2-Acetyl-3,5-dimethylpyrazine → 3,5-Dimethyl-2-(1-hydroximinoethyl)pyrazine

HRID 345007Notes

Reaction equation

HRID 345007 reaction equation
[C:1]([C:4]1[C:9]([CH3:10])=[N:8][C:7]([CH3:11])=[CH:6][N:5]=1)(=O)[CH3:2].Cl.[NH2:13][OH:14].O.O.O.C([O-])(=O)C.[Na+]>CO>[CH3:10][C:9]1[C:4]([C:1](=[N:13][OH:14])[CH3:2])=[N:5][CH:6]=[C:7]([CH3:11])[N:8]=1

Participants

5

Reactant 3

HCID 1047212-Acetyl-3,5-dimethylpyrazineHCID 443297Hydroxyamine hydrochlorideHCID 23665404Sodium Acetate Trihydrate

Product 1

HCID 1363411963,5-Dimethyl-2-(1-hydroximinoethyl)pyrazineYield 87.1%

Reagents, catalysts & solvents 1

HCID 887MethanolSolvent

Procedure

2-Acetyl-3,5-dimethylpyrazine (2.65 g), hydroxylamine hydrochloride (2.5 g) and sodium acetate trihydrate (3.5 g) were refluxed in methanol (50 ml) for 1 hour. The reaction mixture was concentrated, diluted with water (75 ml) and extracted with ethyl acetate. The combined extracts were dried and concentrated to give an oil which was triturated with ether and 60°-80° C. petrol to give 3,5-dimethyl-2-(1-hydroximinoethyl)pyrazine (2.54g, 87% yield) as a white solid (m.p. 85°-89° C.) and as a 1:1 mixture of (E/Z) isomers.

Workup

  1. concentrationThe reaction mixture was concentrated
  2. additiondiluted with water (75 ml)
  3. extractionextracted with ethyl acetate
  4. customThe combined extracts were dried
  5. concentrationconcentrated
  6. customto give an oil which
  7. customwas triturated with ether and 60°-80° C. petrol

Sources & evidence

ORD record
ord-f4f3a7eb6bc346e8a7a1214361812ec8
Source dataset
uspto-grants-1991_10
Patent number
US05055471

Reaction notes

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