تفاعل #1779366
ord-f99c68e3cd58494ea85d2348797c8862
معادلة التفاعل
المتفاعلات
الكواشف
المذيبات
ظروف التفاعل
المعالجة
- 1أخرىA 250-mL flask equipped with thermometer and nitrogen bubbler
- 2درجة الحرارةwhile maintaining the temperature at 22-41° C
- 3أخرىthe ethyl acetate was removed by distillation
- 4أخرىreached 83° C.
- 5درجة الحرارةthe product slurry was cooled over about 2 h to 10° C
- 6ترشيحThe solid was collected by filtration
- 7غسيلwashed with water
- 8أخرىdried
الإجراء التجريبي
A 250-mL flask equipped with thermometer and nitrogen bubbler was charged with 6-chloro-8-methyl-2H-3,1-benzoxazine-2,4(1H)-dione (21.0 g, 0.099 mol) (i.e. the product of Example 1), ethyl acetate (100 mL), and acetic acid (12.6 g, 0.21 mol). The mixture was stirred at 22° C., and anhydrous methylamine (4.3 g, 0.14 mol) was added below the surface of the mixture in portions over 45 minutes while maintaining the temperature at 22-41° C. The mixture was held for 2 h at 40° C., then water (150 mL) was added, and the ethyl acetate was removed by distillation. When the pot temperature reached 83° C., the solution was seeded, and the product slurry was cooled over about 2 h to 10° C. The solid was collected by filtration, washed with water and dried to afford the title compound as a white crystalline solid (18.38 g, >97.4 wt. % purity by HPLC, 94% yield) melting at 143-145° C.