Name | Esfenvalerate |
Synonyms | Esfenvalerate Fenvalerate-U (S)-cyano(3-phenoxyphenyl)methyl (2S)-2-(4-chlorophenyl)-3-methylbutanoate (R)-cyano(3-phenoxyphenyl)methyl (2R)-2-(4-chlorophenyl)-3-methylbutanoate |
CAS | 66230-04-4 |
InChI | InChI=1/C25H22ClNO3/c1-17(2)24(18-11-13-20(26)14-12-18)25(28)30-23(16-27)19-7-6-10-22(15-19)29-21-8-4-3-5-9-21/h3-15,17,23-24H,1-2H3/t23-,24+/m1/s1 |
Molecular Formula | C25H22ClNO3 |
Molar Mass | 419.9 |
Density | 1.21g/cm3 |
Melting Point | 59℃ |
Boling Point | 538.9°C at 760 mmHg |
Flash Point | 279.7°C |
Water Solubility | 0.002 mg l-1 (25 °C) |
Vapor Presure | 1.11E-11mmHg at 25°C |
Appearance | morphology neat |
Storage Condition | 0-6°C |
Refractive Index | 1.586 |
Physical and Chemical Properties | The pure chemical product is white crystalline solid, m.p.59 ~ 60.2 ℃; Relative density 1.26(26 ℃), vapor pressure 0.067 × 10-3Pa (25 ℃), refractive index n25D1.5787, optical rotation [α]25D-15.0 o. Soluble in organic solvents such as acetone, acetonitrile, chloroform, ethyl acetate, dimethylformamide, dimethyl sulfoxide, xylene, etc., solubility> 60%, solubility in methanol 7% ~ 10%, ethane 1%-5%; Solubility in water 0.3mg/L. Distribution coefficient (n-octanol/water) 1660000(25 ℃). It is stable in acidic medium, decomposed in alkaline medium, stable for 2 years at room temperature, and relatively stable for sunlight. The original drug is a brown viscous liquid, solid at room temperature, m.p.49.5 ~ 55.7 ℃. |
Use | Pyrethroid insecticides, can effectively control cotton, fruit trees, vegetables and other crops of pests |
Hazard Symbols | T - Toxic N - Dangerous for the environment |
Risk Codes | R23/25 - Toxic by inhalation and if swallowed. R43 - May cause sensitization by skin contact R50/53 - Very toxic to aquatic organisms, may cause long-term adverse effects in the aquatic environment. |
Safety Description | S24 - Avoid contact with skin. S36/37/39 - Wear suitable protective clothing, gloves and eye/face protection. S45 - In case of accident or if you feel unwell, seek medical advice immediately (show the label whenever possible.) S60 - This material and its container must be disposed of as hazardous waste. S61 - Avoid release to the environment. Refer to special instructions / safety data sheets. |
UN IDs | UN 2811 |
WGK Germany | 3 |
RTECS | CY1576367 |
HS Code | 29269090 |
Hazard Class | 6.1(b) |
Packing Group | III |
Toxicity | LC50 (96-hour) for fathead minnows 0.69 mg/L (Worthing and Hance, 1991); acute oral LD50 for rats 75 mg/kg (Hartley and Kidd, 1987). |
specific rotation | D25 -15.0° (c = 2.0 in CH3OH) |
BRN | 4275674 |
NIST chemical information | Benzeneacetic acid, 4-chloro-«alpha»-(1-methylethyl)-, cyano (3-phenoxyphenyl)methyl ester,(s-(r*,r*))-(66230-04-4) |
EPA chemical information | Esfenvalerate (66230-04-4) |
Toxicity
acute oral LD50 of rats is 87~325mg/kg, acute percutaneous LD50>5000mg/kg, acute inhalation of LC50480mg/kg (male) and 570mg/kg (female) of rats. It has mild irritation to rabbit eyes. The subacute oral no-effect dose in rats was 150mg/kg. No carcinogenic and reproductive toxicity was found in animal tests. Carp LC50690mg/L (96h). Toxic to aquatic animals.
biological activity
Esfenvalerate is one of the four isomers of pyrethroid insecticide fenvalerate.
in vivo studies
Esfenvalerate (0.1, 1, 7.5 or 15 mg/kg/day; gavage; from gestation day (GD) 13 to 19) shows clinical signs of neurotoxicity with 15 mg/kg/day.
production method
There are 2 asymmetric carbon atoms in the fenvalerate molecule, so there are four optical isomers of S,S,S,R,R,S,R,R. Among them, S,S body has the highest efficacy, R,R body has the lowest efficacy. The main methods to improve S,S body are as follows.
using chiral phase transfer catalyst to synthesize (S)-(-)-α methylbenzylamine as the resolution agent, the racemate α-isopropyl p-chlorophenylacetic acid is resolved to obtain S body acid, and then the corresponding S-acid chloride is synthesized. Then, it interacts with m-phenoxybenzaldehyde and sodium cyanide, and uses chiral N-benzyloccinkonidine ammonium chloride (BCDC) as a phase transfer catalyst to obtain diastereomers S,S and S,R bodies, of which S and S bodies are 5% excess. This method is a promising asymmetric synthesis method with simple operation, mild reaction conditions and high yield. The selection of chiral phase transfer catalysts and reaction conditions for this method need to be explored.
Chemical resolution-epimers First, α-isopropyl p-chlorophenylacetic acid is chemically resolved to make S-acid, and after acyl chlorination, it interacts with m-phenoxybenzaldehyde and sodium cyanide to make fenvalerate S,S body and S,R body. Then use their different physical and chemical properties to separate them. Finally, the S,R body epimers are made into S,S body. S,S body is cis-cyanophanic acid.
This method has been industrialized in Japan. The advantages are high purity, good quality and high yield of S and S. The disadvantages are that the use of R acid needs to be developed and the cost is relatively high.
The differential isomerization method uses the difference in the physical and chemical properties of the body (S,R and R,S enantiomer) and the β body (S,S and R,R enantiomer) to separate them. The body isomer is then turned into a β body. This method has low investment, simple operation and mild reaction conditions. It is a promising process route and has been tested in industrialization.
category
Pesticides
toxicity classification
High toxicity
acute toxicity
oral-rat LD50: 70.2 mg/kg; oral-mouse LD50: 185 mg/kg
flammability hazard characteristics
Flammable; combustion produces toxic nitrogen oxides and chloride gases
storage and transportation features
The warehouse is ventilated and dry at low temperature; stored and transported separately from food raw materials
fire extinguishing agent
Dry powder, foam, sand
toxic substance data | 66230-04-4(Hazardous Substances Data) |