反応 #2507855

反応方程式

2-(3,4-Dimethylphenyl)hydrazinium chloride

ethyl acetoacetate

sodium acetate

acetic acid

→

title compound

収率 71.0%

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

収率 71.0%

溶媒

—

Petroleum ether

ethanol

反応条件

後処理

1. 1
   温度The resulting mixture was cooled
2. 2
   濃縮concentrated
3. 3
   workup.DISSOLUTIONthe residue was dissolved in dichloromethane (10 L)
4. 4
   洗浄carefully washed with saturated sodium bicarbonate (3×3 L)
5. 5
   濃縮The organic layer was concentrated
6. 6
   その他to afford a solid
7. 7
   温度under reflux
8. 8
   温度the resulting mixture was cooled
9. 9
   ろ過filtered

実験手順

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.

出典