Stannous Chloride → (3-Fluoro-2-methylphenyl)hydrazine

Participants

Reaction Conditions

Reaction Steps

24 g 3-Fluoro-2-methyl-aniline was added to 120 ml 25% hydrochloric acid and the mixture cooled to 0° C. A solution of 15 g sodium nitrite in 80 ml water was added dropwise to the resulting suspension at such a rate that the temperature did not rise above 8° C. When the addition was complete, the mixture was stirred 1 h at 0° C. Whilst maintaining the mixture at 0° C., a suspension of 195 g tin (II) chloride in 230 ml 25% aqueous hydrochloric acid was added over 30 min. The mixture was stirred a further 20 min, and the precipitate that formed was filtered. The crude hydrochloride salt was partitioned between water and dichloromethane, and the pH raised to pH8 by the addition of sodium hydroxide solution followed by saturated sodium bicarbonate solution. The phases were separated, the aqueous phase extracted twice with dichloromethane and the combined organic phases dried over sodium sulfate and evaporated. The resulting solid residue was recrystallised from hexane to afford the title compound as a light brown solid (9.2 g, 34% yield, mp 69° C.; EI-MS m/e: 140.1 (M+)).

Provenance & Evidence