反应详情

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.

1. temperatureThe resulting mixture was cooled
2. concentrationconcentrated
3. dissolutionthe residue was dissolved in dichloromethane (10 L)
4. washcarefully washed with saturated sodium bicarbonate (3×3 L)
5. concentrationThe organic layer was concentrated
6. customto afford a solid
7. temperatureunder reflux
8. temperaturethe resulting mixture was cooled
9. filtrationfiltered