EP0775136A1

EP0775136A1 - 5-hydroxypyrazol-4-yl-carbonyl-substituted saccharin derivatives with herbicidal properties

Info

Publication number: EP0775136A1
Application number: EP95927734A
Authority: EP
Inventors: Peter Plath; Wolfgang Von Deyn; Stefan Engel; Uwe Kardorff; Hartmann König; Harald Rang; Matthias Gerber; Helmut Walter; Karl-Otto Westphalen
Original assignee: BASF SE
Current assignee: BASF SE
Priority date: 1994-08-08
Filing date: 1995-07-27
Publication date: 1997-05-28
Also published as: WO1996005197A1; JPH10506618A; US5723415A; HUT77177A; RU2159244C2; CA2197118A1; AU3166695A; CN1157616A; BR9508553A; DE4427997A1; HU216284B; ZA956577B

Abstract

The disclosure is of 5-hydroxypyrazol-4-yl-carbonyl-substituted saccharin derivatives of formula (I), in which the substituents have the following meanings: L,M stand for hydrogen, C1-C4 alkyl, C1-C4 alkoxy, C1-C4 alkylthio, chlorine, cyano, methylsulphonyl, nitro or trifluoromethyl; Z stands for hydrogen, C1-C4 alkyl, C3-C8 cycloalkyl, C3-C6-alkenyl, C3-C5-alkinyl, C1-C4 acyl, benzyl or phenyl (the phenyl rings optionally being each substituted by a halogen or C1-C4 alkyl); Q stands for a CO-J group; J stands for a 5-hydroxypyrazol ring linked at position 4 and of formula (II), in which R1 represents C¿1?-C4 alkyl, and R?2¿ represents hydrogen or methyl. Also disclosed are the salts of formula (I) compounds commonly used in agriculture.

Description

-HYDR0XYPYRAZ0L-4-YL-CARB0NYL-SUBSTITUTED SACCHARINE DERIVATIVES WITH HERBICIDAL EFFECT

Description 5

The present application relates to 5-hydroxypyrazol-4-ylcarbonyl-substituted saccharin derivatives of the formula I.

in which the substituents have the following meaning: 15

L, M is hydrogen, -CC ₄ alkyl, -C-C ₄ alkoxy, -C-C ₄ alkylthio, chlorine, cyano, methylsulfonyl, itro or trifluoromethyl;

Z is hydrogen, -CC ₄ -alkyl, C ₃ -C ₈ -cycloalkyl, C ₃ -C ₆ -alkenyl, 20 C ₃ -C ₅ -alkynyl, -C-C ₄ -acyl, optionally by halogen or Cχ-C _4th -Alkyl substituted benzyl or phenyl;

Q a residue CO-J,

25 J is a 5-hydroxypyrazole ring of the formula II linked in position 4

in which 35

R ¹ -C ₄ alkyl and

R2 is hydrogen or methyl,

as well as customary salts of the compounds I. 40

The invention further relates to herbicidal compositions comprising the compounds I and processes for controlling unwanted vegetation with the saccharin derivatives I.

45 saccharin derivatives with herbicidal activity cannot be found in the prior art. In contrast, unsubstituted saccharin (o-sulfobenzoimide, ie L, M, Q and Z in formula I = H) has been has long been known as a synthetic sweetener. 4-Hydroxy-saccharin (DE-OS 36 07 343) is also known as a sweetener. It is also known to use saccharin derivatives in pest control, for example JP publication 72/00419, 73/35457 (fungicides) and in pharmacy, for example EP-A-594 257 and patents mentioned therein. Heterocyclic compounds with a ring containing a sulfonamide group have become known as herbicides, and bentazone is a typical representative here

H

to call.

The object of the invention was to provide new herbicides with a basic structure hitherto unknown for this indication. Accordingly, the compounds I defined at the outset were found.

Compounds of the formula I are obtained by acylating 5-hydroxy-pyrazoles of the formula II with an acid chloride of the formula TV and rearranging the pyrazoles formed to give saccharin derivatives of the formula 1.1.

II IV

Catalyst,

in the formulas mentioned above, L, M and Z have the meaning given above. The first step of the reaction sequence, the acylation, is carried out in a generally known manner, e.g. B. by adding an acid chloride of formula IV to the solution or suspension of a 5-hydroxypyrazole II in the presence of an auxiliary base. The reactants and the auxiliary base are expediently used in approximately equimolar amounts. A slight excess of the auxiliary base, for example 1.2 to 1.5 molar equivalents, based on II, may be advantageous.

Suitable auxiliary bases are e.g. tertiary alkyl amines, pyridine or alkali carbonates, while methylene chloride, diethyl ether, toluene or ethyl acetate can be used as the solvent. During the addition of the acid chloride, the reaction mixture is advantageously cooled to 0-10 ° C, then at a higher temperature, e.g. stirred at a temperature of 25-50 ° C until the reaction is complete.

The processing takes place in the usual way, e.g. the reaction mixture is poured into water and extracted with methylene chloride. After drying the organic phase and removing the solvent, the crude 5-hydroxypyrazole ester can be used for rearrangement without further purification. Preparation examples for benzoic acid esters of 5-hydroxy-pyrazoles can be found, for. B. in EP-A-282 944 or US 4,643,757.

The rearrangement of the 5-hydroxypyrazole esters to the compounds of the formula 1.1 is advantageously carried out at from 20 ° C. to 40 ° C. in a solvent and in the presence of an auxiliary base and with the aid of a cyano compound as catalyst. As a solvent e.g. Acetonitrile, methylene chloride, 1,2-dichloroethane, ethyl acetate or toluene can be used. The preferred solvent is acetonitrile. Suitable auxiliary bases are tertiary alkylamines, pyridine or alkali carbonates, which are used in equimolar amounts or up to four times the excess. Preferred auxiliary base is tri-ethylamine in double

Quantity. Suitable catalysts are cyanide compounds such as potassium cyanide or acetone cyanohydrin, e.g. in an amount of 1 to 50, especially 5-20 mole percent, based on the 5-hydroxy-pyrazole ester. Acetone cyanohydrin is preferably used e.g. in amounts of 10 mole percent.

Examples of the rearrangement of benzoic acid esters of 5-hydroxypyrazoles can be found, for. B. in EP-A 282 944 or US 4,643,757, but only potassium carbonate or sodium carbonate in dioxane is used as a catalyst. The use of potassium cyanide or acetone cyanohydrin is indeed known in connection with the analogous rearrangement of enol esters of cyclohexane-1,3-diones (US Pat. No. 4,695,673), but no examples are known from the literature that cyanide compounds are particularly suitable for the Fries rearrangement of O-acyl derivatives of 5-hydroxypyrazole.

The processing takes place in the usual way, e.g. the reaction mixture is acidified with dilute mineral acids such as 5% hydrochloric acid or sulfuric acid and extracted e.g. with methylene chloride or ethyl acetate. For cleaning, the extract is extracted with cold 5 - 10% alkali carbonate solution, the end product passing into the aqueous phase. The product of the formula I is precipitated by acidifying the aqueous solution, or extracted again with methylene chloride, dried and then freed from the solvent.

The 5-hydroxypyrazoles of the formula II used as starting material are known and can be prepared by processes known per se (cf. EP-A 240 001 and J. Prakt. Chem. 3J L, 382 (1973)). 1,3-Dimethyl-5-hydroxypyrazole is a commercially available compound.

The starting materials of formula IV are known in a conventional manner by reacting saccharin carboxylic acid III

made with thionyl chloride.

Saccharin carboxylic acids III are known in some cases (4-COOH: zincke, Liebigs Ann. 427, 231 (1922), 5-COOH: Jacobsen, Chem. Ber. H, 1554 (1880), 6-COOH: Weber, Chem. Ber. 21, 1740 (1892)). DE-OS 36 07343 also describes the preparation of 4-chlorosaccharin-5-carboxylic acid.

Saccharin carboxylic acids can also be obtained by appropriate bro - or iodine - substituted saccharin derivatives of the formula AI

in which L, M and Z have the abovementioned meaning, or in the case of ZH compounds of the formula A2

in the presence of a palladium, nickel, cobalt or rhodium transition metal catalyst and a base with carbon monoxide and water or a C 1 -C 6 alcohol under increased pressure.

Iodosaccharins are already known from the literature: 6-iodosaccharin: De Roode, Amer. Chem. Journal H, 231 (1891). They are obtained either by permanganate oxidation of iodine-substituted 2-methylbenzenesulfonamides or by a Sandmeyer reaction from amino saccharins. Aminosaccharins are obtained by known methods by reduction of nitrosaccharins, which are either known (Kastle, Amer. Chem. Journal H, 184 (1889) or DRP 551423 (1930) or in a manner known from the literature from suitable nitrobenzene derivatives (Liebigs Ann 669.85 (1963) or nitrobenzenesulfonamides.

If, for example, L is methyl and M and Z are hydrogen, the reaction sequence can be represented as follows:

The catalysts nickel, cobalt, rhodium and in particular palladium can be metallic or in the form of conventional salts such as in the form of halogen compounds, for example P Cl ₂ , RhCl ₃ -H ₂ 0, acetates, for example Pd (OAc) ₂ cyanides etc. in the known valence levels available. Furthermore, metal complexes with tertiary phosphines, metal alkylcarbonyls, metal carbonyls, for example CO ₂ (CO) β, Ni (CO) ₄ , metal carbonyl complexes with tert. Phosphines, for example (PPh ₃ ) ₂ Ni (CO) ₂ or transition metal salts complexed with tertiary phosphines are present. The latter embodiment is particularly preferred in the case of palladium as a catalyst. The type of phosphine ligand is widely variable. For example, they can be represented by the following formulas: R ³ R3 \ ^ R5

P _ R _{4 or} _{R4 / P} _ _{(CH2) n} - P ^ _Rg

R ⁵

5 where n is the numbers 1, 2, 3 or 4 and the radicals R ³ to R ⁶ for low molecular weight alkyl, for example Ci-Cε-alkyl, aryl, C 1 -C ₄ -alkyl aryl, for example benzyl, or phenethyl, or Aryloxy stand. Aryl is, for example, naphthyl, anthryl and preferably optionally substituted phenyl, the substituents only having to be considered for their inertness to the carboxylation reaction, otherwise they can be varied widely and include all inert C-organic radicals such as Ci-C _ß -Alkyl radicals, for example methyl, carboxyl radicals such as COOH, COOM (M is, for example, an alkali metal, alkaline earth metal or ammonium salt), or C-organic radicals bound via oxygen, such as Ci-C _δ alkoxy radicals.

The phosphine complexes can be prepared in a manner known per se, for example as described in the documents mentioned at the outset. For example, one starts from customary commercially available metal salts such as PdCl ₂ or Pd (OCOCH ₃ ) ₂ and adds the phosphine ZB P (C ₆ H ₅ ) ₃ , P (nC ₄ Hg) ₃ , PCH ₃ (C ₆ H ₅ ) Add ₂ »1,2-bis (diphenylphosphino) ethane.

The amount of phosphine, based on the transition metal, is usually 0 to 20, in particular 0.1 to 10 mol equivalents, particularly preferably 1 to 5 mol equivalents.

The amount of transition metal is not critical. Of course, for reasons of cost, you will rather get a small amount, e.g. from 0.1 to 30 10 mol%, in particular 1 to 5 mol%, based on the starting material AI or A2.

To prepare saccharin carboxylic acids III, the reaction is carried out with carbon onoxide and at least equimolar amounts of water, based on the starting materials A1 and A2. The reaction partner water can also serve as a solvent, i.e. the maximum amount is not critical.

However, depending on the type of starting materials and the catalysts used, it may also be advantageous to use another inert solvent or the base used for the carboxylation as the solvent instead of the reaction partner.

Suitable inert solvents for carboxylation reactions are conventional solvents such as hydrocarbons, for example toluene, xylene, hexane, pentane, cyclohexane, ethers, for example methyl tert-butyl ether, tetrahydrofuran, dioxane, dimethoxyethane, substituted amides such as Dimethylformamide, per-substituted ureas such as tetra-C ₄ -alkylureas or nitriles such as benzonitrile or acetonitrile.

In a preferred embodiment of the process, one of the reactants, in particular the base, is used in excess, so that no additional solvent is required.

Bases suitable for the process are all inert bases which are able to bind the hydrogen iodide or hydrogen bromide released during the reaction. For example, tertiary amines such as triethylamine, cyclic amines such as N-methylpiperidine or N, N-dimethylpiperazine, pyridine, alkali metal or alkaline earth metal hydroxides, carbonates, or hydrogen carbonates or tetra-alkyl-substituted urea derivatives such as tetra-C 1 -C ₄ alkyl urea, for example tetramethyl urea.

The amount of base is not critical, usually 1 to 10, in particular 1 to 5, moles were used. When the base is simultaneously used as solvent, the amount is generally measured so that the reactants are dissolved, unnecessarily high excesses being avoided for reasons of practicality in order to save costs, to be able to use small reaction vessels and to give the reactants maximum contact guarantee.

During the reaction, the carbon monoxide pressure is adjusted so that there is always an excess of CO, based on AI or A2. The carbon monoxide pressure at room temperature is preferably 1 to 250 bar, in particular 5 to 150 bar CO.

The carbonylation is generally carried out continuously or batchwise at temperatures from 20 to 250 ° C., in particular at 30 to 150 ° C. In the case of discontinuous operation, carbon monoxide is expediently pressed continuously onto the reaction mixture in order to maintain a constant pressure.

From the resulting reaction mixture, the products can be prepared in the usual way, e.g. be isolated by distillation.

The starting materials AI or A2 required for the reaction are known or can be prepared in a manner known per se, for example as described in the prior art cited. In addition, they can be obtained analogously to the preparation instructions from Examples 1 to 12. With regard to the intended use, saccharin derivatives of the formula I are preferred in which the radicals L and M are hydrogen, methyl, methoxy, methylthio, chlorine, cyano, methylsulfonyl, nitro or trifluoromethyl. Furthermore, L and M are preferably hydrogen, -CC ₄ -alkyl and chlorine. Also preferred are compounds I with L and M = hydrogen or one of the radicals L or M = hydrogen and the other stands for methyl or chlorine.

The radical R ¹ in formula I preferably represents methyl and R ² preferably represents hydrogen or methyl.

The radical Z particularly preferably represents one of the organic radicals mentioned, in particular methyl, ethyl, propargyl, acetyl or phenyl.

Particularly preferred active ingredients can be found in Table 1. The groups mentioned for a substituent in Table 1 also represent a particularly preferred definition of the relevant substituent, independently of the special combination with other substituents in which they are mentioned.

The compounds I can be in the form of their agriculturally useful salts, the type of salt generally not being important. Usually the salts of such bases will be considered which do not adversely affect the herbicidal activity of I.

Particularly suitable basic salts are those of the alkali metals, preferably the sodium and potassium salts, those of the earth alkali metals, preferably calcium, magnesium and barium salts and those of the transition metals, preferably manganese, copper, zinc and iron salts and the ammonium salts which can carry one to three C 1 -C ₄ alkyl, hydroxy C 1 -C ₄ alkyl substituents and / or a phenyl or benzyl substituent, preferably diisopropylammonium, tetramethylammonium, tetrabutylammonium, trimethylbenzylammonium and trimethyl - (2-Hydroxyethyl) ammonium salts, the phosphonium salts, the sulfonium salts, preferably tri- (C ₁ -C ₄ -) alkylsulfonium salts, and the sulfoxonium salts, preferably tri- (Cι-C ₄ -) alkylsulfoxonium salts.

The compounds or the herbicidal compositions comprising them and their environmentally compatible salts of, for example, alkali metals, alkaline earth metals or ammonia and amines or the herbicidal compositions comprising them can be very weeds and harmful grasses in crops such as wheat, rice, corn, soybeans and cotton Good fight without significantly damaging the crops. This effect occurs especially at low application rates.

Taking into account the versatility of the application methods, the compounds or compositions containing them can also be used in a further number of crop plants for eliminating undesired plants, for example the following crops are suitable: Allium cepa, pineapple comosus, Arachis hypogaea, Asparagus officinalis , Beta vulgaris spp. altissima, Beta vulgaris spp. rapa, Brassica napus var. napus, Brassica napus var. napobrassica, Brassica rapa var. silvestris, Camellia sinensis, Carthamus tinctorius, Carya illinoinensis, Citrus limon, Citrus sinensis, Coffea arabica (Coffea canephora, Coffea libericaus), Cucumodison , Daucus carota, Elaeis guineensis, Fragaria vesca, Glycine max, Gossypium hirsutum, (Gossypium arboreum, Gossypium herbaceum, Gossypium vitifolium), Helianthus annuus, Hevea brasiliensis, Hordeum vulgare, Humulus lupulus, Ipomoealumisisumisum , Lycopersicon lycopersicum, Malus spp., Manihot esculenta, Medicago sativa, Musa spp., Nicotiana tabacum (N.rustica), Olea europaea, Oryza sativa, Phaseolus lunatus, Phaseolus vulgaris, Picea abies, Pinus spp., Pisum sativum, Prunus , Prunus persica, Pyrus communis, Ribes sylvestre, Ricinus communis, Saccharum officinarum, Seeale cereale, Solanum tuberosum, Sorghum bicolor (see vulgar), Theobroma cacao, Trifolium prate nse, Triticum aestivum, Triticum durum, Vicia faba, Vitis vinifera, Zea mays.

In addition, the compounds can also be used in crops which have been made largely resistant to the action of I or other herbicides by breeding and / or by means of genetic engineering methods.

The herbicidal compositions or the active compounds can be applied pre- or post-emergence. If the active substances are less compatible with 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 compounds grow more rapidly on the leaves underneath plant undesirable or reach the uncovered floor area (post-directed, lay-by).

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

The following are essentially considered as inert auxiliaries for the production of directly sprayable solutions, emulsions, pastes or old dispersions: mineral oil fractions from medium to high boiling points such as kerosene or diesel oil, furthermore coal tar oils and oils of vegetable or animal origin, aliphatic, cyclic and aromatic hydrocarbons , e.g. Paraffins, tetrahydronaphthalene, alkylated naphthalenes or their derivatives, alkylated benzenes and their derivatives, alcohols such as methanol, ethanol, propanol, butanol and cyclohexanol, ketones such as cyclohexanone or strongly polar solvents, e.g. Amines such as N-methylpyrrolidone, or water.

Aqueous use forms can be prepared from emulsion concentrates, suspensions, pastes, wettable powders or water-dispersible granules by adding water. For the production of emulsions, pastes or old 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, concentrates consisting of active substance, wetting agent, adhesive, dispersant or emulsifier and possibly solvent or oil can also be prepared which are suitable for dilution with water.

The surface-active substances are the alkali metal, alkaline earth metal 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 and of fatty alcohol glycol ether, condensation products of sulfonated naphthalene and its derivatives with formaldehyde, condensation products of naphthalene or naphthalene sulfonic acids with phenol and formaldehyde, polyoxyethylene octylphenol ether, ethoxylated isooctyl, octylphenylphenylphenylphenylphenylphenylphenylphenylphenylphenylphenylphenyl or phenylphenyl , Alkyl aryl polyether alcohols, isotridecyl alcohol, fatty alcohol ethylene oxide condensates, ethoxylated castor oil, polyoxyethylene alkyl ether or polyoxypropylene alkyl ether, lauryl alcohol polyglycol ether acetate, sorbitol ester, lignin sulfite waste liquor or methyl cellulose.

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

Granules, e.g. Coating, impregnation and homogeneous granules can be produced by binding the active ingredients to solid carriers.

10 places. Solid carriers are mineral soils such as silica, 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, urinary

15 substances and vegetable products such as flour, tree bark, wood and nutshell flour, cellulose powder or other solid carriers.

The formulations generally contain between 0.01 and 20 95% by weight, preferably between 0.5 and 90% by weight, of active ingredient. The active ingredients are used in a purity of 90% to 100%, preferably 95% to 100% (according to the NMR spectrum). The compounds Ia or Ia 'according to the invention can be formulated, for example, as follows: 25

I. 20 parts by weight of compound 1.08 are dissolved in a mixture consisting of 80 parts by weight of alkylated benzene, 10 parts by weight of the adduct of

8 to 10 moles of ethylene oxide in 1 mole of oleic acid-N-monoethanol-30 amide, 5 parts by weight of calcium salt of dodecylbenzenesulfonic acid and 5 parts by weight of the adduct of 40 moles of ethylene oxide with 1 mole of castor oil. By pouring the solution into 100,000 parts by weight of water and finely distributing it therein, an aqueous dispersion is obtained which contains 0.02% by weight of the active ingredient.

II. 20 parts by weight of compound 1.08 are dissolved in a mixture consisting of 40 parts by weight of cyclohexanone, 30 parts by weight of isobutanol, 20 parts by weight of

40 adduct of 7 moles of ethylene oxide with 1 mole

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 100,000 parts by weight of water and finely distributing it therein gives an aqueous solution

45 dispersion containing 0.02% by weight of the active ingredient. III. 20 parts by weight of the active ingredient 1.08 are in one

Dissolved mixture, which consists of 25 parts by weight of cyclohexanone, 65 parts by weight of a mineral oil fraction from the boiling point 210 to 280 ° C and 10 parts by weight of the adduct of 40 moles of ethylene oxide and 1 mole of castor oil. Pouring the solution into 100,000 parts by weight of water and finely distributing it therein gives an aqueous dispersion which comprises 0.02% by weight of the active ingredient.

IV. 20 parts by weight of active ingredient 1.08 are with

3 parts by weight of the sodium salt of diisobutyl-naphthalene-α-sulfonic acid, 17 parts by weight of the sodium salt of a lignin sulfonic acid from a sulfite waste liquor and 60 parts by weight of powdered silica gel are mixed well and ground in a hammer mill. A fine mixture of the mixture in 20,000 parts by weight of water contains a spray mixture which contains 0.1% by weight of the active ingredient.

V. 3 parts by weight of active ingredient 1.08 are with

97 parts by weight of finely divided kaolin mixed. In this way, a dust is obtained which contains 3% by weight of the active ingredient.

VI. 20 parts by weight of active ingredient 1.08 are 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-urea-formaldehyde condensate and 68 parts by weight of a paraffinic mineral oil. A stable oily dispersion is obtained.

In order to broaden the spectrum of activity and to achieve synergistic effects, the saccharin carboxylic acid derivatives can be mixed with numerous representatives of other herbicidal or growth-regulating active ingredient groups and applied together. For example, diazines, 4H-3,1-benzoxazine derivatives, benzothiadiazinones, 2,6-dinitroanilines, N-phenyl carbamates, thiol carbamates, halocarboxylic acids, triazines, amides, ureas, diphenyl ethers, triazinones, uracils, benzofuran derivatives, cyclohexan-l, come as mixing partners. 3-dione derivatives which carry, for example, a carboxy or carbimino group, quinoline carboxylic acid derivatives, imidazolinones, sulfonamides, sulfonylureas, aryloxy, heteroaryloxyphenoxypropionic acids and their salts, esters and amides and others. It may also be useful to apply the compounds I alone or in combination with other herbicides, mixed with other crop protection agents, for example with agents for controlling pests or phytopathogenic 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 added.

10 The application rates of active ingredient are 0.001 to 3.0, preferably 0.01 to 1.0 kg / ha of active substance (a.S.) depending on the control target, the season, the target plants and the growth stage.

Preparation Examples:

15

1. 2-methyl-6-acetaminobenzoic acid

90.6 g (0.6 mol) of 6-methylanthranilic acid are added to a solution of 24.8 g (0.62 mol) of NaOH in 500 ml of water, and 20 63.4 g (0.62 mol) of acetic anhydride are then added dropwise. After one hour of stirring with conc. HCl acidified to pH 3, the precipitate is filtered off, washed with water and at 50 ° C i. Vak. dried.

25 Yield: 107 g (0.55 mol) = 92% of theory , Mp: 189-190 ° C

2. 2-methyl-3-nitro-6-acetaminobenzoic acid

271 ml of 98% nitric acid are initially introduced at -5 ° C. and 30 portions of 106 g (0.55 mol) of the one prepared under 1. are added

2-methyl-6-acetaminobenzoic acid. After stirring for one hour at 10 ° C., the reaction mixture is poured into a mixture of 540 g of ice and 270 ml of water. The precipitate is filtered off, washed with water and at 50 ° C i. Vak. dried. 35 yield. 75.6 g (0.317 mol) = 58% of theory. Th., M.p .: 190-191 ° C.

After standing for a long time, the isomer nitrated in the 3-position separates from the filtrate. Yield: 21.3 g (0.089 mol) = 16% of theory. Th., Mp: 180-182 ° C 40

3. 2-methyl-3-nitro-6-aminobenzoic acid

450 ml of 2-N NaOH are introduced and 75.6 g (0.317 mol) of 2-methyl-3-nitro-6-acetaminobenzoic acid are added. The reaction mixture is then heated to 95 ° C. and left to stir at this temperature for one hour. After cooling to 10 ° C by adding 425 ml of 2N HCl acidified, sucks off the precipitate, washes with water and dries at 50 ° C i. Vac. ,

Yield: 50.7 g (0.258 mol) = 82% of theory. Th., M.p .: 183-184 ° C

5 4. Methyl 2-methyl-3-nitro-6-aminobenzoate

49.7 g (0.253 mol) of 2-methyl-3-nitro-6-aminobenzoic acid are dissolved in 380 ml of acetone and 43 g (0.51 mol) of sodium hydrogen carbonate 0 are added. The mixture is then heated to boiling until the CO ₂ evolution is complete. 35.3 g (0.28 mol) of dimethyl sulfate are then added dropwise to the suspension of the sodium salt of 2-methyl-3-nitro-6-aminobenzoic acid thus obtained at the boiling point of the acetone over the course of two hours, then refluxed eats three more hours and then lets cool. After pouring the reaction mixture into 1.8 l of water, the mixture is extracted with methylene chloride. After the organic phase has dried, the mixture is concentrated. The solid obtained is sufficiently pure for the subsequent reaction (NMR). 0

Yield: 50 g (0.238 mol) = 94% of theory. Th., Mp: 92-94 ° C

5. 2-methoxycarbonyl-3-methyl-4-nitro-benzenesulfonic acid chloride

5 58.5 g (0.278 mol) are dissolved with heating

2-methyl-3-nitro-6-amino-benzoic acid methyl ester in 280 ml of ice and pour this solution at 15-20 ° C in 85 ml of conc. HCl. A solution of 19.3 g (0.28 mol) of sodium nitrite in 60 ml of water is then added dropwise at 5-10 ° C. and stirring is continued at 5 ° C. for 30 minutes. Then this diazonium salt solution is added dropwise to a solution of 374 g of SO ₂ in 750 ml of glacial acetic acid, which contains 14 g of CuCl ₂ (dissolved in 30 ml of water). After the nitrogen evolution has ended, the mixture is stirred for a further 15 min and then poured into 1.4 l of ice water. The sulfonic acid chloride is separated off by extraction with 1.2 l of methylene chloride. After drying and concentrating the organic phase, 73 g (0.25 mol) (= 90% of theory) of an oil are obtained which, according to NMR (in CDCI ₃ ), is pure 2-methoxycarbonyl-3-methyl-4-nitro-ben- bolsulfonic acid chloride.

40 6. 4-methyl-5-nitrosaccharin

104 ml of 25% ammonia solution are introduced, 100 ml of water are added, and a solution of 48.7 g (0.166 mol) of 2-methoxycarbonyl-3-methyl-4-nitro-benzenesulfonic acid chloride in 45 70 ml of tetrahydrofuran is then added dropwise at 10 ° C. to. After stirring for three hours at 25 ° C., the mixture is concentrated on a rotary evaporator to remove water and THF. The remaining residue is stirred with ethyl acetate, sucks and washed with ethyl acetate. After drying i. Vac. he obtained 34 g (0.131 mol) = 79% of theory. Th. Of a white solid with mp: 312 ° C (dec.)

5 7. 2,4-Dimethyl-5-nitrosaccharin

This substance can be prepared by subsequent methylation of the saccharin obtained under 6 with dimethyl sulfate in the presence of NaOH. 0

8. 3-methyl-4-nitro-2- (N'-methyl) carboxamido-N-methylbenzenesulfonamide 50 ml of water are poured into 50 ml of 40% methylamine solution and a solution of 24.3 is added dropwise at 10 ° C g (83 mmol) 2-methoxy

15 carbonyl-3-methyl-4-nitro-benzenesulfonic acid chloride in 35 ml of THF. After stirring for one hour at 25 ° C., all volatile constituents are stripped off on a rotary evaporator, the residue is extracted with ethyl acetate, the organic phase is washed with water, dried and concentrated. The remaining residue crystallizes after standing for a long time.

Yield 10.3 g (40 mmol = 48% of theory), mp: 125-126 ° C, after recrystallization from ethyl acetate, mp: 144-145 ° C.

25 9. 4-methyl-5-amino-saccharin

33.6 g (0.13 mol) of 4-methyl-5-nitro-saccharin are dissolved in 1.2 l of water with heating to 45 ° C. and 5 g of Pd / C (10% on activated carbon) are added. Then it is passed under vigorous stirring

30 hydrogen gas on (pressureless hydrogenation). In the course of 4.5 hours 9 1 H _{2 are} absorbed. After cooling to 25 ° C., the catalyst is filtered off, concentrated to a volume of 200 ml and then acidified to pH 1. The precipitate is filtered off, washed with water and i at 50 ° C. Vac. dried. You get

35 23.4 g (0.11 mol = 85% of theory) of a white solid with mp: 272-273 ° C.

10. 4-methyl-5-iodo-saccharin

40 A mixture of 205 ml of glacial acetic acid, 160 ml of water and 40 ml of conc. HCl before and enters with stirring 23.4 g (0.11 mol) of 4-methyl-5-amino-saccharin at 15 - 20 ° C. 7.9 g (0.115 mol) of sodium nitrite are added dropwise to the resulting suspension at 5-10 ° C. and the mixture is left for 30 min. Stir at 5 ° C. The suspension

45 g of the diazonium salt is then added dropwise in portions to a solution of 19.1 g (0.115 mol) of potassium iodide in 170 ml of water heated to 50 ° C., nitrogen being formed. After cooling to room temperature The precipitated product is isolated by suction, washed with water and at 50 ° C. i. Vac. dried. 32.5 g (0.1 mol = 91% of theory) of a solid with mp: 257-258 ° C. are obtained. A combustion analysis showed an iodine content of 38.5% (theory 39.3%).

The product is sufficiently pure for subsequent implementation.

11. 4-methyl-saccharin-5-carboxylic acid

10

6.4 g (0.002 mol) of 4-methyl-5-iodo-saccharin are dissolved in 70 ml of tetramethyl urea and 30 ml of water 0.7 g, mixed with bis (triphenylphosphine) palladium chloride and the mixture in one 300 ml autoclave heated to 100 ° C and 36 h at a pressure of

15 100 bar carbon monoxide stirred.

For working up, the mixture is filtered and water and tetramethylurea are removed by distillation in a high vacuum. The residue is taken up in methyl tert-butyl ether (MTBE), with NaHCO ₃ solution. extracted and extracted again with MTBE after acidification with HCl. After concentration, 2.8 g of 4-methyl-saccharin-5-carboxylic acid (58% of theory) are obtained.

iH NMR (DMSO, 400.1 MHz): 2.85 (3H, s); 8.05 (1H, d); 8.2 (1H, d);

25

¹³ C NMR (DMSO, 100, 6 MHz): 167.4 (CO); 161.3 (CO); 141.6 (quart. C); 139.7 (quart. C); 138.7 (quart. C); 135.6 (CH); 125.4 (quart. C); 118.5 (CH); 15.4 (CH ₃ ).

30 12. 2,4-dimethyl-saccharin-5-carboxylic acid

7.3 g (0.02 mol) of 3-methyl-4-iodo-2- (N'-methyl) carboxamido-N-methyl-benzenesulfonamide together with 0.69 g of bis (triphenylphosphine) palladium chloride, 30 ml of water and 70 ml of tetra-35-methylurea are placed in a 300 ml autoclave, the mixture is heated to 100 ° C. and stirred for 36 hours at a pressure of 100 bar carbon monoxide.

After working up as described in Example 12, 4.1 g 40 of the title compound are obtained (0.014 mol = 72% of theory).

^! H NMR (DMSO, 400.1 MHz): 2.9 (3H, s); 3.15 (3H, s); 8.2 (2H, 2d); 14.0 (1H, s)

45 ¹³ C NMR (DMSO, 100.6 MHz): 167.3 (CO); 158.6 (CO); 139.7 (quart. C); 139.1 (quart. C); 138.9 (quart. C); 135.5 (CH); 124.6 (quart. C); 119.0 (CH); 22.9 (CH3); 15.6 (CH ₃ ).

13. 4-Amino-3-methyl-2- (N'-methyl) carboxarrtido-N-methylbenzenesulfonamide

Analogously to the procedure described in item 9, the 3-methyl-4-nitro-2- (N'-methyl) carboxamido-N-methyl-benzenesulfonate obtained in item 8 was hydrogenated without pressure.

The aniline derivative having the following structure was obtained in 93% yield, mp: 217-218 ° C.

SO ^M 2- ^H N ^C H ^H C ³ H3

14. 3-Methyl-4-iodo-2- (N'-methyl) carboxamido-N-methylbenzenesulfonamide

According to the procedure described in point 10, the above compound was diazotized and by reaction with KI to the iodobenzene derivative of the structure

S02-NHCH3 implemented.

Yield: 95%, mp: 60-62 ° C

15. 2,4-dimethyl-saccharin-5-carboxylic acid chloride

3.8 g (14.9 mmol) of 2,4-dimethyl-saccharin-5-carboxylic acid are suspended in 100 ml of toluene, heated to 80 ° C. and 3.5 g (29.8 mmol) of thionyl chloride are added dropwise. After two hours of refluxing, the mixture is decanted hot and the reaction mixture is concentrated on a rotary evaporator. The product obtained (3 g, 74% of theory) has an mp .: 149-150 ° C. 16. General procedure for the preparation of the compounds I

16.1Acylation of 5-hydroxy-1,3-dimethylpyrazole with a saccharine carboxylic acid chloride

1.01 g (11 mmol) of triethylamine are added to a suspension of 1.12 g (10 mmol) of 5-hydroxy-1,3-dimethylpyrazole in 70 ml of methylene chloride. A solution or suspension of 10 mmol of the acid chloride of the formula IV in 30 ml of methylene chloride is then added dropwise at 25 ° C. and the mixture is then heated to 45 ° C. for 5 hours. After cooling to 25 ° C., 60 ml of water are added to the reaction mixture, poured into a shaking funnel and the organic phase is separated off. After extraction of the aqueous phase with 50 ml of methylene chloride, the organic phases are combined and dried over sodium sulfate. After filtration and removal of the

Methylene chloride remains an oil that is used for rearrangement without further purification.

16.2 Rearrangement of the under 16.1. obtained pyrazole ester

The saccharin carboxylic acid O-acyl ester of 5-hydroxy-1,3-dimethylpyrazole (approx. 10 mmol) obtained in 16.1 is placed in 80 ml acetonitrile and only with 2.7 ml (2.2 g = 20 mmol) triethyl - Amine, then 0.2 g (2.3 mmol) of acetone cyanohydrin were added and the mixture was stirred at 25 ° C. for 16 hours. Then 30 g of 5% HCl are poured into the reaction mixture and extracted with methylene chloride. The organic phase is then extracted with 5% potassium carbonate solution, the organic phase is discarded and the alkaline aqueous phase is added by dropwise addition of conc. HCl acidified to pH 1, whereby the product precipitates as a viscous mass. For purification, the product is dissolved in methylene chloride, washed with water, dried over sodium sulfate and concentrated. The residue becomes crystalline by rubbing with diethyl ether / petroleum ether. The compounds listed in Table 1 can be obtained in an analogous manner:

Table 1 :

Rl

Examples of use

The herbicidal activity of the saccharin derivatives of the formula I was demonstrated by greenhouse experiments:

Plastic flower pots with loamy sand with about 3.0% humus as substrate served as culture vessels. The seeds of the test plants were sown separately according to species.

In pre-emergence treatment, the active ingredients suspended or emulsified in water were applied directly after sowing by means of finely distributing nozzles. The vessels were sprinkled lightly to promote germination and growth, and then covered with transparent plastic hoods until the plants had grown. This cover causes the test plants to germinate uniformly, provided this was not impaired by the active ingredients.

For the purpose of post-emergence treatment, the test plants, depending on the growth habit, were first grown to a height of 3 to 15 cm and only then treated with the active ingredients suspended or emulsified in water. The test plants were either sown directly and grown in the same containers or they are first grown separately as seedlings and transplanted into the test containers a few days before the treatment.

The plants were kept at temperatures of 10 - 25 ° C or 20 - 35 ° C depending on the species. The trial period lasted 2 to 4 weeks. During this time, the plants were cared for and their response to the individual treatments was evaluated.

Evaluation was carried out 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.

Claims

7. 5-hydroxypyrazol-4-yl-carbonyl-substituted saccharin derivatives of the formula I.

in which the substituents have the following meaning:

L, M is hydrogen, -CC ₄ alkyl, -C-C ₄ alkoxy, -C ~ C ₄ -alkylthio, chlorine, cyano, methylsulfonyl, itro or trifluoromethyl;

Z is hydrogen, -CC ₄ -alkyl, C ₃ -C ₈ -cycloalkyl, Cs-C _δ- alkenyl, C ₃ -C ₅ -alkynyl, -C-C ₄ -acyl, benzyl or phenyl, the phenyl rings each optionally by Halogen or -CC ₄ alkyl are substituted;

Q a residue CO-J,

J is a 5-hydroxypyrazole ring of the formula II linked in position 4

R ^l

in which

Rl -CC ₄ alkyl and

R ^{2 is} hydrogen or methyl,

as well as agriculturally customary salts of the compounds I.

8. saccharin derivatives of the formula I according to claim 1, in which the

L and M are hydrogen, -CC ₄ alkyl or chlorine; 9. saccharin derivatives of formula I according to claims 1 and 2, in which the radicals L and M are hydrogen, methyl, methoxy, methylthio, chlorine, cyano, methylsulfonyl, nitro or trifluoromethyl.

5

10. Herbicidal composition containing at least one saccharin derivative of the formula I according to claim 1 and customary inert additives.

11. A method of combating undesirable plant growth, characterized in that a herbicidally effective amount of a saccharin derivative of the formula I according to claim 1 is allowed to act on the plants or their habitat.

15 12. A process for the preparation of the compounds of formula I according to claim 1, characterized in that 5-hydroxypyrazoles of the formula II

R ^l

25 in which

R ¹ -C ₄ alkyl and

R ^{2 is} hydrogen or methyl,

30 with an acid chloride of the formula IV

where L, M and Z have the meaning given in claim 1, acylated and rearranged the acylation product in the presence of a catalyst to give the compounds I.

40

45