Product Description
4-Chlorophenoxyacetic Acid, commonly abbreviated as 4-CPA, CAS#122-88-3, molecular formula C₈H₇ClO₃, molecular weight 186.59, is a high-purity industrial grade product with a minimum active content of 99.0%. It appears as white to off-white crystalline powder or needle crystal, with a faint characteristic odor. It is slightly soluble in water, freely soluble in ethanol, acetone, benzene and other common organic solvents, with a measured density of 1.366 g/cm³ and a stable melting point ranging from 157–159 °C. HS code is 29189900. As a synthetic auxin-type plant growth regulator, it is also widely known as Tomatotone, fruit-setting agent or anti-drop element, delivering reliable performance in preventing flower and fruit drop, boosting fruit setting rate and promoting uniform fruit enlargement across tomato, eggplant, pepper and other solanaceous vegetable crops. It also serves as a critical intermediate for pharmaceutical synthesis and high-end electronic materials, with a 24-month shelf life under sealed, dry and cool storage conditions.
Chemical Properties
| Melting point | 157-159 °C |
| Boiling point | 266.91°C (rough estimate) |
| density | 1.3245 (rough estimate) |
| refractive index | 1.5250 (estimate) |
| storage temp. | Sealed in dry,Room Temperature |
| solubility | 957mg/l |
| form | crystalline |
| pka | pK1: 3.10 (25°C) |
| color | White to light beige |
| Water Solubility | 848mg/L(25 ºC) |
| BRN | 1211804 |
| LogP | 2.250 |
| CAS DataBase Reference | 122-88-3(CAS DataBase Reference) |
| NIST Chemistry Reference | 4-Chlorophenoxyacetic acid(122-88-3) |
| EPA Substance Registry System | 4-Chlorophenoxyacetic acid (122-88-3) |
Safety Information
| Hazard Codes | Xn,Xi |
| Risk Statements | 22-R22 |
| Safety Statements | 22-24/25 |
| RIDADR | 2811 |
| WGK Germany | 1 |
| RTECS | AG0175000 |
| F | 21 |
| TSCA | Yes |
| HazardClass | IRRITANT |
| HS Code | 29189090 |
| Hazardous Substances Data | 122-88-3(Hazardous Substances Data) |
| Toxicity | LD50 oral in rat: 850mg/kg |
Product Application
4-chlorophenoxyacetic acid (CAS# 122-88-3) is a high-purity phenyl-oxy synthetic compound with significant application value across agricultural production, fine chemical synthesis and multiple other industrial fields. In agriculture, it functions as a highly effective and multifunctional plant growth regulator with auxin-like activity, far more stable in field environments than natural endogenous indole acetic acid, less prone to rapid photodegradation and microbial decomposition. It promotes nutrient biosynthesis and targeted biotransfer within plants, effectively blocks the formation of abscission layers at flower and fruit stalks, making it widely used in cash crops such as tomatoes, grapes, cucumbers and other common vegetables. It can dramatically reduce physiological flower and fruit drop, boost fruit setting rate by over 30% under adverse low-temperature conditions, and induce the formation of seedless fruits, while also helping to accelerate fruit expansion, improve fruit uniformity and increase overall commercial yield. In addition to its agricultural uses, it also acts as a key intermediate for pharmaceutical synthesis and specialty chemical production, supporting downstream preparation of multiple high-value fine chemical products.
