Reaktion #2507855

Reaktionsgleichung

2-(3,4-Dimethylphenyl)hydrazinium chloride

ethyl acetoacetate

sodium acetate

acetic acid

→

title compound

Ausbeute 71.0%

1-(3,4-dimethylphenyl)-3-methyl-1H-pyrazol-5-ol

Ausbeute 71.0%

Lösungsmittel

—

Petroleum ether

ethanol

Reaktionsbedingungen

Aufarbeitung

1. 1
   TemperaturThe resulting mixture was cooled
2. 2
   Einengenconcentrated
3. 3
   workup.DISSOLUTIONthe residue was dissolved in dichloromethane (10 L)
4. 4
   Waschencarefully washed with saturated sodium bicarbonate (3×3 L)
5. 5
   EinengenThe organic layer was concentrated
6. 6
   Sonstigeto afford a solid
7. 7
   Temperaturunder reflux
8. 8
   Temperaturthe resulting mixture was cooled
9. 9
   Filtrationfiltered

Vorschrift

2-(3,4-Dimethylphenyl)hydrazinium chloride (900 g, 5.21 mol), ethyl acetoacetate (678 g, 5.21 mol), sodium acetate (428 g, 5.21 mol) and glacial acetic acid (10 L) were stirred at 118° C. for about 24 hours. The resulting mixture was cooled and concentrated, and the residue was dissolved in dichloromethane (10 L) and carefully washed with saturated sodium bicarbonate (3×3 L). The organic layer was concentrated to afford a solid. The solid was dissolved in ethanol (450 mL) under reflux. Petroleum ether (7.2 L) was slowly added, and the resulting mixture was cooled and filtered to afford the title compound (748 g, 71%). PXRD analysis provided the diffractogram as shown in FIG. 31.

Quelle