Patent GB-965313-A (GB)
Title: Process for the manufacture of urea derivatives and pest-combating preparations containing them
IPC: C07C275/38
Filed: 1962-05-07
Abstract: Urea derivatives of the formula: <FORM:0965313/C1/1> in which R1 is hydrogen, an alkyl or alkoxy group of 1-4 carbon atoms or a halogen atom, R2 is hydrogen or an alkyl or alkoxy group of 1-4 carbon atoms, R3 is an alkyl group of 1-4 carbon atoms, or R2 and R3 form a heterocyclic ring with the adjacent nitrogen atom, are prepared by brominating the corresponding unbrominated compounds. The bromination may be effected with bromine itself or with a reagent which yields bromine, e.g. hypobromous acid or a salt thereof, such as sodium or calcium hypobromite, an N-bromo-carboxylic acid amide or imide, such as N-bromosuccinimide, and adducts of organic compounds and bromine, such as pyridine dibromide. The reaction may be effected at 60-100 DEG C. in a solvent, e.g. glacial acetic acid, chloroform, carbon tetrachloride, nitrobenzene, sulphuric acid, water or pyridine. Examples are given of the preparation of N-4-bromophenyl-N1, N1-dimethyl urea, N-4-bromophenyl-N1-methyl urea, N-4-bromo-3-chlorophenyl-N1, N1-dimethyl urea, N-4-bromo-3-methylphenyl-N1, N1-dimethyl urea, N-4-bromophenyl -N1-methyl-N1-methoxy urea, N-4-bromo-3-chlorophenyl-N1 - methyl - N1-methoxy urea N-4-bromo-3-chlorophenyl-N1-methyl urea, N-4-bromo-3-chlorophenyl-N1-methyl-N1-butyl urea, N-4-bromo-3-chlorophenyl urea N1-morpholide and N-4-bromo-3-methylphenyl urea N1-morpholide, in each case by direct bromination.  Urea derivatives of the formula above are claimed as novel compounds, provided that, when R2 is a hydrogen atom or an alkyl group of 1-4 carbon atoms, R1 is an alkyl or alkoxy group of 1-4 carbon atoms or a chlorine atom. The novel compounds are useful as herbicides (see Division A5). Specific claims are made to N-3-chloro-4-bromophenyl-N1, N1-dimethyl urea, N-3-methyl-4-bromophenyl-N1, N1-dimethyl urea, N-4-bromophenyl-N1-methyl-N1-methoxy urea, N-3-chloro-4-bromophenyl-N1-methyl-N1-n-butyl urea and N-3-chloro-4-bromophenyl-N1-methyl urea.ALSO:As herbicides, use is made of urea derivatives of the formula <FORM:0965313/A5-A6/1> in which R1 is hydrogen, an alkyl or alkoxy group of 1-4 carbon atoms or a halogen atom, R2 is hydrogen or an alkyl or alkoxy group of 1-4 carbon atoms, R3 is an alkyl group of 1-4 carbon atoms, or R2 and R3 form a heterocyclic ring with the adjacent nitrogen atom, provided that when R2 is hydrogen or an alkyl group of 1-4 carbon atoms, R1 is an alkyl or alkoxy group of 1-4 carbon atoms or a chlorine atom (see Division C2).  Examples are given of N-4-bromophenyl-N1,N1-dimethyl urea, N-4-bromophenyl-N1-methyl urea, N-4-bromo-3-chlorophenyl-N1,N1-dimethyl urea, N-4-bromo-3 - methylphenyl - N1,N1 - dimethyl urea, N - 4-bromophenyl - N1 - methyl - N1 - methoxy urea, N - 4 - bromo - 3 - chlorophenyl - N1 - methyl - N1-methoxy urea, N-4-bromo-3-chlorophenyl-N1-methyl urea, N-4-bromo-3-chlorophenyl-N1-methyl-N1-butyl urea, N-4-bromo-3-chlorophenyl urea N1-morpholide and N-4-bromo-3-methylphenyl urea N1-morpholide.  The products may be used together with an inert carrier, a solvent, a diluent, an emulsifier, a dispersing agent, a wetting agent, an adhesive, a fertilizer, a fungicide, a bactericide, a nematocide, an insecticide or another herbicide.  Specified herbicides which may be used with the products of the invention are tri- and tetrasubstituted alkyl-aryl ureas, halogenated phenoxy-alkane carboxylic acids, halogenated benzoic acids, halogenated phenylacetic acids, halogenated fatty acids or their salts, esters or amides, herbicidal tertiary or quaternary amines, carbamates, thiol-carbamates, dithiocarbamates, symmetrical triazines. 2-Chlorobenzthiazole, 3-amino-1,2,4-triazole, maleic acid hydrazide, 3,5 - dimethyltetrahydro - 1,3,5-thiadiazine - 2 - thione, 11 - phenyl - 4 - amino-5-chloropyridazone-6, pentachlorophenol, dinitrocresol, butyl-dinitrophenol, naphthylphthalamic acid and methyl isothiocyanate.  Specified pest-combating agents are chlorinated hydrocarbons and phosphoric acid esters.  Solutions suitable for spraying may be prepared with the aid of mineral oil fractions boiling above 100 DEG  C., e.g. diesel oil or kerosene, or with coal-tar oils or animal or vegetable oils, or with hydrocarbons, e.g. alkylnaphthalenes or tetrahydronaphthalene, optionally in association with xylene mixtures, cyclohexanol, ketones or chlorinated hydrocarbons, e.g. tetrachlorethane, trichlorethylene or tri- or tetra-chlorobenzenes.  Preparations which can be diluted with water can be prepared with the use of non-ionic, anionic or cationic dispersing agents, examples of each of which are given. As solid carriers for making dusting powders use may be made of talcum, kaolin, bentonite, calcium carbonate or phosphate, carbon, cork meal or wood meal.  Fatty acids, resins, glue, casein or alginates may be included in the compositions.  Experimental results are given of the use of aqueous compositions comprising the products of some of the examples above and sulphite cellulose waste liquor.