Dimethachlor

Dimethachlor

二甲草胺

2-chloro-N-(2-methoxyethyl)acet-2′,6′-xylidide

2-chloro-N-(2,6-dimethylphenyl)-N-(2-methoxyethyl)acetamide

50563-36-5

C₁₃H₁₈ClNO₂

Herbicides > Anilide herbicides
Herbicides > Amide herbicides

Herbicide

Emulsifiable concentrate. Premix Parters: atrazine.

Molecular weight:255.7; Physical form:Colourless crystals. Density:1.23 (20 °C); Melting point:45.8-46.7 °C; Vapour pressure:1.5 mPa (25 °C); Henry constant:1.7×10-4 Pa m3 mol-1 ( calc.); Partition coefficient(n-octanol and water):logP = 2.17; Solubility:In water 2.3 g/l (25 °C). Readily soluble in most organic solvents, e.g. ketones, alcohols, chlorinated hydrocarbons, and aromatic hydrocarbons. In methanol, benzene, dichloromethane >800, n-octanol 440 (all in g/ kg, 25 °C).; Stability:Very stable in neutral media and in dilute acids. Hydrolysed in alkaline media ( pH 13). Readily soluble in most organic solvents, e.g. ketones, alcohols, chlorinated hydrocarbons, and aromatic hydrocarbons. In methanol, benzene, dichloromethane >800 g/kg, n-octanol 440 g/kg at 25°C.

Oral:Acute oral LD₅₀ for rats 1600->2000 mg/kg. Percutaneous:Acute percutaneous LD₅₀ for rats >3170 mg/kg. Slight irritant to skin and eyes of rabbits. Inhalation: LC₅₀ (4 h) for rats >4450 mg/m³. Phytotoxicity:Non-phytotoxic to oilseed rape. ADI:0.001 mg/kg.

Ecotoxicology: 
Algae: LC₅₀ (72 h) for Scenedesmus subspicatus 0.053 mg/l.Bees: LD₅₀ (oral and contact) >200 μg/bee.Birds: LC₅₀ for mallard ducks 200 ppm, Japanese quail 524 ppm. Dietary toxicity (8 d) for mallard ducks >10 000 ppm.Daphnia: LC₅₀ (48 h) 14.2-24 mg/l.Fish: LC₅₀ (96 h) for bluegill sunfish 15, rainbow trout 3.9, crucian carp 8 mg/l.Worms: LC₅₀ (14 d) 130 mg/kg. 
Environmental fate: 
Animals:The main metabolic reactions in rats are: O-dealkylation leading to O-desmethyl derivatives, substitution of the chlorine by a hydroxy group or by glutathione, reduction of the methylene chloride moiety giving rise to acetyl derivatives,Soil:Mean oc 63 ml/g. Slightly mobile in soil. In soil, 50 c. 4-15 d, DT₉₀ <100 d; dissipation is by the formation of bound residues, and in parallel reactions, by successive oxidatiPlant:Metabolism involves conjugation of the chloracetyl group, hydrolysis and sugar conjugation at the ether group, and formation of a heterocyclic ether-keto ring.
WATER SOLUBILITY: 2.3 g/l at 25°C.

Signal Word:CAUTION; Hazard Class:III (Slightly hazardous)