Ethephon

Identification

Synonyms: 2-chloroethylphosphonic acid (IUPAC);'Cerone' (Bayer CropScience); 'Ethrel' (Bayer CropScience); 'Sierra' (Bayer CropScience); 'Cerafon' (Hermoo); 'Eteroc' (Rocca); 'Sunthephon' (Sundat); 'Super Boll' (Nufarm Americas); mixtures 'Finish' (+ cyclanilide) (Bayer CropScience); 'CottonQuik' (+ urea sulfate) (Arysta LifeScience, DuPont, Nufarm Ltd); 'Terpal' (+ mepiquat chloride) (BASF, Bayer CropScience, DuPont). Other products 'Camposan' (Bayer CropScience); 'Charger' (Bayer CropScience); 'Etheverse' (Bayer CropScience); 'Florel' (Bayer CropScience); 'Prep' (Bayer CropScience); 'Tomathrel' (Bayer CropScience); 'Agritrel' (Cequisa); 'Boll Buster' (Loveland, UAP); 'Boll'd' (Winfield Solutions); 'Boost' (Vapco); 'Coolmore' (Barclay); 'Cybele' (Phyteurop); 'Eteplus' (Hermoo); 'Ethapon' (Plaaskem S.A.); 'Ethefix' (Hermoo); 'Ethefol' (Indofil); 'Etheplus' (Hermoo); 'Ethepro' (Protex); 'Ethio' (Agrochem); 'Flash' (Helena); 'Flordimex' (Cequisa); 'Galleon' (Nufarm Ltd); 'Halmstarker' (Stefes); 'Kripon' (Krishi Rasayan); 'Looping' (Arysta LifeScience EAME); 'Mature' (Fair); 'Phosgrow' (Sabero); 'Pilarfon' (Pilarquim); 'Ripex' (Jubilant Organosys); 'Setup' (Makhteshim-Agan)
CAS No.: 16672-87-0
EC No.: 240-718-3
Molecular Weight: 144.49
Molecular Formula: C2H6ClO3P
Structural Formula:
M.p.: 74 deg.C
B.p.: c. 265 °C (decomp.)
V.p.: <0.01 mPa (20 °C)
Kow: logP <–2.20 (25 °C, unstated pH)
Henry: <1.55 × 10-9 Pa m3 mol-1 (calc.)
S.g./density: 1.409±0.02 (20 °C) (tech.)
Solubility: In water 800 g/l (pH 4). Readily soluble in methanol, ethanol, isopropanol, acetone, diethyl ether and other polar organic solvents. Sparingly soluble in non-polar organic solvents such as benzene and toluene. Insoluble in kerosene and diesel oil.
Stability: Stable in aqueous solutions having pH <5; at higher pH, decomposition occurs with the liberation of ethylene; DT50 2.4 d (pH 7, 25 °C). Sensitive to uv irradiation.
pKa: pKa1 2.5, pKa2 7.2

Application

By metobolism-degradation, ethephone is converted into ethylene which can help the plant’s fruit to reach maturity more quickily. Ethephon is applied to promote pre-harvest ripening in apples, currants, blackberries, blueberries, cranberries, morello cherries, citrus fruit, figs, tomatoes, sugar beet and fodder beet seed crops, coffee, capsicums, etc.; to accelerate post-harvest ripening in bananas, mangoes and citrus fruit; to facilitate harvesting by loosening of the fruit in currants, gooseberries, cherries and apples; to increase flower bud development in young apple trees; to prevent lodging in cereals, maize and flax; to induce flowering of Bromeliads; to stimulate lateral branching in azaleas, geraniums and roses; to shorten the stem length in forced daffodils; to induce flowering and regulate ripening in pineapples; to accelerate boll opening in cotton; to modify sex expression in cucumbers and squash; to increase fruit setting and yield in cucumbers; to improve the sturdiness of onion seed crops; to hasten the yellowing of mature tobacco leaves; to stimulate latex flow in rubber trees, and resin flow in pine trees; to stimulate early uniform hull split in walnuts; etc. Maximum application rate per season 2.18 kg/ha for cotton, 0.72 kg/ha for cereals, 1.44 kg/ha for fruit.

Specification*

TC: 80%; 85%; 90%
SL: 480g/L(40%w/w); 720g/L; 70%(w/w)

Standard Packaging

Risks and Safety Information

Ethephone SL is corrosive Liquid, Hazard Class 8, UN 3265, PG III
Acute oral LD50 for rats 1564 mg/kg (tech.). Skin and eye Acute percutaneous LD50 for rabbits 1560 mg/kg (tech.). Irritating to skin and eyes. Birds Acute oral LD50 for bobwhite quail 1072 mg/kg (tech.). Dietary LC50 (8 d) for bobwhite quail >5000 ppm in diet (tech.). Fish LC50 (96 h) for carp >140, Daphnia EC50 (48 h) 1000 mg/l (tech.). Algae EC50 (24–48 h) for Chlorella vulgaris 32 mg/l.Bees Harmless to bees.