Title: Picloram
CAS Registry Number: 1918-02-1
CAS Name: 4-Amino-3,5,6-trichloro-2-pyridinecarboxylic acid
Additional Names: 4-amino-3,5,6-trichloropicolinic acid
Trademarks: Pinene (Diachem); Tordon (Dow AgroSci.)
Molecular Formula: C6H3Cl3N2O2
Molecular Weight: 241.46
Percent Composition: C 29.85%, H 1.25%, Cl 44.05%, N 11.60%, O 13.25%
Literature References: Plant growth regulator. Prepn: H. Johnston, M. S. Tomita, BE 628487; eidem, US 3285925 (1963, 1966 both to Dow). Activity: J. W. Hamaker et al., Science 141, 363 (1963). Carcinogenicity study: M. D. Reuber, J. Toxicol. Environ. Health 7, 207 (1981). Review of properties and analytical methods: J. R. Ramsey, Anal. Methods Pestic. Plant Growth Regul. Food Addit. 5, 507-525 (1967); of toxicology and environmental fate: W. R. Mullison, Proc. West. Soc. Weed Sci. 38, 21-92 (1985).
Properties: White powder, mp 218-219° with decomp starting at 190°. Readily sublimes at 190° under 12 mm Hg. Vapor pressure at 45°: 1.07 ´ 10-6 mm Hg. pKa 4.1. Soly at 25° (ppm): acetone 19800; ethanol 10500; acetonitrile 1600; ethyl ether 1200; water 430; benzene 200; carbon disulfide 50. LD50 in rats, mice, rabbits, guinea pig, chickens, sheep, cattle (mg/kg): 8200, 2000-4000, 2000, 3000, 6000, >1000, >750 orally (Mullison).
Melting point: mp 218-219° with decomp starting at 190°
pKa: pKa 4.1
Toxicity data: LD50 in rats, mice, rabbits, guinea pig, chickens, sheep, cattle (mg/kg): 8200, 2000-4000, 2000, 3000, 6000, >1000, >750 orally (Mullison)
CAUTION: Potential symptoms of overexposure are irritation of eyes, skin, respiratory system; nausea. See NIOSH Pocket Guide to Chemical Hazards (DHHS/NIOSH 97-140, 1997) p 258.
Use: Herbicide. |