Name | 3-hydroxy-5-methylisoxazole |
Synonyms | AGRIZOL Hymexazol TACHIGAREN Tachigaren Itachioaren TACHIGALOZE HYDROXYISOXAZOLE Hydroxyisoxazole 5-methylisoxazol-3-ol 5-METHYLISOXAZOL-3-OL 5-Methyl-3(2H)-isoxazolone 5-methyl-3(2H)-isoxazolone 3-hydroxy-5-methyl-isoxazol 3-hydroxy-5-methylisoxazole 5-Hydroxy-3-methylisoxazole 5-methyl-1,2-oxazol-3(2H)-one |
CAS | 10004-44-1 |
EINECS | 233-000-6 |
InChI | InChI=1/C4H5NO2/c1-3-2-4(6)5-7-3/h2H,1H3,(H,5,6) |
InChIKey | KGVPNLBXJKTABS-UHFFFAOYSA-N |
Molecular Formula | C4H5NO2 |
Molar Mass | 99.09 |
Density | 1.2992 (rough estimate) |
Melting Point | 80°C |
Boling Point | 185.54°C (rough estimate) |
Flash Point | 91.8°C |
Water Solubility | 65,100 mg l-1 (20 °C) |
Solubility | Soluble in alcohol, acetone, THF, chloroform |
Vapor Presure | 0.182 Pa (25 °C) |
Appearance | Powder |
Color | White to Orange |
Merck | 14,4856 |
pKa | 5.91 (weak acid) |
Storage Condition | 2-8°C |
Sensitive | Light Sensitive |
Refractive Index | 1.4170 (estimate) |
MDL | MFCD00144468 |
Physical and Chemical Properties | Pure white crystals. m. P. 86-87 °c, vapor pressure 0.1333Pa (25 °c). Soluble in acetone, methanol, ethanol and other organic solvents, 25 degrees in water solubility of 85g/L. Acid, alkali stability, non-corrosive. |
Use | Used as soil fungicide, seed treatment agent |
Risk Codes | R22 - Harmful if swallowed R41 - Risk of serious damage to eyes 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. S39 - Wear eye / face protection. S61 - Avoid release to the environment. Refer to special instructions / safety data sheets. |
WGK Germany | 3 |
RTECS | NY2932000 |
HS Code | 29349990 |
Toxicity | LD50 in male, female mice, rats (mg/kg): 2148, 1968, 4678, 3909 orally; 1297, 1167, 1924, 1884 s.c.; 445, 514, >1000, >1000 i.v.; in rats, rabbits (mg/kg): >10000, >2000 dermally (Nakamura, 1978) |
EPA chemical information | Information provided by: ofmpub.epa.gov (external link) |
toxicity | acute oral LD503112mg/kg(3909~4678 mg/kg) in rats and 2148 mg/kg(2170 mg/kg) in mice. Acute percutaneous LD50>10000mg/kg in mice and 6500mg/kg(>2000mg/kg) in rabbits. The dose of 90-day feeding test for large and mice was 150~200 mg/kg. Accumulated toxicity belongs to weak accumulation. Micronucleus and primary spermatocyte chromosome aberration test are negative. Animal tests have no teratogenic, carcinogenic and mutagenic effects. It has slight irritation to rabbit eyes and skin. Carp LC50>40mg/kg(48h). Low toxicity to birds and silkworms. |
use | systemic soil fungicide, seed detoxification agent, and promote plant growth. Hymexazol has a good control effect on soil fungi, seedling rot fungi, Pythium, Fusarium, Volcanthus, Rhizoctonia, and catapulatus. For example, to control rice seedling blight, the seedbed should be 30% 500 times of water solution, 3L per square meter, and the pesticide should be applied before or after the seedling, and repeated every week. If 100kg of sugar beet seeds are mixed with 350~750g of 70% wettable powder, sugar beet sudden fall disease can be controlled. a high-efficiency and low-toxicity internal absorption conductivity fungicide for preventing and controlling rice-cotton seedling blight, and has the function of excellent plant growth hormone. soil irrigation is carried out at 600ppm before and after rice sowing or after emergence, which has special effect on preventing and controlling rice seedling blight, and the control effect is above 93%. Using a medicament containing 300-600ppm of active ingredients to planted rice seedlings, sugar beets, saplings and other places can prevent and control diseases caused by Fusarium, Mythium, Pythium and Vogeria. Liquid medicine containing 0.5-1% active ingredients can be used as seed treatment agent for sugar beet. Used as soil fungicide and seed treatment agent |
production methods | there are two kinds of water phase method and chlorination method. Raw material consumption quota for water phase method: hydroxylamine hydrochloride 2440kg/t, ethyl acetoacetate 3900kg/t, concentrated hydrochloric acid (37%)25kg/t. preparation method-preparation of ethyl β-chlorocrotonate ethyl acetate and 0.115mol of phosphorus pentachloride are added to 40mL of benzene, stirred at -8 ~-5 ℃ for 3h, then 30mL of methanol and 30mL of aqueous solution are added to decompose oxyphosphorus chloride, and the light yellow liquid of ethyl β-chlorocrotonate is distilled under reduced pressure to obtain B. p.50 ~ 52 ℃/1.33 × 103Pa, refractive index 1.4567, yield 77% ~ 78% (literature value: B. p.51 ℃/1.33 × 103Pa, refractive index 1.4596). The preparation of β-chlorocrotonate ethyl ester can also be prepared by non-solvent method, and the post-treatment adopts water decomposition of oxyphosphorus chloride and static layering process. Operation process: Ethyl acetoacetate and 0.067mol of phosphorus pentachloride are stirred and reacted at 0 ℃ for 6 hours, the temperature is controlled not to exceed 10 ℃, water is added dropwise to decompose phosphorus oxychloride, standing for 30min, and the light yellow liquid is distilled under reduced pressure to prepare ethyl β-chlorocrotonate with 85% yield. Synthesis of hymexazol 45.2g (0.807mol) of potassium hydroxide was dissolved in 200mL of methanol, 16g (0.228mol) of hydroxylamine hydrochloride aqueous solution was added dropwise, 20g (0.133mol) of β-ethyl chlorocrotonate was added dropwise at 0~5 ℃, the reaction was stirred at 68 ℃ for 4h, 30mL of concentrated hydrochloric acid was neutralized to pH = 1 after the reaction, and the solvent was recovered by filtration and decompression distillation, the residual liquid was cooled, filtered and dried to obtain 12.2g of colorless needle-like crystals at m.p.81 ~ 82.5 ℃ (literature value: 81 ℃), with 98% purity and 90% yield. Preparation method 2: Chlorinate ethyl acetoacetate with phosphorus pentachloride to make ethyl 3, 3-dichlorobutyrate, and then react with hydroxylamine hydrochloride to generate N-hydroxy -3, 3-dichlorobutanamide, and then react with sodium hydroxide, deacidify, and cyclize to produce hydazim. Preparation method 3: 0.02mol benzyl hydroxylamine and 0.02mol diketene were added to benzene, heated and refluxed for 1h to obtain 75% benzyl acetoacetyl oxime acid. Taking 0.01mol of benzyl acetoacetyloxamic acid in methanol, in the presence of 20% Pd-C, shaking in hydrogen flow for 3h, the mixture is filtered, the filtrate is evaporated, the resulting residue is placed overnight in ethanol saturated with hydrochloric acid, and then evaporated under vacuum to obtain 71% products. |
category | pesticide |
toxicity classification | highly toxic |
acute toxicity | oral-rat LD50: 3112 mg/kg; Oral-mouse LD50: 1968 mg/kg |
flammability hazard characteristics | combustion produces toxic nitrogen oxide gas |
storage and transportation characteristics | warehouse ventilation and low temperature drying; separate from food raw materials storage and transportation |
fire extinguishing agent | dry powder, foam, sand |