DD141990A5 - HERBICIDE MEDIUM - Google Patents

Description

210 941

Herbicidal agent Field of application of the invention

The present invention relates to herbicidal compositions containing novel phenoxyacetic acid derivatives, to a plurality of processes for their preparation and to their use as herbicides.

Characteristic of the known technical solutions

Numerous phenoxyacetic acid derivatives are known (cf. German Offenlegungsschrift 2,732,442 and German Offenlegungsschrift 2,639,796).

In particular, it has become known that 3- (4-chlorophenoxy) -O-C-phenoxy-propionic acid ethyl ester is suitable for controlling weeds (see DE-OS 2 716 189) "However, the effectiveness of this substance is, especially at low dosages , not always quite satisfactory ·

Object of the invention

The aim of the invention is the provision of agents with improved herbicidal activity and broad selectivity.

Explanation of the essence of the invention

The invention has for its object to provide new phenoxy

210 941 - 2 - 22. -5. 1979

54 927 12

to find acetic acid derivatives which have the desired improved properties ·

According to the invention as active ingredients in herbicidal agents, novel phenoxyacetic acid derivatives of the formula

applied,

.Cl P-CH ₂ -CO-R

(D Cl

210 941 -s

in which

R is hydroxy, optionally substituted by alkoxy, alkylthio, carbalkoxy, phenylmethylaminocarbonyl and / or halogen substituted alkoxy, amino, hydrazino, optionally substituted by alkoxy or dialkylamino alkylamino, dialkylamino, alkenylamines, arylamino or N-aryl-N-alkyl-amino, wherein the aryl radical each may be substituted by alkyl, alkoxy, carbalkoxy, halogen and / or nitro, further for an optionally substituted by alkyl, via nitrogen-bonded saturated heterocyclic ring with 5 or 6 ring members, or for the rest of the formula

stands.

The invention also provides methods for producing

ment of phenoxyacetic acid derivatives of the formula (I). That's how you get

a) the compounds of the formula (I) by reacting the Phenoxyessigsäurechlorid the formula

210 941

0-CH-COCl

(ID

with compounds of the formula

HR (III) • r in which. '

R has the meaning given above,

if appropriate in the presence of an acid acceptor and if appropriate in the presence of a diluent,

or

b) the compound of the formula (I) in which R is methoxy by reacting the diphenyl ether of the formula

(IV)

210 941 -s

with bromoacetic acid methyl ester of the formula

Br-CH ₂ -COOCH ₃ (V)

in the presence of an acid acceptor and in the presence of a diluent,

5 or

c) the compound of the formula (I) in which R is hydroxyl, by reacting the compound of the formula

treated with bases in the presence of a diluent and then acidified,

d) those compounds of the formula (I) in which R is alkoxy having more than one carbon atom, by reacting the compound of the formula

210 941

-CH-COOCH ₃ ^(Ι '*

with alcohols of the formula

HOR ¹ (VI)

in which

R ^{1 is} alkyl having more than one carbon atom,

optionally in the presence of an alcoholate and optionally in the presence of a diluent.

The invention further relates to the use of phenoxyacetic acid derivatives of the formula (I) as herbicides.

Surprisingly, the phenyloxyacetic acid derivatives according to the invention have very good herbicidal properties. So they are suitable for example. for the selective control of weeds in different crops. Above all, they show an excellent action against hard to control weeds, e.g. Galium.

210 941

The substances according to the invention thus represent an enrichment of the art.

The phenoxyacetic acid derivatives of the invention are generally defined by the formula (I). In the formula

(I) R preferably represents hydroxyl or straight-chain or branched alkoxy having 1 to 4 carbon atoms, where each of these alkoxy radicals may be substituted one or more times, identically or differently. Suitable substituents here are preferably alkoxy having 1 to 4, in particular 1 to 2 carbon atoms, alkylthio having 1 to 4, in particular 1 to 2 Kohlenstoffa.tomen, carbalkoxy having 1 to 4, in particular 1 to 2 carbon atoms in the alkoxy group, phenylmethylaminocarbonyl and Chlorine and bromine. Furthermore, R preferably represents amino, hydrazino, optionally substituted by alkoxy having 1 to 4 carbon atoms or by dialkylamino having 1 to 4 carbon atoms per alkyl substituted alkylamino having 1 to 4 carbon atoms, dialkylamino having 1 to 4 carbon atoms per alkyl group, alkenylamines having up to 4 carbon atoms or for phenylamino or N-phenyl-N-alkyl-amino having 1 to 4 carbon atoms in the alkyl group, wherein the phenyl radical may be substituted by alkyl having 1 to 4 carbon atoms, alkoxy having 1 to 4 carbon atoms, carbalkoxy having 1 to 4 respectively Carbon atoms in the alkoxy group, fluorine, chlorine, Bom and / or nitro. In addition, R preferably represents an optionally methyl-substituted, nitrogen-bonded saturated heterocyclic ring having 5 or 6 ring members, wherein in addition to the nitrogen atom bonded to the carbonyl group, another nitrogen or oxygen atom may be present in the ring. As examples of such hetero-

210 941 -β-

Cyclen be called piperidine, 2-methyl-piperidine, pyrrolidine, piperazine, pyrazolidine and morpholine. Finally, R is preferably the radical of the formula

5 Examples of phenoxyacetic acid derivatives of the formula (I) according to the invention which may be mentioned in detail are:

3- (2,6-dichloro-4-trifluoromethyl-phenoxy) -phenoxyacetic acid

Methyl 3- (2,6-dichloro-4-trifluoromethyl-phenoxy) -ph-c-acoxyacetate 3- (2,6-dichloro-4-trifluoromethyl-phenoxy) -phenoxyacetic acid ethyl ester

3- (2,6-Dichloro-4-trifluoromethyl-phenoxy) -phenoxyacetic acid isopropyl ester 3- (2,6-dichloro-4-trifluoromethyl-phenoxy) -phenoxyacetic acid n-butyl ester

3- (2,6-Dichloro-4-trifluoromethyl-phenoxy) -phenoxyacetic acid (2-methoxy) ethyl ester 3- (2,6-dichloro-4-trifluoromethyl-phenoxy) -phenoxy-acetic acid (2-methylthio) -ethyl ester 3- (2,6-dichloro-4-trifluoromethyl-phenoxy) -phenoxyessigsäure- (2-ethoxycarbonyl) ethyl ester

210 94t

3- (2,6-Dichloro-4-trifluoromethyl-phenoxy) -phenoxyacetic acid (2-phenylmethyl-aminocarbonyl) ethyl ester 3- (2,6-dichloro-4-trifluoromethyl-phenoxy) -phenoxyacetic acid (2-chloro) ethyl ester

3- (2,6-dichloro-4-trifluoromethyl-phenoxy) -phenoxy acetic acid-methylamide

3- (2,6-dichloro-4-trifluoromethyl-phenoxy) -phenoxyacetic acid (2-methoxy) ethylamide 3- (2,6-dichloro-4-trifluoromethyl-phenoxy) -phenoxy-

10 acetic acid (2-dimethylamino) ethylamide

3- (2,6-dichloro-4-trifluoromethyl-phenoxy) -phenpxy-

acetic acid dimethylamide

3- (2,6-dichloro-4-trifluoromethyl-phenoxy) phenoxy-

acetic acid-buten-2-yl-amide

3- (2,6-dichloro-4-trifluoromethyl-phenoxy) -phenoxyacetic acid (4-nitro-phenyl) -methylamide 3- (2,6-dichloro-4-trifluoromethyl-phenyD-phenoxy-

acetic acid piperidide

3- (2,6-dichloro-4-trifluoromethyl-phenoxy) phenoxy-

20 acetic acid pyrrolidide

3- (2,6-dichloro-4-trifluoromethyl-phenoxy) -phenosylacetic acid piperazide

3- 12, 6-dichloro-4-trifluoromethyl-phenoxy) -phenoxyessigsäurepyrazolidid

3- (2,6-dichloro-4-trifluoromethyl-phenoxy) -phenoxyacetic acid morpholide

_{3-2.6-dichloro-4-r} trifluormehtyl phenoxy) -phenoxy-acetic acid · (2-benzothiazolyl) -methyl-amide.

210 941 -ί-

If 3- (2,6-dichloro-4-trifluoromethyl-phenoxy) -phenoxy-acetic acid chloride and diethylamine are used as starting materials, the course of the reaction by process (a) according to the invention can be represented by the following formula:

0-CH ₂ -CO-Cl

0-CH ₂ -CO-N

If 2,6-dichloro-4-trifluoromethyl-3- ^l- hydroxydiphenyl ether and methyl bromoacetate are used as starting materials, the course of the reaction by process (b) according to the invention can be represented by the following formula scheme:

210 941

-ΛΑ -

Br-CH ₂ -COOCH ₃

-HBr

0-CH ₂ -COOCH ₃

If 3- (2,6-dichloro-4-trifluoromethyl-phenoxy) -phenoxy-acetic acid methyl ester and sodium hydroxide are used as starting materials, the course of the reaction can be reproduced by the process (c) according to the invention by the following equation:

F ₃ C

Cl

Cl

0-CH ₂ -COOCH ₃

1) NaOH 2} HCl

- NaCl -CH ₃ OH

0-CH ₂ -COOH

Using 3- (2,6-dichloro-4-trifluoromethyl-phenoxy) -phenoxy-acetic acid methyl ester and n-butanol as

210 941

Starting materials, the reaction sequence by the process (d) according to the invention can be represented by the following equation:

P-CH ₂ -COOCH ₃

n-C.H.-OH

-CH ₃ OH

O-CH ₂ -COO-nC ₄ H

The phenoxyacetic acid chloride required as starting material for carrying out the process (a) according to the invention is defined by the formula (II).

The compound in question is not yet known, but it can be prepared in a simple manner by methods known in principle. To obtain the Phenoxyessigsäurechlorid of formula (II), by reacting the corresponding acid of the formula

CH ₂ -COOH

210 94t "-" -

with chlorinating agents, such as thionyl chloride, optionally in the presence of diluents, such as ethylene chloride, at temperatures between ^{0 0} C and 50 ⁰ C, preferably between 10 C and 30 C reacted.

The substituted phenoxyacetic acid of the formula (I ") is also not yet known

However, also produce in a simple manner by methods known in principle. Thus, the sub-acidified phenoxyacetic acid of the formula (I ") is obtained by reacting the corresponding methyl ester of the formula

-CH _n -COOCH ₀ (I ')

with strong bases, such as sodium hydroxide or potassium hydroxide, in the presence of a diluent, such as methanol or water, at temperatures between 20 ° C and 100 ⁰ C, preferably treated between 40 ° C and 80 ° C.

The substituted phenoxyacetic acid methyl ester of the formula (I ¹ ) is also not yet known. However, it can also be produced in a simple manner by methods known in principle. Thus, the substituted Pehnoxyessigsäuremethylester of formula (I ¹ ), by the diphenyl ether of the formula

(IV)

210 94t

with bromoacetic acid methyl ester of the formula

Br-CH ₂ -COOCl ₃ (V)

in the presence of an acid binder, such as sodium methylate, sodium ethylate or potassium carbonate, in the presence of a polar diluent, such as methanol or acetonitrile, at temperatures between 2O ° C and 1CO ° C, preferably 3O ° C and 8O ⁰ C.

The diphenyl ether of the formula (IV) is not yet known. However, it can be prepared in a simple manner by methods known in principle. Thus, 10% of the diphenyl ether of the formula (IV) _{r is obtained} by reacting halogenated trifluoromethylbenzenes of the formula

in which

Hal is chlorine or bromine, 15 with resorcinol of the formula

210 941

(VIII)

in the presence of an acid binder and in the presence of a diluent at temperatures between 20 C and 2OO ° C, preferably between 5O ° C and 15O ° C.

Suitable acid binders here are all customary bases. These include, preferably, alkali hydroxides such as sodium hydroxide and potassium hydroxide and alkaline earth hydroxides such as calcium hydroxide.

Suitable diluents are all customary inert aprotic polar solvents. These include, preferably, amides, such as hexamethylphosphoric triamide, dimethylformamide or dimethylacetamide, furthermore sulfoxides, such as dimethyl sulfoxide, furthermore ketones, such as methyl ethyl ketone, and also nitriles, such as acetonitrile and sulfolane.

Die'halogenieren trifluoromethyl-benzenes of the formula (VII) are known.

The compounds which can be further used as starting materials in carrying out the process (a) according to the invention are generally defined by the formula (III). In the formula (III), R preferably represents those radicals which have already been mentioned as preferred in connection with the description of the substances of the formula (I) according to the invention.

210 941 -ie

The compounds of the formula (III) are known. As examples may be mentioned in detail:

Water methanol ethanol propanol isopropanol n-butanol

tert-butanol 2-methoxy-ethanol. 2-ethoxy-methanol 2-methylthio-ethanol ethanol-carbonyl-methanol 2-ethoxycarbonyl-ethanol 2-phenylmethylaminocarbonyl-ethanol 2-chloro-ethanol ammonia hydrazine methylamine ethylamine n-propylamine isopropylamine 2-methoxy-ethylamine 2-dimethylamino-ethylamine dimethylamine diethylamine di- n-propylamine buten-2-yl-amine

210 941

aniline

Phenyl-methyl-amine 4-methyl-aniline

4-methoxy-aniline 5 4-a'thoxycarbonyl-aniline 4-chloroaniline 4-nitro-aniline piperidine

2-methylpiperidine 10 pyrrolidine piperazine pyrazolidine morpholine 2-benzothiazolyl-methyl-amine

Suitable diluents for carrying out the process (a) according to the invention are all inert organic solvents. These include preferably ketones, such as diethyl ketone and methyl isobutyl ketone, furthermore nitriles, such as acetonitrile and propionitrile, furthermore ethers, such as tetrahydrofuran and dioxane, in addition aliphatic and aromatic hydrocarbons, such as petroleum ether, benzene, toluene and xylene, also halogenated hydrocarbons, such as methylene chloride, carbon tetrachloride, chloroform and chlorobenzene, in addition esters such as ethyl acetate, and formamides such as dimethylformamide.

In some cases, where the compound of formula (III) is a liquid component.

210 941 - «-

it is unnecessary to add a diluent. However, a diluent may also be added in these cases.

Al3 acid binders can be any of the commonly used inorganic and organic acid acceptors when practicing process (a) of the invention. These include, preferably, alkali metal carbonates, for example sodium carbonate, potassium carbonate and sodium bicarbonate, lower tertiary alkylamines, aralkylamines, aromatic amines or cycloalkylamines, e.g. Triethylamine, dimethylbenzylamine, pyridine and diazabicyclooctane.

If the compound of the formula (III) is an amine, then this amine used in excess can also act as acid binder.

The reaction temperatures can be varied within a relatively wide range in the process (a) according to the invention. In general, one works at temperatures between 20 ⁰ C and 1OO ° C, preferably between 30 ° C and 80 ° C.

In carrying out the process (a) according to the invention is used for 1 mol of phenoxyacetic acid chloride of the formula (II) preferably 1 to 2 moles or a larger excess of a compound of formula (III) and optionally 1 to 2 moles of acid binder. - The isolation of the substances of the invention

210 94f - «-

mel (I) is carried out by customary methods. In general, the procedure is followed by adding the reaction mixture after completion of the reaction either directly or after prior concentration under reduced pressure with an organic solvent such as toluene or Methylenchlo, the organic phase is then separated, washed and concentrated after drying.

The diphenyl ether which can be used as the starting material in carrying out the process (b) according to the invention is precisely defined by the formula (IV).

This substance is obtained, e.g. according to the method which has already been described in detail in connection with the preparation of the starting materials for process (a).

The in the process (b) further required as starting material bromoacetic acid methyl ester of the formula (V) is known.

The reaction conditions to be observed in carrying out the process (b) according to the invention, as well as the acidic acid and diluent to be used in the reaction, have already been described in detail in connection with the preparation of the starting materials for process (a) according to the invention.

210 941 -z-

In carrying out the method according to the invention

(B) is used for 1 mol of diphenyl ether of the formula (IV) is preferably 1 to 2 mol of methyl omertric acid ester of the formula (V) and 1 to 2 moles of acid binder. The isolation of the reaction product is carried out: in the case of the process (b) according to conventional methods. In general, the procedure is followed by concentrating the reaction mixture after completion of the reaction, the remaining residue in an organic solvent such as methylene chloride, receives, the solution is filtered, washed and concentrated after drying under reduced pressure.

The in carrying out the method according to the invention

(c) Methylene phenoxyacetate required as the starting material is precisely defined by the formula (I ¹ ).

The phenoxyacetic acid methyl ester of the formula (I ¹ ) is not yet known. This substance is obtained, for example, by the method which has already been described in detail in connection with the preparation of the starting materials for process (a).

The reaction conditions to be observed in carrying out the process (c) according to the invention, as well as the bases and diluents to be used in the reaction, have already been described in detail in connection with the preparation of the starting materials for process (a) according to the invention.

210 941 -u

In carrying out the process (c) according to the invention is used for 1 mol of methyl phenoxyacetate of the formula (I ¹ ) is preferably 1 to 2 moles of base. The isolation of the reaction product is carried out in the case of the process according to the invention (c) by customary methods. In general, the procedure is followed by pouring the reaction mixture into water after completion of the reaction, filtering the solution, then acidifying and extracting the acid which forms in solid form.

In carrying out the method according to the invention

(d) is the methyl phenoxyacetate as starting material, which has already been mentioned in connection with the description of the method (c) according to the invention.

The alcohols to be used as starting materials in the process (d) according to the invention are generally defined by the formula (VI). In the formula (VI), R preferably represents straight-chain or branched alkyl having 2 to 4 carbon atoms.

Specific examples of compounds of the formula (VI) are:

Ethanol n-propanol isopropanol 2 5 i-butanol n-butanol sec-butanol tert-butanol

210 941

The alcohols of the formula (VI) are known.

In the process (d) according to the invention, the reaction components of the formula (VI) used in excess can simultaneously function as diluents. However, it is also possible to use inert organic solvents as diluents.

The reaction according to the process (d) according to the invention is preferably carried out in the presence of an alkoxide, e.g. Sodium methylate, performed.

The reaction temperatures in the process according to the invention (d) can be varied within a relatively wide range. In general, one works at temperatures between 60 ° C and 120 ° C.

between 2O ° C and 200 ° C, preferably between

When carrying out the process (d) according to the invention, an excess of alcohol of the formula (VI) and, suitably, a catalytic amount of alkoxide are used per mole of methyl phenoxyacetate of the formula (I ¹ ). - The isolation of the reaction products by conventional methods. In general, the procedure is followed by concentrating the reaction mixture after completion of the reaction, stirring the remaining residue with an organic solvent, filtering the resulting solution, washing and drying after drying.

25 equals.

210 941

The active compounds according to the invention influence plant growth and can therefore be used as defoliants, desiccants, haulm killers, anti-sprouting agents and in particular as weedkillers. Weeds in the broadest sense are all plants that grow in places where they are undesirable. Whether the substances according to the invention act as total or selective herbicides essentially depends on the amount of aL used.

The active compounds according to the invention may e.g. used in the following plants:

Pikotyle weeds of the genera : Sinapis, Lepidium, Galium, Stellaria, Matricaria, Anthemis, Galinsoga, Chenopodium, Urtica, Senecio, Amaranthus, Portulaca, Xanthium, Convolvulus, Ipomoea, Polygonum, Sesbania, Ambrosia, Cirsium, Carduus, Sonchus, Solanum, Rorippa , Rotala, Lindernia, Lamium, Veronica, Abutilon, Emex, Datura, Viola, Galeopsis, Papaver, Centaurea.

Dicotyledonous cultures of the genera : Gossypium, Glycine, Beta, Daucus, Phaseolus, Pisum, Solanum, Linwn, Ipomoea, Vicia, Nicotiana, Lycopersicon, Arachis, Brassica, Lactuca, Cucumis, Cuburbita.

Monocotyledonous weeds of the genera : Echinochloa, Setaria, Panicum, Digitaria, Phleum, Poa, Festuca, Eleusine, Brachiaria, Loium, Bromus, Avena, Cyperus, Sorghum, Agropyron, Cynodon, Monocharia, Fimbristylis, Sagittaria, Eleocharis, Scirpus, Paspalum, Ishaemum , Spenoclea, Dadyloctenium, Agrostis, Alopecurus, Apera.

210 941 -. »-

Monocot cultures of the genera ; Oryza, Zea, Triticum, Hordeum, Avena, Seeale, Sorghum, Panicum, Saccharum, Pineapple, Asparagus, Allium.

However, the use of the active compounds according to the invention is by no means restricted to these genera, but extends in the same way to other plants.

The compounds are useful depending on the concentration for total weed control e.g. on industrial and railway tracks and on paths and squares with and without tree cover. Similarly, the compounds for weed control in permanent crops, e.g. Forest, ornamental, fruit, wine, citrus, nut, banana, coffee, tea, gum, oil palm, cocoa, berry fruit and hop plants and used for selective weed control in annual crops.

The active compounds according to the invention are particularly suitable for controlling weeds in oats, wheat and maize. They show a very good action against hard-to-control weeds, e.g. Galium.

The active compounds according to the invention, as such or in their formulations, can also be used for combating weeds in admixture with known herbicides, ready-to-use formulation or tank mixing being possible.

210 941 -2s-

The active compounds can be converted into the customary formulations, such as solutions, emulsions, wettable powders, suspensions, powders, dusts, pastes, soluble powders, granules, suspension emulsion concentrates, active substance-impregnated natural and synthetic substances and microencapsulations in polymeric substances. ·

These formulations are prepared in a known manner, e.g. by mixing the active compounds with extenders, ie liquid solvents and / or solid carriers, if appropriate using surface-active agents, ie emulsifiers and / or dispersants and / or foam-forming agents. In the case of using water as an extender, e.g. also organic solvents can be used as auxiliary solvents. As liquid solvents are essentially in question:

Aromatics, such as xylene, toluene, or Alky! Naphthalenes, chlorinated aromatic or chlorinated aliphatic hydrocarbons, such as chlorobenzenes, chloroethylenes or methylene chloride, aliphatic hydrocarbons, such as cyclohexane or paraffins, e.g. Petroleum fractions, alcohols, such as butanol or glycol, and their ethers and esters, ketones, such as acetone, methyl ethyl ketone, methyl isobutyl ketone or cyclohexanone, strongly polar solvents, such as dimethylformamide and dimethylsulfoxide, and water; solid carriers: ground natural minerals, such as kaolins, clays, talc, chalk, quartz, attapulgite,

210 941

-Ab -

Montmorillonite or diatomaceous earth and ground synthetic minerals such as fumed silica, alumina and silicates; as solid carriers for granules: crushed and fractionated natural rocks such as calcite, marble, pumice, sepiolite, dolomite and synthetic granules of inorganic and organic flours and granules of organic material such as sawdust, coconut shells, corn cobs and tobacco stalks; as emulsifying and / or foam-forming agents: nonionic and anionic emulsifiers, such as polyoxyethylene fatty acid esters, polyoxyethylene fatty alcohol ethers, e.g. Alkylaryl polyglycol ethers, alkyl sulfonates, alkyl sulfates, aryl sulfonates and protein hydrolysates; as a dispersing agent: e.g. Lignin - liquor liquor and methylcellulose.

Adhesives such as carboxymethylcellulose, natural and synthetic powdery, granular or latex-type polymers, such as gum arabic, polyvinyl alcohol, polyvinyl acetate, can be used in the formulations.

Dyes such as inorganic pigments, e.g. Iron oxide, titanium oxide, ferrocyan blue and organic dyes such as alizarin, azo metal phthalocyanine dyes and trace nutrients such as salts of iron, manganese, boron, copper, cobalt, molybdenum and zinc.

The formulations generally contain between 0.1 and 95% by weight of active ingredient, preferably between 0.5 and 90 %.

210 941 '"22- 5-1979

£. IW 7 ^ I 54 927 12

The active compounds according to the invention can be present in the formulations in a mixture with other known active compounds, such as fungicides, insecticides and acaricides.

The active compounds can be used as such, in the form of their formulations or in the use forms prepared therefrom, such as ready-to-use solutions, emulsions, suspensions, powders, pastes and granules. The application is carried out in the usual way. z · B · by spraying, spraying, dusting, spreading and pouring,

The application is possible both by the post-emergence method and by the pre-emergence method, it preferably takes place according to the post-emergence method.

The amount of active substance used can vary within a wide range. It depends essentially on the type of effect desired. In general, the application rates are between 0.1 and 25 kg / ha, preferably between 0.25 and 10 kg / ha.

embodiment

The good herbicidal activity _{e of} the active compound (1) according to the invention is evident from the following example:

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Example A Post emergence test Solvent: 5 parts by weight acetone

Emulsifier: 1 part by weight of alkylaryl polyglycol ether

To prepare a suitable preparation of active compound, 1 part by weight of active compound is mixed with the stated amount of solvent, the indicated amount of emulsifier is added and the concentrate is diluted with water to the desired concentration.

With the preparation of active compound is injected test plants, which have a height of 5 - 15 cm so that the amounts of active ingredient per unit area shown in the table are applied. The concentration of Spritzbrilhe is chosen so that in 2000 1 water / ha, the amounts of active ingredient indicated in the table are applied. After three weeks, the degree of damage of the plants is rated in % damage in comparison to the development of the untreated control. It means:

0 % = no effect (as untreated control) 100 % = total destruction

The active ingredient (1) according to the invention has very good herbicidal properties.

Table A post-emergence test

Active ingredient active ingredient Cheno-Sina-Galin- Matri- Amaran- Galium Portu- Oat Wheat Maize

effort podium pis soga caria thus lacca kg / ha

100 100 100 80 100 100 100 10 20 40

210 941

Preparation Examples example 1

0-CH ₂ -COOC ₂ H ₅

In a mixture of 24.2 g (0.075 mol) of 2,6-dichloro-4-trifluoromethyl-3'-hydroxy-diphenyl ether, 12 g of potassium carbonate and 80 ml of acetonitrile at a temperature of 45 to 50 C within 2 hours 13 , 8 g of ethyl bromoacetate are added dropwise. The mixture is stirred for 3.5 hours at 50 to 60 C and then worked up by pouring the reaction mixture into water, the resulting mixture extracted several times with toluene, the combined organic phases are dried and then concentrated under reduced pressure. Obtained in this way 23 * 7 g (77.3% of theory) of 3- (2,6-dichloro-4-trifluoromethyl-phenoxy) -phenoxy-acetic acid ethyl ester in the form of an orange-colored solid of melting point 61-62 ° C.

Analysis:

Molar formula: C ₁₇ H ₁₃ Cl ₂ F ₃ O.

calculated: 20 found:

49.9% C; 49.9% C;

3.2% H;

3.3% H;

17.4% Cl 17.1% Cl

210 941

Preparation of required as starting material 2,6-dichloro-4-trifluoromethyl-3'-hydroxy-diphenyl ether of the Forme.l

Cl OH

In a mixture of 330 g (3 mol) of resorcinol and 111 g (1.5 Hol) of calcium hydroxide in 2 l of dimethyl sulfoxide at 120-13O ⁰ C within 7 hours 358 g (1.5 mol) of 3,4,5- Trichloro-benzotrichloride dripped. Subsequently, the reaction mixture is stirred for 8 hours at 130 ⁰ C. After cooling to room temperature, the reaction mixture is poured into 7 1 of water, whereby the reaction product separates oily. It is extracted with 3 l of toluene, the organic phase is separated off and concentrated after drying. The remaining residue is distilled. Obtained in this way 350 g (73% of theory) of 2,6-dichloro-4-trifluoromethyl-3'-hydroxy-diphenyl ether in the form of a solid of melting point 64-65 ° C.

 Bp 123-13 ° C / 0.15 torr

Example 2

0-CH ₂ -COOH

210 941

To 41 g (0.1 mol) of ethyl 3- (2,6-dichloro-4-trifluoromethyl-phenoxy) phenoxyacetate and 70 ml of methanol are added 30 ml of water and 15 ml of concentrated sodium hydroxide solution and left at 50 for 5 hours - Stir 60 ° C. Then worked up by pouring the reaction mixture into 0.5 1 of water, the solution was filtered hot, acidified and sucks the resulting crystalline product. This gives 35 g (87.5% of theory) of 3- (2,6-dichloro-4-trifluoromethyl-phenoxy) -od-phenoxyacetic acid in the form of an ivory-colored solid substance of the melting point

104 C. 47 3 ^C 1 5H ₉ Cl ₂ F ₃ ° 4 H; 1 8th, 6 Cl Analysis: 47 1 C 2 , 36 H; 1 7, 9 Cl Molecular formula C ; 2 2 calculated: found:

According to one or more of the processes described above, the substances listed by formula in the table below are prepared.

Table 1

cf, - <O> -o- (O

Example no.

melting point

-O-CH ₃ 46-47 C

210 941

Example No. Melting point

4 5 67 8

10 ° ^C 4 ^H 9-n

- ° - ^C 4 ^H 9 -iso ⁶ -O-CH ₂ -CO ₂ CH ₃ - ° - ^CH 2 ^-CO 2 ^C 4 ^H 9-n

CH ₃

o-cH ₂ -co ^ / l ^^

CH ₃

^ ⁵

^{X is} CH ₂ -OC ₂ H ₅

NH-CH ₂ -CH = CH ₂

210 941 - »·» -

Example no.

melting point

-N-

CH.

-γ)

CH,

-NHO \ /

-N (CH ₃ )

NH-157 ° C

Claims (4)

invention claim R is hydroxy, alkoxy, alkylthio, carbalkoxy, phenylmethylaminocarbonyl and / or halogen-substituted alkoxy, amino, hydrazino, optionally substituted by alkoxy or dialkylamino alkylamino, dialkylamino, alkenylamines, arylamino or N-aryl-H-alkyl-amino, wherein the Aryl radical may be substituted in each case by alkyl, alkoxy, carbalkoxy, halogen and / or nitro, further for an optionally substituted. Alkyl-substituted, nitrogen-bonded saturated heterocyclic ring having 5 or 6 ring members, or for the rest of the formula stands, in admixture with extenders and / or surface-active agents. 210941 - 36 - 22. 5. 1979 54 927 12 2. A method for controlling weeds, characterized in that one lets act phenoxyacetic acid derivatives according to item 1 on the weeds and / or their habitat · 3 · Use of phenoxyacetic acid derivatives Item 1, characterized in that they are used for combating - weeds. 4 · Process for the preparation of herbicidal compositions, characterized in that phenoxyacetic acid derivatives according to item 1 are mixed with extenders and / or surface-active agents.