precipitated which was collected by filtration, washed with a small amount of cold water and dried to afford 5-(4-nitrophenyl)-2-(1H)-pyrazinone (58.1 g).

Workup

  1. customwas initially at -20° C.
  2. customdid not rise above -15° C
  3. customA pale yellow solid precipitated which
  4. filtrationwas collected by filtration
  5. washwashed with a small amount of cold water
  6. customdried

Sources & evidence

ORD record
ord-7a94c9b54ff0447caccb17a35505e0a3
Source dataset
uspto-grants-1987_04
Patent number
US04657906

Linked notes

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