Nitric Acid → 5-Bromo-4-nitroisothiazole

Temperature

70 °C

To a solution of concentrated H2SO4 (15 mL) and HNO3 (6 mL) at 0° C. was added 5-bromoisothiazole (O) (5.0 g, 29.4 mmol). The mixture was then stirred at 70° C. for 1.5 hours. After cooling to room temperature, it was poured into stirring ice water (120 mL). The mixture was then extracted with ethyl acetate twice (150 mL×2). The combined organic phases were dried over Na2SO4 and concentrated in vacuo at room temperature (25° C.). The residue was purified with flash column (eluent: 5-20% ethyl acetate/petroleum ether) to afford the product 5-bromo-4-nitroisothiazole (P) (4.4 g, 21 mmol).

1. temperatureAfter cooling to room temperature
2. additionit was poured
3. extractionThe mixture was then extracted with ethyl acetate twice (150 mL×2)
4. dry with materialThe combined organic phases were dried over Na2SO4
5. concentrationconcentrated in vacuo at room temperature (25° C.)
6. customThe residue was purified with flash column (eluent: 5-20% ethyl acetate/petroleum ether)

ORD record

ord-5db1bff6664c409f9c050b13024090a1

Source dataset

uspto-grants-2015_03

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US08969584B2