Molecular Formula | C8H7ClO3 |
Molar Mass | 186.59 |
Density | 1.3245 (rough estimate) |
Melting Point | 157-159°C |
Boling Point | 266.91°C (rough estimate) |
Flash Point | 144.4°C |
Water Solubility | 848mg/L(25 ºC) |
Solubility | 957mg/l |
Vapor Presure | 0.000188mmHg at 25°C |
Appearance | White to bright light brown powder |
Color | White to light beige |
BRN | 1211804 |
pKa | pK1: 3.10 (25°C) |
Storage Condition | Sealed in dry,Room Temperature |
Refractive Index | 1.5250 (estimate) |
MDL | MFCD00004305 |
Physical and Chemical Properties | Melting point 157-159°C |
Use | Used as plant growth regulator, fruit drop prevention agent, herbicide, can be used for tomato flower thinning, peach fruit thinning |
Risk Codes | R22 - Harmful if swallowed |
Safety Description | S22 - Do not breathe dust. S24/25 - Avoid contact with skin and eyes. |
UN IDs | 2811 |
WGK Germany | 1 |
RTECS | AG0175000 |
FLUKA BRAND F CODES | 21 |
TSCA | Yes |
HS Code | 29189090 |
Hazard Class | IRRITANT |
Toxicity | LD50 oral in rat: 850mg/kg |
Raw Materials | P-Chlorophenol Chloroacetic acid |
NIST chemical information | Information provided by: webbook.nist.gov (external link) |
EPA chemical information | Information provided by: ofmpub.epa.gov (external link) |
overview | p-chlorophenoxyacetic acid is a systemic, efficient and multifunctional plant growth regulator, which can promote biosynthesis and biological transfer in plants. it can not only prevent falling flowers and fruits, improve fruit making rate, increase fruit growth rate, promote early ripening, but also achieve the purpose of improving plant quality. at the same time, it also has the effect of herbicide. Mainly used in tomatoes, grapes, vegetables, etc., can improve the yield and quality of crops, has great practical value. |
preparation | p-chlorophenoxyacetic acid is generated by reaction of phenoxyacetic acid, concentrated hydrochloric acid and 36.05% hydrogen peroxide under the catalysis of ferric chloride. The reaction equation is: 7.0g phenoxyacetic acid and 35mL glacial acetic acid are added to the reaction device equipped with electric stirrer, reflux condenser, thermometer, constant pressure funnel and 250mL four-mouth flask. Stir to dissolve phenoxyacetic acid. Weit 64mg ferric chloride and add it to a four-mouth flask, and slowly add 25mL concentrated hydrochloric acid dropwise. Heat the solution in the water bath to 65 ℃, and slowly add 15mL of 36.05% hydrogen peroxide dropwise. Since the reaction is exothermic, it is necessary to control the drip acceleration and keep the water bath temperature at 60~65 ℃. When the solution is reddish brown, the reaction is finished, cooling, crystallization, suction filtration and drying, and the crude yield of the product reaches 90%. Wash, recrystallize and weigh with ethanol: water = 1: 3 solution. |
uses | plant growth hormone, used as growth regulator, fruit drop preventive agent, herbicide, can be used in tomatoes, vegetables, peach trees, etc., and also used as pharmaceutical intermediates. Plant growth hormone, used as a growth regulator, fruit drop preventive agent, herbicide, and also used as a pharmaceutical intermediate. p-chlorophenoxyacetic acid can be used to synthesize a new type of hypoxia inducible factor -1 inhibitor. |
Production method | It is obtained by condensation of phenol and chloroacetic acid and chlorination. 1. Condensation Mixing melted phenol with 15% sodium hydroxide solution, neutralizing chloroacetic acid aqueous solution with sodium carbonate, putting the two into a reaction pot for mixing, heating and refluxing for 4 hours. After the reaction, add hydrochloric acid to adjust the pH to 2-3, stir and cool, crystallize, filter, wash with ice water, dry, and obtain phenoxyacetic acid. 2. Chlorination Mix phenoxyacetic acid and glacial acetic acid to dissolve, add iodine tablets, and pass chlorine at 26-34 ℃. After chlorination, leave it overnight, precipitate crystals in cold water the next day, filter, wash with water until neutral, and dry to obtain the finished product. |
category | pesticide |
toxicity classification | poisoning |
acute toxicity | oral administration-rat LD50: 850 mg/kg; Abdominal cavity-mouse LD50: 680 mg/kg |
flammability hazard characteristics | combustible; combustion produces toxic chloride 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 |
toxic substance data | information provided by: pubchem.ncbi.nlm.nih.gov (external link) |