Physical and Chemical Properties | Chemical properties 2-chloro -2-methylpropofol dimer pure product is white needle crystal, m.p. 101~104 ℃, industrial product is light blue or white amorphous powder with 95% content, soluble in ether, ketone, alcohol, halogenated alkane, aromatic hydrocarbon and depolymerized. The solubility in cold ethanol is small, slightly soluble in water, and the solubility is about 1g/100mL. It is stable in a weakly acidic medium. When it is hydrolyzed by alkali, it will automatically decompose after long-term placement, sometimes spontaneously ignite, and explode at high temperature. The dimer content of this process is controlled at about 60%. |
Use | Application 2-chloro-2-methyl-propionaldoxime dimer is an important intermediate in the synthesis of pesticide Aldicarb. |
The dimer is made by the reaction of isobutyl and sodium nitrite. The reaction equation is shown in the figure:
95% sodium nitrite and industrial ethanol were added into the synthesis kettle, cooled to -18 ~-13 ℃, isobutylene was added, and 31% hydrochloric acid was added dropwise at a certain temperature. After adding the heat preservation reaction for 3 hours, open the lower valve of the reaction kettle, place the reactant in the glass-lined kettle, slowly raise the temperature, remove excess isobutylene, then put it in a filter for filtration, and wash with water to obtain 50% ~ 60% water-containing dimer. The filtrate is neutralized with sodium hydroxide to pH = 9~10, and transported to the rectification section by pump to recover 95% industrial ethanol.