| Name | SALITHION |
| Synonyms | SALITHION Fenfosphorin [2S,(-)]-2-Methoxy-4H-1,3,2-benzodioxaphosphorin-2-sulfide [2R,(+)]-2-Methoxy-4H-1,3,2-benzodioxaphosphorin-2-sulfide |
| CAS | 3811-49-2 |
| EINECS | 223-292-3 |
| Molecular Formula | C8H9O3PS |
| Molar Mass | 216.19 |
| Density | 1.37±0.1 g/cm3(Predicted) |
| Melting Point | 55-56℃ (methanol ) |
| Boling Point | approximate 274℃ |
| Water Solubility | 58mg/L(30 ºC) |
| Physical and Chemical Properties | The pure chemical product is white needle-like crystal. M. p. 55~56 ℃, vapor pressure 0.63Pa(25 ℃), soluble in acetone, benzene, ethanol, ether, soluble in cyclohexanone, toluene, xylene, isobutyl ketone, solubility in water at 30 ℃ is 50mg/L. Stable in weakly acidic or alkaline media. |
| Use | Use 1, broad-spectrum, high-efficiency, low-residue organophosphorus pesticides, with contact and stomach poison effect, and kill the eggs, knock down the role of fast. For the prevention and control of rice stem insects, Rice gall midge, Rice planthopper and other pests, with 20% emulsifiable concentrate 3.0/hm2, the effect of rice leaf. It is effective for cotton resistant cotton bollworm, pink bollworm, fruit tree rolled leaf worm, citrus scale insect, vegetable cabbage worm and underground pests. It is generally sprayed with 25% -1000 times of 2000 emulsifiable concentrate, and is disabled 10 days before harvest. 2, vegetable phosphorus is a broad-spectrum, high efficiency and low residue of organic phosphorus pesticides, mainly used for the prevention and control of crop underground damage early, especially for cotton cotton late, citrus and many kinds of pests of the fruit. |
| Risk Codes | R24/25 - R39/25 - R51/53 - Toxic to aquatic organisms, may cause long-term adverse effects in the aquatic environment. |
| Safety Description | S36/37 - Wear suitable protective clothing and gloves. S38 - In case of insufficient ventilation, wear suitable respiratory equipment. S45 - In case of accident or if you feel unwell, seek medical advice immediately (show the label whenever possible.) S61 - Avoid release to the environment. Refer to special instructions / safety data sheets. |
| UN IDs | 2783 |
| Raw Materials | THIOPHOSPHORYL CHLORIDE formaldehyde Salicylaldehyde O-methyl dichlorothiophosphate 2-Hydroxybenzyl alcohol |
| storage conditions | 0-6°C |
| morphology | neat |
| water solubility | 58mg/L(30 °C) |
| BRN | 1875270 |
| EPA chemical information | Dioxabenzofos (3811-49-2) |
Toxicity
acute oral LD50125 ~ 180 mg/kg in rats and acute percutaneous LD50490mg/kg in rats. Carp LC503.55 mg/L (48h), crucian LC502.8 mg/L (48h); Goldfish LC503.2mg/L (48h).
production method
1. The reaction of O-methylthiophosphoryl dichloride and salicylic alcohol in aqueous phase pH11-12 is synthesized. 1. Preparation of salicylic alcohol After phenol reacts with boric acid and formaldehyde, salicylic alcohol is prepared. 2. Preparation of fruit and vegetable phosphorus Salicylic alcohol reacts with O-methyl thiophosphoryl dichloride to obtain fruit and vegetable phosphorus. The preparation method is very unstable due to the nature of salicylic alcohol, easy to cause polymerization, thus affecting the purity and yield of fruit and vegetable phosphorus. In recent years, foreign countries have carried out new research on fruit and vegetable phosphorus, that is, the reaction of salicylaldehyde and methyl thiophosphoryl dichloride in alkali flow to prepare O-methyl-O-formyl phenyl thiophosphoryl chloride, and then react with borohydride in lye to obtain fruit and vegetable phosphorus.
2. preparation of salicylic alcohol 47g phenol, 31g boric acid and 25mLL toluene were heated and refluxed under stirring to remove the generated water. After dehydration, 120mL of toluene was added, 15g of purified formaldehyde gas was introduced at 80~85 ℃, and then reacted at 80~85 ℃ for 1h. After the reaction, the material is poured into 200mL of cold water, and saturated sodium carbonate solution is added for alkaline hydrolysis to make the pH value reach 8~8.5. Let it stand and delaminate, separate the water layer, extract it with ether first, then acidify it with dilute sulfuric acid to a pH value of 1~2, and then extract it with ether. The ether layer is washed with 10% sodium carbonate and water. After drying and deether, the remaining white solid is salicylic alcohol, m.p.75 ~ 84 ℃, and the purity is 92%.
Salicylic alcohol can also be prepared by reacting phenol and formaldehyde aqueous solution under the catalysis of zinc acetate.
methoxythiophosphoryl dichloride was prepared by reacting 5mol methanol with 1mol of thion trichloride at 5~10 ℃ to prepare methoxythiophosphoryl dichloride with 90% yield.
synthesis of fruit and vegetable phosphorus 63.5g salicylic alcohol was dissolved in 192g 10% NaOH aqueous solution and filled in a dropping funnel. Then put 107g of O-methyl thiophosphoryl dichloride in the dropping funnel. Drop both into 500mL of water at the same time, keep the pH value of the reaction solution at 11~12 and the temperature at 15 ℃. After dropping, adjust the pH value of the reaction solution with 20% NaOH aqueous solution and maintain it at 11~12. After the reaction, let it stand, pour off the upper layer of water, dissolve the precipitate in about 1.5 times methanol, recrystallize, filter, vacuum dry to obtain yellow solid, namely fruit and vegetable phosphorus, m.p.51 ~ 55 ℃, purity 89.5%.
Fruit and vegetable phosphorus can also be prepared by reacting salicylaldehyde with methoxythiophosphoryl dichloride in alkali solution to obtain O-methyl-O-formyl phenyl thiophosphoryl chloride, and then reacted with borohydride in alkali solution. Operation process: dissolve 6.1g of salicylaldehyde, 8.3g of methoxythiophosphoryl dichloride and 80mL of methylbutylammonium bromide in 50mL of toluene, drop into 5.5g of sodium carbonate solution dissolved in 15mL of water at 5~10 ℃ under stirring, continue stirring reaction for 5h, add 50mL of water, separate liquid, wash toluene layer with water, dry, filter and concentrate to obtain oily O-methyl-O-form. Then 2.5g of thiophosphoryl chloride was dissolved in 10mL of toluene, cooled to 5~10 ℃, added into 10 mL0.2mol/L NaOH aqueous solution containing 0.5g of sodium borohydride under stirring, stirred for 2h, stirred for 16h at room temperature, separated and washed with water, the toluene layer was dried and filtered, toluene was evaporated, the residue was cooled, and recrystallized with methanol to obtain.
category
Pesticides
toxicity classification
High toxicity
acute toxicity
oral-rat LD50: 102 mg/kg; oral-mouse LD50: 88 mg/kg
flammability hazard characteristics
Decomposition of toxic phosphorus oxide and sulfur oxide gas by heating
storage and transportation features
The warehouse is ventilated and dry at low temperature; stored and transported separately from food raw materials
fire extinguishing agent
Sand, dry powder, foam
| WGK Germany | 3 |
| HazardClass | 6.1( B ) |
| PackingGroup | III |
| customs code | 29349990 |