(2-Fluorobenzyl)hydrazine hydrochloride synthesis

Yield:1216246-45-5 56.5 g

Reaction Conditions:

with hydrazine hydrate in water at 0 - 30; for 4 h;

Steps:

1 Example-1: Preparation of (2-fluorobenzyl)hydrazine hydrochloric acid (Formula-2)

2-Fluoro benzyl chloride (100 gms) was slowly added to a pre-cooled solution of water (500 ml) and hydrazine hydrate (301.5 gms) at 0-5°C. Raised the temperature of the reaction mixture to 25-30°C and stirred for 4 hours at the same temperature. Dichloromethane was added to the reaction mixture at 25-30°C and stirred for 20 minutes at the same temperature. Both the organic and aqueous layers were separated and extracted the aqueous layer using dichloromethane. Combined the organic layers and ethyl acetate-hydrochloric acid solution (260 ml) was added at 25-30° C and stirred for 4 hours at the same temperature. Filtered the precipitated solid and washed with dichloromethane. To the obtained wet compound, isopropanol (600 ml) was added at 25-30°C. Heated the reaction mixture to 60- 65°C and stirred for 45 minutes at the same temperature. Cooled the reaction mixture to 25- 30°C and stirred for 3 hours at the same temperature. Filtered the precipitated solid and washed with isopropanol and dried to get the title compound;

References:

WO2017/25981,2017,A1 Location in patent:Page/Page column 30; 31