Common name: Pretilachlor

Other name: pretilachlor (BSI, E- ISO); pretilachlore ((m) F-ISO)

Iupac name: 2-chloro-2`,6`-diethyl-N-(2-propoxyethyl)acetanilide

Chemical abstracts name:     2-chloro-N-(2,6- diethylphenyt)-N-(2-propoxyethyl)acetamide

Type: Herbicide

CAS RN: [51218 49 6]

M.F.: C₁₇H₂₆ClNO₂

Mol Wt: 311.9

 

Form (appearance): Colourless liquid.

B.P.: 135℃/0.001 mmHg

V.P.: 0.133 mPa (20℃)

F.P.: 129℃ (EEC A.9)

S.G.: 1.076 (20℃)

Solubility.: In water 50 mg/l (20℃). Very soluble in benzene, hexane, methanol and dichloromethane.

Stability: Relatively stable to hydrolysis; DT₅₀ (catc.) (20℃) >200 d (pH 1-9), 14 d (pH 13).

Henry: 8.1 × 10^-4 Pa m³ mol^-1

K_owlogP: 4.08 (shake flask)

 

Formulation types: EC; GR.

Biochemistry: Cell division inhibitor.

Mode of action: Selective herbicide. It is taken up readily by the hypocotyls, mesocotyls and coleoptites, and, to a lesser extent, by the roots of germinating weeds.

Uses: Herbicide effective against main annual grasses, broad leaved weeds and sedges in transplanted and seeded rice, at 1-1.25 kg/ha.

Phytotoxicity: Applied alone, pretilachlor will cause iniury to direct-seeded rice.

 

Oral: Acute oral LD₅₀ for rats 6099 mg/kg.

Skin and eye: Acute percutaneous LD₅₀ for rats >3100 mg/kg. Moderate irritant to skin; non irritant to eyes (rabbits).

Inhalation: LC₅₀ (4 h) for rats >2.8 mg/l air.

Noel: (2 y) for rats 30, mice 300 ppm; (0.5 y) for dogs 300 ppm.

ADI: 0.018 mg/kg.

Toxicity: WHO (a.i.) 111 (Table 5)

EC hazard: (R38, R43)

 

Birds: Non-toxic to birds; LD₅₀ for Japanese quail >10000 mg/kg. LC₅₀ for Japanese quail >1000 ppm.

Fish: LC₅₀ (96 h) for rainbow trout 0.9, catfish 2.7, crucian carp 2.3 mg/l.

Daphnia: LC₅₀ 13 mg/l.

Algae: EC₅₀ for Selenastrum capricornutum 0.002 mg/l.

Worms: Bees LD₅₀ (contact) 93 μg/bee.

 

Plant: Substitution of the chlorine atom to form a conjugate. Cleavage of the ether bond to yield an ethyl alcohol derivative. Hydrolytic and reductive removal of the chlorine atom.

Animals: Substitution of the chlorine atom for glutathione to form a conjugate. Cleavage of the ether bond to yield an ethyl alcohol derivative. Both metabolites are susceptible to further degradation.