Isoxazol(isothiazols)-5-carboxamides.

0001The present invention relates to substituted isoxazole and isothiazole-5-carboxamides and their use for combating undesirable plant growth.

0002Isoxazole and isothiazole carboxylic acids or their derivatives are known. These are the 5-aminocarbonyl-3-methyl-4-isoxazolecarboxylic acid, the 5-aminocarbonyl-3-methyl-4-isoxazolecarboxylic acid ethyl ester, the 4,5-isothiazole dicarboxamide and the 5-carbamoyl-4-isothiazolecarboxylic acid (J. Chem Soc. Perkin Trans. I, 1982, 2391; J. Heterocyclic. Chem. 22, 1561 (1985); J. Chem. Soc. 1959, 3961). Possible uses of these substances are not described.

0003It has been found that isoxazole (isothiazole) -5-carboxamides of the formula la<chemistry id="chem0001" num="0001"><img file="EP0337263A2_D0001.tif" /></chemistry>in the<ul id="ul0001" list-style="none"><li>X oxygen or sulfur,</li><li>_R¹ Hydrogen, optionally by C₁-C₃-Alkoxy, C₁-C₃-Halogenalkoxy, halogen, cyano or phenyl, which by halogen, C₁-C₄-Alkyl, C₁-C₄Haloalkyl, C₁-C₄-Alkoxy, C₁-C₄-Haloalkoxy, C₁-C₄-Alkylthio, C₁-C₄-Halogenalkylthio, cyano or nitro may be substituted, substituted C₁-C₁₀-Alkyl,</li><li>C.₁-C₄Alkoxy, optionally by C₁-C₄-Alkyl or halogen substituted C₃-C₈-Cycloalkyl, a 5- to 6-membered heterocyclic radical with one or two heteroatoms, selected from the group consisting of oxygen, sulfur and nitrogen, which by C₁-C₄-Alkyl, carboxyl or C₁-C₄Alkoxycarbonyl can be substituted,</li><li>or optionally by C₁-C₆-Alkyl, C₁-C₆Haloalkyl, C₁-C₆-Alkoxy, C₁-C₆-Haloalkoxy, C₁-C₆-Alkylthio, C₁-C₆Haloalkylthio, halogen, nitro or cyano substituted phenyl,</li><li>R² Formyl, 4,5-dihydro-oxazol-2-yl or a radical of the formula COYR⁵ or CONR⁶ R⁷, in which</li><li>Y for oxygen or sulfur,</li><li>_R⁵ for hydrogen, C₁-C₈-Alkyl, which by C₁-C₄-Alkoxy, C₁-C₄-Alkoxy-C₁-C₄-alkoxy, halogen, cyano, hydroxy, trimethylsilyl, C₁-C₄-Alkylthio, C₁-C₄Alkylamino, C₁-C₄Dialkylamino, C₁-C₄Alkylsulfinyl, C₁-C₄Alkylsulfonyl, carboxyl, C₁-C₄-Alkoxycarbonyl, C₁-C₄Dialkylaminocarbonyl, C₁-C₄-Dialkoxyphosphonyl, alkaniminoxy, benzyloxy, optionally by C₁-C₄-Alkyl, C₁-C₃-Alkoxy or halogen-substituted benzoyl or optionally by C₁-C₄-Alkyl, C₁-C₄-Alkoxy, C₁-C₄Haloalkyl, halogen, nitro or cyano substituted phenyl, which can be substituted by thienyl, furyl, tetrahydrofuryl, phthalimido or pyridyl,</li><li>optionally by phenyl, which by C₁-C₄-Alkyl, C₁-C₄-Alkoxy, C₁-C₄-Halogenalkyl, halogen, nitro or cyano may be substituted, substituted C₃-C₈Alkenyl,</li><li>C.₃-C₆-Halogenalkenyl, optionally by hydroxy or C₁-C₄-Alkoxy substituted C₃-C₈-Alkynyl,</li><li>C.₃-C₆Cycloalkyl,</li><li>Cs-Cs cycloalkenyl,</li><li>optionally by C₁-C₄-Alkyl, C₁-C₄-Alkoxy, C₁-C₄Haloalkyl, halogen, nitro, cyano, C₁-C₄Alkoxycarbonyl or acylamino substituted phenyl,</li><li>a 5- to 6-membered heterocyclic radical with one or two heteroatoms selected from the group consisting of oxygen, sulfur and nitrogen or a benzotriazole radical,</li><li>C.₆-C₇-Cycloalkanimino, phthalimido, succinimido, for the residues<chemistry id="chem0002" num="0002"><img file="EP0337263A2_D0002.tif" /></chemistry> -CH₂-CH (OH) -CH₂(OH),</li><li>for one equivalent of a cation from the group of the alkali metals, alkaline earth metals, manganese, copper, iron, ammonium and substituted ammonium or for the rest<chemistry id="chem0003" num="0003"><img file="EP0337263A2_D0003.tif" /></chemistry>where R⁸ and R⁹ independently of each other C₁-C₄-Alkyl, C₂-C₆Alkoxyalkyl, C₃-C₆-Cycloalkyl, phenyl, furyl or together a methylene chain of the formula - (CH₂)_m- with m = 4 to 7 chain links and R⁹ additionally means hydrogen,</li><li>R⁶ for hydrogen, C₁-C₈-Alkyl or C₃-C₈Cycloalkyl and</li><li>R⁷ for hydrogen or C₁-C₈-Alkyl stand or where</li><li>R⁶ and R⁷ form a methylene chain with 4 or 5 links,</li><li>_R³ Hydrogen, optionally by hydroxy, halogen, C₁-C₄-Alkoxy, C₁-C₄-Alkylthio or C₁-C₄Dialkylamino substituted C₁-C₈-Alkyl</li><li>or optionally by C₁-C₄-Alkyl, halogen or C₁-C₄-Halogenalkyl substituted C₃-C₈Cycloalkyl and</li><li>R⁴ Hydrogen, hydroxyl, C₁-C₄-Alkoxy,</li><li>optionally by C₁-C₄-Alkoxy, C₁-C₄-Haloalkoxy, C₁-C₄-Alkylthio, C₁-C₄-Dialkylamino, halogen, C₃-C₆-Cycloalkyl or phenyl, which is replaced by halogen, cyano, nitro, C₁-C₄-Alkyl, C₁-C₄Haloalkyl, C₁-C₄-Alkoxy, C₁-C₄-Haloalkoxy, C₁-C₄-Alkylthio or C₁-C₄-Halogenalkylthio may be substituted, substituted C₁-C₁₀-Alkyl,</li><li>optionally by halogen or C₁-C₄-Alkoxy substituted C₃-C₁₀Alkenyl or C₃-C, o-alkynyl,</li><li>optionally by C₁-C₆-Alkyl, C₁-C₆Haloalkyl, C₁-C₆-Alkoxy, C₁-C₆-Haloalkoxy, Ci-C₆-Alkylthio, C₁-C₆-Halogenalkylthio, halogen, nitro or cyano substituted C₃-C₈Cycloalkyl, C₁-C₄Dialkylamino, one optionally by Ci-C₆-Alkyl, C₁-C₆Haloalkyl or halogen-substituted 3- to 6-membered heterocyclic radical having one or two heteroatoms, selected from the group consisting of oxygen, sulfur and nitrogen, naphthyl optionally substituted by methyl,</li><li>or optionally by Ci-C₆-Alkyl, C₁-C₆Haloalkyl, C₁-C₆-Alkoxy, C₁-C₆-Haloalkoxy, C₁-C₆-Alkylthio, C₁-C₆-Halogenalkylthio, halogen, nitro, cyano, formyl, C₁-C₆-Alkanoyl or C.₁-C₆-Halogenalkanoyl substituted phenyl or</li><li>R³ and R⁴ together a rest of the structure - (CH₂)_n- Y_p- (CH₂)_q-, where n and q are 1, 2 or 3, p 0 or 1 and Y is oxygen, sulfur or N-methyl, or the rest of the formula - (CH₂)₃-CO- form,</li><li>as well as their environmentally compatible salts, are herbicidally active.</li></ul>

0004The methyl, alkoxy, alkenyl and alkynyl radicals for R¹, R³, R⁴, R^S, R⁶ and R⁷ can be unbranched or branched and preferably contain 1 to 4 carbon atoms. The same applies to the alkyl radicals, which are substituents in the radicals R¹, R³, R⁴, R⁵, R⁶ and R⁷ may be included, as well as for the alkyl groups in the haloalkyl, alkoxy, haloalkoxy, alkylthio, haloalkylthio, dialkylamino, alkanoyl, haloalkanoyl and alkoxycarbonyl radicals.

0005Halogen substituents are preferably chlorine substituents.

0006The heterocyclic residues for R¹ are saturated or unsaturated. For example, tetrahydropyranyl, tetrahydrofuryl, pyrazolyl, thienyl, furyl, pyridyl and tetrahydrofuryl are suitable. These residues can be identified by C₁-C₄-Alkyl-, carboxyl- or C₁-C₄-Alkylcarbonyl groups to be substituted.

0007The heterocyclic residues for R⁵ can optionally be saturated or unsaturated. Suitable residues are thienyl, furyl, tetrahydrofuryl, triazolyl, imidazolyl, tetrahydropyranyl, pyridyl, morpholino and piperidino.

0008Saturated or unsaturated heterocyclic radicals for R⁴ are for example tetrahydropyranyl, tetrahydrofuryl, thiazolyl, pyridyl, morpholino, piperidino, pyrimidyl.

0009The compounds I according to the invention can, for example, form addition salts with inorganic and organic acids or with alkyl halides or, if one of the substituents has acidic properties, they can be reacted with inorganic and organic bases to give salts. The corresponding salts also belong to the invention.

0010Isoxazole (isothiazole) -5-carboxamides preferred as herbicidal active ingredients are those of the formula Ia in which R³ Means hydrogen.

0011Compounds of the formula Ia are furthermore preferred as active compounds in which X is oxygen or sulfur, R¹ Hydrogen or C₁-C₄-Alkyl, R² COYR^S, R³ Hydrogen, R⁴ C.₁-C₄-Alkyl or C₃-Cs cycloalkyl mean. For these compounds, R means⁵ preferably hydrogen, C₁-C₄Alkyl, optionally by C₁-C₄-Alkyl, C₁-C₄-Halogenalkyl, C, -C₄-Alkoxy, C₁-C₄Alkylthio or halogen substituted phenyl or the rest<chemistry id="chem0004" num="0004"><img file="EP0337263A2_D0004.tif" /></chemistry>where again R⁸ and R⁹ preferably for C₁-C₄-Alkyl stand.

0012Isoxazole (isothiazole) -5-carboxamides of the formula<chemistry id="chem0005" num="0005"><img file="EP0337263A2_D0005.tif" /></chemistry>in the X, R ', R², R³ and R⁴ have the meanings given for formula la, with the proviso that X is sulfur when R 'CH₃, R² COOH or COOC₂H₅ and R³ and R⁴ Is hydrogen and that X is oxygen when R¹ Hydrogen, R² COOH or CONH₂ and R³ and R⁴ Mean hydrogen are new.

0013The isoxazole (isothiazole) -5-carboxamides of the formula I or Ia can be prepared in the following ways:

00141. A process for the preparation of compounds of the formula Ib and la, in which R² COOR^S and R⁵ Hydrogen or C₁-C₈-Alkyl mean (see Scheme 1), is based on the reaction of an isoxazole or isothiazole-4,5-dicarboxylic acid dialkyl ester II (R⁸ = C₁-C₈-Alkyl) with aqueous base and subsequent reaction with mineral acid to a carboxylic acid III. Lower alkyl esters (R^s = R⁸ = C₁-C₄Alkyl) into consideration, with dimethyl ester and diethyl ester being particularly preferred.

0015The reaction is carried out in such a way that a dicarboxylic acid dialkyl ester II at temperatures between about 0 and 80 ° C., preferably between 0 and 50 ° C., in an organic solvent, for example methanol or ethanol, with a strong base, for example NaOH, KOH or Ca ( OH)₂, treated. In general, about 1 equivalent of the strong base is used in aqueous solution. After the reaction has taken place, the mixture is cooled and acidified with a strong mineral acid, for example hydrochloric acid or sulfuric acid. The resulting carboxylic acid III can be isolated in the usual way, for example by suction or by extraction with an organic solvent.

0016To convert the carboxylic acid III into the carboxylic acid halide IV, the acid III is reacted in a conventional manner with an inorganic acid halide, such as thionyl chloride, phosphorus tri- or phosphorus pentahalides, with the chlorides being preferred. The inorganic acid halide is expediently used in 1 to 5 molar equivalents, preferably 1 to 2 molar equivalents. You can work without a solvent or in the presence of an inert organic solvent such as benzene or toluene at temperatures between room temperature and the boiling point of the inorganic acid halide or the inert organic solvent. In some cases, the addition of a catalyst such as dimethylformamide or 4-dimethylaminopyridine can be advantageous. After the reaction has ended, the acid halide IV can be isolated in the customary manner, for example by distilling off the excess of inorganic acid halide and the organic solvent and subsequent distillation of the acid chloride IV at normal pressure or reduced pressure.

0017The carboxamides Ib are obtained from the carboxylic acid halides by reaction with an amine V. It is expedient to proceed in such a way that the carboxylic acid halide in an inert organic solvent such as dichloroethane, or an ether such as diethyl ether or methyl tert-butyl ether with an amine V. , also dissolved in an organic solvent. The amine V is expediently used in a 2- to 5-fold molar amount, preferably in a 2 to 3-fold molar amount, in order to bind the hydrogen halide formed. One can also work in the presence of an auxiliary base such as a tertiary amine, for example triethylamine. In this case, 1 to 1.5 molar equivalents of amine V are sufficient. The reaction temperature can be between 0 and 50 ° C., preferably between 0 and 20 ° C. The reaction is generally complete after 1 to 12 hours. The mixture can be worked up in the customary manner, for example by hydrolysis with water and extraction of the product of the formula Ib with an organic solvent and concentration of the organic solvent. For purification, the product of the formula Ib can, for example, be recrystallized or chromatographed.

0018The free carboxylic acids Ic can be obtained from the 4-alkoxycarbonyl-isoxazole-5-carboxamides or 4-alkoxycarbonyl-isothiazole-5-carboxamides Ib by reaction with aqueous bases and subsequent reaction with mineral acids. The reaction is carried out in such a way that the ester Ib at temperatures between 0 and 80 ° C., preferably between 0 and 50 ° C., in an organic solvent such as methanol or ethanol with a base such as NaOH, KOH or Ca (OH)₂ treated. In general, about 1 to 3 equivalents, preferably 1 to 1.5 equivalents, of the strong base are used in aqueous solution. After the reaction, the mixture is acidified with cooling using a strong mineral acid, for example hydrochloric acid or sulfuric acid. The resulting carboxylic acids Ic can be isolated by suction or by extraction with an organic solvent and concentration of this organic solvent. For further purification of the acids Ic, these can be recrystallized or chromatographed.<chemistry id="chem0006" num="0006"><img file="EP0337263A2_D0006.tif" /></chemistry>

0019The isoxazole and isothiazole-4,5-dicarboxylic acid dialkyl esters II required as starting material for this process are known from the literature (J. Org. Chem. 43, 3736 (1978); Chem. Pharm. Bull. 28, 3296 (1980); Tetrahedron 30, 1365 (1974)) or can be prepared by methods known from the literature.

00202nd Another process for the preparation of the compounds Id is based on the reaction of an isoxazole or isothiazole-5-carboxylic acid halide VI with an amine V. The chlorides are preferred as carboxylic acid halides VI. The procedure is expediently such that the carboxylic acid halide is reacted with an amine V, likewise dissolved in an organic solvent, in an inert organic solvent such as dichloromethane or an ether such as diethyl ether or methyl tert-butyl ether. The amine V is expediently used in 2 to 5 times the molar amount, preferably 2 to 3 times the molar amount, in order to bind the hydrogen halide formed. You can also work in the presence of an auxiliary base such as a tertiary amine (triethylamine). In this case, 1 to 1.5 molar equivalents of amine V are sufficient. The reaction temperature can be between 0 and 50 ° C., preferably between 0 and 20 ° C. The reaction is generally complete after 1 to 12 hours. The mixture can be worked up in the customary manner, for example by hydrolysis with water and extraction of the product VII with an organic solvent and concentration of the organic solvent.

0021The 5-aminocarbonyl-isoxazole-4-carboxylic acids or 5-aminocarbonyl-isothiazole-4-carboxylic acids of the formula Id are obtained from the isoxazole or isothiazolamides VII by reaction with alkyl lithium, preferably with addition of a solvent which is inert under the reaction conditions, such as diethyl ether or tetrahydrofuran. As a rule, you work in a nitrogen atmosphere at temperatures between -70 and -80 ° C. The alkyl lithium compound is generally used in this process in a 2 -3 times molar amount based on the amide of formula VII used. After the reaction is complete, the mixture is treated with carbon dioxide, preferably in an inert solvent such as diethyl ether or, for example, tetrahydrofuran, the desired products of the formula Id in which R² Carboxyl means receives.

0022Isoxazole and isothiazolamides of the formula Id in which R² stands for formyl, are obtained if dimethylformamide is used instead of the carbon dioxide. After the usual work-up, substituted 4-formyl-isoxazole-5-carbonamides or 4-formyl-isothiazole-5-carbonamides of the formula Id are obtained.<chemistry id="chem0007" num="0007"><img file="EP0337263A2_D0007.tif" /></chemistry>

0023The isoxazole and isothiazole-5-carboxylic acid halides VI required as starting material for this process are known from the literature or can be prepared from the corresponding carboxylic acids VIII in a conventional manner, as already described above.<chemistry id="chem0008" num="0008"><img file="EP0337263A2_D0008.tif" /></chemistry>

0024The carboxylic acids VIII required for this are also known from the literature (Chemical Reports 106, 3345 (1973), J. Chem. Soc. 1959, 3061, J. Chem. Soc. 1963, 2032; Adv. In Heterocyclic Chem. 14, 1 (1972) ) or can be prepared by methods generally known in the literature, for example from the corresponding alcohols or aldehydes by oxidation or the corresponding nitriles by hydrolysis.<ul id="ul0002" list-style="none"><li>3rd Another method leads to compounds le in which R² COOR⁵ and R⁵ optionally by C₁-C₄-Alkoxy, C₁-C₄-Alkoxy-C₁-C₄-alkoxy, halogen, C₁-C₄-Alkylthio, C₁-C₄Alkylsulfinyl, C₁-C₄Alkylsulfonyl, C₁-C₄Alkoxycarbonyl, Benzyloxy, or by Phenyl, which by C₁-C₄-Alkyl, C₁-C₄-Alkoxy, C₁-C₄-Halogenalkyl, halogen, nitro or cyano may be substituted, substituted C₁-C₈-Alkyl, C₃-C₆-Cycloalkyl, optionally by phenyl, which is by C₁-C₄-Alkyl, C₁-C₄-Alkoxy, C₁-C₄-Halogenalkyl, halogen, nitro or cyano may be substituted, substituted C₃-C₈Alkenyl, C₃-C₈Alkynyl, C₆-C₇-Cycloalkanimino, succinimido or a radical of the formula<chemistry id="chem0009" num="0009"><img file="EP0337263A2_D0009.tif" /></chemistry>mean, by reacting an acid Ic with a corresponding alcohol IX in the presence of a strong mineral acid such as hydrochloric acid or sulfuric acid at a temperature between 0 and 100 ° C., preferably between 20 and 50 ° C. In general, the alcohol IX is used in excess , but an inert solvent can also be used.<chemistry id="chem0010" num="0010"><img file="EP0337263A2_D0010.tif" /></chemistry></li><li>4th Another process for the preparation of the compounds of the formula le consists in reacting an acid Ic with an alcohol or thiol IX in the presence of a dehydrating agent (for example dicyclohexylcarbodiimide (DCC)) at a temperature between -20 and 50 C, preferably between 0 and 30 ° C. As a rule, the starting materials are reacted in an approximately stoichiometric amount. The reaction is preferably carried out in the presence of an inert solvent, for example Tetrahydrofuran, dichloromethane or toluene.<chemistry id="chem0011" num="0011"><img file="EP0337263A2_D0011.tif" /></chemistry></li><li>5. Another process for the preparation of the compounds Ic is based on the reaction of an alkyl carboxylic acid If with an alkali metal alkoxide X, such as sodium or potassium alkoxide, with a corresponding alcohol IX in a manner known per se at temperatures between 20 ° C. and the boiling point of the alcohol chosen IX.<chemistry id="chem0012" num="0012"><img file="EP0337263A2_D0012.tif" /></chemistry></li><li>6. Compounds of the formula Ig in which R² for COOR⁵ stands, where R⁵ a salt-forming cation such as, for example, alkali metal, alkaline earth metal, ammonium or substituted ammonium, are obtained by reacting a substituted isoxazole or isothiazole-4-carboxylic acid Ic with one equivalent of the salt-forming cation. If it is an inorganic cation such as sodium, potassium or calcium, dissolves or Expediently, the acid Ic is suspended in water or a lower alcohol or a mixture thereof and one equivalent of the salt-forming cation is added. The salt-forming cation can be used, for example, in the form of its hydroxide, carbonate or bicarbonate, preferably in the form of its hydroxide. The reaction is generally complete after a few minutes and can be worked up as usual, for example by precipitation and suction or by concentrating the solution. For the preparation of compounds Ig, in which B^e represents ammonium or organic ammonium, the acid Ic is dissolved or suspended in an organic solvent, such as diethyl ether, tetrahydrofuran or dioxane, and the mixture is treated with an equivalent of ammonia, an amine or a tetraalkylammonium hydroxide.</li></ul>

0025Among the amines that can be used, the following should be mentioned: Methylamine, ethylamine, n-propylamine, isopropylamine, n-butylamine, isobutylamine, sec.-butylamine, n-amylamine, isoamylamine, hexylamine, heptylamine, octylamine, nonylamine, decylamine, undecylamine, dodecylamine, tridecylamine, tetradecylamine, hexadecaminamine, pentadecaminamine, pentadecaminamine , Octadecylamine, methylethylamine, methylisopropylamine, methylhexylamine, methylnonylamine, methylpentadecylamine, methyloctadecylamine, ethylbutylamine, ethylheptylamine, ethyloctylamine, hexylheptylamine, hexyloctylamine, Dimethylamine, diethylamine, di-n-propylamine, diisopropylamine, di-n-amylamine, diisoamylamine, dihexylamine, diheptylamine, dioctylamine, trimethylamine, triethylamine, tri-n-propylamine, triisopropylamine, tri-n-butylamine, triisobutylamine, trisec. -butylamine, tri-n-amylamine, ethanolamine, n-propanolamine, isopropanolamine, diethanolamine, N, N-diethylamine, N-ethylpropanolamine, N-butylethanolamine, allylamine, n-butenyl-2-amine, n-pentenyl- 2-amine, 2,3-dimethylbutenyl-2-amine, di-butenyl-2-amine, n-hexenyl-2-amine, propylenediamine, tallow amine, cyclopentylamine, cyclohexylamine, dicyclohexylamine, piperidine, morpholine and pyrrolidine.

0026In the case of the tetraalkylammonium hydroxides, for example, tetramethyl, tetraethyl or trimethylbenzylammonium hydroxide can be used. As a rule, the ammonium salt or organic ammonium salt precipitates out of the solution and can be isolated by customary methods. Alternatively, the salt of formula Ig can also be obtained by concentrating the solvent.<chemistry id="chem0013" num="0013"><img file="EP0337263A2_D0013.tif" /></chemistry><ul id="ul0003" list-style="none"><li>7. Another method leads to connections Ih in which R² CONR⁶R⁷ means. It consists in the reaction of an ester Ib with a primary or secondary amine XI. The process is carried out in such a way that an ester Ib is reacted with a 1- to 50-fold molar amount of amine XI, optionally in an organic solvent, at temperatures between room temperature and the boiling point of the amine or the organic solvent. Lower alkyl esters, especially the methyl and ethyl esters, are preferred as the ester Ib. The reaction products Ih can be isolated in a customary manner, for example by suctioning off or concentrating the solution, and, if appropriate, be further purified by recrystallization or chromatography.<chemistry id="chem0014" num="0014"><img file="EP0337263A2_D0014.tif" /></chemistry></li><li>8th. Another method for the synthesis of the compounds Ib consists in the reaction of an isoxazole or isothiazole-4,5-dicarboxylic acid dialkyl ester II with an amine V.</li></ul>

0027Lower alkyl esters, in particular dimethyl esters or diethyl esters, are particularly suitable as dialkyl esters II. The reaction is carried out in such a way that a dicarboxylic acid dialkyl ester II at temperatures between 0 and 100 ° C, preferably between 50 and 80 ° C in an organic solvent such as an alcohol such as methanol or ethanol with approximately one equivalent of a primary or secondary amine V treated. After the reaction has taken place, the mixture is cooled and suction filtered or concentrated. The product of formula Ib obtained can be further purified using customary standard methods, such as recrystallization or chromatography.<chemistry id="chem0015" num="0015"><img file="EP0337263A2_D0015.tif" /></chemistry><ul id="ul0004" list-style="none"><li>9. Compounds of the formula li can be obtained by reacting a substituted isothiazole-4,5-dicarboxylic anhydride XII with an amine V. The reaction is expediently carried out in such a way that the anhydride XII is initially introduced in an inert solvent, such as an ether or halogenated hydrocarbon, and about molar amounts of an amine V, optionally also dissolved in an inert solvent, are added dropwise. After the reaction has ended, the reaction product is suctioned off or isolated by concentrating the solvent used. In some cases, the isomeric amides XIII can be formed in this process, with the amides li generally being the preferred.<chemistry id="chem0016" num="0016"><img file="EP0337263A2_D0016.tif" /></chemistry></li></ul>

0028The isothiazole-4,5-dicarboxylic acid anhydrides XII required as starting material for this process are known from the literature (J. Chem. Soc. 1959, 3061) or can be synthesized by methods known from the literature.<ul id="ul0005" list-style="none"><li>10th Another process for the preparation of compounds of the formula Ik consists in reacting an acid Ic with an alcohol or thiol XIV in the presence of 1-methyl-2-halogenopyridinium iodides at a temperature between 20 and 80 ° C., preferably between 30 and 40 ° C. The reaction is carried out in the presence of an inert solvent, for example dichloromethane or toluene. The method is known in principle from the literature (Chem. Lett., 1045 (1975); ibid., 13 (1976); ibid., 49/1976)).<chemistry id="chem0017" num="0017"><img file="EP0337263A2_D0017.tif" /></chemistry></li></ul>

0029The following examples illustrate the preparation of the precursors for the synthesis of compounds 1 and la:

Example a

003011.7 g of aniline are added dropwise to 10.0 g of 3-ethyl-isoxazole-5-carboxylic acid chloride in 150 ml of dichloromethane while cooling with ice. The mixture is stirred overnight at room temperature, water and conc. Hydrochloric acid and separates the organic phase. After washing the organic phase with sodium bicarbonate solution and concentration, 11.8 g of 3-ethyl-isoxazole-5-carboxylic acid anilide are obtained as colorless crystals of mp 122-124 ° C.

0031The isoxazole-5-carboxamides VII can be synthesized in an analogous manner:<chemistry id="chem0018" num="0018"><img file="EP0337263A2_D0018.tif" /></chemistry><tables id="tabl0001" num="0001"><img file="EP0337263A2_D0019.tif" /></tables><tables id="tabl0002" num="0002"><img file="EP0337263A2_D0020.tif" /></tables><tables id="tabl0003" num="0003"><img file="EP0337263A2_D0021.tif" /></tables><tables id="tabl0004" num="0004"><img file="EP0337263A2_D0022.tif" /></tables><chemistry id="chem0019" num="0019"><img file="EP0337263A2_D0023.tif" /></chemistry><tables id="tabl0005" num="0005"><img file="EP0337263A2_D0024.tif" /></tables>

Example b

003265 g of diethyl 3-methyl-isoxazole-4,5-dicarboxylate dissolved in 100 ml of ethanol are added dropwise to 18.9 g of potassium hydroxide in 100 ml of water at room temperature. After 16 hours is poured onto 300 ml of water, extracted with ether and the aqueous phase with conc. Acidified hydrochloric acid. The mixture is extracted with dichloromethane and, after concentration, 3-methyl-4-ethoxycarbonyl-isoxazole-5-carboxylic acid is obtained as colorless crystals with a melting point of 54-58 ° C.

Example c

0033A solution of 14.9 g NaOH in 120 ml water and 150 ml methanol is added dropwise to 85.5 g dimethyl 3-ethyl-isothiazole-4,5-dicarboxylate in 300 ml methanol. After 2 hours, the mixture is concentrated, 1.5 l of water are added to the residue, the mixture is stirred and extracted with ether. The aqueous phase is acidified with conc. Hydrochloric acid and shake out with dichloromethane. Concentration of the organic phases gives 76.4 g of 3-ethyl-4-methoxycarbonyl-isothiazole-5-carboxylic acid, mp. 43-45 C.

0034Analogously to examples b and c, the isoxazole (isothiazole) -5-carboxylic acids III can be synthesized, for example:<chemistry id="chem0020" num="0020"><img file="EP0337263A2_D0025.tif" /></chemistry><tables id="tabl0006" num="0006"><img file="EP0337263A2_D0026.tif" /></tables><tables id="tabl0007" num="0007"><img file="EP0337263A2_D0027.tif" /></tables>

Preparation examples for compounds I and la

example 1

00352.9 g of isopropylamine are added dropwise to 10 g of 3-methyl-isoxazole-4,5-dicarboxylic acid diethyl ester dissolved in 100 ml of methanol and the mixture is then heated to reflux. After 7 hours, the mixture is concentrated and the remaining oil is chromatographed on silica gel (toluene: acetone = 9: 1). 5-Iso-propylaminocarbonyl-3-methyl-4-isoxazole-carboxylic acid methyl ester is obtained as colorless crystals of mp. 64-66 ° C (compound no. 1005)

Example 2

00362.6 g of ester from Example 1 and 0.8 g of potassium hydroxide are stirred in 20 ml of water and 20 ml of ethanol for 16 hours at room temperature. Then it is diluted with water, with conc. Acidified hydrochloric acid and shaken with dichloromethane. After concentration, 1.8 g of 5-iso-propylaminocarbonyl-3-methyl-4-isoxazolecarboxylic acid, colorless crystals of mp 86-92 * C (compound no. 1004)

Example 3

003770 ml of n-butyllithium (1.6 molar in n-hexane) are added dropwise to 9.0 g of anilide from example a, dissolved in 200 ml of absolute tetrahydrofuran. The mixture is stirred for half an hour and poured onto 500 g of solid carbon dioxide. After standing overnight, the mixture is concentrated and the residue between H₂0, sodium hydroxide solution and ethyl acetate distributed. By concentrating the ethyl acetate phase, 2.0 g of starting material can be recovered. By acidifying the aqueous phase with conc. Hydrochloric acid and suction are obtained 8.30 g of 5-anilinocarbonyl-3-ethyl-4-isoxazolecarboxylic acid, colorless crystals of mp. 150-152 ° C (compound no. 1015)

Example 4

00385.0 g of 5-tert-butylaminocarbonyl-3-methyl-4-isoxazolecarboxylic acid are dissolved in 200 ml of methanol and 5 ml of conc. H₂SO₄ admitted. After 2 days, the mixture is concentrated, the residue is partitioned between ethyl acetate and water and the organic phase is concentrated. 4.0 g of 5-tert-butylaminocarbonyl-3-methyl-4-isoxazolecarboxylic acid methyl ester are obtained as a colorless oil (compound no. 1007). H-NMR (CDCl₃): δ = 1.48 (s; 9H), 2.50 (s; 3H), 3.99 (s; 1 H), 9.42 (bs; 1 H, NH).

Example 5

a) 3-Ethyl-4-methoxycarbonyl-isothiazole-5-carboxylic acid chloride

003973 g of carboxylic acid from Example c and 80 g of thionyl chloride are heated to reflux in 200 ml of toluene in the presence of a little dimethylformamide until the evolution of gas has ended. The crude carboxylic acid chloride remaining after the concentration in quantitative yield is directly reacted further.

b) 5-iso-propylaminocarbonyl-3-ethyl-isothiazole-4-carboxylic acid methyl ester

00408.4 g of isopropylamine are slowly added dropwise to 16.5 g of crude acid chloride from a) in 200 ml of dichloromethane with ice cooling. The mixture is stirred overnight, hydrolyzed with 150 ml of water and the organic phase is separated off. After washing the organic phase with bicarbonate solution, dilute hydrochloric acid and water, the mixture is concentrated. 16.2 g of 5-iso-propylaminocarbonyl-3-ethyl-isothiazole-4-carboxylic acid methyl ester of mp 55-56 ° C. (compound no. 3007) are obtained.

Example 6

00412.8 g of KOH in 30 ml of water are added to 11 g of the ester from Example 5 in 50 ml of ethanol and the mixture is stirred overnight at room temperature. It is diluted with 150 ml of water, extracted with ether and the aqueous phase is acidified with conc. Hydrochloric acid. Shaking out with dichloromethane and concentration gives 10 g of 5-iso-propylaminocarbonyl-3-ethyl-isothiazole-4-carboxylic acid, mp. 138-140 C (compound no. 3006).

Example 7

00424.0 g of 5-tert-butylaminocarbonyl-3-methyl-4-isoxazolecarboxylic acid methyl ester and 50 ml of conc. Ammonia is heated to reflux for 3 hours. After cooling, the mixture is diluted with water, extracted with dichloromethane and concentrated. 5-tert-Butylaminocarbonyl-3-methyl-4-isoxazole-carbonamide is obtained as colorless crystals of mp. 155-158 ° C (compound No. 1).

Example 8

004356 ml of butyllithium (1.6 molar in n-hexane) are added dropwise to 8 g of 3-methyl-isoxazole-5-carboxylic acid tert-butylamide in 150 ml of tetrahydrofuran at -78 ° C. The mixture is stirred for 1 hour and then 22 ml of dimethylformamide are slowly added dropwise. The mixture is allowed to come to room temperature overnight, hydrolyzed with water, neutralized with concentrated hydrochloric acid and extracted with ether. The oil remaining after concentration is chromatographed on silica gel using cyclohexane / ethyl acetate. The first fraction obtained is 4-formyl-3-methylisoxazole-5-carboxylic acid tert-butylamide, pale yellow crystals of mp 36-38 C (compound no. 2).

Example 9

a) 3-methyl-4-ethoxycarbonyl-isoxazole-5-carboxylic acid chloride

004413.3 g of carboxylic acid from Example b and 20 ml of thionyl chloride are heated to reflux in the presence of a little dimethylformamide until the evolution of gas has ended. The crude carboxylic acid chloride remaining after the concentration in quantitative yield is directly reacted further.

0045b) 3.4 g of diethylamine are slowly added dropwise to 5 g of crude acid chloride from a) in 100 g of dichloromethane with ice cooling. The mixture is stirred overnight, hydrolyzed with water and the organic phase is separated off. After washing the organic phase with bicarbonate, the mixture is concentrated. 5.0 g of 5-diethylaminocarbonyl-3-methyl-isoxazole-4-carboxylic acid ethyl ester are obtained as a brown oil (compound no. 3). H-NMR (CDCl₃): 5 = 1.15 (t; 3H), 1.27 and 1.31 (2t; 6H), 2.50 (s; 3H), 3.17 (q; 2H), 3.58 (q; 2H), 4.28 (q; 2H).

Example 10

00465.0 g of ester from Example 9 and 1.4 g of potassium hydroxide are stirred in 10 ml of water and 20 ml of ethanol at room temperature. When the reaction has ended, the mixture is diluted with water and extracted with dichloromethane. The aqueous phase is then acidified with hydrochloric acid, extracted with dichloromethane and concentrated. 3.0 g of 5-diethylaminocarbonyl-3-methyl-isoxazole-4-carboxylic acid are obtained as a light oil (compound no. 4). H-NMR (CDCl₃): 6 = 1.28 and 1.32 (2t; 6H), 2.60 (s; 3H), 3.59 and 3.62 (2q; 4H), 10.50 (bs; 1H, COOH).

Example 11

0047A mixture of 1.2 g of 2-methyl-propan-2-thiol, 3.0 g of 5-tert is added dropwise to a stirred suspension of 4.1 g of 1-methyl-2-chloropyridinium iodide in 40 ml of dichloromethane at room temperature .-Butylaminocarbonyl-3-methyl-isoxazole-4-carboxylic acid and 5.9 g tri-n-butylamine in 20 ml dichloromethane. The mixture is heated under reflux for 3 h, the solvent is removed in vacuo and the crude product is purified by column chromatography on silica gel. 2.1 g of 5-tert-butylaminocarbonyl-3-methyl-isoxazole-4-carboxylic acid tert-butylthioester are obtained as a yellow oil (compound no. 2003).

0048Analogously to Examples 1 to 10, the compounds listed in Tables 1 to 3 below can be prepared, for example.<tables id="tabl0008" num="0008"><img file="EP0337263A2_D0028.tif" /></tables><tables id="tabl0009" num="0009"><img file="EP0337263A2_D0029.tif" /></tables><tables id="tabl0010" num="0010"><img file="EP0337263A2_D0030.tif" /></tables><tables id="tabl0011" num="0011"><img file="EP0337263A2_D0031.tif" /></tables><tables id="tabl0012" num="0012"><img file="EP0337263A2_D0032.tif" /></tables><tables id="tabl0013" num="0013"><img file="EP0337263A2_D0033.tif" /></tables><tables id="tabl0014" num="0014"><img file="EP0337263A2_D0034.tif" /></tables><tables id="tabl0015" num="0015"><img file="EP0337263A2_D0035.tif" /></tables><tables id="tabl0016" num="0016"><img file="EP0337263A2_D0036.tif" /></tables><tables id="tabl0017" num="0017"><img file="EP0337263A2_D0037.tif" /></tables><tables id="tabl0018" num="0018"><img file="EP0337263A2_D0038.tif" /></tables><tables id="tabl0019" num="0019"><img file="EP0337263A2_D0039.tif" /></tables><tables id="tabl0020" num="0020"><img file="EP0337263A2_D0040.tif" /></tables><tables id="tabl0021" num="0021"><img file="EP0337263A2_D0041.tif" /></tables><tables id="tabl0022" num="0022"><img file="EP0337263A2_D0042.tif" /></tables><tables id="tabl0023" num="0023"><img file="EP0337263A2_D0043.tif" /></tables><tables id="tabl0024" num="0024"><img file="EP0337263A2_D0044.tif" /></tables><tables id="tabl0025" num="0025"><img file="EP0337263A2_D0045.tif" /></tables><tables id="tabl0026" num="0026"><img file="EP0337263A2_D0046.tif" /></tables>

0049Analogously, further connections with the general structure can also be produced, for example<chemistry id="chem0021" num="0021"><img file="EP0337263A2_D0047.tif" /></chemistry>where X and Y are oxygen or sulfur, and for example<ul id="ul0006" list-style="none"><li>R 'for a radical from the group Q1 to Q61,</li><li>R⁵ for a remainder from group M1 to M78,</li><li>R³ for a rest from group P₁-P₁₁</li><li>R⁴ stand for a remainder from the group L1 to L195 and</li><li>the residues X, Y, P, Q, M and L can be combined as desired.</li><li>R¹, R⁵, R³ and R⁴ can mean, for example, the following radicals:<img file="EP0337263A2_D0048.tif" /><img file="EP0337263A2_D0049.tif" /><img file="EP0337263A2_D0050.tif" /><img file="EP0337263A2_D0051.tif" /><img file="EP0337263A2_D0052.tif" /><img file="EP0337263A2_D0053.tif" /><img file="EP0337263A2_D0054.tif" /><img file="EP0337263A2_D0055.tif" /><img file="EP0337263A2_D0056.tif" /><img file="EP0337263A2_D0057.tif" /></li></ul>

0050The compounds Ia or the herbicidal compositions comprising them can be sprayed, atomized, for example in the form of directly sprayable solutions, powders, suspensions, also high-strength aqueous, oily or other suspensions or dispersions, emulsions, oil dispersions, pastes, dusts, sprays or granules. Dusting, scattering or pouring can be used. The application forms depend entirely on the purposes; in any case, they should ensure the finest possible distribution of the active compounds according to the invention.

0051The compounds la are generally suitable for the preparation of directly sprayable solutions, emulsions, pastes or oil dispersions from mineral oil fractions of medium to high boiling point, such as kerosene or diesel oil, furthermore from coal tar oils and from oils of vegetable or animal origin, from aliphatic, cyclic and aromatic hydrocarbons, e.g. Toluene, xylene, paraffin, tetrahydronaphthalene, alkylated naphthalenes or their derivatives, methanol, ethanol, propanol, butanol, cyclohexanol, cyclohexanone, chlorobenzene, isophorone, or strongly polar solvents, such as N, N-dimethylformamide, dimethyl sulfoxide, N-methylpyrrolidone or water.

0052Aqueous use forms can be prepared from emulsion concentrates, dispersions, pastes, wettable powders or water-dispersible granules by adding water. To prepare emulsions, pastes or oil dispersions, the substrates as such or dissolved in an oil or solvent can be homogenized in water by means of wetting agents, adhesives, dispersants or emulsifiers. However, it is also possible to prepare concentrates composed of an active substance, wetting agents, adhesives, dispersants or emulsifiers and possibly solvents or oil, which are suitable for dilution with water.

0053The surface-active substances are the alkali, alkaline earth and ammonium salts of aromatic sulfonic acids, for example lignin, phenol, naphthalene and dibutylnaphthalenesulfonic acid, and of fatty acids, alkyl and alkylarylsulfonates, alkyl, lauryl ether and fatty alcohol sulfates, and salts of sulfated hexa- , Hepta- and octadecanols, as well as fatty alcohol glycol ether, condensation products of sulfonated naphthalene and its derivatives with formaldehyde, condensation products of naphthalene or the naphthalenesulfonic acids with phenol and formaldehyde, polyoxyethylene octylphenol ether, ethoxylated isooctyl, octyl or nonylphenol, alkylphenol, tributylphenyl polyglycol ether, alkylaryl polyether alcohols, isotridecyl alcohol, fatty alcohol ethylene oxide condensates, ethoxylated castor oil, polyoxyethylene ethoxylated ethoxylated oil, polyoxyethylene ethoxylated alcohol, polyoxyethylene ethoxylated alcohol, polyoxyethylene ethoxylated ethoxylated oil, polyoxyethylene ethoxylated alcohol, polyoxyethylene ethoxylated alcohol

0054Powders, materials for broadcasting and dusts can be prepared by mixing or grinding the active substances together with a solid carrier.

0055Granules, for example coated granules, impregnated granules and homogeneous granules, can be prepared by binding the active ingredients to solid carriers. Solid carriers are mineral earths such as silica gel, silicas, silica gels, silicates, talc, kaolin, limestone, lime, chalk, bolus, loess, clay, dolomite, diatomaceous earth, calcium and magnesium sulfate, magnesium oxide, ground plastics, fertilizers such as ammonium sulfate, ammonium phosphate, Ammonium nitrate, ureas and vegetable products such as corn flour, tree bark, wood and nutshell flour, cellulose powder or other solid carriers.

0056Examples of such preparations are:<ul id="ul0007" list-style="none"><li>I. 90 parts by weight of compound no. 1006 are mixed with 10 parts by weight of N-methyl-α-pyrrolidone and a solution is obtained which is suitable for use in the form of tiny drops.</li><li>11. 20 parts by weight of compound no. 1006 are dissolved in a mixture consisting of 80 parts by weight of xylene, 10 parts by weight of the adduct of. 8 to 10 moles of ethylene oxide in 1 mole of oleic acid-N-monoethanolamide, 5 parts by weight of calcium salt of dodecylbenzenesulfonic acid and 5 parts by weight of the adduct and 40 moles of ethylene oxide in 1 mole of castor oil. By pouring and finely distributing the solution in water, one obtains. an aqueous one. Dispersion.</li><li>111. 20 parts by weight of compound no. 1022 are dissolved in a mixture consisting of 40 parts by weight of cyclohexanone, 30 parts by weight of isobutanol, 20 parts by weight of the adduct of 7 moles of ethylene oxide and 1 mole of isooctylphenol and 10 parts by weight of the adduct of 40 moles of ethylene oxide with 1 mole of castor oil. Pouring the solution into water and finely distributing it therein gives an aqueous dispersion which contains 0.02% by weight of the active ingredient.</li><li>IV. 20 parts by weight of compound no. 1049 are dissolved in a mixture consisting of 25 parts by weight of cyclohexanol, 65 parts by weight of a mineral oil fraction with a boiling point of 210 to 280 ° C. and 10 parts by weight of the adduct of There is 40 moles of ethylene oxide with 1 mole of castor oil. Pouring the solution into water and finely distributing it therein gives an aqueous dispersion which contains 0.02% by weight of the active ingredient.</li><li>V. 20 parts by weight of the active ingredient No. 3038 are mixed well with 3 parts by weight of the sodium salt of diisobutylnaphthalene-a-sulfonic acid, 17 parts by weight of the sodium salt of a lignin sulfonic acid from a sulfite liquor and 60 parts by weight of powdered silica gel and ground in a hammer mill. By finely distributing the mixture in 20,000 parts by weight of water, a spray liquor is obtained which contains 0.1% by weight of the active ingredient.</li><li>VI. 3 parts by weight of compound no. 1075 are intimately mixed with 97 parts by weight of finely divided kaolin. In this way, a dusting agent is obtained which contains 3% by weight of the active ingredient.</li><li>VII. 30 parts by weight. of active ingredient no. 1220 are intimately mixed with a mixture of 92 parts by weight of powdered silica gel and 8 parts by weight of paraffin oil which has been sprayed onto the surface of this silica gel. In this way, a preparation of the active ingredient with good adhesiveness is obtained.</li><li>VIII. 20 parts by weight of active ingredient no. 1026 are mixed with 2 parts by weight of calcium salt of dodecylbenzenesulfonic acid, 8 parts by weight of fatty alcohol polyglycol ether, 2 parts by weight of sodium salt of a phenol-formaldehyde condensate and 68 parts by weight of a paraffinic Mineral oil mixed intimately. A stable oily dispersion is obtained.</li></ul>

0057The formulations contain between 0.1 and 95% by weight, preferably between 0.5 and 90% by weight, of active ingredient.

0058The herbicidal compositions or the active compounds can be applied pre- or preferably post-emergence. If the active ingredients are less compatible for certain crop plants, application techniques can be used in which the herbicidal compositions are sprayed with the aid of sprayers in such a way that the leaves of the sensitive crop plants are not struck wherever possible, while the active ingredients are applied to the leaves of undesirable plants growing below them or the uncovered floor area (post-directed, lay-by).

0059Depending on the control target, the season, the target plants and the stage of growth, the application rates of active ingredient are 0.001 to 5, preferably 0.01 to 1 kg / ha.

0060In view of the detectable spectrum of action for combating the undesirable plants, the tolerance for crop plants or the desired influencing of their growth, and in view of the variety of application methods, the compounds of the formula Ia and the herbicidal compositions comprising them can be used in a large number of crop plants.

0061For example, the following crops can be considered:<tables id="tabl0027" num="0027"><img file="EP0337263A2_D0058.tif" /></tables><tables id="tabl0028" num="0028"><img file="EP0337263A2_D0059.tif" /></tables><tables id="tabl0029" num="0029"><img file="EP0337263A2_D0060.tif" /></tables>

0062To broaden the spectrum of activity and to achieve synergistic effects, the isoxazole- (isothiazole) -5-carboxamides of the formula Ia can be mixed with numerous representatives of other herbicidal or growth-regulating active compound groups and applied together. For example, diazines, 4H-3,1-benzoazine derivatives, benzothiadiazinones, 2,6-dinitroanilines, N-phenyl carbamates, thiol carbamates, halocarboxylic acids, triazines, amides, ureas, diphenyl ethers, triazinones, uracils, benzofuran derivatives, cyclohexane-1,3- dione derivatives, quinoline carboxylic acids, sulfonylureas, imidazolinones, (hetero) aryloxyphenoxypropionic acids, their salts, esters and amides and other active substances.

0063It may also be useful to bring the compounds of the formula Ia alone or in combination with other herbicides, together with other crop protection agents, for example with agents for controlling pests or phytopatogenic fungi or bacteria. Also of interest is the miscibility with mineral salt solutions, which are used to remedy nutritional and trace element deficiencies. Non-phytotoxic oils and oil concentrates can also be produced.

Examples of use

0064The effect of the) soxazoi (isothiazoi) -5-carboxamides of the formula Ia on plant growth can be shown by greenhouse experiments:<ul id="ul0008" list-style="none"><li>Plastic flower pots with 300 cm serve as culture vessels³ Content and loamy sand with about 3% humus as a substrate. The seeds of the test plants are sown flat according to species.</li></ul>

0065In pre-emergence treatment, the processed active ingredients are applied to the surface of the earth immediately afterwards. For this purpose, they are suspended or emulsified in water as a distribution medium and sprayed by means of finely distributing nozzles. After the application of the agents, the vessels are lightly sprinkled to start germination and growth. Then cover the containers with transparent plastic covers until the plants open. This cover causes the test plants to germinate evenly, unless this is affected by the active ingredients.

0066For the purpose of post-emergence treatment, plants are either sown directly or grown in the same containers, or the plants are first grown separately as seedlings and transplanted into the test containers a few days before the treatment.

0067Depending on the growth habit, the test plants are then treated at a height of 3 to 15 cm with the active ingredients suspended or emulsified in water as a distribution agent and sprayed through finely distributing nozzles. The application rate for post-emergence treatment is 1.0 and 3.0 kg / ha as

0068The test vessels are then set up in the greenhouse, warmer areas (20 to 35 ° C.) being preferred for heat-loving species and 10 to 20 ° C. being preferred for such temperate climates. The trial period spans 2 to 4 weeks. During this time, the plants are cared for and their response to the individual treatments is evaluated.

0069Evaluation is based on a scale from 0 to 100. 100 means no emergence of the plants or complete destruction of at least the aerial parts and 0 means no damage or normal growth.

0070The plants used in the greenhouse experiments consist of the following types:<tables id="tabl0030" num="0030"><img file="EP0337263A2_D0061.tif" /></tables>

0071Active ingredient No. 1006, selected by way of example, combats undesirable plants very well in the pre-emergence process at an application rate of 3.0 kg / ha.

0072When used post-emergence, the active ingredients nos. 1004, 1014, 3018, 1026, 1006, 1049 and 1022 show, for example, at 1 to 3 kg_/ha application rate herbicidal activity against a broad spectrum of undesirable plants. In addition, the compounds No. 1075 and 3038 show a very good herbicidal action on broad-leaved plants with simultaneous selectivity in maize. In addition to excellent herbicidal activity, compound no. 1211 shows selectivity in wheat.