1H-Pyrazole, 4-bromo-1-methyl- → HCID 57803054, compound

Temperature

-78 °C

To a solution of 4-bromo-1-methyl-1H-pyrazole (0.98 g, 6.0 mmol) in tetrahydrofuran (10 mL) at −78° C. was added n-butyllithium (2.5 M in hexanes, 2.76 mL, 6.90 mmol) (Aldrich) dropwisely. The mixture was stirred at −78° C. for 10 minutes. To the obtained brownish solution was added a solution of 6-chloroisatin (0.5 g, 2.76 mmol) (Crescent) in tetrahydrofuran (5 mL). The reaction mixture was warmed up to room temperature and stirred at room temperature for 3 hours. The reaction was quenched with saturated aqueous ammonium chloride solution. The mixture was extracted with ethyl acetate three times. The combined organic layers were washed with water, brine, dried over Na2SO4 and concentrated. The residue was purified by chromatography (ethyl acetate:dichloromethane, 1:1 V/V) to give rac-6-chloro-3-hydroxy-3-(1-methyl-1H-pyrazol-4-yl)-1,3-dihydro-indol-2-one as a yellow solid. (Yield 0.22 g, 30%).

1. temperatureThe reaction mixture was warmed up to room temperature
2. stirringstirred at room temperature for 3 hours
3. customThe reaction was quenched with saturated aqueous ammonium chloride solution
4. extractionThe mixture was extracted with ethyl acetate three times
5. washThe combined organic layers were washed with water, brine
6. dry with materialdried over Na2SO4
7. concentrationconcentrated
8. customThe residue was purified by chromatography (ethyl acetate:dichloromethane, 1:1 V/V)

ORD record

ord-b16dd2958bb4405c9210411e1f96cc4d

Source dataset

uspto-grants-2009_08

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US07576082B2