GB2033383A

GB2033383A - Herbicidally active carbamic acid phenyl esters and their manufacture and use

Info

Publication number: GB2033383A
Application number: GB7933946A
Authority: GB
Original assignee: Schering AG
Current assignee: Bayer Pharma AG
Priority date: 1978-10-12
Filing date: 1979-10-01
Publication date: 1980-05-21
Also published as: FR2438648B1; JPS5817744B2; FR2438648A1; ES484478A1; RO79322A; NL7906019A; AU5168479A; ZA795472B; DD146540A5; SE7908273L; MX5735E; AR223188A1; GR74033B; TR20602A; GB2033383B; EG13844A; FI792941A; CA1124251A; IT7926401A0; MA18607A1

Abstract

Novel carbamic acid phenyl esters have the formula I <IMAGE> (wherein R1 represents C1-C2 alkoxy- C1-C2-alkyl, di-C1-C2-alkoxy- C1-C2-alkoxy, CN-C1-C2-alkyl, Hal-C1-C2alkyl, HO-C1-C2-alkyl, phenyl-C1-C2-alkyl, 1,3-dioxolan-2- yl-methyl, 2-methyl-1,3-dioxolan-4- yl-methyl, 4-methyl-1,3-dioxolan-2- yl-methyl, 2,2-dimethyl-1,3-dioxolan- 4-yl-methyl or H2N-CO-C1-C2 alkyl, R2 represents phenyl optionally substituted by 1 or 2 substituents selected from Hal atoms and methyl and methoxy groups and R3 represents C1-C8-alkyl, C2-C8-alkenyl, cyclopropyl or Cl3C, or R1 represents methyl or ethyl, R2 represents alpha -CN- benzyl or 1-CN-2-phenylethyl and R3 represents ethyl). The compounds may be prepared from the appropriate 3-acylaminophenols or the chloroformates thereof. The novel compounds of the formula I have a herbicidal action and accordingly may be made up with suitable carriers into herbicidal preparations and may be used for protecting living plants and crop areas against weeds.

Description

SPECIFICATION Herbicidally active carbamic acid phenyl eskers afid lair bnanufacture and use The present invention is concerned with new cerbamic acid phenyl esters, with processes for the manufacture of these compounds and with their use as herbicidal agents.

Herbicidal 3-(carbamoyloxy)-anilides are already known (Belgian Patent Specification No.

686,239).

The problem upon which the present invention is based has been to provide new active substances having superior herbicidal properties.

This problem is solved in accordance with the present invention by the compounds of the general formula I, as defined below.

The present invention accordingly provides compounds of the general formula I

in which R, represents a C1-C2-alkoxy-C1-C2-alkyl, di-C1-C2-a lkoxy-C1-C2-alkyl, cya no-C1-C2-alkyl, halogeno-C1,-C2-alkyl, hydoxy-C1-C2-alkyl, phenyl-C1-C2-a Ikyl, 1 ,3-dioxolan-2-yl-methyl, 2 methyl ,3-dioxola n-4-yl-methyl, 4-methyl-l ,3-dioxola n-2-yI-methyl, 2,2-di methyl ,3-dioxolan 4-yl-methyl or aminocarbonyl-C,-C,-alkyl group, R2 represents an unsubstituted phenyl group or a phenyl group substituted by one or two substituents selected from halogen atoms, methyl groups and methoxy groups, and R3 represents a C1-C8-alkyl, C2-C8-alkenyl, cyclopropyl or trichloromethyl group, or R, represents a methyl or ethyl group, R2 represents an a-cyano-benzyl or i-cyano-2-phenyl-ethyl group, and R3 represents an ethyl group.

The compounds of the present invention are surprisingly superior in their herbicidal action to the known anilides of the kind mentioned above and therefore enrich the state of the art in this field.

The herbicidal action of these compounds extends to a great number of undesirable plant species, but not crop plants, towards which they possess an excellent selectivity spectrum.

The following are examples of species of plants that can be controlled very well: GRAMINEAE Festuca sp.,Alopecurus sp., Agrostis sp., Echinochloa, Setaria sp., Sorghum sp., Poa sp., Lolium sp., Arrhenaterum sp., Phalaris sp., Phleum sp., Eleusine sp., Bromus sp., Hordeum sp. and others.

CYPERACEAE Cyperus sp. and others.

LILIACEAE Allium sp. and others.

AMARANTHACEAE Amaranthus sp. and others.

BORAGINACEAE Anchusa sp., Amsinckia sp., Myosotis sp. and others.

CARYOPHYLACEAE Stellaria sp., Spergula sp., Cerastium sp. and others.

CHENOPODIACEAE Chenopodium sp., Salsola kail, Atriplex sp., Kochia sp. and others.

CONVOLVU LACEAE Ipomea sp. and others.

COMPOSITAE Ambrosia sp., Lactuca sp., Senecio sp., Xanthium sp., Gallnsoga sp., Centaurea sp., Matricaria sp., Halianthus sp., Chrysanthemum sp., Cichorium intybus and others.

CRUCIFERAE Brassica sp., Cheiranthus cheiri, Capsella sp., Thlaspi sp., Sinapis sp. and others.

EUPHORBIACEAE Euphorbia.

LABIATAE Lamium sp., Galeopsis sp. and others.

LEGUMINOSAE Medicago sp., Trifolium sp., Vicia sp., Cassia sp. and others.

MALVACEAE Abutilon theophrasti, Sida sp., Hibiscus sp., Anoda and others.

PAPAVERACEAE Papaversp., Escholtzia and others.

POLYGONACEAE Polygonum sp. and others.

PORTULACACEAE Portulaca sp. and others.

RUBIACEAE Galium sp., Richardia sp. and others.

RANUNCULACEAE Delphinium sp., Adonis sp. and others.

SCROPHULARIACEAE Linaria sp., Digitalis sp., Veronica sp. and others.

SOLANACEAE Datura sp., Solanum sp., Physalis sp. and others.

URTICACEAE Urtica sp. and others.

UMBELLIFERAE Daucus carota and others.

For the control of seed weeds, application quantities within the range of from 1 to 5 kg of active substance per hectare are generally used. The active substances can be used against these plant species according to the pre-emergence method and the post-emergence method. A particular advantage is that the compounds of the present invention display a specifically high tolerance in agricultural crops, especially in cotton, potato, rice, soya and sugar beet crops. When two or more compounds of the present invention are used the range of 1 to 5 kg refers of course to the total application quantities of these compounds.

The present invention accordingly also provides a herbicidal preparation which comprises a compound of the general formula I, in admixture or conjunction with a suitable carrier. The preparation may of course contain one or more compounds of the general formula The present invention further provides a method of protecting a living plant against weeds, wherein the area in the vicinity of the living plant is treated with a compound of the general formula The present invention further provides a method of protecting a crop area against weeds, wherein the crop area is treated with a compound of the general formula I.

The present invention further provides a pack which comprises a compound of the general formula I together with instructions for its use as a herbicide.

The compounds of the present invention may be used wither singly or in the form of mixtures with one another or with other active substances. If desired, other defoliants, plant protecting agents and/or Desticides may be added, depending on the desired purpose.

If a broadening of the spectrum of action is intended, other herbicides may also be added. As suitable herbicidally-active co-components there may be mentioned, for example, active substances from the groups of triazines, aminotriazoles, anilides, diazines, uracils, aliphatic carboxylic acids and halocarboxylic acids, substituted benzoic acids and aryloxycarboxylic acids, hydrazides, amides, nitriles, esters of such carboxylic acids, carbamic acid esters and thiocarbamic acid esters, ureas, 2,3,6trichlorobenzyloxypropanil, thiocyanogen-containing agents and other additives.

As other additives there may be used, for example, non-phytotoxic additives which, with herbicides, are capable of producing a synergistic increase in action, for example inter alia wetting agents, emulsifiers, solvents and oily additives.

The active compounds of the present invention or mixtures containing them are advantageously used in the form of herbicidal preparations, for example powders, strewable preparations, granules, solutions, emulsions or suspensions, with the addition of liquid and/or solid vehicles or diluents and, if desired, of surface-active agents, for example wetting, adhesive, emulsifying and/or dispersing agents.

Suitable liquid carriers are, for example, water, aliphatic hydrocarbons, aromatic hydrocarbons, for example benzene, toluene and xylene, cyclohexanone, isophorone, dimethyl sulphoxide, dimethylformamide and also mineral oil fractions.

Suitable solid carriers are, for example, mineral earths, for example tonsil, silica gel, talcum, kaolin, attaclay, limestone and silicic acid, and vegetable products, for example meals.

As surface-active agents there may be mentioned, for example, calcium lignin sulphonate, polyoxyethylenealkylphenol ethers, naphthalenesulphonic acids and salts thereof, phenolsulphonic acids and salts thereof, formaldehyde condensates, fatty alcohol sulphates and also substituted benzenesulphonic acids and salts thereof.

The proportion of the active substance or substances in the various herbicidal preparations may vary within wide limits. For example, the preparations may contain approximately 10 to 80% by weight of active substance(s), approximately 90 to 20% by weight of liquid or solid carrier and also, if desired, up to 20% by weight of surface-active agents).

The active compounds may be applied in the usual manner, for example with water as the carrier in quantities of spray liquor ranging from approximately 100 to 1000 litres per hectare. It is also possible to apply the active compounds by the so-called Low-Volume-Method and Ultra-Low-Volume Method as well as to apply them in the form of so-called microgranules.

The new compounds of the general formula I may be prepared, for example, by the processes of the present invention, as defined below.

The present invention accordingly further provides a process for the manufacture of the compounds of the general formula I, wherein a compound of the general formula Il

n which R3 has the meaning given above, is reacted in the presence of an organic base, for example pyridine, or is reacted in the form of an alkali salt thereof, for example a sodium or potassium salt, with a compound of the general formula III

in which R1 and R2 have the meanings given above.

The present invention further provides a process for the manufacture of the compounds of the general formula I, wherein a chloroformic acid ester of the general formula IV

in which R3 has the meaning given above, is reacted in the presence of a base, for example potassium carbonate, with a compound of the general formula V

in which R, and R2 have the meanings given above.

The products of these processes of the present invention may be isolated in a manner known per se.

The chloroformic acid ester of the general formula IV is advantageously prepared by reacting a compound of the general formula II with phosgene in the presence of an inorganic or organic base, for example sodium hydroxide or dimethylaniline, or by reacting an alkali salt of a compound of the general formula II with phosgene.

Suitable solvents for these reactions are, for example, ethyl actate, acetonitrile, hexane, benzene, toluene, methylene chloride, carbon tetrachloride, tetrahydrofuran, dimethylformamide and other substances that are inert towards the reactants.

All the reactions are carried out at temperatures of between 0 and the respective boiling point of the solvent.

The hydroxyanilides which may be used as starting materials are obtained in a manner known per se by reacting the corresponding acid chlorides with m-aminophenol.

The compounds of the present invention are colourless and odourless, crystalline or oily substances which are readily soluble in acetone, dimethylformamide, isophorone, cyclohexanone, tetrahydrofuran and dimethyl sulphoxide.

The following Examples illustrate the invention. Examples 1 to 5 illustrate the manufacture of the compounds od the present invention and Examples 6 and 7 illustrate the possible ways of using the compounds of the present invention and their superior herbicidal action.

EXAMPLE 1 N-(2,2-Diethoxyethyl)-carbanllic acid [3-(2,2-dimethylvalerylamino)-phenyl] ester A solution of 28.3 g (0.1 mole) of chloroformic acid 3-(2,2-dimethylvalerylamino)-phenyl ester in 100 ml of ethyl acetate and simultaneously a solution of 13.8 g (0.1 mole) of potassium carbonate in 70 ml of water were added dropwise to a solution of 20.9 g (0.1 mole) of N-(2,2-diethoxyethyl)-aniline in 50 ml of ethyl acetate, while stirring and cooling to 10 to 1 50C. Stirring was continued for 30 minutes at room temperature, the organic phase was then separated off, diluted with a little ethyl acetate, washed at OOC with dilute hydrochloric acid and a sodium chloride solution, and dried with magnesium sulphate, and the solvent was distilled off under reduced pressure.The residue was recrystallized from ethyl acetate/pentane.

Yield: 36 g = 79% of the theoretical yield.

M.p.: 88-890C.

EXAMPLE 2 N-/2-Cyanethyll-3-methylcarbanilic acid [3-(trichlorome thylcarbon ylamino)-phenyl] ester 31.7 g of chloroformic acid [3-(trichloromethylcarbonylamino)-phenyl] ester, taken up in 100 ml of acetonitrile, were added dropwise to a solution of 16.0 g of N-(2-cyanethyl)-3-methylaniline in 100 ml of acetonitrile. 12.1 g of N,N-dimethylaniline were then added to the reaction mixture. In so doing, the temperature rose to 460C. The reaction mixture was heated at the boil for a further 10 minutes, cooled, and stirred into 500 ml of ice-water, and the precipitated substance was filtered off and recrystallized from isopropanol.

Yield: 31.5 g = 72% of the theoretical yield.

M.p.: 11800.

EXAMPLE 3 n-Cyanomethylcarbanllic acid [3-(tert-butylcarbonylamino)-phenyl] ester 25.57 g of chloroformic acid [3-(tert-butylcarbonylamino)-phenyl] ester were introduced into a solution of 13.2 g of N-cyanomethylaniline in 1 50 ml of acetonitrile, then, while further stirring, 12.1 g of N,N-dimethylaniline were added dropwise, and the mixture was heated at the boil for a further 1 5 minutes. After having cooled, the mixture was stirred into 1 litre of ice-water, the substance that separated out was fiitered off with suction and, after drying in vacuo, recrystallized from a little acetonitrile.

Yield: 24.0 9 68% of the theoretical yield.

M.p.: 1730C.

EXAMPLE 4 N-/2-CyanethylJ-carbanilic acid [3-{cyclopropylcarbonylaminoJ-phenylV ester 29.2 g of N-(2-cyanethyl)-aniline were dissolved in 200 ml of acetonitrile, and 23.97 g of chloroformic acid [3-(cyclopropylcarbonylamino)-phenyl] ester were then added thereto, while stirring, during which the temperature of the solution rose to 350C. After leaving the mixture to stand overnight, the solvent was distilled off in vacuo, the oily residue remaining behind was treated with water, the water was decanted off and the oil was crystallized by means of a 1:1 mixture of isopropyl ether and isopropanol. The crystallizate was then recrystallized from isopropanol.

Yield: 1 6.59 g = 48% of the theoretical yield.

M.p.: 1420C.

EXAMPLE 5 N-Cyanomethyl-3-methylcarbanilic acid [3-(propion ylamino)-phen vll ester The potassium salt prepared from 64.4 g (0.39 mole) of propionic acid 3-hydroxyanilide was taken up in 300 ml of acetonitrile. Upon adding dropwise a solution of 81.4 g (0.39 mole) of N-cyanomethyl N-(3-methylphenyl)-carbamoyl chloride in 250 ml of acetonitrile, while stirring over a period of 5 minutes, the temperature rose from 28 to 440 C. The mixture was then refluxed for 30 minutes. After concentration by evaporation under reduced pressure, the mixture was dissolved in ethyl acetate and water, washed at OOC with a little dilute sodium hydroxide solution, dried with magnesium sulphate and concentrated by evaporation under reduced pressure.The residue, which was at first oily, crystallized from ether.

Yield: 80.4 g = 61% of the theoretical yield.

M.p.: 97-990C.

The following compounds of the present invention may be manufactured in a manner analogous to that described in any one of the above Examples.

Name of the compound Physical constant N-(2,2-Dimethoxyethyl)-carbanilic acid [3-(propionylamino)-phenyl] ester M.p.: 71- 730C N-Cyanomethylcarbanilic acid [3 (propionylamino)-phenyl] ester M.p.: 1300C N-(2-Cyanethyl)-4-methylcarbanilic acid [3-(propionylamino)-phenyl] ester M.p.: 149-151 0C N-(2-Methoxyethyl)-carbanilic acid [3-(propionylamino)-phenylj ester M.p.: 71- 720C N-(2-Cyanethyl)-4-methylcarbanilic acid [3-(propionylamino)-phenyl] ester M.p.: 124--1260C N-(2-Cyanethyl)-2-methylcarbanilic acid [3-(propionylamino)-phenyl] ester M.p.: 120-1220C N-(2-Methoxyethyl)-3-methylcarbanilic acid [3-(propionylamino)-phenyl] ester M.p.: : 82- 84oC N-(2,2-dimethoxyethyl)-4-methyl- carbanilic acid [3-(propionylamino) phenyl] ester n,20: 1.5343 N-(2,2-dimethoxyethyl)-3-methyl carbanilic acid [3-(propionylamino) phenyl] ester nD : 1.5405 N-(2-Bromethyl)-carbanilic acid [3 (propionylamino)-phenyl] ester M.p.: 86-670C N-(2-Ethoxyethyl)-carbanilic acid [3 (propionylamino)-phenyl] ester M.p.: 83-840C Name of the compound Physical constant N-(2-Cyanethyl)-carbanilic acid [3 (propionylamino)-phenylj ester M.p.: 126--1280C N-(2,2-Dimethoxyethyl-2-methyl- carbanilic acid [3-(propionylamino)phenyl] ester M.p.: 105-107 C N-( 1 -Cyano-2-phenyl-ethyl)N-methyl carbanilic acid [3-(propionylamino)phenyl] ester M.p.: 1040C N-(α-Cyanobenzyl)-N-ethyl-carbanilic acid [3-(propionyla mino)-phenyl] ester M.p.: 760C N-(2-Cyanethyl)-3-methylcarbanilic acid [3-(tert.-butylcarbonylamino)-phenyl] ester M.p.: 1220C N-(2-Cyanethyl)-carbanilic acid [3 (tert.-butylcarbonylamino)-phenyl] ester M.p.: 1180C N-( 1 ,3-Dioxolan-2-yl-methyl)- carbanilic acid [3-(propionylamino)phenyl] ester M.p.: 98-990C 3-methoxy-N-(2-methoxyethyl)carbanilic acid [3-(propionylamino)phenyl] ester n20D: 1.5614 N-(4-Methyl-1 ,3-dioxolan-2-yl-methyl)- carbanilic acid [3-(propionylamino)phenyl] ester nD : 1.5559 N-Cyanomethylcarbanilic acid [3 (2,2-dimethylvalerylamino)-phenyl] ester M.p.: 152-1530C N-(2-Cyanethyl)-carbanilic acid [3 (2,2-dimethylvalerylamino)-phenyl] ester M.p.: 93-950C N-(2-Cyanethyl)-carbanilic acid [3-(2methylpropionylamino)-phenyl] ester M.p.: 136-1 370C N-(2-Ch lorethyl)-carbanilic acid [3 (2,2-dimethylvalerylamino)-phenyl] ester M.p.: 101-102.50C N-(2-Chlorethyl)-'carbanilic acid [3 (propionylamino)-phenyl] ester M.p.: 107-1090C N-(2-Phenylethyl)-carbanilic acid [3 (propionylamino)-phenyl] ester M.p.:: 93-940C N-(2-Cyanethyl)-carbanilic acid [3 (crotonoylamino)-phenyl] ester M.p.: 117-1 190C N-(2-Chlorethyl)-carbanilic acid [3 (crotonoylamino)phenylj ester M.p.: 131-1 330C Name of the compound Physical constant N-(2,2-dimethoxyethyl)-carbanilic acid [3-(2,2-dimethylva lerylamino)-phenyl] ester M.p.: 77-790C N-(Aminocarbonylmethyl)-carbanilic acid [3-(cyclopropylcarbonylamino)phenyl] ester M.p.: 1970C N-(2-Aminocarbonylethyl)-carbanilic acid [3-(cyclopropylcarbonylamino)phenyl] ester M.p.: 1660C N-(2-Cyanethyl)-3-methylcarbanilic acid [3-(cyclopropylcarbonylamino)phenyl] ester M.p.: 1750C N-Cyanomethylcarbanilic acid [3 (trichloromethylcarbonylamino)phenyl] ester M.p.: 1020C N-(2-Cyanethyl)-carbanilic acid [3 (trichloromethylcarbonylamino)- phenyl] ester M.p.: 1370C N-(2-Methoxyethyl)-carbanilic acid [3 (tert.-butylcarbonylamino)-phenyl] ester nD : 1.5509 N-(2-Methoxyethyl)-3-methoxycarbanilic acid [3-(tert.-butylcarbonylamino)phenyl] ester nD : 1.5482 N-(2-Methoxyethyl)-carbanilic acid [3-(cyclopropylcarbonylamino)-phenyl] ester M.p.: 1330C N-(2-Methoxyethyl)-carbanilic acid [3 (trichloromethylcarbonylamino)-phenyl] ester n20: 1.5804 N-(2-Methoxyethyl)-3-methoxycarbanilic acid [3-(trichloromethylcarbonylamino)phenyl] ester M.p.: 1350C N-(2,2-Dimethyl-1 ,3-dioxolan-4-yl- methyl)-carbanilic acid [3-(2,2dimethylvaleryiamino)-phenyl] ester M.p.: 100--1020C N-(2-Ethoxyethyl)-carbanilic acid [3 (cyclopropylcarbonylamino)-phenyl] ester M.p.: 1090C N-Cyanomethyl-3-chlorocarbanilic acid [3-(trichloromethylcarbonylamino)- phenyl] ester M.p.: 1620C N-(2,2-Dimethoxyethyl)-3-methylcarbanilic acid [3-(tert.-butyl carbonyla mino)-phenyl] ester viscous oil N-(2-Hydroxyethyl)-carbanilic acid [3-(cyclopropylcarbonylamino)phenyl] ester M.p.: 116-1170C Name of the compound Physical constant N-(2-Methoxyethyl)-4-fluorocarbanilic acid [3-(cyclopropylcarbonylamino) phenyl] ester M.p.: 103-1050C N-(2-Ethoxyethyl)-4-fluorocarbanilic acid [3-(cyclopropylcarbonylamino) phenyl] ester M.p.: 77-790C The manufacture of a few starting materials is described in detail below.

a) 2,2-Dimethylvaleric acid 3-hydroxyanilide 455 g (3 moles) of 2,2-dimethylvaleric acid chloride were added dropwise, while stirring, and while the temperature was maintained at 1 0-200C by cooling, to a solution of 327 g (3 moles) of m aminophenol in approximately 1 litre of ethyl acetate after the addition of 400 ml of water and 76 g of magnesium oxide. The mixture was then stirred for one hour at room temperature. Then, at 50C, 400 ml of concentrated hydrochloric acid were added dropwise and the mixture was stirred for 10 minutes. The organic phase was then separated off, washed until neutral with a sodium chloride solution and dried with magnesium sulphate. The ethyl acetate was partially distilled off and pentane was added to the residue, whereupon the reaction product crystallized out.

Yield: 550 g = 83% of the theoretical yield.

M.p.: 155-1560C.

The following were obtained in an analogous manner: Propionic acid 3-hydroxyanilide M.p.: 183-1 850C 2-Methylpropionic acid 3-hydroxyanilide M.p.: 1 800C Crotonic acid 3-hydroxyanilide M.p.: 158-1 590C (b) Chloroformic acid [3-(propionylamino)-phenyl] ester 292 g (1.77 mole) of propionic acid 3-hydroxyanilide were added to a solution of 177 ml of phosgene in 700 ml of ethylacetate. A solution of 225 ml (1.77 mole) of N,N-dimethylaniline in 300 ml of ethyl acetate was then added dropwise, while stirring and cooling to 10 to 1 50C. Stirring was then continued for 30 minutes at 500C.The solution, cooled to 1 00C, was poured onto ice, and stirred for approximately 10 minutes, and the organic phase was separated off, washed with a sodium chloride solution, dried with magnesium sulphate and concentrated by evaporation under reduced pressure. The residue crystallized upon adding 600 ml of pentane.

Yield: 327 g = 81% of the theoretical yield.

M.p.: 72-730C.

The following were obtained in an analogous manner: Chloroformic acid [3-(2-methyl propionylamino)-phenyl] ester M.p.: 69-710C Chloroformic acid [3-(crotonoylamino) phenyl] ester nD20: 1.5327 Chloroformic acid [3-(2,2-dimethyl valer9ylamino)-phenyl] ester nD : 1.5273 c) Chloroformic acid [3-{cyclopropylcarbonylamino)-phenyq ester 100 ml of phosgene were condensed at 200 C, then taken up in 1 litre of ethyl acetate, and 177.2 g of cyclopropanecarboxylic acid 3-hydroxyanilide melting at 1 840C were added thereto, while stirring, at OOC. while continuing to cool the reaction mixture, 121 g of N,N-dimethylaniline were then added dropwise thereto. The mixture was then stirred for a further hour at 400 C, the excess phosgene was driven off by a stream of nitrogen gas, the mixture was cooled to room temperature and the ethyl acetate phase was extracted twice with 250 ml of ice water. After separating off the organic phase it was dried with magnesium sulphate, the solvent was distilled off in vacuo and the resulting residue was crystallized by adding petroleum ether. There was thus obtained 207 g (86% of the theoretical yield) of the above-mentioned substance melting at 940 C.

The following were prepared in an analogous manner: Chloroformic acid [3-(tert.-butylcarbonyl amino)-phenyl] ester M.p.: 750C Chloroformic acid [3-(trichl6rnmethyl- ~ carbonylamino)-phenyl] ester n020: 1.5786 EXAMPLE 6 In a series of tests carried out in a greenhouse, the compounds of the present invention listed in the Table below, were each sprayed in accordance with the post-emergence method at a rate of application of 5 kg of active substance per hectare, dissolved in 500 litres of water per hectare, on to Solanum and Brassica as the test plants.

3 Weeks after the treatment the results were evaluated and expressed by a numerical scale extending from 0 to 4, the value 0 representing no action and the value 4 representing destruction of the plant.

As will be seen from the Table, destruction of the test plants was generally achieved.

Compound of the invention Brassica Solanum N-(2,2-Dimethoxyethyl)-carbanilic acid [3-(propionylamino)-phenyl] ester 4 4 N-Cyanomethylcarbanilic acid [3 (propionylamino)-phenyl] ester 4 4 N-(2-Cyanethyl)-3-methylcarbanilic acid [3-(propionylamino)-phenyl] ester 4 4 N-(2-Methoxyethyl)-carbanilic acid [3-(propionylamino)-phenyl] ester 4 4 N-(2-Cyanethyl)-4-methylcarbanilic acid [3-(propionylamino)-phenyl] ester 4 4 N-(2-Cyanethyl)-2-methylcarbanilic acid [3-(propionylamino)-phenyl] ester 4 4 N-(2-Methoxyethyl)-3-methylcarbanilic acid [3-(propionylamino)-phenyl] ester 4 4 N -(2,2-Dimethoxyethyl)-4-methyl- carbanilic acid [3-(propionylamino) phenyl] ester 4 4 N- (2,2-Dimethoxyethyl)-3-methyl- carbanilic acid [3-(propionylamino) phenyl] ester 4 4 N-(2-Bromethyl)-carbanilic acid [3 (propionylamino)-phenyl] ester 4 4 N-(2-Ethoxyethyl)-carbanilic acid [3-(propionylamino)-phenyl] ester 4 4 N-(2-Cyanethyl)-carbanilic acid [3 (propionylamino)-phenyl] ester 4 4 N-(2,2-Dimethoxyethyl)-2-methyl- carbanilic acid [3-(propionylamino) phenyl] ester 4 4 Compound of the invention Brassica Solanum N-Cyanomethyl-3-methylcarbanilic acid [3-(propionylamino)-phenyl] ester 4 4 N-( 1 -Cyano-2-pheny-ethyl)-N-methylcarbamic acid [3-(propionylamino)phenyl] ester 4 4 N-(a-Cyano-benzyl)-N-ethyl-carbamic acid [3-(propionylamino)-phenyl] ester 4 4 N-(1 ,3-Dioxolan-2-yl-methyl)carbanilic acid [3-(propionylamino)phenyl] ester 4 4 3-Methoxy-N-(2-methoxyethyl)carbanilic acid [3-(propionylamino)phenyl] ester 4 4 N-(4-Methyl-1 ,3-dioxolan-2-yl-methyl)carbanilic acid [3-(ethylcarbonylamino)-phenyll ester 4 4 N-Cyanomethylcarbanilic acid [3 (2,2-dimethylvalerylamino)phenyl] ester 4 4 N-(2-Cyanethyl)-carbanilic acid [3 (2,2-dimethylvalerylamino)-phenyll ester 4 4 N-(2-Cyanethyl)-carbanilic acid [3 (2-methylpropionylamino)-phenyl] ester 4 4 N-(2,2-Diethoxyethyl)-carbanilic acid [3-(2,2-dimethylvalerylamino)- 4 4 phenyl] ester N-(2-Chlorethyl)-carbanilic acid [3 (2,2-dimethylvalerylamino)-phenyl] ester 4 4 N-(2-Chlorethyl)-carbanilic acid [3 (propionylamino)-phenyl] ester 4 4 N-(2-Phenylethyl)-carbanilic acid [3 (propionylamino)-phenyl] ester 4 4 N-(2-Cyanethyl)-carbanilic acid [3 (crotonoylamino)-phenyl] ester 4 4 N-(2-Chlorethyl)-carbanilic acid [3 (crotonoylamino)-phenyl] ester 4 4 N-(2,2-Dimethoxyethyl)-carbanilic acid [3-(2,2-dimethylva leryla mino)- phenyl] ester 4 4 Compound of the invention Brassica Solanum N-(2-Cyanethyl)-carbanilic acid J3- (cyclopropylcarbonylamino)-phenyl] ester N-Cyanomethylcarbanilic acid [3 (tert.-butylcarbonylamino)-phenyl] ester 4 4 N-(2-Cyanethyl)-3-methylcarbanilic acid [3-(tert.-butylca rbonylamino)phenyl] ester 4 4 N-(2-Cyanethyl)-carbanilic acid [3 (tert.-butylcarbonylamino)-phenyl] 4 4 ester N-Cyanomethylcarbanilic acid [3 (trichloromethylcarbonylamino)phenyl] ester 4 N-(2-Methoxyethyl)-carbanilic acid [3-(tert.-butylcarbonylamino)-phenyl] ester 4 4 N-(2-Methoxyethyl)-3methoxycarbanilic acid [3-(tert.butylcarbonylamino)-phenyl] ester 4 4 N-(2-Methoxyethyl)-carbanilic acid [3-(cyclopropylcarbonylam ino)- phenyl] ester 4 4 N-(2-Methoxyethyl)-carbanilic acid [3-(trichloromethylcarbonylamino)- phenyl] ester 4 4 N-(2-Methoxyethyl)-3methoxycarbanilic acid [3-(trichloromethylcarbonylamino)-phenyl] ester 4 4 N-(2-Ethoxyethyl)-carbanilic acid [3-(cyclopropylcarbonylamino)phenyl] ester 4 4 N-(2-Hydroxyethyl)-carbanilic acid [3-(cyclopropylcarbonylamino)phenyl] ester 4 4 N-(2-Methoxyethyl)-4fluorocarbanilic acid [3-(cyclopropylcarbonylamino)-phenyl] ester 4 4 N-(2-Ethoxyethyl)-4-fluorocarbanilic acid [3-(cyclopropylcarbonylamino)phenyl] ester 4 4 N-Cyanomethyl-3-chlorocarbanilic acid [3-(trichloromethylcarbonylamino)-phenyl] ester 4 4 Compound of the invention Brassica Solanum N-(2,2-Dimethoxyethyl)-3-methyl carbanilic acid [3-(tert.-butyl carbonylamino)-phenyl] ester 4 4 Untreated 0 0 EXAMPLE 7 In a series of tests carried out in a greenhouse, the plants listed in the Table below were treated after their emergence with the agents listed, using in each case an application quantity of 3 kg of active substance per hectare. For this purpose, the agents wherein each case sprayed uniformly over the plants in the form of an emulsion, using 500 litres of water per hectare. The results of the treatment were assessed and expressed by a numerical scale extending from 0 to 10, the value 0 representing total destruction of the plant and the value 10 representing no damage. In this case, 3 weeks after the treatment, the compounds of the present invention exhibited a high degree of selectivity together with an excellent action against the weeds. The agents used for comparison did not exhibit this selectivity.

a) a) a) a) 0 a) 0 0 a) 0 .

U a E O 8 L 0 F m a) % a) Compound of the invention coo L cJ co m N-(2-Cyanethyl)-3-methyl carbanilic acid [3-(propionyl amino)-phenyll ester - 10 10 10 10 0 0 0 0 0 0 0 N-(2-Methoxyethy I )-3-methyl carbanilic acid [3-(propionyl amino)-phenyl] ester 10 10 10 10 10 0 0 0 0 0 0 0 N-Cyanomethyl-3-methy I carbanilic acid [3-(propionyl amino)-phenyl]- ester 10 10 10 10 10 0 0 0 0 0 0 0 N-(a-Cyanobenzyl)-N-ethy I carbamic acid [3-(propionyl amino)-phenyl3 ester 10 10 10 10 10 0 0 0 0 0 0 0 N-(2-Chlorethyl)-carbani lic acid [3-(2,2-dimethyl val eryl amino)-phenyl] ester 10 10 10 10 10 0 0 0 0 0 0 0 a) Co a a) Agents for comparison 3 O c a) E X X É 0 a)0 . Co (according to Belgian Patent U U Co ~ eo Specification 0 686,239) a) Specification No. 686,239) : CLO o0 coO S s t co a n-Butylcarbamic acid [3 (propionylamino)-phenyl] ester 0 5 0 1 5 0 0 0 0 0 0 0 Isobutylcarbamic acid [3 (propionylamino)-phenyl] ester 0 8 0 1 8 0 0 0 0 0 - 0 0

Claims

1. A carbamic acid phenyl ester of the general formula I

in which R1 represents a C1-C2-a lkoxy-C1-C2-alkyl, di-C12-a lkoxy-C1-C2-alkyl, cya no-C1-C2-alkyl, halogeno-C1C2-alkyi, hydroxy-C,-C,-alkyl, phenyl-C1-C2-alkyl, 1 ,3-dioxolan-2-yl-methyl, 2- methyl-1 ,3-dioxola n-4-yl-methyl, 4-methyl-1 ,3-dioxolan-2-yI-methyl, 2 2-dimethyl- 1 3-dioxolan- 4-yl-methyl or aminocarbonyl-C,-C,-alkyl group, R2 represents an unsubstituted phenyl group or a phenyl group substituted by one or two substituents selected from halogen atoms, methyl groups and methoxy groups, and R3 represents a C1-C8-alkyl, C2-C8-alkenyl, cyclopropyl or trichloromethyl group, or R, represents a methyl or ethyl group, R2 represents an a-cyano-benzyl or 1-cyano-2-phenyl-ethyl group, and R3 represents an ethyl group.

2. N-(2,2-Diethoxyethyl)-carbanilic acid [3-(2,2-dimethylvaleryla mino)-phenyl] ester.

3. N-(2-Cyanethyl)-3-methylcarbanilic acid [3-(trichloromethylcarbonylamino)-phenyi] ester.

4. N-Cyanomethylcarbanilic acid [3-(tert.-butylcarbonylamino)-phenyl] ester.

5. N-(2-Cyanethyl)-ca rbanilic acid [3-(cyclopropylcarbonyla m ino)-phenyl] ester.

6. N-(2,2-Dimethoxyethyl)-carbanilic acid [3-(propionylamino)-phenyl] ester.

7. N-Cyanomethylcarbanilic acid [3-(propionylamino)-phenyl] ester.

8. N-(2-Cyanethyl)-3-methylcarbanilic acid [3-(propionylamino)-phenyl] ester.

9. N-(2-Methoxyethyl)-carbanilic acid [3-(propionylamino)-phenyl] ester.

10. N-(2-Cyanethyl)-4-methylcarbanilic acid [3-(propionyla mino)-phenyl] ester.

11. N-(2-Cyanethyl)-2-methylcarbanilic acid [3-(propionylamino)-phenyl] ester.

1 2. N-(2-Methoxyethyl)-3-methylcarbanilic acid [3-(propionylamino)-phenyl] ester.

1 3. N-(2,2-Dimethoxyethyl)-4-methylcarbanilic acid [3-(propionylamino)-phenyl] ester.

14. N-(2,2-Dimethoxyethyl)-3-methylca rban ilic acid [3-(propionylami no)-phenyl] ester.

1 5. N-(2-Bromethyl)-carbanilic acid [3-(propionylamino)-phenyl] ester.

1 6. N-(2-Ethoxyethyl)-carbanilic acid [3-(propionylamino)-phenyl] ester.

17. N-(2-Cyanethyl)-ca rbanilic acid [3-(propionyla mino)-phenyl] ester.

1 8. N-(2,2-Dimethoxyethyl)-2-methylcarbanilic acid [3-(propionylamino)-phenyl] ester.

1 9. N-Cyanomethyl-3-methylcarbanilic acid [3-(propionylamino)-phenyl] ester

20. N-( 1 -Cyano-2-phenyl-ethyl)-N-methyl-carbamic acid [3-(propionylamino)-phenyl] ester.

21. N-(a-Cyano-benzyl)-N-ethyl-carbamic acid [3-(propionylamino)-phenyl] ester.

22. N-(l ,3-Dioxolan-2-yi-methyl)-carbanilic acid [3-(propionylamino)-phenyl] ester.

23. 3-Methoxy-N-(2-methoxyethyl )-ca rbanilic acid [3-(propionylami no)-phenyl] ester.

24. N-(4-methyl-1 ,3-dioxolan-2-yl-methyl)-carbanilic acid [3-(propionyla mino)-phenyl] ester

25. N-Cyanomethyicarbanilic acid [3-(2,2-dimethylvalerylamino)-phenyl] ester.

26. N-(2-Cyanethyl)-carbanilic acid [3-(2,2-dimethylva leryla mino)-phenyl] ester.

27. N-(2-Cyanethyl)-carbanilic acid [3-(2-methylpropionylamino)-phenyl] ester.

28. N-(2-Chlorethyl)-ca rbanilic acid [3-(2 [3-(2,2-dimethylva leryla mino)-phenyl] ester.

29. N-(2-Chlorethyl)-carbanilic acid [3-(propionylamino)-phenyl] ester.

30. N-(2-Phenylethyl)-carbanilic acid [3-(propionylamino)-phenyl] ester.

31. N-(2-Cyanethyl)-carbanilic acid [3-(crotonoylamino)-phenyl] ester.

32. N-(2-Chlorethyl)-carbanilic acid [3-(crotonoylamino)-phenyl] ester.

33. N-(2,2-Dimethoxyethyl)-carbanilic acid [3-(2,2-dimethylvalerylamino)-phenyl] ester.

34. N-(Ami nocarbonylmethyl)-ca rbanilic acid [3-(cyclopropylcarbonylamino)-phenyl] ester.

35. N-(2-Ami noca rbonylethyl)-ca rbani lic acid [3-(cyclopropylcarbonylamino)-phenyl] ester.

36. N-(2-Cyanethyl)-3-methylcarbanilic acid [3-(cyclopropylcarbonylamino)-phenyl] ester.

37. N-(2-Cyanethyl)-3-methylcarba nilic acid [3-(tert.-butylcarbonylamino)-phenyl] ester.

38. N-(2-Cyanethyl)-carbanilic acid [3-(tert.-butyicarbonylamino)-phe nyl] ester.

39. N-Cyanomethylcarbanilic acid [3-(trichloromethylca rbonyla mino)-phenyl] ester.

40. N-(2-Cyanethyi)-carbanilic acid [3-(trichloromethylcarbonylamino)-phenyl] ester.

41. N-(2,2-Dimethyl-l ,3-dioxolan-4-yl-methyl)-carbanilic acid [3-(2,2-dimethylvalerylamino)- phenyl] ester.

42. N-(2-methoxyethyl)-carba n ilic acid [3-(tert.-butylca rbonyla mino)-phenyl] ester.

43. N-(2-Methoxyethyl)-3-methoxycarbe nilic acid [3-(tert.-butylcarbonylamino)-phenyl] ester.

44. N-(2-Methoxyethyl)-carbanilic acid [3-(cyclopropylcarbonylamino)-phenyl] ester.

45. N-(2-methoxyethyl)-carbanilic acid [3-(trichloromethylcarbonyla mino)-phenyl] ester.

46. N-(2-Methoxyethyl)-carbanilic acid [3-(trichloromethylcarbonylamino)-phenyl] ester.

47. N-(2-Ethoxyethyl)-carbanilic acid [3-(cyclopropylcarbonylamino)-phenyl] ester.

48. N-(2-Hydroxyethyl)-carba nilic acid [3-(cyclopropylcarbonyla mino)-phenyl] ester.

49. N-(2-Methoxyethyl)-4-fluorocarbanilic acid [3-(cyclopropylcarbonylamino)-phenyl] ester.

50. N-(2-Ethoxyethyl)-4-fluorocarbanilic acid [3-(cyclopropylcarbonylamino)-phenyl] ester.

51. N-Cyanomethyl-3-chlorocarbanilic acid [3-(trichloromethylcarbonylamino)-phenyl] ester.

52. N-(2,2-Dimethoxyethyl)-3-methylcarbanilic acid [3-(tert.-butylcarbonylamino)-phenyl] ester.

53. A process for the manufacture of a compound of the general formula I given in claim 1, in which Fl1, R2 and R3 have the meanings given in claim 1, wherein a compound of the general formula II

in which R3 has the meaning given in claim 1, is reacted in the presence of an organic base or is reacted in the form of an alkali salt thereof with a compound of the general formula III

in which R1 and R2 have the meanings given in claim 1.

54. A process as claimed in claim 53, conducted substantially as described herein.

55. A process for the manufacture of a compound of the general formula I given in claim 1, in which Fl1, R2 and R3 have the meanings given in claim 1, wherein a chloroformic acid ester of the general formula IV

in which R3 has the meaning given in claim 1, is reacted in the presence of a base with a compound of the general formula V

in which R, and R2 have the meanings given in claim 1.

56. A process as claimed in claim 55, wherein the chloroformic acid ester of the general formula IV has beeri prepared by the reaction of a compound of the general formula II given in claim 53, in which R3 has the meaning given in claim 1, in the presence of an inorganic or organic base with phosgene, or by the reaction of an alkali salt of such a compound of the general formula II with phosgene.

57. A process as claimed in claim 55, conducted substantially as described herein.

58. A process for the manufacture of a compound as claimed in claim 1, conducted substantially as described in any one of Examples 1 to 5 herein.

59. A herbicidal preparation which comprises a compound of the general formula I given in claim 1,in which R,, R2 and R3 have the meanings given in claim 1, in admixture or conjunction with a suitable carrier.

60. A herbicidal preparation which comprises the compound claimed in any one of claims 2 to 46, in admixture or conjunction with a suitable carrier.

61. A herbicidal preparation which comprises the compound claimed in any one of claims 47 to 52, in admixture or conjunction with a suitable carrier.

62. A preparation as claimed in any one of claims 59 to 61, which is in the form of a powder, a strewable preparation, granules, a solution, an emulsion or a suspension.

63. A preparation as claimed in any one of claims 59 to 62, containing a single compound of the general formula 1.

64. A preparation as claimed in any one of claims 59 to 62, containing two or more compounds of the general formula

65. A preparation as claimed in any one of claims 59 to 64, which also contains one or more active substances selected from defoliants, plant protecting agents, pesticides and herbicides other than compounds of the general formula I.

66. A preparation as claimed in any one of claims 59 to 65, wherein the total amount present of active substance or substances is approximately 10 to 80% by weight.

67. A preparation as claimed in any one of claims 59 to 66, containing a single surface-active agent in an amount of up to 20% by weight.

68. A preparation as claimed in any one of claims 59 to 66, containing two or more surface-active agents in a total amount of up to 20% by weight.

69. Any one of the herbicidal preparations as claimed in claim 59 and substantially as described in Example 6 herein.

70. Any one of the herbicidal preparations as claimed in claim 59 and substantially as described in Example 7 herein.

71. A method of protecting a living plant against weeds, wherein the area in the vicinity of the living plant is treated with a compound of the general formula I given in claim 1, in which R1, R2 and R3 have the meanings given in claim 1.

72. A method as claimed in claim 71, wherein the area is treated with the compound claimed in any one of claims 2 to 46.

73. A method as claimed in claim 71, wherein the area is treated with the compound claimed in any one of claims 47 to 52.

74. A method as claimed in claim 71, wherein the area is treated with a herbicidal preparation as claimed in any one of claims 59 to 70.

75. A method as claimed in any one of claims 71 to 74, wherein a single compound of the general formula I is used for the treatment in an amount within the range of from 1 to 5 kg per hectare.

76. A method as claimed in any one of claims 71 to 74, wherein two or more compounds of the general formula I are used for the treatment in a total amount within the range of from 1 to 5 kg per hectare.

77. A method as claimed in claim 71, conducted substantially as described in Example 7 herein.

78. A method of protecting a crop area against weeds, wherein the crop area is treated with a compound of the general formula I given in claim 1, in which Fl1, R2 and R3 have the meanings given in claim 1.

79. A method as claimed in claim 78, wherein the crqp area is treated with the compound claimed in any one of claims 2 to 46.

80. A method as claimed in claim 78, wherein the crop area is treated with the compound claimed in any one of claims 47 to 52.

81. A method as claimed in claim 78, wherein the crop area is treated with a herbicidal preparation as claimed in any one of claims 59 to 70.

82. A method as claimed in any one of claims 78 to 81, wherein a single compound of the general formula I is used for the treatment in an amount within the range of from 1 to 5 kg per hectare.

83. A method as claimed in any one of claims 78 to 81, wherein two or more compounds of the general formula I are used for the treatment in a total amount within the range of from 1 to 5 kg per hectare.

84. A method as claimed in any one of claims 78 to 83, wherein the crop is a cotton, potato, rice, soya or sugar beet crop.

85. A pack which comprises a compound of the general formula I given in claim 1, in which Fl1, R2 and R3 have the meanings given in claim 1, together with instructions for its use as a herbcide.

86. A pack as claimed in claim 85, wherein the compound of the general formula I is the compound claimed in any one of claims 2 to 46.

87. A pack as claimed in claim 85, wherein the compound of the general formula I is the compound claimed in any one of claims 47 to 52.