Sodium Nitrite → (2-Fluoro-4-methoxyphenyl)hydrazine

Participants

Reaction Conditions

Reaction Steps

To a vigorously stirred suspension of 2-fluoro-4-methoxyaniline hydrochloride (665 mg, 3.7 mmol) in conc. HCl (5.5 mL) cooled to 0° C. was added a cold solution of NaNO2 (312 mg, 4.5 mmol) in H2O (1 mL). The mixture was stirred at 0° C. for 90 min. A cold solution of SnCl2-2H2O (3.4 g, 15.0 mmol) in conc. HCl (5.5 mL) was then added slowly to the solution of diazonium salt. The reaction was allowed to warm to room temperature, stirred for 30 min and the reaction was filtered. The collected precipitate was washed on the filter with several large portions of ether and dried under vacuum. The solid was dissolved in DCM and washed saturated NaHCO3, extracted and dried using a phase separator. Evaporation gave (2-fluoro-4-methoxyphenyl)hydrazine (220 mg 38%), which was used in the next step without further purification. The procedure was adapted from J. Med. Chem. 2000, 43, 4701.

Provenance & Evidence