13-05966. Methacrifos [Archived]

Nomenclature

CAS number: 62610-77-9
(2E)-3-[(Dimethoxyphosphinothioyl)oxy]-2-methyl-2-propenoic acid methyl ester; 3-hydroxy-2-methylacrylic acid methyl ester, O-ester with O,O-dimethyl phosphothioate; methyl (E)-3-(dimethoxyphosphinothioyloxy)-2-methylacrylate; CGA-20168; Damfin (Ciba-Geigy).
C7H13O5PS; mol wt 240.21.
C 35.00%, H 5.45%, O 33.30%, P 12.89%, S 13.35%.

Description and references

Organophosphorus insecticide effective against arthropod pests in stored grains. Prepn: E. Beriger, L. Pinter, ZA 6704184; eidem, US 3594454 (1967, 1971 both to Ciba); eidem, BE 766000; eidem, US 3923932 (1971, 1975 both to Ciba-Geigy). GLC determn of residues in stored grain: J. Desmarchelier et al., Pestic. Sci. 8, 473 (1977). Efficacy and long-term stability: R. L. Kirkpatrick et al., J. Econ. Entomol. 75, 277 (1982). Comparative field trial in stored sorghum: M. Bongston et al., Pestic. Sci. 14, 385 (1983). Comprehensive description: R. Wyniger et al., Proc. Br. Crop Prot. Conf. - Pests Dis. 1977, 1033.

Chemical structure

Properties

Oil, bp0.01 90°. Vapor pressure (20°): 8.3 × 104 mm Hg. Soly in water (20°): ≈400 ppm. Readily sol in many organic solvents. Highly toxic to rainbow trout. LD50 in rats (mg/kg): 678 orally; >3100 dermally (Wyniger).

Use

Grain protectant, insecticide, acaricide.

Status

This monograph has been retired and is no longer subject to revision or update.