BIS(A,2-DICHLORO-BENZAL)HYDRAZINE

Bis(α, 2-dichlorobenzylidene)hydrazine is prepared from bis(2-chlorobenzylidene)hydrazine and chlorine as raw materials. Put 342 L, glacial acetic acid and 53 L acetic anhydride into the chlorination kettle, open the solid feed port and put in 105kg bis(2-chlorobenzylidene)hydrazine, then close the feed port and turn on the freezing. When the temperature of the reaction liquid drops to 20°C Chlorine gas was started around around, the reaction temperature was controlled at 20-30°C, and the chlorine gas amount was 95kg. After the chlorine aeration is completed, keep it for 16 hours. After keeping the temperature, aerate, and then put the reaction material into the filter for filtration. The filtrate is sent to the distillation pot for distillation, the acetic acid is recovered for reuse, the residue is incinerated, and the filter cake is washed with a small amount of water and dried.

Bis(α,2-dichlorobenzylidene) hydrazine is an important intermediate for the synthesis of acaricide tetramazine.