Hydrogen Peroxide → 5-Bromo-3-(trifluoromethyl)pyrazin-2-amine

Temperature

50 °C

To a solution of 2-amino-5-bromopyrazine (174 mg, 1 mmol) in DMSO (3 ml) stifling under Ar is added ferrocene (56 mg, 0.3 mmol) and degassed for 5 minutes with Ar. 2 ml of 1N H2SO4 in DMSO is added, followed by CF3I (0.276 ml, 3 mmol) in DMSO (2 ml), giving a slight yellow solution. 0.2 ml of 30% H2O2 is added slowly, causing the reaction to go from yellow to dark green in color. The reaction was heated to 50° C. for 2 hours under Ar. After cooling to room temperature, the reaction mixture is poured into brine, and product is extracted with EtOAc (4×20 ml). The combined organic fractions are dried with magnesium sulfate, filtered, then concentrated in vacuo. The crude material was purified by flash chromatography (SiO2, Biotage SNAP 10 g, 0-50% EtOAc/hept) which yields 70 mg of title compound; m/z 242.0, 244.0 (M, M+2H)

1. customdegassed for 5 minutes with Ar
2. addition2 ml of 1N H2SO4 in DMSO is added
3. customgiving a slight yellow solution
4. customthe reaction
5. temperatureAfter cooling to room temperature
6. extractionis extracted with EtOAc (4×20 ml)
7. dry with materialThe combined organic fractions are dried with magnesium sulfate
8. filtrationfiltered
9. concentrationconcentrated in vacuo
10. customThe crude material was purified by flash chromatography (SiO2, Biotage SNAP 10 g, 0-50% EtOAc/hept) which

ORD record

ord-502cb32e004d458eacc41558af5f2121

Source dataset

uspto-grants-2014_02

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US08658661B2