S-metolachlor
NOMENCLATURE
Common name S-metolachlor
IUPAC name A mixture of (aRS,1S)-2-chloro-6'-ethyl-N-(2-methoxy-1-methylethyl)aceto-o-toluidide and (aRS,1R)-2-chloro-6'-ethyl-N-(2-methoxy-1-methylethyl)aceto-o-toluidide in the proportion 80-100% to 20-0%
Chemical Abstracts name A mixture of (S)-2-chloro-N-(2-ethyl-6-methylphenyl)-N-(2-methoxy-1-methylethyl)acetamide and (R)-2-chloro-N-(2-ethyl-6-methylphenyl)-N-(2-methoxy-1-methylethyl)acetamide in the proportion 80-100% to 20-0%
CAS RN [87392-12-9] (S)- isomer; [178961-20-1] (R)- isomer
EEC no.
CONTROL OBJECT
Crop
Control object
PHYSICAL CHEMISTRY

Composition A mixture of isomers in the proportion 80-100% (S)- to 20-0% (R)- 

Mol. wt. 283.8 

M.f. C15H22ClNO2  

Form Clear yellow to brownish liquid, with an unspecific odour.  

M.p. -61.1 °C 

B.p. c. 334 °C/760 mmHg 

V.p. 3.7 mPa (25 °C) 

KOW logP = 3.05 (20 °C)  

S.g./density 1.117 (20 °C) 

Solubility In water 480 mg/l (25 °C) 

Stability Hydrolysis DT50 >200 d (pH 7-9, 20 °C). 

F.p. 190 °C (EEC A9)

APPLICATIONGS
Cell division inhibitor; more recent research suggests chloroacetamides may inhibit synthesis of very long chain fatty acids (J. Schmalfuss et al., Abstr. Meeting WSSA, Toronto, 40, 117-118, 2000; P. Böger, Abstr. III Int. Weed Control Congr., Brazil 2000). Maize tolerance of chloroacetamides is attributed to rapid detoxification by glutathione S-transferases. Biochemistry
Selective herbicide, absorbed predominantly by the hypocotyls and shoots; inhibits germination Mode of action
Control of annual grasses (Echinochloa, Digitaria, Setaria, Brachiaria, Panicum, and Cyperus) and some broad-leaved weeds (Amaranthus, Capsella, Portulaca) in maize, sorghum, cotton, sugar beet, fodder beet, sugar cane, potatoes, soya beans, peanuts, sunflowers, various vegetables, and pulse crops. Applied pre-plant incorporated, pre-emergence or early post-emergence, at 0.8-1.6 kg/ha. Often used in combination with broad-leaved herbicides, to extend spectrum of activity. Uses
PRODUCT INFORMATION
Standard of technical material
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Content
Loss of drying
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content
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Typical application rates