Chemical Properties
Pure methylthio acetaldoxime is white or light yellow solid, mp 94～97℃[93～95℃(Z type), 47～50℃(E type)], does not decompose within 24h at 74℃; 48h at 105℃ Decompose 93%. Methomyl oxime aqueous solution, when pH=7, does not decompose within 12h; when pH=2, it decomposes 12% in 24h and 18% in 72h (both at 25°C). It is insoluble in water and easily soluble in organic solvents.
Uses
1-Methylthio acetaldoxime, referred to as Methylthio acetaldoxime.It is an intermediate with considerable economic value, which can be used in the manufacture of carbamate insecticides such as methomyl, thiodimethoxam and cotton bollcarb.
Definition
ChEBI: (methylsulfanyl)acetaldehyde oxime is an aliphatic aldoxime resulting from the formal condensation of 2-(methylsulfanyl)acetaldehyde with hydroxylamine. It is an aliphatic aldoxime and a methyl sulfide. It is functionally related to a (methylsulfanyl)acetaldehyde.
Synthesis
The key to the synthesis of methomyl is the synthesis of the intermediate Methylthio acetaldoxime. The synthesis of Methylthio acetaldoxime generally has the following five methods: ① thioacetaldoxime method; ② acetonitrile method; ③ methyl ethyl ketone method; ④ nitroethane method; ⑤ acetaldehyde method.
