3-Phenoxybenzaldehyde

CLEAR YELLOW TO AMBER LIQUID

There are two main methods for preparing m-phenoxybenzaldehyde in industry, namely bromobenzaldehyde method and m-phenoxytoluene method, which are described below. In the bromobenzaldehyde method, benzaldehyde is slowly added to the dichloroethane in the presence of the catalyst aluminum trichloride, and then the dichloroethane solution containing bromine containing chlorine gas is slowly added dropwise. Distillation yields m-bromobenzaldehyde. Add the catalyst cuprous chloride and solvent to the potassium phenol salt, and then add m-bromobenzaldehyde dropwise. After heating and reacting for a period of time, carry out post-treatment. Distill to recover the unreacted m-bromobenzaldehyde, continue the distillation and collect 172-1176 ℃/107.8 Pa fraction is m-phenoxybenzaldehyde. This method is used abroad for production. Domestically, due to technical and equipment problems, the cost is relatively high and purification is difficult. Production was discontinued after a period of time. M-phenoxytoluene method m-phenoxytoluene is dissolved in benzene and dehydrated first, then the catalyst azobisisobutyronitrile is added, the temperature is raised to 80-84°C, chlorine gas is introduced for chlorination, and gas chromatography is used for intermediate control. After the monochloride and dichloride, and then the remaining chlorine gas, the benzene is distilled off to obtain a mixture of m-phenoxybenzyl chloride and m-phenoxybenzylidene dichloride, which is then hydrolyzed. The hydrolysis of m-phenoxytoluene chloride can be carried out by the Sommlet method, that is, by adding urotropine, glacial acetic acid, water and m-phenoxytoluene chloride to the reaction kettle, the temperature is raised to 103～108℃, and the reaction is held for 7 hours. Then after-treatment, add toluene to extract m-phenoxybenzaldehyde, then detoluene, m-phenoxybenzaldehyde to control. In addition, meta-phenoxybenzaldehyde can also be prepared by alkaline hydrolysis. Put m-phenoxytoluene chloride and 12% sodium carbonate aqueous solution into the autoclave for hydrolysis, the reaction temperature is 160℃, the pressure in the autoclave is maintained at 0.7MPa, and the heat preservation reaction is carried out for 4h, during which the carbon dioxide generated must be continuously eliminated to maintain the specified pressure After the reaction is completed, the layers are filtered. The oil layer is m-phenoxybenzyl alcohol and m-phenoxybenzaldehyde, which are further oxidized with 5% nitric acid. The reaction temperature is 92～96℃, and the reaction time is 2h. After the reaction, the layers are separated and the oil layer That is crude m-phenoxybenzaldehyde. M-phenoxybenzaldehyde can be purified by rectification or chemical method (sodium metabisulfite). No matter which method is used above, the obtained m-phenoxybenzaldehyde can not meet the technical requirements for the preparation of pyrethrins. , Jiangsu Chemical Pesticide Group Corporation introduced a set of step-by-step crystallizer controlled by DCS from abroad to purify m-phenoxybenzaldehyde, the content can reach more than 99.5%.

Deltamethrin intermediate.

Molecular Weight:198.22
XLogP3:3.4
Hydrogen Bond Acceptor Count:2
Rotatable Bond Count:3
Exact Mass:198.068079557
Monoisotopic Mass:198.068079557
Topological Polar Surface Area:26.3
Heavy Atom Count:15
Complexity:197
Covalently-Bonded Unit Count:1
Compound Is Canonicalized:Yes