Title: 2,4-D
CAS Registry Number: 94-75-7
CAS Name: (2,4-Dichlorophenoxy)acetic acid
Trademarks: Trinoxol (Crystal Chem.)
Molecular Formula: C8H6Cl2O3
Molecular Weight: 221.04
Percent Composition: C 43.47%, H 2.74%, Cl 32.08%, O 21.71%
Literature References: Prepd from 2,4-dichlorophenol and monochloroacetic acid in aq NaOH: Pokorny, J. Am. Chem. Soc. 63, 1768 (1941); Foster, GB 573476 (1945); by chlorination of molten phenoxyacetic acid: Manske, US 2471575 (1949 to U.S. Rubber); from 2,4-dichlorophenol, sodium, and ethyl chloroacetate followed by hydrolysis of the ester: Haskelberg, J. Org. Chem. 12, 426 (1947). Toxicology: V. K. Rowe, T. A. Hymas, Am. J. Vet. Res. 15, 622 (1954); J. M. Way, Residue Rev. 26, 37 (1969).
Properties: Crystals from benzene, mp 138°. bp0.4 160°. Almost insol in water. Sol in organic solvents. LD50 in mice, rats (mg/kg): 368, 375 orally (Rowe, Hymas).
Melting point: mp 138°
Boiling point: bp0.4 160°
Toxicity data: LD50 in mice, rats (mg/kg): 368, 375 orally (Rowe, Hymas)
Derivative Type: Sodium salt
Molecular Formula: C8H5Cl2NaO3
Molecular Weight: 243.02
Percent Composition: C 39.54%, H 2.07%, Cl 29.18%, Na 9.46%, O 19.75%
Properties: Needles from alc, dec 215°. Soly in water: 3.5%.
Derivative Type: Isopropyl ester
Trademarks: Esteron 44 (Dow)
Molecular Formula: C11H12Cl2O3
Molecular Weight: 263.12
Percent Composition: C 50.21%, H 4.60%, Cl 26.95%, O 18.24%
Properties: Liquid, d2525 1.255-1.270. Solidifies at +5°. Sol in oil.
Density: d2525 1.255-1.270
Derivative Type: Butyl ester
Trademarks: Lironox; Weedone (Nufarm)
Molecular Formula: C12H14Cl2O3
Molecular Weight: 277.14
Percent Composition: C 52.01%, H 5.09%, Cl 25.58%, O 17.32%
Literature References: Prepn: Nagel, DE 1144288 (1963 to Bayer), C.A. 59, 6315e (1963).
Derivative Type: Amine salts
Properties: Sol in water. The following amines form useful salts: Dimethylamine, isopropylamine, triethylamine, diethanolamine, triethanolamine. These salts are much more sol than the sodium salt. A small amount of sequestering agent, such as ethylenediaminetetraacetic acid, is generally added to prevent complex formation in hard water.
NOTE: The name Hedonal was formerly a synonym for carbamic acid 1-methylbutyl ester.
CAUTION: Potential symptoms of overexposure to 2,4-D are weakness, stupor, hyporeflexia and muscle twitch; convulsions; dermatitis. See NIOSH Pocket Guide to Chemical Hazards (DHHS/NIOSH 97-140, 1997) p 88.
Use: Herbicide. To increase latex output of old rubber trees. |