GB994481A - Substituted n-phenyl-n-alkoxy-n-alkyl-ureas and a process for their manufacture - Google Patents

Abstract

The invention comprises compounds of formula <FORM:0994481/C2/1> wherein R1 is an alkyl radical having 1 to 4 carbon atoms, R2 is a saturated or unsaturated aliphatic radical having 1 to 12 carbon atoms which may be substituted by chlorine, n is 0, 1, 2 or 3 and m is 0 or 1, with the exception of compounds of the formula <FORM:0994481/C2/2> wherein R is CH3 or C2H5 and X represents 0 to 3 chlorine atoms and wherein a methyl group may be present in conjunction with a chlorine atom. The invention also comprises a process for the preparation of compounds of the first formula above wherein an amine of formula <FORM:0994481/C2/3> or a salt thereof is reacted with phosgene in an inert medium and the isocyanate is reacted without isolation with an O-alkyl-hydroxylamine R1-O-NH2 and the alkoxy urea obtained is alkylated with an alkylating agent in a mixture of an alkali metal hydroxide solution and alcohol. The compounds are used in herbicidal and acaricidal compositions (see Division A5). In an example a solution of phosgene in toluene is mixed with a solution of aniline in toluene, the mixture refluxed for 6 hours, the excess phosgene removed by a current of nitrogen, the mixture cooled, n-butoxyamine is added, the N-butoxyurea is filtered off, suspended in a mixture of methanol and aqueous sodium hydroxide and treated with dimethyl sulphate to yield N-phenyl-N1-n - butoxy - N1 - methyl - urea. The preparation of N - (3 - or 4 - chloro - or 3,4 - dichloro-or 2,4,5 - trichloro - phenyl) - N1 - methyl - N1-methoxyurea, N - (2 - methyl - 4 - chlorophenyl) N1 - methoxy - N1 - methyl - or - n - butylurea, N - (4 - chlorophenyl) - N1 - ethyl - or - isopropyl - or - n - butyl - or - 1 - or 2 methylpropyl- or -3-methylbutyl- or -allyl- or 3,3-dichloroallyl- or -dodecyl-N1-methoxyurea, N - phenyl - N1 - methyl - or - ethyl - or - n-butyl - N1 - methoxyurea, N - (2 - chloro - or - 2,4 - dichloro - or - 2,4,5 - trichlorophenyl) -N1 - n - butyl - N1 - methoxyurea and N - (4-methylphenyl) - N1 - methoxy - N1 - n - butylurea is also described in examples. Reference has been directed by the Comptroller to Specification 852,422.ALSO:Herbicidal and acaricidal compositions containing as active ingredient a compound of formula <FORM:0994481/A5-A6/1> wherein R1 is a C1-C4 alkyl radical, R2 is a saturated or unsaturated aliphatic radical having 1-12 carbon atoms which may be chloro-substituted, n is 0, 1, 2 or 3 and m is 0 or 1 (see Division C2), together with a suitable carrier, are specified. Specified compositions are aqueous suspensions and a spray powder containing siliceous chalk, colloidal preservative and a wetting agent. In Examples 24-28 the use of the compositions in treating weeds in corn, beans and peas and spider mites in pinks is described. Reference has been directed by the Comptroller to Specification 852,422.