201. Alachlor

Nomenclature

CAS number: 15972-60-8
2-Chloro-N-(2,6-diethylphenyl)-N-(methoxymethyl)acetamide; 2-chloro-2′,6′-diethyl-N-(methoxymethyl)acetanilide; metachlor; CP-50144; Lasso (Monsanto); Alanex (Makhteshim-Agan).
C14H20ClNO2; mol wt 269.77.
C 62.33%, H 7.47%, Cl 13.14%, N 5.19%, O 11.86%.

Description and references

Pre-emergence herbicide. Prepn: NL 6602564 (1967 to Monsanto), C.A. 67, 99832r (1967). Activity: D. M. Evans, Chem. Ind. (London) 1969, 615. Soil degradn: R. S. Hargrove, M. G. Merkle, Weed Sci. 19, 652 (1971). Mechanism of action: L. M. Deal, F. D. Hess, ibid. 28, 168 (1980).

Chemical structure

Properties

Cryst solid, mp 40-41°. d2515.6 1.133. Soly in water at 23°: 140 mg/l. Sol in ether, acetone, benzene, ethanol, ethyl acetate. Hydrolyzed under strong acid or alkaline conditions. LD50 orally in rats: 1200 mg/kg (Evans).

Use

Herbicide.