1837. Carfentrazone-ethyl

Nomenclature

CAS number: 128639-02-1
α-2-Dichloro-5-[4-(difluoromethyl)-4,5-dihydro-3-methyl-5-oxo-1H-1,2,4-triazol-1-yl]-4-fluorobenzenepropanoic acid ethyl ester; ethyl 2-chloro-3-[2-chloro-4-fluoro-5-(4-difluoromethyl-4,5-dihydro-3-methyl-5-oxo-1H-1,2,4-triazol-1-yl)phenyl]propionate; F8426; Aurora (FMC).
C15H14Cl2F3N3O3; mol wt 412.19.
C 43.71%, H 3.42%, Cl 17.20%, F 13.83%, N 10.19%, O 11.64%.

Description and references

Cereal herbicide that disrupts membranes by inhibiton of protoporphyrinogen oxidase. Prepn: K. M. Poss, WO 9002120 (1990 to FMC). Properties: W. A. Van Saun et al., Brighton Crop Prot. Conf. - Weeds 1993, 19. Synthesis and structure-activity: G. Theodoridis et al., ACS Symp. Ser. 584, 90 (1995). Mode of action: F. E. Dayan et al., Pestic. Sci. 51, 65 (1997). Control of broadleaf weeds in maize: S. F. Tutt et al., Brighton Crop Prot. Conf. - Weeds 1995 731; in wheat and barley: S. W. Shires et al., ibid. 1997, 117.

Chemical structure

Properties

Viscous yellow liquid, mp -22.1°. bp 760 350-355°. d20 1.457 g/cm3. Flash point: >110°C. log P (octanol/water): 3.36. Soly in water (μg/ml): 12 (20°); 22 (25°); 23 (30°). Vapor pressure at 25°: 1.2 × 10-7mm Hg; at 20°: 5.4 × 10-8mm Hg. LD50 in rats (mg/kg): 5143 orally (female); >4000 dermally (Van Saun).

Use

Post-emergent herbicide.