Tin tetrachloride → (4-Bromo-2-fluorophenyl)hydrazine

Temperature

0 °C

To a mixture of 4-bromo-2-fluoroaniline (5.0 g) in concentrated hydrochloric acid (25 mL) was added a mixture of sodium nitrite (1.9 g) in water (2.5 mL) at −20° C., and the mixture was stirred at 0° C. for 30 min. The reaction mixture was added dropwise to a mixture of tin chloride (19 g) in concentrated hydrochloric acid (25 mL) at −20° C., and the mixture was stirred at room temperature for 1 hr. The precipitate was collected by filtration, and washed with diethyl ether. The obtained solid was neutralized with 10% aqueous potassium carbonate solution, and ethyl acetate was added. The insoluble material was removed by filtration, the filtrate was extracted with ethyl acetate, the extract was washed with saturated brine and dried over anhydrous magnesium sulfate, and the solvent was evaporated under reduced pressure to give the title compound (3.4 g).

1. additionwas added
2. stirringthe mixture was stirred at room temperature for 1 hr
3. filtrationThe precipitate was collected by filtration
4. washwashed with diethyl ether
5. additionwas added
6. customThe insoluble material was removed by filtration
7. extractionthe filtrate was extracted with ethyl acetate
8. washthe extract was washed with saturated brine
9. dry with materialdried over anhydrous magnesium sulfate
10. customthe solvent was evaporated under reduced pressure

ORD record

ord-76e258001ac142f1a58c3bc757b19559

Source dataset

uspto-grants-2014_09

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US08822699B2