tert-Butylhydrazine monohydrochloride → 6-t-Butylpyrido[2,3-d]pyridazin-5(6H)-one

HRID 1291216Notes

Reaction equation

HRID 1291216 reaction equation
[CH:1]([C:3]1[C:8]([C:9]([O:11]CC)=O)=[CH:7][CH:6]=[CH:5][N:4]=1)=O.Cl.[C:15]([NH:19][NH2:20])([CH3:18])([CH3:17])[CH3:16].C([O-])(O)=O.[Na+]>C(O)(=O)C.O>[C:15]([N:19]1[C:9](=[O:11])[C:8]2[CH:7]=[CH:6][CH:5]=[N:4][C:3]=2[CH:1]=[N:20]1)([CH3:18])([CH3:17])[CH3:16]

Participants

5

Reactant 3

HCID 81889tert-Butylhydrazine monohydrochlorideHCID 516892Sodium BicarbonateHCID 15639417Ethyl 2-formylnicotinate

Product 1

HCID 189191266-t-Butylpyrido[2,3-d]pyridazin-5(6H)-one

Reagents, catalysts & solvents 1

HCID 21899381Acetic acid--water (1/1)Solvent

Procedure

In acetic acid-water (1:1) (5 ml) was dissolved ethyl 2-formyl-3-pyridinecarboxylate (1.3 g) followed by addition of t-butylhydrazine hydrochloride (1.8 g), and the mixture was refluxed with stirring for 1 hour. This reaction mixture was cooled to room temperature, adjusted to pH 5.0 with saturated aqueous NaHCO3 solution, and extracted with dichloromethane. The organic layer was washed with saturated aqueous NaCl solution, dried over anhydrous magnesium sulfate, and concentrated. The residue was dissolved in acetic acid (2 ml) and refluxed for 1 hour. This reaction mixture was cooled, adjusted to pH 5.0 with saturated aqueous NaHCO3 solution, and extracted with dichloromethane. The organic layer was washed with saturated aqueous NaCl solution, dried over anhydrous magnesium sulfate, and concentrated. The residue was purified by silica gel chromatography (n-hexane: ethyl acetate =1:1). White powder, 1.2 g. 1H-NMR (CDCl3) δ: 1.73(9H,s), 7.64(1H,dd,J=8.2&4.4Hz), 8.38(1H,s), 8.69(1H,d,J=8.2Hz), 9.03(1H,d,J=4.4Hz).

Workup

  1. temperaturethe mixture was refluxed
  2. extractionextracted with dichloromethane
  3. washThe organic layer was washed with saturated aqueous NaCl solution
  4. dry with materialdried over anhydrous magnesium sulfate
  5. concentrationconcentrated
  6. dissolutionThe residue was dissolved in acetic acid (2 ml)
  7. temperaturerefluxed for 1 hour
  8. temperatureThis reaction mixture was cooled
  9. extractionextracted with dichloromethane
  10. washThe organic layer was washed with saturated aqueous NaCl solution
  11. dry with materialdried over anhydrous magnesium sulfate
  12. concentrationconcentrated
  13. customThe residue was purified by silica gel chromatography (n-hexane: ethyl acetate =1:1)

Sources & evidence

ORD record
ord-5164297f2659475db08ab8e40261c70e
Source dataset
uspto-grants-1998_05
Patent number
US05753664

Reaction notes

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