Hydrochloric Acid → Ethyl 2-chloro-2-[2-(2,4-dichlorophenyl)hydrazinylidene]acetate

Temperature

2.5 °C

To a stirred solution of 2,4-dichloroaniline (1 g, 6.17 mmol) and concentrated hydrochloric acid (1.5 ml) in ice (1.5 ml) a solution of NaNO2 (0.460 mg, 6.68 mmol) in water (0.8 ml) is slowly added and the mixture is stirred for 1 h at 0-5° C. Then, this solution is added over a cold mixture of NaOAc (1.64 g, 19.6 mmol), ethanol (26 ml) and ethyl-2-chloro-3-oxobutanoate (1.0 g, 6.06 mmol) and let stirring for 1 hour until the formed precipitate is collected by filtration, washed with ethanol and dichloromethane and dried in vacuo to give the yellow solid ethyl 2-chloro-2-(2-(2,4-dichlorophenyl)hydrazono)acetate (70-80% yield), which is used in the next step without any further purification.

1. stirringlet stirring for 1 hour until the formed precipitate
2. filtrationis collected by filtration
3. washwashed with ethanol and dichloromethane
4. customdried in vacuo

ORD record

ord-d6b70470bf134350aac4cd0daff8c37c

Source dataset

uspto-grants-2012_01

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US08106085B2