WO1998040362A1

WO1998040362A1 - Substituted arylalkyluracils

Info

Publication number: WO1998040362A1
Application number: PCT/EP1998/001056
Authority: WO
Inventors: Roland Andree; Mark Wilhelm Drewes; Markus Dollinger
Original assignee: Bayer Aktiengesellschaft
Priority date: 1997-03-10
Filing date: 1998-02-25
Publication date: 1998-09-17
Also published as: DE19709703A1; AU6724898A

Abstract

The invention relates to novel substituted arylalkylruracils of general formula (I), wherein A stands for straight-chained or branched alkanediyl with two or more carbon atoms, Ar means in each case optionally substituted phenyl or naphthyl, R<1> is hydrogen, amino or optionally substituted alkyl, R<2> stands for halogen-substituted alkyl, and R<3> means hydrogen, halogen or alkyl. The invention also relates to a method for the production and use thereof as herbicides.

Description

Substituted arylalkyl uracils

The invention relates to new substituted arylalkyluracils, processes for their preparation and their use as herbicides.

A large number of substituted benzyluracils are already known from the (patent literature (cf. US 5391541, WO 9504461, WO 9701543). However, these compounds have not gained any particular significance.

We have now found new substituted arylalkyluracils of the general formula (I)

in which

A stands for straight-chain or branched alkanediyl with two or more carbon atoms,

Ar represents in each case optionally substituted phenyl or naphthyl,

R ^{1 represents} hydrogen, amino or optionally substituted alkyl,

R ^{2 represents} halogen substituted alkyl and

R ^{3 represents} hydrogen, halogen or alkyl.

The new substituted arylalkyluracils of the general formula (I) are obtained if (a) aminoalkenates of the general formula (II)

in which

R ² and R ^{3 have} the meanings given above and

A ^{1 represents} alkyl, aryl or arylalkyl,

with arylalkyl urethanes (arylalkyl carbamates) of the general formula (III)

in which

A and Ar have the meanings given above and

A ^{2 represents} alkyl, aryl or arylalkyl,

if appropriate in the presence of a reaction auxiliary and if appropriate in the presence of a diluent,

or if you

(b) substituted arylalkyluracils of the general formula (Ia),

in which

A, Ar, R ² and R ^{3 have} the meanings given above,

with l-aminooxy-2,4-dinitro-benzene or with alkylating agents of the general formula (IV)

XA ³ (IV)

in which

A ^{3 represents} optionally substituted alkyl and

X represents halogen or the grouping -O-SO ₂ -OA ³ ,

if appropriate in the presence of a reaction auxiliary and if appropriate in the presence of a diluent.

The new substituted arylalkyluracils of the general formula (I) are notable for strong herbicidal activity. They also show good tolerance to important crops, such as Corn.

The invention preferably relates to compounds of the formula (I) in which A represents straight-chain or branched alkanediyl having two to four carbon atoms,

Ar for each optionally by amino, nitro, cyano, carboxy, carbamoyl, thiocarbamoyl, fluorine, chlorine, bromine, C1-C4-alkyl (which is optionally substituted by fluorine and / or chlorine) and / or C 1 -C 4 -alkoxy (which optionally substituted by fluorine and / or chlorine)

Phenyl or naphthyl,

R ^{1 represents} hydrogen, amino or optionally by cyano, fluorine or

Chlorine-substituted alkyl having 1 to 4 carbon atoms,

R ^{2 represents} fluorine and / or chlorine-substituted alkyl having 1 to 4 carbon atoms and

R ^{3 represents} hydrogen, fluorine, chlorine, bromine or alkyl having 1 to 4 carbon atoms.

The invention relates in particular to compounds of the formula (I) in which

A for ethane-l, l-diyl ("ethylidene"), ethane-l, 2-diyl ("dimethylene"), propane-1, 1-diyl ("propylidene"), propane-l, 2-diyl or propane -l, 3-diyl ("trimethylene").

Ar represents phenyl optionally substituted by amino, nitro, cyano, carboxy, carbamoyl, thiocarbamoyl, fluorine, chlorine, bromine, methyl, ethyl, trifluoromethyl, methoxy, ethoxy, difluoromethoxy and / or trifluoromethoxy,

R ^{1 represents} hydrogen, amino, methyl or ethyl,

R ² represents methyl or ethyl substituted by fluorine and / or chlorine and R ^{3 represents} hydrogen, chlorine, bromine or methyl.

The general definitions of radicals listed above or those specified in preferred ranges apply both to the end products of the formula (I) and correspondingly to the starting or intermediate products required in each case for the preparation. These radical definitions can be combined with one another, that is to say also between the specified preferred ranges.

If, for example, 3-amino-2,4,4,4-tetrafluoro-crotonic acid methyl ester and N- [l- (4-chlorophenyl) ethyl] -O-methyl-carbamate are used as starting materials, the course of the reaction can be as follows Process (a) according to the invention are outlined by the following formula:

If, for example, l- [2- (2-fluoro-4-trifluoromethyl-phenyl) -ethyl] -5-chloro-4-chlorodifluoromethyl-3,6-dihydro-2,6-dioxo-l (2H) -pyrimidine and Ethyl bromide as starting materials, the course of the reaction in process (b) according to the invention can be outlined using the following formula:

The aminoalkenic acid esters to be used as starting materials in process (a) according to the invention for the preparation of compounds of the formula (I) are: Formula (II) generally defined. In the formula (II), R ² and R ³ preferably or in particular have those meanings which have been given above or in connection with the description of the compounds of the formula (I) according to the invention preferably or as particularly preferred for R ² and R ³ ; A ¹ is preferably C 4 -C 4 -alkyl, phenyl or benzyl, in particular methyl or ethyl.

The starting materials of the general formula (II) are known and / or can be prepared by known processes (cf. J. Heterocycl. Chem. 9 (1972), 513- 522).

Formula (III) provides a general definition of the arylalkyl urethanes (arylalkyl carbamates) to be used further as starting materials in process (a) according to the invention. In formula (III), A and Ar preferably or in particular have those meanings which have already been mentioned above in connection with the description of the compounds of the formula (I) according to the invention preferably or as particularly preferred for A and Ar; A ² is preferably C _j -C4 alkyl, phenyl or benzyl, especially methyl or ethyl.

The starting materials of the general formula (III) are known and / or can be prepared by known processes (cf. J. Org. Chem. 45 (1980), 4519-4522; loc. Cit. 48 (1983), 2520-2527; Synthesis 1980, 385-387; Tetrahedron: Asymmetry 1992, 281-286; loc. Cit. 1994, 363-370).

The arylalkyl urethanes (arylalkyl carbamates) of the general formula (III) are obtained, for example, if arylalkyl amines of the general formula (V)

H ₂ NA-Ar (V)

in which

A and Ar have the meanings given above, with chloroformic acid esters of the general formula (VI)

A ² -O-CO-Cl (VI)

in which

A ^{2 has} the meaning given above,

if appropriate in the presence of an acid acceptor, such as pyridine, and if appropriate in the presence of a diluent, such as methylene chloride, at temperatures between 0 ° C. and 100 ° C. (see the preparation examples)

The substituted arylalkyluracils to be used as starting materials in the process (b) according to the invention for the preparation of compounds of the formula (I) are generally defined by the formula (Ia) In the formula (Ia), A, Ar, R ² and R ³ preferably or in particular those meanings which have already been given above in connection with the description of the compounds of the formula (I) according to the invention preferably or as particularly preferred for A, Ar, R ² and R ³

The starting materials of the general formula (Ia) for process (b) are also the subject of the present application as new substances; they can be prepared by process (a) according to the invention

The alkylating agents to be used further as starting materials in process (b) according to the invention are generally defined by the formula (IV). In formula (IV), R ¹ and R ² preferably or in particular have those meanings which have already been mentioned above in connection with the description of the inventive Compounds of formula (I) preferably or as particularly preferred for R ¹ and R ^{2 have been} specified

Stand in the formula (IV) A ³ preferably for alkyl with 1 to 4 carbon atoms optionally substituted by cyano, fluorine or chlorine, in particular for methyl or ethyl, and

X preferably for fluorine, chlorine, bromine or iodine, or for the grouping

-O-SO ₂ -OA ³ , especially for chlorine or bromine.

The starting materials of formula (IV) are known organic synthetic chemicals.

The usual inorganic or organic bases or acid acceptors are generally suitable as reaction auxiliaries for processes (a) and (b). These preferably include alkali metal or alkaline earth metal acetates, amides, carbonates, bicarbonates, hydrides, hydroxides or alkanolates, such as sodium, potassium or calcium acetate, lithium, sodium or potassium - or calcium amide, sodium, potassium or calcium carbonate, sodium, potassium or calcium hydrogen carbonate, lithium, sodium, potassium or calcium hydride, lithium, sodium, potassium or calcium hydroxide, sodium or potassium methoxide, ethanolate, n- or -i-propanolate, -n-, -i-, -s- or -t-butanolate; basic organic nitrogen compounds, such as trimethylamine, triethylamine, tripropylamine, tributylamine, ethyl-diisopropylamine, N, N-dimethyl-cyclohexylamine, dicyclohexylamine, ethyl-dicyclohexylamine, N, N-dimethyl-aniline, N, N- Dimethyl-benzylamine, pyridine, 2-methyl, 3-methyl, 4-methyl, 2,4-dimethyl, 2,6-dimethyl, 3,4-dimethyl and 3,5- Dimethyl-pyridine, 5-ethyl-2-methyl-pyridine, 4-dimethylamino-pyridine, N-methyl-piperidine, 1,4-diazabicyclo [2,2,2] octane (DABCO), 1,5- Diazabicyclo [4,3,0] non-5-ene (DBN), or 1,8-diazabicyclo [5,4,0] undec-7-ene

(DBU).

Inert organic solvents are particularly suitable as diluents for carrying out processes (a) and (b) according to the invention. These include in particular aliphatic, alicyclic or aromatic, optionally halogenated

Hydrocarbons, such as gasoline, benzene, toluene, xylene, chlorobenzene, dichlorobenzene, petroleum ether, hexane, cyclohexane, dichloromethane, chloroform, tetrahydrofuran chlorinated carbon; Ethers, such as diethyl ether, diisopropyl ether, dioxane, tetrahydrofuran or ethylene glycol dimethyl or diethyl ether; Ketones, such as acetone, butanone or methyl isobutyl ketone; Nitriles such as acetonitrile, propionitrile or butyronitrile; Amides such as N, N-dimethylformamide, N, N-dimethylacetamide, N-methylformanilide, N-methylpyrrolidone or hexamethylphosphoric triamide; Esters, such as methyl acetate or ethyl acetate, and sulfoxides or sulfones, such as dimethyl sulfoxide or tetramethylene sulfone (“sulfolane”) -

The reaction temperatures can be varied within a substantial range when carrying out processes (a) and (b) according to the invention. In general, temperatures between 0 ° C and 200 ° C, preferably between 10 ° C and 150 ° C.

Processes (a) and (b) according to the invention are generally carried out under normal pressure. However, it is also possible to carry out the processes according to the invention under elevated or reduced pressure - generally between 0.1 bar and 10 bar.

To carry out the processes according to the invention, the starting materials are generally used in approximately equimolar amounts. However, it is also possible to use one of the components in a large excess. The reaction is generally carried out in a suitable diluent in the presence of a reaction auxiliary and the reaction mixture is generally stirred for several hours at the required temperature. The processing is carried out in each case by customary methods (cf. the production examples).

The active compounds according to the invention can be used as defoliants, desiccants, haulm killers and in particular as weed killers. 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 depends essentially on the amount used. The active compounds according to the invention can be used, for example, in the following plants:

Dicotyledon 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, Dutilon, Emo Viola, galeopsis, papaver, centaurea, trifolium, ranunculus, taraxacum.

Dicotyledon cultures of the genera: Gossypium, Glycine, Beta, Daucus, Phaseolus, Pisum, Solanum, Linum, Ipomoea, Vicia, Nicotiana, Lycopersicon, Arachis, Brassica, Lactuca, Cucumis, Cucurbita.

Monocotyledon weeds of the genera: Echinochloa, Setaria, Panicum, Digitaria, Phleum, Poa, Festuca, Eleusine, Brachiaria, Lolium, Bromus, Avena, Cyperus, Sorghum, Agropyron, Cynodon, Monochoria, Fimbristylis, Sagittaria, Iochasumirumum, Scalumumum, Scalumumum , Sphenoclea, Dactyloctenium, Agrostis, Alopecurus, Apera.

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 limited to these

Limited genera, but extends in the same way to other plants.

Depending on the concentration, the compounds are suitable for total weed control, for example on industrial and track systems and on paths and squares with and without tree cover. The compounds for weed control in permanent crops, for example forest, ornamental wood, fruit, wine, citrus, nut, Banana, coffee, tea, gum, oil palm, cocoa, berry fruit and hop plants are used on ornamental and sports turf and pasture land and for selective weed control in annual crops.

The compounds of formula (I) according to the invention are particularly suitable for the selective control of monocotyledon and dicotyledon weeds in monocotyledon and dicotyledon crops both in the pre-emergence and in the post-emergence process.

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 very fine encapsulations in polymeric substances.

These formulations are prepared in a known manner, e.g. B. by mixing the active ingredients with extenders, that is liquid solvents and / or solid

Carriers, where appropriate using surface-active agents, that is to say emulsifiers and / or dispersants and / or foam-generating agents.

If water is used as an extender, e.g. organic solvents can also be used as auxiliary solvents. The following are essentially suitable as liquid solvents: aromatics, such as xylene, toluene, or alkylnaphthalenes, chlorinated aromatics and chlorinated aliphatic hydrocarbons, such as chlorobenzenes, chlorethylenes or methylene chloride, aliphatic hydrocarbons, such as cyclohexane or paraffins, e.g. Petroleum fractions, mineral and vegetable oils, alcohols such as butanol or glycol as well as their ethers and esters, ketones such as

Acetone, methyl ethyl ketone, methyl isobutyl ketone or cyclohexanone, strongly polar solvents such as dimethylformamide and dimethyl sulfoxide, and water.

Possible solid carriers are: e.g. Ammonium salts and natural rock powders, such as kaolins, clays, talc, chalk, quartz, attapulgite, montmorillonite or diatomaceous earth and synthetic rock powders, such as highly disperse

Silicic acid, aluminum oxide and silicates, come as solid carriers for granules e.g. broken and fractionated natural rocks such as calcite, marble, pumice, sepiolite, dolomite and synthetic granules from inorganic and organic flours as well as granules from organic material such as sawdust, coconut shells, corn cobs and tobacco stems, are emulsifying and / or foam-generating agents in question. For example, nonionic and anionic emulsifiers, such as polyoxyethylene fatty acid esters, polyoxyethylene fatty alcohol ethers, for example alkyl aryl polyglycol ethers, alkyl sulfonates, alkyl sulfates, aryl sulfonates and protein hydrolyzates, and dispersants are, for example, lignin sulfite liquors and methyl cellulose

Adhesives such as carboxymethyl cellulose, natural and synthetic polymers in the form of powders, granules or latices, such as gum arabic, polyvinyl alcohol, polyvinyl acetate, and natural phospholipids, such as cephalins and lecithins and synthetic phospholipids, can be used in the formulations. Other additives can be mineral and vegetable oils

Dyes such as inorganic pigments, for example iron oxide, titanium oxide, ferrocyan blue and organic dyes such as alizarin, azo and metal phthalocyanine dyes and trace nutrients such as salts of iron, manganese, boron, copper, cobalt, molybdenum and zinc can be used

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

The active compounds according to the invention, as such or in their formulations, can also be used in a mixture with known herbicides for combating weeds, finished formulations or tank mixes being possible

Known herbicides are suitable for the mixtures, for example acetochlor, acifluorfen (sodium), aclonifen, alachlor, alloxydim (sodium),

Ametryne, Amidochlor, Amidosulfüron, Asulam, Atrazine, Azimsulfüron, Benazolin, Benfüresate, Bensulfüron (-methyl), Bentazon, Benzofenap, Benzoylprop (-ethyl), Bi- alaphos, bifenox, bromobutide, bromofenoxim, bromoxynil, butachlor, butylates, cafenstrole, carbetamides, chlomethoxyfen, chloramben, chloridazone, chlorimuron (- ethyl), chlornitrofen, chlorsulfüron, chlortoluron, cinmethylin, clinosulfuronine, clinosulfonone Clopyralid, clopyrasulfon, chlorosulam (methyl), cumyluron, cyanazines, cycloates, cyclosulfamuron, cycloxydim,

Cyhalofop (-butyl), 2,4-D, 2,4-DB, 2,4-DP, Desmedipham, Diallate, Dicamba, Diclofop (-methyl), Difenzoquat, Diflufenican, Dimefüron, Dimepiperate, Dimethachlor, Di- methametryn, dimethenamid, dinitramine, diphenamide, diquat, dithiopyr, diuron, dymron, EPTC, esprocarb, ethalfluralin, ethametsulfüron (-methyl), ethofümesate, ethoxyfen, etobenzanid, fenoxaprop (-ethyl), flamprop (-isopropyliso, flamprop (-isopropyliso) - propyl-L), flamprop (-methyl), flazasulfüron, fluazifop (-butyl), flumetsulam, flumiclorac (-pentyl), flumioxazin, flumipropyn, fluometuron, fluorochloridone, fluoroglycofen (-ethyl), flupoxam, flupropacil, Flurenol, Fluridone, Fluroxypyr, Flurprimidol, Flurtamone, Fomesafen, Glufosinate (-ammonium), Glyphosate (-isopropyl-ammonium), Halosafen, Haloxyfop (-ethoxyethyl), Hexazinone, Imazamethabenz (- methyl), Imazamethapyr, Imazyroxaz, Imazyramox, Imazethapyr, imazosulfon, ioxynil, isopropalin, isoproturon, isoxaben, isoxaflutole, isoxapyrifop, lactofen, lenacil, linuron, MCPA, MCPP, Mefenacet, Metamitron, Metazachlor, Methabenzthiazuron, Metobenzuron, Metobromuron, Metolachlor, Metosulam, Metoxuron, Metribuzin, Metsulfüron (-methyl), Molinate, Monolinuron, Naproanilide,

Napropamide, Neburon, Nicflulfazon, Orbencarb, Oryzalin, Oxadiazon, Oxyfluorfen, Paraquat, Pendimethalin, Phenmedipham, Pretilachlor, Primisulfüron (-methyl), Prometryn, Propachlor, Propsilon, Pysulfonafide, Prosulfon (-ethyl), Pyrazoxyfen, Pyributicarb, Pyridate, Pyrithiobac (-sodium), Quinchlorac, Quinmerac, Quizalofop (- ethyl), Quizalofop (-p-tefüryl), Rimsulfüron, Sethoxydim, Simazine, Simetryn, Sulcotrione, Sulfentraonzone, Sulfom (-methyl), sulfosate, tebutam, tebuthiuron, terbuthylazine, terbutryn, thenylchlor, thiafluamide, thiazopyr, thidiazimin, thifene-sulfüron (-methyl), thiobencarb, tiocarbazil, tralkoxydim, triallate, triasulfuronl-methylronyl, triben , Tridiphane, trifluralin and triflusulfüron. A mixture with other known active compounds, such as fungicides, insecticides, acaricides, nematicides, bird repellants, plant nutrients and agents which improve soil structure, is also possible.

The active compounds can be used as such, in the form of their formulations or in the use forms prepared therefrom by further dilution, such as ready-to-use solutions, suspensions, emulsions, powders, pastes and granules. They are used in the usual way, e.g. by pouring, spraying, spraying, sprinkling.

The active compounds according to the invention can be applied both before and after emergence of the plants. They can also be worked into the soil before sowing.

The amount of active ingredient used can vary over a wide range. It essentially depends on the type of effect desired. In general, the application rates are between 1 g and 10 kg of active ingredient per hectare of soil, preferably between 5 g and 5 kg per ha.

The preparation and use of the active compounds according to the invention can be seen from the examples below.

Preparation Examples:

example 1

(Method (a))

A mixture of 12 g (40 mmol) of 3-amino-4,4,4-trifluoro-crotonic acid ethyl ester, 11 g of potassium carbonate and 100 ml of N-methyl-pyrrolidone is stirred at 100 ° C. for one hour. Then 9.4 g (40 mmol) of N- [2- (4-chlorophenyl) ethyl] O-ethyl carbamate are added and the reaction mixture is 8 hours at 140 ° C and then 18 hours at room temperature (about 20 ° C) stirred. After stirring with water, the mixture is shaken with ethyl acetate, the organic phase is separated off and, after acidification with 2N hydrochloric acid, the aqueous phase is shaken again with ethyl acetate. The combined organic phases are washed with water, dried with sodium sulfate and filtered. The solvent is carefully distilled off from the filtrate in a water jet vacuum.

3.0 g (24% of theory) of l- [2- (4-chlorophenyl) ethyl] -4-trifluoromethyl-3,6-dihydro-2,6-dioxo-l (2H) pyrimidine are obtained as an amorphous residue.

! H NMR (DMSO-D6, δ): 6.23 ppm. Example 2

(Method (b))

A mixture of 1.0 g (3.1 mmol) of l- [2- (4-chlorophenyl) ethyl] -4-trifluoromethyl-3,6-dihydro-2,6-dioxo-l (2H) - pyrimidine, 0.4 g (3.1 mmol) of dimethyl sulfate, 0.8 g of potassium carbonate and 100 ml of acetone are stirred under reflux for 7 hours and then for a further 48 hours at room temperature (approx. 20 ° C.). It is then concentrated in a water-jet vacuum, the residue is stirred with water and the crystalline product is isolated by suction.

0.8 g (78% of theory) of 1- [2- (4-chlorophenyl) ethyl] -3-methyl-4-trifluoromethyl-3,6-dihydro-2,6-dioxo- l (2H) -pyrimidine, melting point 127 ° C.

Example 3

(Method (b))

A mixture of 1.0 g (3.1 mmol) of l- [2- (4-chlorophenyl) ethyl] -4-trifluoromethyl-3,6-dihydro-2,6-dioxo-l (2H) - pyrimidine, 0.27 g of sodium hydrogen carbonate and 100 ml of N, N-dimethylformamide is stirred for 30 minutes at room temperature (approx. 30 ° C). After the addition of 0.4 g (3.1 mmol) of l-aminooxy-2,4-dinitro-benzene, the re- action mixture 5 hours and after adding a further 0.4 g of l-aminooxy-2,4-dinitro-benzene stirred for a further 48 hours at room temperature. After stirring with water, the mixture is shaken with ethyl acetate, the organic phase is separated off and, after acidification with 2N hydrochloric acid, the aqueous phase is shaken again with ethyl acetate. The combined organic phases are washed with water, dried with sodium sulfate and filtered. The filtrate is concentrated in a water jet vacuum, the residue is digested with diisopropyl ether and the crystalline product is isolated by suction.

0.75 g (73% of theory) of 3-amino-1- [2- (4-chlorophenyl) ethyl] -4-trifluoromethyl-3,6-dihydro-2,6-dioxo- 1 (2H) -pyrimidine, melting point 146 ° C.

Analogously to preparation examples 1 to 3 and in accordance with the general description of the preparation processes according to the invention, the compounds of the formula (I) listed in Table 1 below can also be prepared, for example.

Table 1 Examples of the compounds of the formula (I)

Starting materials of the formula (HI)

Example, m-l.

A mixture of 7.8 g (50 mmol) of 2- (4-chlorophenyl) ethylamine, 6.0 g (55 mmol) of ethyl chloroformate, 7.9 g of pyridine and 100 ml of methylene chloride is stirred for 18 hours at room temperature ( about 20 ° C) stirred. The mixture is then acidified with 2N hydrochloric acid, the organic phase is separated off and the aqueous phase is subsequently extracted with methylene chloride. The combined organic phases are dried with sodium sulfate and filtered. The solvent is carefully distilled off from the filtrate in a water jet vacuum.

11.0 g (96% of theory) of N- [2- (4-chlorophenyl) ethyl] -O-ethyl-carbamate are obtained as an amorphous residue.

Analogously to Example (III-1), for example, the compounds of the general formula (III) listed in Table 2 below can also be prepared.

Table 2: Examples of the compounds of the formula (III)

Examples of use:

Example A

Pre-emergence test

Solvent 5 parts by weight of acetone

Emulsifier 1 part by weight of alkylaryl polyglycol ether

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

Seeds of the test plants are sown in normal soil. After about 24 hours, the soil is sprayed with the active compound preparation in such a way that the desired amounts of active compound are applied per unit area. The concentration of the spray mixture is chosen so that the desired amounts are applied in 1,000 l of water / ha Active ingredient quantities are applied

After three weeks, the degree of damage to the plants is rated in% damage compared to the development of the untreated control

It mean-

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

In this test, for example, the compound according to Preparation Example 12, at an application rate of 1000 g / ha, shows good compatibility with crop plants, such as maize, and a strong action against weeds such as Setaria (100%), Amaranthus (100%) and Xanthium (90%) Example B

Post emergence test

Solvent: 5 parts by weight of acetone

Emulsifier: 1 part by weight of alkylaryl polyglycol ether

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

Test plants with a height of 5-15 cm are sprayed with the active substance preparation in such a way that the desired amounts of active substance are applied per unit area. The concentration of the spray liquor is chosen so that in

1000 1 water / ha the desired amounts of active ingredient are applied.

After three weeks, the degree of damage to the plants is rated in% damage compared to the development of the untreated control.

It means:

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

In this test, for example, the compounds according to Preparation Examples 3, 12 and 13 show good compatibility with crop plants, such as e.g. Maize and strong action against weeds such as Setaria (80%), Abutilon (100%), Amaranthus (100%) and Galium (100%).

Claims

claims

1. Substituted arylalkyl uracils of the general formula (I)

in which

A represents straight-chain or branched alkanediyl having two or more carbon atoms,

Ar represents in each case optionally substituted phenyl or naphthyl,

R ^{1 represents} hydrogen, amino or optionally substituted alkyl,

R ^{2 represents} halogen substituted alkyl and

R ^{3 represents} hydrogen, halogen or alkyl.

2. Substituted arylalkyluracils of general formula (I) according to claim 1, characterized in that

A stands for straight-chain or branched alkanediyl with two to four carbon atoms,

Ar for each optionally by amino, nitro, cyano, carboxy, carbamoyl, thiocarbamoyl, fluorine, chlorine, bromine, CjA ^ alkyl (which is is optionally substituted by fluorine and / or chlorine) and / or Ci - C4-alkoxy (which is optionally substituted by fluorine and / or chlorine) substituted phenyl or naphthyl,

R ^{1 represents} hydrogen, amino or alkyl having 1 to 4 carbon atoms which is optionally substituted by cyano, fluorine or chlorine,

3. Substituted arylalkyluracils of the general formula (I) according to claim 1, characterized in that

A for ethane-l, l-diyl ("ethylidene"), ethane-l, 2-diyl ("dimethylene"), propane-l, l-diyl ("propylidene"), propane-l, 2-diyl or propane -l, 3-diyl ("trimethylene"),

R ^{1 represents} hydrogen, amino, methyl or ethyl,

R ² represents methyl or ethyl substituted by fluorine and / or chlorine and

R ^{3 represents} hydrogen, chlorine, bromine or methyl. Process for the preparation of the substituted arylalkyl uracils of the general formula (I),

in which

Ar represents in each case optionally substituted phenyl or naphthyl,

R ^{1 represents} hydrogen, amino or optionally substituted alkyl,

R ^{2 represents} halogen substituted alkyl and

R ^{3 represents} hydrogen, halogen or alkyl,

characterized in that one

(a) aminoalkenates of the general formula (II)

in which R ² and R ^{3 have} the meanings given above and

A ^{1 represents} alkyl, aryl or arylalkyl,

with arylalkyl urethanes (arylalkyl carbamates) of the general formula (III)

H

in which

A and Ar have the meanings given above and

A ^{2 represents} alkyl, aryl or arylalkyl,

implements

or that one

(b) substituted arylalkyluracils of the general formula (Ia),

in which

A, Ar, R ² and R ^{3 have} the meanings given above, with l-aminooxy-2,

4-dinitro-benzene or with alkylating agents of the general formula (IV)

XA ³ (IV)

in which

A ^{3 represents} optionally substituted alkyl and

X represents halogen or the grouping -O-SO ₂ -OA ³ .

5. Herbicidal agents, characterized in that they contain at least one substituted arylalkyluracil of the formula (I) according to claim 1.

6. A method for controlling unwanted plants, characterized in that substituted arylalkyluracils of the formula (I) according to Claim 1 are allowed to act on undesired plants and / or their habitat.

7. Use of substituted arylalkyluracils of formula (I) according to claim 1 for combating undesirable plants.

8. A process for the preparation of herbicidal compositions, characterized in that substituted arylalkyluracils of the formula (I) according to Claim 1 are mixed with extenders and / or surface-active substances.

9. Substituted arylalkyl uracils of the general formula (Ia),

in which

A for straight-chain or branched alkanediyl with two or more

Carbon atoms,

Ar represents in each case optionally substituted phenyl or naphthyl,

R ^{2 represents} halogen substituted alkyl and

R ^{3 represents} hydrogen, halogen or alkyl.