3957. Fenamiphos

Nomenclature

CAS number: 22224-92-6
N-(1-Methylethyl)phosphoramidic acid ethyl 3-methyl-4-(methylthio)phenyl ester; isopropylphosphoramidic acid ethyl 4-(methylthio)-m-tolyl ester; ethyl 4-(methylthio)-m-tolyl isopropylphosphoramidate; ethyl 3-methyl-4-(methylthio)phenyl (1-methylethyl)phosphoramidate; phenamiphos; Bay 68138; SRA-3886; B-68138; Bayer 68138; Nemacur (Bayer CropSci.).
C13H22NO3PS; mol wt 303.36.
C 51.47%, H 7.31%, N 4.62%, O 15.82%, P 10.21%, S 10.57%.

Description and references

Organophosphate insecticide; cholinesterase inhibitor. Prepn: H. Kayser, G. Schrader, US 2978479 (1961 to Bayer). Properties and nematocidal activity: B. Homeyer, Pflanzenschutz-Nachr. 24, 48 (1971). Field trials: W. M. Zeck, ibid. 24, 114 (1971). Degradation in soil: T. B. Waggoner, A. M. Khasawinah, Residue Rev. 53, 79 (1974). Microbial degradation study: T. P. Cáceres et al., Curr. Microbiol. 57, 643 (2008) DOI PubMed. Multiresidue determn by GC-MS: R. M. González-Rodríguez et al., J. Chromatogr. A 1196-1197, 100 (2008) DOI PubMed. Toxicity to birds: E. F. Hill, M. B. Camardese, Ecotoxicol. Environ. Saf. 8, 551 (1984) DOI PubMed.

Chemical structure

Properties

Crystals, mp 49°. d449 1.14°. Vapor pressure (30°): ≈1×10-6 mm Hg. Soly in water (20°): 700 ppm. Sol in most orgnic solvents. Poisonous. LD50 in male, female rats (mg/kg): 15.3, 19.4 orally (Homeyer).

Caution

Potential symptoms of overexposure are nausea, vomiting, abdominal cramps, diarrhea, salivation; headache, giddiness, vertigo, weakness; rhinorrhea, chest tightness; blurred vision, miosis; cardiac irregularities; muscle fasciculations; dyspnea. See NIOSH Pocket Guide to Chemical Hazards (DHHS/NIOSH 97-140, 1997) p 142.

Use

Nematocide.