(4-bromo-2,6-dichlorophenyl)hydrazine

反应条件: temp:0.00; pressure:0.00; stir:; See reaction.notes.procedure_details.

实验步骤: 20.5 parts by weight of 2,6-dichloro-4-bromophenylhydrazine and 14.5 parts by weight of allyl ethoxymethylene-2-cyanoacetate in 100 parts by volume of n-butanol were refluxed for 4 hours. The butanol was evaporated off, the oily residue was dissolved in 150 parts by volume of ether, and dry halogen chloride gas was passed in, with ice-cooling. The hydrochloride which had precipitated was stirred with saturated sodium bicarbonate solution, and the precipitate was filtered off with suction and dried under reduced pressure to give 24.8 parts by weight of allyl 5-amino-1-(2,6-dichloro-4-bromophenyl)-pyrazole-4-carboxylate of melting point 85° C. (active ingredient No.6). The butanol was evaporated off the oily residue was dissolved in 150 parts by volume of ether, and dry halogen chloride gas cooling The hydrochloride which had precipitated the precipitate was filtered off with suction dried under reduced pressure