Name | Diethyl maleate |
Synonyms | Ethyl maleate DIETHYL MALEATE Diethyl maleate Diethyl malcate diethyl but-2-enedioate kIaleins5urediαthylester Maleic acid diethyl ester MALEIC ACID DIETHYL ESTER Diethyl (2Z)-2-butenedioate diethyl (2Z)-but-2-enedioate diethylesterkyselinymaleinove Diethylester kyseliny maleinove cis-Propenoic acid diethyl ester (Z)-DIETHYL-2-HYDROXYBUTENEDIOATE (Z)-2-BUTENEDIOIC ACID DIETHYL ESTER |
CAS | 141-05-9 |
EINECS | 205-451-9 |
InChI | InChI=1/C8H12O4/c1-3-11-7(9)5-6-8(10)12-4-2/h5-6H,3-4H2,1-2H3/b6-5- |
InChIKey | IEPRKVQEAMIZSS-AATRIKPKSA-N |
Molecular Formula | C8H12O4 |
Molar Mass | 172.18 |
Density | 1.064 g/mL at 25 °C (lit.) |
Melting Point | -10 °C (lit.) |
Boling Point | 225 °C (lit.) |
Flash Point | 200°F |
Water Solubility | insoluble |
Solubility | 14mg/l |
Vapor Presure | 1 mm Hg ( 14 °C) |
Vapor Density | 5.93 (vs air) |
Appearance | Liquid |
Color | Clear |
Merck | 14,3123 |
BRN | 1100825 |
Storage Condition | Sealed in dry,Room Temperature |
Stability | Stable. Combustible. Incompatible with oxidizing agents, bases, acids, reducing agents. |
Refractive Index | n20/D 1.441(lit.) |
Physical and Chemical Properties | Density 1.064 melting point -10°C boiling point 225°C refractive index 1.438-1.442 flash point 93°C water-soluble insoluble |
Use | Used as a pesticide intermediate, for the preparation of organophosphorus pesticide malathion, can also be used in the production of spices |
Hazard Symbols | Xi - Irritant |
Risk Codes | R36 - Irritating to the eyes R43 - May cause sensitization by skin contact R52/53 - Harmful to aquatic organisms, may cause long-term adverse effects in the aquatic environment. |
Safety Description | S26 - In case of contact with eyes, rinse immediately with plenty of water and seek medical advice. S36/37 - Wear suitable protective clothing and gloves. S37 - Wear suitable gloves. S24 - Avoid contact with skin. S24/25 - Avoid contact with skin and eyes. |
UN IDs | 3334 |
WGK Germany | 2 |
RTECS | ON1225000 |
TSCA | Yes |
HS Code | 29171990 |
Toxicity | LD50 orally in rats: 0.30 g/kg (Smyth) |
LogP | 2.2 |
NIST chemical information | information provided by: webbook.nist.gov (external link) |
EPA chemical substance information | information provided by: ofmpeb.epa.gov (external link) |
Application | diethyl maleate, also known as diethyl maleate, is used in the preparation of organophosphorus pesticide malathion, and also in medicine, perfume, intermediates For Water stabilizers (organic polycarboxylic acid phosphonic acid compounds). diethyl maleate is an intermediate of high molecular compound monomer, pesticide, medicine, perfume, water stabilizer (organic polycarboxylic acid phosphonic acid compound). Mainly used for the production of organic phosphorus pesticide malathion (marathon). It is used for the preparation of malathion, an organophosphorus pesticide, and is also an intermediate for medicines, spices and Water stabilizers (organic polycarboxylic phosphonic acid compounds); can also be used for the production of spices assay ammonia and potassium. Gas chromatography stationary liquid (the highest temperature of 40 degrees C, the solvent for benzene, chloroform, ethanol). Solvents for resins and nitrocellulose, plasticizers, organic synthesis, pesticides, polymer monomers, plastic additives. used as pesticide intermediate, for the preparation of organophosphorus pesticide malathion, can also be used for the production of spices |
production method | prepared by esterification of maleic anhydride and ethanol in the presence of sulfuric acid; cation exchange resins can also be used as catalysts for exchange conversion. Industrial diethyl maleate content ≥ 98%, per ton of product consumption of maleic anhydride (95%)585kg, ethanol (95%)604kg. The preparation method is mainly prepared by esterification of maleic anhydride and ethanol in the presence of sulfuric acid. There are two kinds of this process: benzene esterification under normal pressure and non-benzene esterification under negative pressure. (1) benzene esterification under normal pressure. Add a certain amount of benzene and ethanol into the esterification reaction pot, put maleic anhydride, add concentrated sulfuric acid Dropwise under stirring, and heat with jacket steam, the reactants were subjected to an esterification reaction at about 75 °c. The generated water, benzene and ethanol were removed by three-component azeotropic distillation, and the benzene and ethanol liquid in the upper layer was refluxed into the reaction pan. After about 13-14h, when the temperature at the top of the distillation column rises to 68.2 ° C. And the water level in the lower layer of the separator no longer rises, it indicates that all the water in the reaction pot has been distilled out, and the esterification reaction is completed. The reflux was stopped, and the distillation was continued to 95-100 °c, and benzene and ethanol were distilled off. The temperature was cooled to about 50 ° C., and neutralization treatment was carried out with 5% sodium carbonate aqueous solution. After washing with water, residual benzene and ethanol were removed in vacuo to obtain diethyl maleate. (2) negative pressure non-benzene esterification of maleic anhydride and ethanol esterification under the action of sulfuric acid, under a certain vacuum and temperature, the ethanol and the water generated by the reaction are gaseous, the ethanol was then separated by a fractional distillation column and refluxed for esterification, leading to the reaction becoming complete. This method can shorten the reaction period, improve the yield and product quality, improve the operating environment, most of the domestic production plants use this method. In addition, a cation exchange resin can be used as a catalyst for exchange conversion to obtain diethyl maleate. |
autoignition temperature | 662 ° F. |