3-Fluoroaniline → (3-Fluorophenyl)hydrazine

A 10 g portion of 3-fluoroaniline was suspended in 100 ml of concentrated hydrochloric acid, 50 ml of 13% sodium nitrite aqueous solution was gradually added thereto under ice-cooling, and the mixture was stirred at the same temperature for 10 minutes. Next, a suspension consisting of 75 g of tin chloride dihydrate and 50 ml of concentrated hydrochloric acid was added thereto, and the mixture was stirred for 1 hour while gradually returning to room temperature. Under ice-cooling, the reaction solution was adjusted to a pH value of about 9 by adding sodium hydroxide and extracted with chloroform, and then the thus obtained organic layer was dried with anhydrous sodium sulfate and the solvent was evaporate d under a reduced pressure. The residue was made into hydrochloride with 1 N hydrochloric acid/ethanol and then recrystallized from an ether-ethanol mixed solvent to obtain 11 g of the title compound as a white powder.

1. temperatureunder ice-cooling
2. additionwas added
3. stirringthe mixture was stirred for 1 hour
4. customwhile gradually returning to room temperature
5. temperatureUnder ice-cooling
6. extractionextracted with chloroform
7. dry with materialthe thus obtained organic layer was dried with anhydrous sodium sulfate
8. customthe solvent was evaporate d under a reduced pressure
9. customrecrystallized from an ether-ethanol mixed solvent

ORD record

ord-63a2ca0daeb745c5ae5d99b715d2ccb5

Source dataset

uspto-grants-2003_06

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US06573377B1