Reacción #2507855

Ecuación de reacción

2-(3,4-Dimethylphenyl)hydrazinium chloride

ethyl acetoacetate

sodium acetate

acetic acid

→

title compound

Rendimiento 71.0%

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

Rendimiento 71.0%

Disolventes

—

Petroleum ether

ethanol

Condiciones de reacción

Tratamiento posterior

1. 1
   TemperaturaThe resulting mixture was cooled
2. 2
   Concentraciónconcentrated
3. 3
   workup.DISSOLUTIONthe residue was dissolved in dichloromethane (10 L)
4. 4
   Lavadocarefully washed with saturated sodium bicarbonate (3×3 L)
5. 5
   ConcentraciónThe organic layer was concentrated
6. 6
   Otroto afford a solid
7. 7
   Temperaturaunder reflux
8. 8
   Temperaturathe resulting mixture was cooled
9. 9
   Filtraciónfiltered

Procedimiento

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.

Fuente