GB821103A - Improvements in or relating to substituted phenyl ureas and herbicidal compositions - Google Patents

Abstract

The invention comprises substituted ureas represented by the formula <FORM:0821103/IV (a)/1> wherein R represents an alkyl group containing 2, 3 or 4 carbon atoms, i.e. an ethyl, propyl, isopropyl, n-butyl, sec.-butyl or tert.-butyl group. The above substituted ureas are obtained by the reaction of appropriately p-alkyl-substituted phenyl isocyanates with methylethanolamine, e.g. in an inert liquid reaction medium such as xylene, toluene or dioxane. In examples: 3 - (p - cumenyl) - 1 - (2 - hydroxyethyl) - 1 - methylurea is obtained by heating p-cumidine with phosgene in xylene solution to reflux temperature until revolution of hydrogen chloride ceases, adding methylethanolamine to the cooled solution and heating and cooling the mixture (I); and other compounds of the above general formula wherein R is ethyl, n-propyl, isobutyl, sec.-butyl and tert.-butyl are similarly prepared (III, V, VII, IX and XI). White solids separate when the isocyanate solutions are first mixed with the methylethanolamine. The substituted ureas are employed in herbicidal compositions (see Group VI).ALSO:A herbicidal composition comprises one or more compounds of the general formula <FORM:0821103/VI/1> wherein R represents an alkyl group containing 2, 3 or 4 carbon atoms (see Group IV (b)) together with a carrier or diluent, said compound or compounds being present in the said composition in an amount sufficient to exert a herbicidal effect. Carriers mentioned include finely-divided solids such as talcs, clays, pyrophyllite, diatomaceous earth and walnut shell, wheat, redwood, soya bean, and cottonseed flours, and liquids, e.g. alkylated naphthalenes and cresols. The ureas may also be employed as dispersions, e.g. in oil and water, and surface-active agents may be included in the powder or liquid compositions. The surface-active agents may be of the anionic, cationic or nonionic types and include sodium and potassium oleates, amine salts of oleic acid such as morpholine and dimethylamine oleates, sulphonated animal and vegetable oils such as sulphonated fish and castor oils, sulphonated petroleum oils, sulphonated acyclic hydrocarbons, the sodium salt of lignosulphonic acid and other surface-active agents listed in "Soap and Sanitary Chemicals" August, September and October, 1949. Fertilizers, other herbicidal agents, insecticides and fungicides may also be included in the compositions. In examples: a powder suitable for dispersion in water for spraying comprises 3-(p-cumenyl) - 1 - (2 - hydroxyethyl) - 1 - methylurea, fuller's earth, sodium lauryl sulphate and methyl cellulose (II); a dusting powder comprises 3-(p-ethylphenyl)-1-(2-hydroxyethyl)-1-methylurea and talc (IV); a powder for spraying in oil, water or a mixture of oil and water comprises 1-(2-hydroxyethyl)-1-methyl-3-(p-n-propylphenyl)-urea, an alkylated aryl polyether alcohol and fuller's earth is dispersed in alkylated naphthalene oil (VI); a composition comprising 3-(p-isobutyl-phenyl)-1-(2-hydroxyethyl)-1-methylurea, a long-chain fatty alcohol sulphate, the sodium salt of lignosulphonic acid and kerosene is dispersed in water (VIII); pellets are prepared from an aqueous mixture of 3 - (p - sec. - butylphenyl) - 1 - (2 - hydroxyethyl) - 1 - methylurea sodium sulphate, the sodium salt of isopropyl naphthalene sulphonate and bentonite (X); and a dusting powder comprises 3 - (p - tert. - butylphenyl) - 1 - (2 - hydroxyethyl)-1-methylurea, cottonseed oil and walnut shell flour.