Ureas.

The present invention relates to new N- (2-nitrophenyl) -N-pyrimidin-2-ylureas with herbicidal and plant growth-regulating action, agrochemical compositions which contain these substances as active compounds, the use of the new ureas for combating weeds or for regulation of plant growth and processes for producing the new compounds. The invention also relates to new intermediates and processes for their production.

(Pyrimidin-2-yl) -2-nitroanilines have become known from the patent specification DD-151 404 and the European patent application EP-AO 172 786. These compounds are fungicidally active. In contrast, it was surprisingly found that N-pyrimidin-2-yl-N-2-nitrophenylureas have herbicidal or plant growth regulatory activity.

The invention thus relates to ureas of the formula<chemistry id="chem0001" num="0001"><img file="EP0264348A2_D0001.tif" /></chemistry> wherein R¹ and R² independently of one another hydrogen, halogen, C₁-C₆-alkyl, C₁-C₄-haloalkyl, C₁-C₄-alkoxy, C₁-C₄-haloalkoxy, C₁-C₄-alkoxy carbonyl, C₁-C₄-alkoxy- (C₁-C₄ ) alkyl, nitro or cyano, R³ and R⁴ independently of one another hydrogen, halogen, cyano, OH, SH, C₁-C₆-alkyl, C₁-C₄-haloalkyl, C₁-C₄-alkoxy, C₁-C₄-haloalkoxy, C₁-C₄-alkylthio, C₁-C₄-haloalkylthio , Amino, mono-C₁-C₄-alkylamino, di-C₁-C₄-alkylamino, C₁-C₄-alkoxycarbonyl or C₁-C₄-alkoxy- (C₁-C₄) -alkyl, and their salts and addition compounds with acids, bases and complexing agents.

Within the scope of the invention disclosed here, the generic terms given include, for example, the following specific individual substituents, this list not being a limitation of the invention:

Alkyl includes the straight-chain or branched C₁-C₆ alkyls, such as methyl, ethyl, n-propyl, iso-propyl, n-butyl, sec-butyl, tert-butyl, iso-butyl, the isomeric pentyls such as tert-pentyl (1,1-dimethylpropyl), isopentyl (1-ethylpropyl), and the isomeric hexyl radicals. The C₁-C₃ alkyl radicals are preferred.

Halogen is fluorine, chlorine, bromine and iodine. Fluorine, chlorine and bromine are preferred.

Haloalkyl means the completely or partially identical or different halogen-substituted alkyls according to the respective definition, such as 2,2,2-trifluoroethyl, 1,1,1,3,3,3-hexafluoroprop-2-yl, trifluoromethyl or difluoromethyl .

As C₁-C₄ alkoxycarbonyl radicals include methoxycarbonyl, ethoxycarbonyl and the isomeric propyloxycarbonyls and butyloxycarbonyls.

Alkoxy are within the scope of the respective definition of isomeric alkyloxy radicals, primarily methoxy and ethoxy.

Haloalkoxy and haloalkylthio are within the scope of the respective definition, the isomeric one or more identical or different halogen-substituted alkyl radicals, such as trifluoromethoxy, 2,2,2-trifluoroethoxy, trifluoromethylthio, 2,2,3,3,3-pentafluoropropyloxy or 1,1 , 2,2-tetrafluoroethoxy.

Examples of alkoxyalkyl radicals include: 2-ethoxyethyl, 2-methoxyethyl, 3-methoxypropyl, 2-methoxy-1-methylethyl and methoxymethyl.

Di-C₁-C₄-alkylamino is a group substituted by the same or different alkyl radicals, such as dimethylamino, diethylamino, methylethylamino.

In the other substituents, which are composed of several basic elements, the partial elements can be freely selected within the definition and have the above meaning.

Of particular note are compounds of the formula I in which R¹ and R² independently of one another hydrogen, halogen, C₁-C₃-alkyl, C₁-C₃-haloalkyl, C₁-C₃-alkoxy, C₁-C₃-alkoxycarbonyl, nitro, cyano or C₁-C₃-alkoxy- (C₁-C₃) alkyl , R³ and R⁴ independently of one another hydrogen, halogen, C₁-C₃-alkyl, C₁-C₃-haloalkyl, C₁-C₄-alkoxy, C₁-C₃-haloalkoxy, C₁-C₄-alkylthio, amino, mono-C₁-C₃-alkylamino, Di -C₁-C₃-alkylamino, cyano, C₁-C₄-alkoxycarbonyl or C₁-C₄-alkoxy- (C₁-C₄) alkyl means.

Preferred compounds of the formula I are those in which R¹ is hydrogen, halogen, C₁-C₃-alkyl, C₁-C₃-haloalkyl, C₁-C₃-alkoxy or C₁-C₃-alkoxycarbonyl, R² is hydrogen, halogen, C₁-C₃-alkyl, nitro or cyano, R³ and R⁴ independently of one another hydrogen, halogen, C₁-C₃-alkyl, C₁-C₃-haloalkyl, C₁-C₄-alkoxy, C₁-C₃-haloalkoxy, C₁-C₄-alkylthio, amino, mono-C₁-C₃-alkylamino, Di -C₁-C₃-alkylamino, cyano, C₁-C₄-alkoxycarbonyl or C₁-C₃-alkoxy- (C₁-C₃) alkyl means.

In particular, the invention relates to compounds of the formula I in which R¹ is hydrogen, chlorine, methyl, trifluoromethyl, methoxy or ethoxycarbonyl, R² is hydrogen, chlorine, methyl or nitro, R³ is hydrogen, fluorine, chlorine, methyl, ethyl, propyl, trifluoromethyl, methoxy, ethoxy, difluromethoxy, 1,1,2,2-tetrafluoroethoxy, dimethylamino, ethoxycarbonyl or C₁-C₄-alkylthio, R⁴ hydrogen, fluorine, chlorine, bromine, methyl, methoxymethyl, methoxyethyl, C₁-C₄-alkoxy, 1,1,2,2-tetrafluoroethoxy, dimethylamino, Difluoromethoxy, fluoromethoxy, trifluoromethyl or C₁-C₄ alkylthio means.

Compounds of the formula I in which R¹ is hydrogen, methyl, methoxy, trifluoromethyl or Cl, R² is hydrogen or methyl, R³ is methyl, ethyl, propyl, chlorine, trifluoromethyl, 1,1,2,2-tetrafluoroethoxy, methylthio, propylthio, ethoxy or methoxy, R⁴ fluorine, chlorine, methyl, methoxy, methoxymethyl, difluoromethoxy, fluoromethoxy, trifluoromethyl or bromine means.

With regard to the position of the substituents R 1 and R 2, preference is given to those compounds of the formula I in which one or both substituents are bonded in positions 5 and 6 of the phenyl ring.

Furthermore, particular preference is given to compounds of the formula I in which R¹ and R² are hydrogen, R³-methoxy or methyl and R⁴ is chlorine, methyl, methoxy, methoxymethyl, trifluoromethyl or difluoromethoxy.

The compounds of formula I can be prepared by<ul id="ul0001" list-style="none"><li>a) an aniline of formula II with phosgene to a carbamine chloride of formula III and this in a second step with NH₃<chemistry id="chem0002" num="0002"><img file="EP0264348A2_D0002.tif" /></chemistry> a urea of ​​the formula I or</li><li>b) reacting an aniline of the formula II with halogen sulfonyl isocyanate to give a halogen sulfonylurea of ​​the formula IV<chemistry id="chem0003" num="0003"><img file="EP0264348A2_D0003.tif" /></chemistry> and hydrolyzed this in a second stage or directly to a compound of the formula I, where Y represents a group which can be split off under the reaction conditions, such as halogen, preferably chlorine, or</li><li>c) rearranged a sulfonylurea of ​​formula V under the action of an aqueous base to a urea of ​​formula I.<chemistry id="chem0004" num="0004"><img file="EP0264348A2_D0004.tif" /></chemistry> preferably NaOH / water or KOH / water are used as aqueous bases.</li></ul>

The reactions II → III, III → I and IV → I proceeding with elimination of hydrogen halide or HY elimination are preferably carried out using acid-binding agents (bases).

Organic or inorganic bases are suitable as such, for example tertiary amines such as trialkylamines (trimethylamine, triethylamine, tripropylamine etc.), pyridines (pyridine, 4-dimethylaminopyridine, 4-pyrrolidylaminopyridine etc.), alcoholates such as potassium tert-butoxide, Sodium methylate or ethylate. The aforementioned reactions as well as the reaction V → I can also be carried out under phases transfer conditions with bases according to methods known per se (Lit. Dehmlow &amp; Dehmlow, Phase Transfer Catalysis Verlag Chemie, Weinheim, 1983).

In the case of process variants a) and b), one or more inert solvents or diluents may be present, unless expressly specified in detail. For example, aliphatic and aromatic hydrocarbons such as benzene, toluene, xylenes, petroleum ether; halogenated hydrocarbons such as chlorobenzene, methylene chloride, ethylene chloride, chloroform, carbon tetrachloride, tetrachlorethylene; Ethers and ethereal compounds such as dialkyl ether (diethyl ether, diisopropyl ether, tert-butyl methyl ether, etc.), anisole, dioxane, tetrahydrofuran; Nitriles such as acetonitrile, propionitrile; N, N-dialkylated amides such as dimethylformamide; Dimethyl sulfoxide; Ketones such as acetone, diethyl ketone, methyl ethyl ketone and mixtures of such solvents with one another.

Some of the 2-nitroanilines of the formula II are known from EP-A 172 786. Like the new carbamoyl chlorides of the formula III and the new ureas of the formula IV, they are valuable intermediates for the synthesis of the herbicidally active ureas I.

The invention thus also relates to the new compounds of the formula<chemistry id="chem0005" num="0005"><img file="EP0264348A2_D0005.tif" /></chemistry> wherein R¹ and R² independently of one another are hydrogen, halogen, C₁-C₆-alkyl, C₁-C₄-haloalkyl, C₁-C₄-alkoxy, C₁-C₄-haloalkoxy, C₁-C₄-alkoxycarbonyl, C₁-C₄-alkoxy- (C₁-C₄) alkyl, nitro or cyano, R³ and R⁴ independently of one another hydrogen, halogen, cyano, OH, SH, C₁-C₆-alkyl, C₁-C₄-haloalkyl, C₁-C₄-alkoxy, C₁-C₄-haloalkoxy, C₁-C₄-alkylthio, C₁-C₄-haloalkylthio , Amino, mono-C₁-C₄-alkylamino, di-C₁-C₄-alkylamino, C₁-C₄-alkoxycarbonyl or C₁-C₄-alkoxy- (C₁-C₄) alkyl means with the proviso that when R¹ is 4-NO₂ and R² is 6-CF₃, R³ and R⁴ are not F, Cl, Br, C₁-C₄-alkyl, C₁-C₃-alkoxy, C₁-C₄-alkyl thio, cyano , CCl₃, CF₃, OCH₂OC₂H₅, OCH₂F, CH₂OCH₃ or OCH₂CF₃ and when R¹ is 4-CF₃ and R² is 6-NO₂ the following pairs of meanings of R³ and R⁴ are not included: Cl, Cl; n-C₆H₁₃, Cl; Br, Br; CN, CH₃; F, F; CH₃, CH₃; Cl, SCH₃; Cl, OCH₃; Cl, OCH₂CF₃; Cl, CH₂Cl and Cl, CH₂F; and with the proviso that R¹ and R² do not together represent hydrogen if R³ and R⁴ together represent CH₃.

The invention further relates to compounds of the formula<chemistry id="chem0006" num="0006"><img file="EP0264348A2_D0006.tif" /></chemistry> wherein R¹ and R² independently of one another are hydrogen, halogen, C₁-C₆-alkyl, C₁-C₄-haloalkyl, C₁-C₄-alkoxy, C₁-C₄-haloalkoxy, C₁-C₄-alkoxycarbonyl, C₁-C₄-alkoxy- (C₁-C₄) alkyl, nitro or cyano, R³ and R⁴ independently of one another hydrogen, halogen, cyano, C₁-C₆-alkyl, C₁-C₄-haloalkyl, C₁-C₄-alkoxy, C₁-C₄-haloalkoxy, C₁-C₄-alkylthio, C₁-C₄-haloalkylthio, amino, mono -C₁-C₄-alkylamino, di-C₁-C₄-alkylamino, C₁-C₄-alkoxycarbonyl or C₁-C₄-alkoxy- (C₁-C₄) alkyl means and ureas of the formula<chemistry id="chem0007" num="0007"><img file="EP0264348A2_D0007.tif" /></chemistry> wherein R¹ and R² independently of one another hydrogen, halogen, C₁-C₆-alkyl, C₁-C₄-haloalkyl, C₁-C₄-alkoxy, C₁-C₄-haloalkoxy, C₁-C₄-alkoxy carbonyl, C₁-C₄-alkoxy- (C₁-C₄ ) alkyl, nitro or cyano, R³ and R⁴ independently of one another hydrogen, halogen, cyano, C₁-C₆-alkyl, C₁-C₄-haloalkyl, C₁-C₄-alkoxy, C₁-C₄-haloalkoxy, C₁-C₄-alkylthio, C₁-C₄-haloalkylthio, amino, mono -C₁-C₄-alkylamino, di-C₁-C₄-alkylamino, C₁-C₄-alkoxycarbonyl or C₁-C₄-alkoxy- (C₁-C₄) alkyl Y halogen, C₁-C₄ alkoxy or phenoxy means.

The compounds of the formula III and IV are intermediates of processes a) and b) and can be prepared as described there from the corresponding 2-nitroanilines of the formula II.

The new 2-nitroanilines of the formula II can be prepared analogously to processes known from the literature, for example by:<ul id="ul0002" list-style="none"><li>aa) reaction of guanidines of the formula VI with 1,3-dicarbonyl compounds of the formula VII<chemistry id="chem0008" num="0008"><img file="EP0264348A2_D0008.tif" /></chemistry> wherein the condensation reaction is carried out, if desired, in the presence of water-binding agents (Lit: DJ Brown in "The Chemistry of Heterocyclic Compounds" Vol. VI 1962, Interscience Publ. New York) or</li><li>bb) by reacting a halogenobenzene of the formula VIII with a 2-aminopyrimidine of the formula IX<chemistry id="chem0009" num="0009"><img file="EP0264348A2_D0009.tif" /></chemistry> wherein R¹ and R² are preferably bound in the 4 or 6-position of the phenyl system (in II) and stand for an electron-withdrawing group (Lit. EP-AO 172 786). or</li><li>cc) by degradation of a sulfonylurea of ​​the formula V under the action of an aqueous base<chemistry id="chem0010" num="0010"><img file="EP0264348A2_D0010.tif" /></chemistry> at elevated temperature.</li></ul>

The invention further relates to herbicidal and plant growth regulating compositions comprising a compound of the formula I together with suitable auxiliaries and / or carriers.

The active compounds of the formula I are generally used successfully with application rates of 0.005 to 5 kg / ha, in particular 0.1 to 3 kg / ha. The dosage required for the desired effect can be determined by experiment. It depends on the type of action, the stage of development of the crop and weed, and on the application (place, time, method) and, depending on these parameters, can vary within wide ranges.

At lower application rates, the compounds of the formula I are distinguished by growth-inhibiting and herbicidal properties which make them excellent for use in crops of useful plants, in particular in cereals, cotton, soybeans, corn and rice.

The compounds of formula I also have plant growth regulatory properties. Both monocots and dicots are influenced in their growth.

An inhibition of vegetative growth allows a denser cultivation of the crop in many crop plants, so that an additional yield, based on the soil area, can be achieved.

Another mechanism of increasing yield with growth regulators is based on the fact that the nutrients benefit flower and fruit formation to a greater extent, while vegetative growth is restricted.

When larger amounts are applied, weeds and grasses are damaged in their development so that they die.

The invention also relates to herbicidal and plant growth regulating compositions which comprise an active ingredient of the formula I, and to processes for pre- and post-emergent weed control and for influencing plant growth in monocotyledonous and dicotyledonous plants, in particular grasses, tropical soil coverers and poultry shoots.

The compounds of the formula I are used in unchanged form or, preferably, as agents together with the auxiliaries customary in formulation technology and are therefore, for example, emulsion concentrates, directly sprayable or dilutable solutions, diluted emulsions, wettable powders, soluble powders, dusts, granules, and also encapsulations in eg polymeric materials processed in a known manner. The methods of application such as spraying, atomizing, dusting, scattering or pouring are chosen in the same way as the type of agent, in accordance with the intended goals and the prevailing conditions.

The formulations, ie the agents, preparations or compositions comprising the active ingredient of the formula I and, if appropriate, a solid or liquid additive, are prepared in a known manner, for example by intimately mixing and / or grinding the active ingredients with extenders, for example with solvents, solid carriers, and optionally surface-active compounds (surfactants).

Possible solvents are: Aromatic hydrocarbons, preferably the fractions C₈ to C₁₂, such as Xylene mixtures or substituted naphthalenes, phthalic esters such as dibutyl or dioctyl phthalate, aliphatic hydrocarbons such as cyclohexane or paraffins, alcohols and glycols and their ethers and esters such as ethanol, ethylene glycol, ethylene glycol monomethyl or ethyl ether, ketones such as cyclohexanone, strongly polar solvents such as N-methyl -2-pyrrolidone, dimethyl sulfoxide or dimethylformamide, and optionally epoxidized vegetable oils, such as epoxidized coconut oil or soybean oil; or water.

Natural rock flours, such as calcite, talc, kaolin, montmorillonite or attapulgite, are generally used as solid carriers, for example for dusts and dispersible powders. To improve the physical properties, highly disperse silica or highly disperse absorbent polymers can also be added. Porous types such as pumice, broken brick, sepiolite or bentonite come as granular, adsorptive granule carriers, and non-sorptive carrier materials, for example Calcite or sand in question. In addition, a large number of pregranulated materials of an inorganic or organic nature, such as, in particular, dolomite or comminuted plant residues can be used.

Depending on the nature of the active ingredient of the formula I to be formulated, suitable surface-active compounds are nonionic, cationic and / or anionic surfactants with good emulsifying, dispersing and wetting properties. Surfactants are also to be understood as mixtures of surfactants.

Suitable anionic surfactants can be both so-called water-soluble soaps and water-soluble synthetic surface-active compounds.

As soaps are the alkali, alkaline earth or optionally substituted ammonium salts of higher fatty acids (C₁₀-C₂₂), such as the Na or K salts of oleic or stearic acid, or of natural fatty acid mixtures obtained, for example, from coconut or tallow oil can be called. The fatty acid methyl taurine salts should also be mentioned.

However, so-called synthetic surfactants are used more frequently, in particular fatty sulfonates, fatty sulfates, sulfonated benzimidazole derivatives or alkylarylsulfonates.

The fatty sulfonates or sulfates are generally present as alkali, alkaline earth or optionally substituted ammonium salts and have an alkyl radical with 8 to 22 carbon atoms, alkyl also including the alkyl part of acyl radicals, for example the sodium or calcium salt lignin sulfonic acid, dodecyl sulfuric acid ester or a fatty alcohol sulfate mixture made from natural fatty acids. This subheading also includes the salts of sulfuric acid esters and sulphonic acids from fatty alcohol-ethylene oxide adducts. The sulfonated benzimidazole derivatives preferably contain 2-sulfonic acid groups and a fatty acid residue with 8-22 carbon atoms. Examples of alkylarylsulfonates are the sodium, calcium or triethanolamine salts of dodecylbenzenesulfonic acid, dibutylnaphthalenesulfonic acid or a naphthalenesulfonic acid / formaldehyde condensation product.

Corresponding phosphates, such as, for example, salts of the phosphoric acid ester of a p-nonylphenol (4-14) ethylene oxide adduct or phospholipids, are also suitable.

Suitable nonionic surfactants are primarily polyglycol ether derivatives of aliphatic or cycloaliphatic alcohols, saturated or unsaturated fatty acids and alkylphenols, which can contain 3 to 10 glycol ether groups and 8 to 20 carbon atoms in the (aliphatic) hydrocarbon radical and 6 to 18 carbon atoms in the alkyl radical of the alkylphenols .

Further suitable nonionic surfactants are the water-soluble polyethylene oxide adducts containing 20 to 250 ethylene glycol ether groups and 10 to 100 propylene glycol ether groups on polypropylene glycol, ethylenediaminopolypropylene glycol and alkylpolypropylene glycol with 1 to 10 carbon atoms in the alkyl chain. The compounds mentioned usually contain 1 to 5 ethylene glycol units per propylene glycol unit.

Examples of nonionic surfactants are nonylphenol polyethoxyethanols, castor oil polyglycol ethers, polypropylene-polyethylene oxide adducts, tributylphenoxypolyethoxyethanol, polyethylene glycol and octylphenoxypolyethoxyethanol.

Fatty acid esters of polyoxyethylene sorbitan such as polyoxyethylene sorbitan trioleate are also suitable.

The cationic surfactants are primarily quaternary ammonium salts which contain at least one alkyl radical having 8 to 22 carbon atoms as N substituents and have lower, optionally halogenated alkyl, benzyl or lower hydroxyalkyl radicals as further substituents. The salts are preferably in the form of halides, methyl sulfates or ethyl sulfates, for example stearyltrimethylammonium chloride or benzyldi (2-chloroethyl) ethylammonium bromide.

The surfactants commonly used in formulation technology are described in the following publications: "Mc Cutcheon's Detergents and Emulsifiers Annual" MC Publishing Corp., Ridgewood, New Jersey, 1979. Dr. Helmut Stache "Tensid Paperback" Carl Hanser Verlag, Munich / Vienna 1981.

The preparations generally contain 0.1 to 95%, in particular 0.1 to 80%, active ingredient of the formula I, 1 to 99.9% of a solid or liquid additive and 0 to 25%, in particular 0.1 to 25% of a surfactant.

In particular, preferred formulations are composed as follows: (% = weight percent)

<u style="single">Emulsifiable concentrates:</u>Active ingredient of formula I: 1 to 20% preferably 5 to 10% surfactant: 5 to 30%, preferably 10 to 20% liquid carrier: 50 to 94%, preferably 70 to 85%.

<u style="single">Dusts:</u>Active ingredient of formula I: 0.1 to 10%, preferably 0.1 to 1% solid carrier: 99.9 to 90%, preferably 99.9 to 99%.

<u style="single">Suspension concentrates:</u>Active ingredient of formula I: 5 to 75%, preferably 10 to 50% Water: 94 to 25%, preferably 90 to 30% surfactant: 1 to 40%, preferably 2 to 30%.

<u style="single">Wettable powders:</u>Active ingredient of formula I: 0.5 to 90%, preferably 1 to 80% surfactant: 0.5 to 20%, preferably 1 to 15% solid carrier: 5 to 95%, preferably 15 to 90%.

<u style="single">Granules:</u>Active ingredient of formula I: 0.5 to 30%, preferably 3 to 15% solid carrier: 99.5 to 70%, preferably 97 to 85%.

While concentrated agents are preferred as a commodity, the end user generally uses diluted agents. The use forms can be diluted down to 0.001% of active ingredient. The application rates are usually 0.005 to 5 kg AS / ha.

The agents can also contain other additives such as stabilizers, defoamers, viscosity regulators, binders, adhesives and fertilizers or other active ingredients to achieve special effects.

Manufacturing examples

The - uncorrected - melting points in the following production examples are given in ° C.

H 1.1.

Synthesis of N- (6-chloro-4-methylpyrimidin-2-yl) -N-2-nitrophenylurea

79.3 g (0.3 mol) of N- (6-chloro-4-methyl-pyrimidin-2-yl) -2-nitro-aniline are dissolved in 2.2 l of ethyl acetate at 60 °. The solution is cooled to 5 °, whereby yellow crystals precipitate. 56.6 g (0.4 mol) of chlorosulfonyl isocyanate are added and the mixture is then stirred at 5 ° for 15 min. Then 300 ml of cold water are poured in, the organic phase is separated off, dried with sodium sulfate and evaporated. The solid residue is triturated with a little ethyl acetate.

71.5 g (74.4%) of the title compound of the formula are isolated<chemistry id="chem0011" num="0011"><img file="EP0264348A2_D0011.tif" /></chemistry> (Compound No. 1.007) as crystals of mp 155 ° C).

H.1.2.

Synthesis of N- (6-chloro-4-methyl-pyrimidin-2-yl) -N-2-nitrophenylurea

18.6 g (0.05 mol) of 3- (6-chloro-4-methyl-pyrimidin-2-yl) -1- (2-nitrophenylsulfonyl) urea are suspended in 100 ml of water and 200 ml of chloroform. A solution of 3.2 g of sodium hydroxide in 350 ml of water is added dropwise at 25 ° within 4 hours. The 2-phase solution is stirred for 16 hours. Then the CHCl₃ phase is separated, dried with sodium sulfate and evaporated. The residue is recrystallized from chloroform.

3.3 g (21.4%) of the title compound of the formula are isolated<chemistry id="chem0012" num="0012"><img file="EP0264348A2_D0012.tif" /></chemistry> (Compound No. 1.007) as a Kirstalle with a melting point of 155 ° C.

Analogous to the production examples H.1. can the compounds of the formula listed below in Table 1<chemistry id="chem0013" num="0013"><img file="EP0264348A2_D0013.tif" /></chemistry> getting produced:<tables id="tabl0001" num="0001"><img file="EP0264348A2_D0014.tif" /></tables><tables id="tabl0002" num="0002"><img file="EP0264348A2_D0015.tif" /></tables><tables id="tabl0003" num="0003"><img file="EP0264348A2_D0016.tif" /></tables>

H. 2.1.

Synthesis of N- (6-chloro-4-methyl-pyrimidin-2-yl) -2-nitroaniline

24th g (0.064 mol) of 3- (6-chloro-4-methyl-pyrimidin-2-yl) -1- (2-nitrophenylsulfonyl) urea are suspended in 150 ml of water and 200 ml of chloroform. After the addition of 25 ml of 30% sodium hydroxide solution, the reaction mixture is stirred for 1 hour at 50-55 °, the chloroform phase is separated off and dried with sodium sulfate. After evaporation of the chloroform, 14.7 g (86.7% of theory) of the title compound of the formula are obtained<chemistry id="chem0014" num="0014"><img file="EP0264348A2_D0017.tif" /></chemistry> (Compound No. 2.007) as crystals of mp. 175 ° C.

H. 2.2.

Synthesis of N- (6-chloro-4-methyl-pyrimidin-2-yl) -2-nitroaniline

A mixture of 160 g (0.65 mol) of N- (6-hydroxy-4-methyl-pyrimidin-2-yl) -o-nitroaniline, 2 ml of N, N-dimethylformamide and 120 ml of phosphorus oxychloride are heated to reflux for 3 hours. After cooling, the black slurry is dissolved in chloroform and this solution is added dropwise to 1 liter of water. The temperature is kept at 35 ° by adding ice. After 1 hour the organic phase is separated off and the aqueous phase is washed with chloroform. Both chloroform solutions are dried together and evaporated. The black residue is dissolved in hot toluene, filtered and made to crystallize by adding hexane. 104.9 g (61%) of the title compound of the formula are obtained<chemistry id="chem0015" num="0015"><img file="EP0264348A2_D0018.tif" /></chemistry> (Compound No. 2.007) as a Kirstalle with mp. 175 ° C.

H. 2.3.

Synthesis of N- (6-hydroxy-4-methyl-pyrimidin-2-yl) -2-nitroaniline

121 g (0.5 mol) of 2-nitrophenyl guanidine carbonate, 100 g of ethyl acetoacetate and 200 ml of diethylene glycol dimethyl ether are first heated to 65 ° and after completion of the CO₂ evolution to 140 °. Allow ethanol and water to distill off. After 3 1/2 hours, the suspension is allowed to cool, water is added and the pH is adjusted to 4-5 with concentrated hydrochloric acid. The yellow precipitate is filtered off, washed with water and dried at 80 ° C. in vacuo. 80.3 g (65.2% of theory) of the title compound of the formula are obtained<chemistry id="chem0016" num="0016"><img file="EP0264348A2_D0019.tif" /></chemistry> (Compound No. 2.071) as crystals of mp 240-242 °.

Analogous to the production examples H.2. the compounds of the formula listed in Table 2 below<chemistry id="chem0017" num="0017"><img file="EP0264348A2_D0020.tif" /></chemistry> getting produced:<tables id="tabl0004" num="0004"><img file="EP0264348A2_D0021.tif" /></tables><tables id="tabl0005" num="0005"><img file="EP0264348A2_D0022.tif" /></tables><tables id="tabl0006" num="0006"><img file="EP0264348A2_D0023.tif" /></tables>

Biological examples

Example B1: Pre-emergent herbicide activity

Immediately after sowing the test plants in seed trays, the earth's surface is treated in the greenhouse with an aqueous spray mixture corresponding to an application rate of 4 kg of active substance / hectare. The seed pans are kept in the greenhouse at 22-25 ° C and 50-70% relative humidity.

After 3 weeks, the herbicidal activity is assessed using a nine-stage (1 = complete damage, 9 = no effect) rating scheme in comparison in an untreated control group.

Ratings of 1 to 4 (especially 1 to 3) indicate good to very good herbicidal activity. Rating grades from 6 to 9 (especially from 7 to 9) indicate a good tolerance (especially in crops).

In this experiment, the compounds of Table 1 show a strong herbicidal activity.

In Setaria and Stellaria, the following values ​​can be found at 4 kg / ha application rates:<tables id="tabl0007" num="0007"><img file="EP0264348A2_D0024.tif" /></tables>

Example B2: Post-emergent herbicide activity

(Contact herbicide)

A number of weeds, both monocot and dicot, were sprayed onto the plants after emergence (in the 4- to 6-leaf stage) with an aqueous active ingredient dispersion in a dosage of 4 kg of active ingredient per hectare, and these at 24 ° -26 ° C. and 45 -60% relative humidity kept. The test is evaluated 15 days after the treatment. In this experiment too, the compounds of Table 1 show good herbicidal activity.

Example B3 Herbicidal action for water rice

(Paddy)

The water weeds Echinochloa crus galli and Monocharia vag. are sown in plastic cups (60 cm² surface, 500 ml volume). After sowing, water is added to the surface of the earth. 3 days after sowing, the water level is raised to slightly above the earth's surface (3-5 mm). It is applied 3 days after sowing by spraying the test substances onto the containers. The dose used corresponds to an amount of active ingredient of 4 kg AS per hectare. The plant cups are then placed in the greenhouse under optimal growth conditions for the rice weeds, ie at 25 ° -30 ° C. and high air humidity.

The tests are evaluated 3 weeks after application. The compounds in Table 1 damage the weeds, but not the rice.

Example B4: Inhibition of growth in tropical ground cover legumes

(cover crops)

The test plants (centrosema plumieri and centrosema pubescens) are grown to the fully grown stage and cut back to a height of 60 cm. After 7 days, the active ingredient is injected as an aqueous emulsion. The test plants are kept at 70% relative atmospheric humidity and 6000 lux artificial light, 14 hours a day, at temperatures of 27 ° during the day and 21 ° C at night. The test is evaluated 4 weeks after the application. The new growth compared to the control is estimated and weighed and the phytotoxicity is assessed. In this experiment, the plants treated with the active ingredients in Table 1 at application rates of up to 3000 g / ha showed a significant reduction in new growth (less than 20% of new growth in untreated control plants) without the test plants being damaged in the process.

Example B5: Growth regulation on soybeans

"Hark" soybeans are sown in plastic containers with a 6: 3: 1 soil-peat-sand mixture and placed in a climatic chamber. Through optimal temperature selection, lighting, adding fertilizer and irrigation, the plants develop after about 5 weeks until the 5-6 trifolia leaf stage. At this point, the plants are sprayed with the aqueous broth of an active ingredient of the formula I until thoroughly wetted. The active ingredient concentration is up to 100 g ai / ha. The evaluation takes place about 5 weeks after application of the active ingredient. In comparison to untreated control plants, the active substances according to the invention in Table 1 increase the number and weight of the pods in the main shoot.

Example B6: Growth inhibition in cereals

Hordeum vulgare (summer barley) and secale (summer rye) are sown in plastic pots with sterilized soil in the greenhouse and watered as required. The sprouts are sprayed about 21 days after sowing with the aqueous spray mixture of an active ingredient in Table 1. The amount of active ingredient is up to 100 g active ingredient per hectare. The growth of the grain is assessed 21 days after application. Compared to untreated controls, the treated plants show a reduction in new growth and, in some cases, an increase in stem diameter.

Example B7: Growth inhibition in grasses

The grasses Lolium perenne, Poa pratensis, Festuca ovina, Dactylis glomerata and Cynodon dactylon are sown in plastic trays with soil-peat-sand mixture (6: 3: 1) in the greenhouse and watered as required. The accumulated grasses are cut back to a height of 4 cm weekly and sprayed with the aqueous spray mixture of an active ingredient from Tables 1 and 2 about 50 days after sowing and one day after the last cut. The amount of active ingredient is equivalent to up to 500 g of active ingredient per hectare. The growth of the grass is assessed 21 days after application.

The tested compounds in Table 1 bring about a reduction in new growth compared to the untreated control.

Formulation examples

Example F1: Formulation examples for active ingredients of the formula Iʹ

(% = Weight percent)

<tables id="tabl0008" num="0008"><img file="EP0264348A2_D0025.tif" /></tables>

Emulsions of any desired concentration can be prepared from such concentrates by dilution with water.<tables id="tabl0009" num="0009"><img file="EP0264348A2_D0026.tif" /></tables>

The solutions are suitable for use in the form of tiny drops.<tables id="tabl0010" num="0010"><img file="EP0264348A2_D0027.tif" /></tables>

An active ingredient solution is sprayed onto the carrier and the solvent is then evaporated off in vacuo.<tables id="tabl0011" num="0011"><img file="EP0264348A2_D0028.tif" /></tables>

Ready-to-use dusts are obtained by intimately mixing the carrier substances with the active ingredient.<tables id="tabl0012" num="0012"><img file="EP0264348A2_D0029.tif" /></tables>

The active ingredient is mixed well with the additives and ground well in a suitable mill. Spray powder is obtained which can be diluted with water to give a suspension of any desired concentration.<tables id="tabl0013" num="0013"><img file="EP0264348A2_D0030.tif" /></tables>

The active ingredient is mixed with the additives, ground and moistened with water. This mixture is extruded and then dried in an air stream.<tables id="tabl0014" num="0014"><img file="EP0264348A2_D0031.tif" /></tables>

The finely ground active ingredient is applied evenly in a mixer to the kaolin moistened with polyethylene glycol. In this way, dust-free coating granules are obtained.<tables id="tabl0015" num="0015"><img file="EP0264348A2_D0032.tif" /></tables>

The active ingredient is intimately mixed with the additives. This gives a suspension concentrate from which suspensions of any desired concentration can be prepared by dilution with water.