反应详情

Sodium acetate (52.8 g, 644 mmol) and 4-nitro-1H-indazole (100 g, 613 mmol) were mixed with acetic acid (1000 mL) and chloroform (1000 mL) in a 5 L 4-neck flask with mechanical stirring. A solution of bromine (103 g, 644 mmol) in acetic acid (120 mL) was added over approximately 3.5 hours, while keeping the temperature below 21° C. After the addition was completed, the reaction mixture was stirred for an additional 2 hours. The reaction mixture was concentrated under reduced pressure. Water (2000 mL) was added to the residue. The yellow solids were collected by filtration and washed with water (3×1000 mL). The solids were air-dried on the filter and then under vacuum at 40° C. to give the desired product (129 g) as a yellow solid.

1. customthe temperature below 21° C
2. additionAfter the addition
3. concentrationThe reaction mixture was concentrated under reduced pressure
4. additionWater (2000 mL) was added to the residue
5. filtrationThe yellow solids were collected by filtration
6. washwashed with water (3×1000 mL)
7. customThe solids were air-dried on the
8. filtrationfilter