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-aa2878ab10f74c10be665f72691d7a24

Source dataset

uspto-grants-2014_12

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US08901309B2