WO1993016079A1

WO1993016079A1 - Triazolopyrimidinesulfonamides as herbicides

Info

Publication number: WO1993016079A1
Application number: PCT/EP1993/000171
Authority: WO
Inventors: Hans Tobler
Original assignee: Ciba-Geigy Ag
Priority date: 1992-02-07
Filing date: 1993-01-26
Publication date: 1993-08-19
Also published as: EP0630377A1; IL104627A0; ZA93795B; MX9300599A; AU3451593A; CA2105278A1

Abstract

Triazolo[1,5-a]pyrimidine-2-sulfonamides of formula (I), in which R1 and R2 independently of one another are hydrogen, halogen, C1-C4alkyl, C1-C4haloalkyl, C1-C4alkoxy, C1-C4haloalkoxy, C1-C4alkoxy-C1-C4-alkyl, nitro, phenyl or S(O)nR3; R3 is C1-C4alkyl, C1-C4haloalkyl, C2-C4alkenyl, C2-C4alkynyl, benzyl or optionally substituted phenyl; n is the number 0, 1 or 2; R4, R5, R6, R7 and R8 independently of one another are hydrogen or C1-C4alkyl; and X and Y independently of one another are hydrogen, C1-C4alkyl or C3-C6cycloalkyl; and the agrochemically acceptable salts of these compounds, with the proviso that the radicals X and Y are not simultaneously hydrogen, have herbicidal properties pre- and post-emergence and are readily degradable. Described are the preparation of these compounds and their use as herbicidal active ingredients.

Description

Tr1azolopyr1mid1nesulfonam1des as herbicides

The present invention relates to novel herbicidally active and plant-growth-inhibiting triazolo[l,5-a]pyrimidine-2-sulfonamides, to processes for their preparation, compositions containing these triazolopyrimidinesulfonamides as active ingredients, and to their use for controlling weeds, especially selectively in crops of useful plants, and for inhibiting the growth of plants.

l,2,4-Triazolo[l,5-a]pyrimidine-2-sulfonamides which have a herbicidal activity are known. Such compounds are described, for example, in US Patent 4 818 273.

Novel herbicidally active triazolo[l,5-a]pyrimidine-2-sulfonamides have now been which are distinguished from the l-2,4-triazolo[l,5-a]pyrimidine-2-sulfonamides which have already been disclosed by the fact that they are more readily degradable.

The triazolo[l,5-a]pyrimidine-2-sulfonamides according to the invention are those of the formula I

in which

C₁-C₄haloalkyl, C_rC₄alkoxy, C_rC₄haloalkoxy, C₁-C₄alkoxy-C₁-C₄-alkyl, nitro, phenyl or S(0)_nR₃; R₃ is C_rC₄alkyl, C_rC₄haloalkyl, C₂-C₄alkenyl, C₂-C₄alkynyl, benzyl or optionally substituted phenyl; n is the number 0, 1 or 2; R₄, R₅, R₆, R and R₈ independently of one another are hydrogen or C_rC₄alkyl; and X and Y independently of one another are hydrogen, ^alkyl or C₃~C₆cycloalkyl; and the agrochemically acceptable salts of these compounds, with the proviso that the radicals X and Y are not simultaneously hydrogen.

Halogen in the above definitions is to be understood as meaning fluorine, chlorine, bromine or iodine, preferably fluorine, chlorine and bromine.

Suitable alkyl groups for Rj to Rg, X and Y can be straight-chain or branched alkyl groups, for example methyl, ethyl, n-propyl, iso-propyl, n-butyl, sec-butyl, iso-butyl or tert-butyl; preferably alkyl groups having 1 to 2 carbon atoms.

Haloalkyl groups which are suitable for R_l5 R₂ and R₃ are alkyl groups which are mono- or polysubstituted by halogen, halogen specifically being fluorine, chlorine, bromine or iodine. Preferred from amongst these alkyl groups which are mono- or polysubstituted by halogen are alkyl groups which are mono- to trisubstituted by halogen, in particular fluorine or chlorine, for example fluoromethyl, difluoromethyl, trifluoromethyl, chloromethyl, dichloromethyl, trichloromethyl, 2,2,2-trifluoroethyl, 2-fluoroethyl, 2-chloroethyl and 2,2,2-trichloroethyl; preferably difluoromethyl and trifluoromethyl.

Alkoxy radicals which are suitable for R-- and R₂ are, for example, methoxy, ethoxy, propyloxy, iso-propyloxy, n-butyloxy, iso-butyloxy, sec-butyloxy and tert-butyloxy; preferably methoxy and ethoxy.

Haloalkoxy radicals which are suitable for Rj and R₂ are, for example, difluoromethoxy, trifluoromethoxy, 2,2,2-trifluoroethoxy, 1,1,2,2-tetrafluoroethoxy, 2-fluoroethoxy, 2-chloroethoxy or 2,2-difluoroethoxy; preferably difluoromethoxy and trifluoromethoxy.

Alkoxyalkyl radicals which are suitable for R| and R₂ are, for example, methoxymethyl, methoxyethyl, ethoxy ethyl, ethoxyethyl and propyloxymethyl.

In the case of R₃, alkenyl is to be understood as meaning straight-chain or branched alkenyl, for example vinyl, allyl, methallyl, 1-methylvinyl or but-2-en-l-yl; preferably alkenyl radicals having a chain length of 2 to 3 carbon atoms.

In the case of R₃ alkynyl is to be understood as straight-chain or branched alkynyl, for example ethynyl, propargyl, 1-methylpropargyl, but-2-yn-l-yl or but-3-yn-l-yl.

Substituted or unsubstituted phenyl in the radical R₃ is a phenyl ring which is substituted by 1 to 3 substituents, in particular halogen atoms, C_rC₃alkyl, C_rC₃haloalkyl, C C₃alkoxy, ^haloalkoxy, C₁-C₃alkanoyl, C_rC₃alkoxycarbonyl or cyano, or may be 1 to 2 nitro groups.

Examples of the cycloalkyl radicals X and Y which are suitable as substituents are cyclopropyl, cyclobutyl, cyclopentyl or cyclohexyl, preferably cyclopropyl.

The invention also embraces the salts of the compounds of the formula I, being sulfonamides with an acidic proton, can form with amines, alkali metal bases and alkaline earth metal bases or quaternary ammonium bases.

Amongst alkali metal hydroxides and alkaline earth metal hydroxides used in salt formation, the hydroxides of lithium, sodium, potassium, magnesium or calcium are preferred and particularly preferred are those of sodium or potassium.

Examples of amines which are suitable for salt formation are primary, secondary and tertiary aliphatic and aromatic amines such as methylamine, ethylamine, n-propylamine, isopropylamine, the four isomeric butylamines, n-amylamine, iso-amylamine, hexylamine, heptylamine, octylamine, nonylamine, decylamine, pentadecylamine, hexadecylamine, heptadecylamine, octadecylamine, methylethylamine, methylisopropylamine, methylehexylamine, methylnonylamine, methylpentadecylamine, methyloctadecylamine, ethylbutylamine, ethylheptylamine, ethyloctylamine, hexylheptylamine, hexyloctylamine, dimethylamine, diethylamine, di-n-propylamine, diisopropylamine, di-n-butylamine, di-n-amylamine, diisoamylamine, dihexylamine, diheptylamine, dioctylamine, ethanolamine, n-propanolamine, iso-propanolamine, N,N-diethylethanolamine, 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, diethanolamine, trimethylamine, triethylamine, tri-n-propylamine, triisopropylamine, tri-n-butylamine, tri-isobutylamine, tri-sec-butylamine, tri-n-amylamine; heterocyclic amines for example pyridine, quinoline, iso-quinoline, morpholine, piperidine, pyrrolidine, indoline, quinuclidine and azepine; primary arylamines, for example anilines, methoxyanilines, ethoxyanilines, o,m,p-toluidines, phenylenediamines, benzidines, naphthylamines and o,m,p-chloroanilines; but in particular ethyl-, propyl-, diethyl- or triethylamine, but especially iso-propylamine and diethanolamine.

Examples of quaternary ammonium bases are generally the cations of haloammonium salts, for example the tetramethylammonium cation, the trimethylbenzylammonium cation, the triethylbenzylammonium cation, the tetraethylammonium cation, the trimethylethylammomum cation, but also the ammonium cation.

Preferred are the compounds of the formula la

i.e. R_! is in the 2-position, R₂ the 3-, 4- or 5-position, and the oxetan-3-oxycarbonyl radical in the 6-position of the phenyl- 1-amidosulfonyl ring. Particularly preferred, amongst these compounds of the formula la are those in which the radical R₂ is in the 3- or 5-position, and R₄, R₅, R₆, R and R₈ independently of one another are hydrogen or methyl, in particular hydrogen.

Other preferred compounds are those of the formula lb

i.e. R_: is in the 2-position, R₂ in the 4-, 5- or 6-position and the oxetan-3-oxycarbonyl radical is in the 3-position of the phenyl- 1-amidosulfonyl ring. Particularly preferred amongst these compounds of the formula lb are those in which the radical R₂ is in the 6-position, and R₄, R₅, Rg, R₇ and are R₈ independently of one another are hydrogen or methyl, in particular hydrogen.

Especially preferred are the compounds of the formula I, la or lb in which the radical R₂ is hydrogen, fluorine, chlorine, bromine, methyl, methoxy or nitro.

Important compounds of the formula I, la or lb, including the preferred meanings, are those in which the radicals Rj and R₂ independently of one another are hydrogen, fluorine, chlorine, bromine, Cx-Qalkyl, C_j-C^aloalkyl or nitro. Particularly preferred amongst these compounds of the formula I, la or lb are those in which Rj and R₂ independently of one another are fluorine, chlorine, bromine, methyl, ethyl, trifluoromethyl or nitro.

Especially important compounds of the formula I, la or lb, including all of the preferred meanings, are those in which the radicals X are hydrogen, methyl or cyclopropyl; and the radicals Y are methyl or cyclopropyl.

Compounds of the formula I, la or lb which must be emphasised are the following, in which Rj is hydrogen, fluorine, chlorine, bromine, methyl, ethyl or trifluoromethyl; R₂ is hydrogen, fluorine, chlorine, methyl or methoxy; R₄, R₅, Rg, R₇ and R₈ independently of one another are hydrogen or methyl; and X and Y independently of one another are hydrogen, methyl or cyclopropyl.

The process according to the invention for the preparation of the compounds of the formula I and salts thereof is analogous to known processes and comprises reacting an oxetan-3-oxycarbonylaniline of the formula II

R₇ in which R R , R₄, R₅, R₆, R₇ and R₈ are as defined in formula I with a l,2,4-triazolo[l,5-a]pyrimidine-2-sulfonyl chloride of the formula III

in which X and Y are as defined in formula I, in an inert organic solvent in the presence of a base. This process is particularly suitable for oxetan-3-oxycarbonylanilines which have activating substituents, i.e. substituents which are electron donors, for example alkyl and alkoxy groups.

Another process in three steps for the preparation of the compounds of the formula I follows the equation:

vm iv

An alkoxycarbonylphenyl-l,2,4-triazolo[l,5-a]pyrimidine-2-sulfonamide of the formula VIII in which R_l5 R₂, X and Y are as defined in formula I and R₉ is C_rC₄alkyl is hydrolysed with base catalysis to give the hydroxycarbonylphenyl-l,2,4-triazolo[l,5-a]pyrimidine-2-sulfonamide of the formula IV in which R R₂, X and Y are as defined above.

In a second reaction step, this intermediate of the formula IV is converted in the presence of 1-hydroxybenzotriazole and the acidic carbodiimide reagent

N-ethyl-N'-(3-dimethylaminopropyl)-carbodiimide hydrochloride into the activated ester phenyl-(benzotriazol- 1 -yl-oxycarbonyl)- 1 ,2,4-triazolo[ 1 ,5-a]pyrimidine-2-sulf onamide of the formula V in which R R₂, X and Y are as defined above. In a third reaction step, this ester of the formula V is reacted with 3-oxetanol of the formula IX in which R₄, R₅, R₆, R₇ and R₈ are as defined in formula I, in a polar organic solvent at increased temperature to give the compounds of the formula I.

This second process for the preparation of the compounds of the formula I is preferred in those cases where the oxetan-3-oxycarbonylanilines of the formula II are not accessible or cannot be reacted, or only with difficulty, with the l,2,4-triazolo[l,5-a]pyrimidine-2-sulfonyl chlorides of the formula HI according to the first one-step process due to electron-attracting substituents R_j, R₂, for example nitro, S(0)₂R₃ or halogen. Such reactions of carboxylic acids which have an additional acidic group (the sulfonamide group in the abovementioned case) with the acidic carbodiimide reagent N-ethyl-N'-(3-dimethylaminopropyl)-carbodiimide hydrochloride, are described in J. Org. Chem. 47, 1962 (1982) and M. Bodansky & A. Bodansky, "The Practice of Peptide Synthesis", p. 145, Springer Verlag 1984, in Volume 21 in the series "Reactivity and Structure, Concepts in Organic Chemistry".

The reactions which give compounds of the formula I are advantageously carried out in aprotic, inert, organic solvents. Such solvents are hydrocarbons such as benzene, toluene, xylene, hexane or cyclohexane, chlorinated hydrocarbons such as dichloromethane, trichloromethane, tetrachloromethane or chlorobenzene, ethers such as diethyl ether, ethylene glycol dimethyl ether, diethylene glycol dimethyl ether, tetrahydrofuran or dioxane, nitriles such as acetonitrile or propionitrile, amides such as dimethylformamide, diethylformamide or N-methylpyrrolidone, and esters such as ethyl acetate. The reaction temperatures are preferably between -10°C and +150°C.

The reactions are generally not, or only weakly, exothermal and can be carried out between 0°C and room temperature. To shorten the reaction time or else to trigger the reaction, it is expedient to heat the reaction mixture briefly at boiling point. The reaction times can also be shortened by adding either catalytic amounts or up to 2 equivalents of a base as reaction catalyst. Bases which are suitable are, in particular, tertiary amines such as trimethylamine, triethylamine, quinuclidine, l,4-diazabicyclo-(2,2,2)-octane, l,5-diazabicyclo(4,3,0)non-5-ene or l,5-diazabicyclo(5,4,0)undec-7-ene or pyridine and 4-(N,N-dimethylamino)-pyridine. Alternatively, inorganic bases such as hydrides, for example sodium hydride or calcium hydride, hydroxides, for example sodium hydroxide and potassium hydroxide, carbonates, for example sodium carbonate and potassium carbonate, or hydrogen carbonates, for example potassium hydrogen carbonate and sodium hydrogen carbonate, can also be used as bases.

Heterogeneous catalysis with transition metals, for example palladium, platinum or nickel (Raney nickel) in absolute, inert, organic solvents, for example tetrahydrofuran or dioxane, is preferably suitable for catalytic hydrogenation.

The end products of the formula I can be isolated by concentration and/or by evaporation of the solvent and purified by recrystallisation or trituration of the solid residue in solvents in which they are not readily soluble, for example ethers, esters, aromatic hydrocarbons or chlorinated hydrocarbons. A further possibility for isolating and purifying the products of the formula I is by means of (flash) silica gel chromatography with the aid of a suitable solvent or solvent mixture, for example ethyl acetate, hexane or tetrahydrofuran.

The intermediates of the formula II are novel and were developed specifically for synthesising the compounds of the formula I. They are therefore part of the present invention.

The novel intermediates oxetan-3-oxycarbonylanilines of the formula II can be prepared by a range of standard processes known from the literature, for example by the following equation:

Accordingly, the compounds of the formula II are obtained by reacting a nitrobenzoic acid derivative of the formula VII in which Rj and R₂ are as defined in formula I with N,N-bis(2-oxo-3-oxazolidinyl)phosphinic acid chloride (see Synthesis 1980, 547), or thionyl chloride, oxalyl chloride and 3-oxetanol of the formula IX in which R₄, R₅, R₆, R₇ and R₈ are as defined in formula I, in the presence of a suitable base, for example triethylamine, to give a compound of the formula VI in which R_lτ R₂, R₄, R₅, R₆, R₇ and R₈ are as defined in formula I, and subsequently subjecting this intermediate to catalytic hydrogenation in an inert solvent.

The intermediates oxetan-3-oxycarbonylnitrobenzenes of the formula VI are also novel and accordingly a further part of the present invention.

The same preferred meanings with respect to R_{l t} R₂, R₄, R₅, R₆, R₇ and R₈ as in the compounds of the formula I apply to the two intermediates of the formulae II and VI.

The starting compounds required for the preparation processes are either known or can be prepared readily from known compounds. The 3-oxetanols of the formula IX

in which R₄, R₅, R₆, R₇ and Rg independently of one another are hydrogen or methyl are known from the literature; see J. Org. Chem. 48, 2953 (1983); J. Am. Chem. Soc. 112, 3535 (1990); Tetrahedron Lett. 30, 2505 (1969); Bull. Chem. Soc. Japan 62, 2032 (1989); and J. Am. Chem. Soc. 77, 4430 (1955).

The l,2,4-triazolo[l,5-a]pyrimidinesulfonyl chlorides of the formula III

are described in US-A-4 818 273 and EP-A-387 508.

The carboxylic acid derivatives of the formula VIII

in which R₉ is hydrogen or C_rC₄alkyl are disclosed in US-A-4 818 273 and EP-A-434 624.

As a rule, the active ingredients of the formula I are successfully applied at application rates from 0.001 to 2 kg/ha, in particular 0.005 to 1 kg/ha. The dosage rate required for the desired effect can be determined by experiments. It depends on the type of action, the development stage of the crop plant and of the weed and on the application (location, time, method) and can vary within wide ranges due to these parameters.

The compounds of the formula I are distinguished by growth-inhibiting and herbicidal properties which make them outstandingly suitable for use in crops of useful plants, in particular in cereals, cotton, soya beans, oilseed rape, maize and rice, the use in cotton, soya crops and cereals being very particularly preferred. Weeds in cotton and soya crops are preferably controlled pre- and post-emergence. The compounds of the formula I are distinguished in particular by the fact that they are readily degraded.

The invention also relates to herbicidal compositions which comprise a novel active ingredient of the formula I and to a method for inhibiting the growth of plants.

A method for inhibiting plant growth is understood as meaning controlling the natural development of the plant without altering the life cycle of the plant, which is determined by its genetic make-up, in the sense of a mutation. The method of growth inhibition is applied at a particular point in time of the development of the plant, which is to be determined in the particular case. The active ingredients of the formula I can be applied before or after emergence of the plants, for example even to the seeds or seedlings, to roots, tubers, stalks, leaves, flowers or other parts of the plants. This can be effected, for example, by applying the active ingredient, as pure active ingredient or in the form of a composition, to the plants and/or by treating the nutrient substrate of the plant (soil).

Various methods and techniques are suitable for using the compounds of the formula I or compositions comprising them for inhibiting plant growth, for example the following:

i) Seed treatment a) The seeds are treated with an active ingredient formulated as a wettable powder by shaking in a container until the seed surface is uniformly covered (dry seed treatment). Up to 4 g of active ingredient of the formula I are used per kg of seed in this method (up to 8.0 g of wettable powder in the case of a 50 % formulation).

b) The seeds are treated with an emulsion concentrate of the active ingredient or with an aqueous solution of the active ingredient of the formula I formulated as a wettable powder, using method a) (wet seed treatment).

c) Seed treatment by immersing the seeds in a liquor containing up to 1000 ppm of active ingredient of the formula I for 1 to 72 hours, which, if desired, is followed by drying the seeds (seed soaking).

Naturally, seed treatment or treatment of the germinated seedling are the preferred application methods since the treatment with active ingredient is directed entirely at the target crop. As a rule, 0.001 g to 4.0 g of active ingredient are used per kg of seed, but it is possible to deviate from the limit concentrations given in both directions, depending on the method chosen which also makes possible the addition of other active ingredients or micronutrients (repeated seed treatment).

ii) Controlled release of active ingredient

The dissolved active ingredient is applied to mineral granule carriers or polymerized granules (urea/formaldehyde) and allowed to dry. If desired, a coating can be applied

(coated granules), which permits controlled release of the active ingredient over a certain period.

The compounds of the formula I are employed in unaltered form, as obtained from synthesis or preferably together with the auxiliaries conventionally used in the art of formulation, and they are therefore processed in a known manner to give, for example, emulsion concentrates, directly sprayable or dilutable solutions, dilute emulsions, wettable powders, soluble powders, dusts, granules, and also encapsulations, for example in polymeric substances. The application methods, such as spraying, atomizing, dusting, wetting, scattering or pouring, as well as the kind of the compositions are selected to suit the intended aims and the prevailing circumstances.

The formulations, i.e. the compositions, preparations or combinations comprising the active ingredient of the formula I and, if desired, one or more solid or liquid additives, 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, if desired, surface-active compounds (surfactants).

The following are possible as solvents: aromatic hydrocarbons, in particular the fractions Cg to C₁₂, such as mixtures of alkylbenzenes, for example xylene mixtures or alkylated naphthalenes; aliphatic and cycloaliphatic hydrocarbons such as paraffins, cyclohexane or tetrahydronaphthalene; alcohols such as ethanol, propanol or butanol; glycols as well as their ethers and esters, such as propylene glycol or dipropylene glycol ethers, ketones such as cyclohexanone, isophorone or diacetone alcohol, strongly polar solvents such as N-methyl-2-pyrrolidone, dimethyl sulfoxide or water; vegetable oils as well as esters thereof, such as rapeseed, castor or soya oil; or, if desired, silicone oils. Solid carriers which are generally used, for example for dusts and dispersible powders, are ground natural minerals, such as calcite, talc, kaolin, montmorillonite or attapulgite. To improve the physical properties, it is also possible to add highly-disperse silicas or highly-disperse absoηptive polymers. Possible paniculate, adsorptive carriers for granules are either porous types, for example pumice, brick grit, sepiolite or bentonite, or non-sorptive carrier materials, such as calcite or sand. Moreover, a large number of pregranulated materials of inorganic or organic nature can be used, such as, in particular, dolomite or comminuted plant residues.

Suitable surface-active compounds are non-ionic, cationic and/or anionic surfactants having good emulsifying, dispersing and wetting properties, depending on the nature of the active ingredient of the formula I to be formulated. Surfactants are also to be understood as meaning mixtures of surfactants.

Anionic surfactants which are suitable can be either so-called wa;: -soluble soaps or water-soluble synthetic surface-active compounds.

Suitable soaps which may be mentioned are the alkali metal salts, alkaline earth metal salts or substituted or unsubstituted ammonium salts of higher fatty acids (C^-C^ such as the sodium salts or potassium salts of oleic or stearic acid, or of natural mixtures of fatty acids which can be obtained, for example, from coconut or tallow oil. Mention must also be made of the fatty acid methyltaurinates.

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

The fatty alcohol sulfonates or fatty alcohol sulfates are as a rule in the form of alkali metal salts, alkaline earth metal salts or substituted or unsubstituted ammonium salts, and have an alkyl radical having 8-22 C atoms, alkyl also including the alkyl moiety of acyl radicals, for example the sodium or calcium salt of ligninsulfonic acid, of the dodecylsulfuric ester or of a fatty alcohol sulfate mixture prepared from natural fatty acids. This group also includes the salts of the sulfuric esters and sulfonic acids of fatty alcohol/ethylene oxide adducts. The sulfonated benzimidazole derivatives preferably contain 2 sulfonyl groups and one fatty acid radical having 8 to 22 C atoms. Examples of alkylarylsulfonates are the sodium/calcium or triethanolamine salts of dodecylbenzenesulfonic acid, of dibutylnaphthalenesulfonic acid or of a naphthalenesulfonic acid/formaldehyde condensation product.

Other suitable compounds are the corresponding phosphates, such as the salts of the phosphoric ester of a p-nonylphenol/(4-14)-ethylene oxide adduct, or phospholipids.

Suitable non-ionic surfactants are mainly polyglycol ether derivatives of aliphatic or cycloaliphatic alcohols, saturated or unsaturated fatty acids and alkylphenols, which can contain 3 to 30 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.

Other non-ionic surfactants which are suitable are the water-soluble polyethylene oxide adducts with polypropylene glycol, ethylenediaminopolypropylene glycol and alkylpolypropylene glycol which have 1 to 10 carbon atoms in the alkyl chain and which contain 20 to 250 ethylene glycol ether groups and 10 to 100 propylene glycol ether groups. The abovementioned compounds customarily contain 1 to 5 ethylene glycol units per propylene glycol unit.

Examples of non-ionic surfactants which may be mentioned are nonylphenol polyethoxyethanols, castor oil polyglycol ethers, polypropylene/polyethylene oxide adducts, tributylphenoxypolyethoxyethanol, polyethylene glycol and octylphenoxypolyethoxyethanol.

Other suitable substances are fatty acid esters of polyoxyethylene sorbitan, such as polyoxyethylenesorbitan trioleate.

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

The surfactants customary in the art of formulation are described, inter alia, in the following publications:

"Mc Cutcheon's Detergents and Emulsifiers Annual" Mc Publishing Corp., Glen Rock, New Jersey, 1988; M. and J. Ash, "Encyclopedia of Surfactants", Vol. I-iπ, Chemical Publishing Co., New York, 1980-1981.

Dr. Helmut Stache, "Tensid-Taschenbuch [Surfactant Guide]", Carl Hanser Verlag, Munich, Vienna, 1981.

As a rule, the pesticidal preparations comprise 0.1 to 99 , in particular 0.1 to 95 %, of the active ingredient of the formula 1, 1 to 99 % of a solid or liquid additive and 0 to 25 %, in particular 0.1 to 25 %, of a surfactant.

While concentrated compositions are more preferred as commercial products, the end user, as a rule, applies dilute compositions.

The compositions can also comprise further additives such as stabilisers, for example epoxidised or unepoxidised vegetable oils (epoxidised coconut oil, rapeseed oil or soya oil), defoamers, for example silicone oil, preservatives, viscosity regulators, binders, tackifiers as well as fertilisers or other active ingredients for achieving specific effects.

In particular, preferred formulations have the following composition: (% = percent by weight).

Emulsifiable concentrates:

Active ingredient: 1 to 90 %, preferably 5 to 50 %

Surfactant: 5 to 30 %, preferably 10 to 20 %

Liquid carrier: 15 to 94 %, preferably 70 to 85 %

Dusts:

Active ingredient: 0.1 to 10 %, preferably 0.1 to 1 %

Solid carrier: 99.9 to 90 %, preferably 99.9 to 99 %

Suspension concentrates:

Active ingredient: 5 to 75 %, preferably 10 to 50 %

Water: 94 to 24 %, preferably 88 to 30 % Surfactant: 1 to 40 %, preferably 2 to 30 % Wettable powders:

Active ingredient: 0.5 to 90 %, preferably 1 to 80 %

Surfactant: 0.5 to 20 %, preferably 1 to 15 %

Solid carrier material: 5 to 95 %, preferably 15 to 90 %.

Granules: Active ingredient: 0.5 to 30 %, preferably 3 to 15 % Solid carrier: 99.5 to 70 %, preferably 97 to 85 %.

Formulation examples of liquid active ingredients of the formula I (% = percent by weight)

1. Emulsion concentrates a) b) c)

Active ingredient as per

Tables 1 and 2 25% 40% 50%

Calcium dodecylbenzenesulfonate 5% 6%

Castor oil polyethylene glycol ether (36 mol of EO) 5%

Tributylphenol polyethylene glycol ether (30 mol of EO)

Cyclohexanone

Xylene mixture 65%

Emulsions of any desired concentration can be prepared from such concentrates by diluting them with water.

2. Solutions a) b) c) d)

Active ingedient as per

Tables 1 and 2 80% 10% 5% 95%

Propylene glycol monomethyl ether 20%

Polyethylene glycol MW 400 70%

N-Methyl-2-pyrrolidone 20%

Epoxidised coconut oil 1% 5%

Petroleum spirit (boiling range 160-190°C) 94%

The solutions are suitable for use in the form of microdrops.

3. Granules a) b) c) )

Active ingredient as per

Tables 1 and 2

Kaolin

Highly-disperse silicic acid

Attapulgite

The active ingredient is dissolved in methylene chloride, the solution is sprayed onto the carrier, the solvent is subsequently evaporated in vacuo.

4. Dusts a) b)

Active ingredient as per

Tables 1 and 2

Highly-disperse silicic acid

Talc

Kaolin 90%

Ready-for-use dusts are obtained by intimately mixing the carriers with the active ingredient. li

Formulation examples of solid active ingredients of the formula I (% = percent by weight)

5. Wettable powders a) b) c) Active ingredient as per Tables 1 and 2 Sodium ligninsulfonate Sodium lauryl sulfate

Sodium diisobutylnaphthalene- sulfonate - 6% 10%

Octylphenol polyethylene glycol ether (7-8 mol of EO) - 2%

Highly-disperse silicic acid 5% 10% 10%

Kaolin 62% 27%

The active ingredient is mixed thoroughly with the additives, and the mixture is ground thoroughly in a suitable mill. This gives wettable powders which can be diluted with water to give suspensions of any desired concentration.

6. Emulsion concentrate Active ingredient as per

Tables 1 and 2 10%

Octylphenol polyethylene glycol ether (4-5 mol of EO) 3%

Calcium dodecylbenzenesulfonate 3%

Castor oil polyglycol ether

(36 mol of EO) 4%

Cyclohexanone 30%

Xylene mixture 50%

Emulsions of any desired concentration can be prepared from this concentrate by diluting it with water. 7. Dusts a) b) Active ingredient as per

Tables 1 and 2 5% 8%

Talc 95%

Kaolin - 92%

Ready-for-use dusts are obtained by mixing the active ingredient with the carriers and grinding the mixture on a suitable mill.

8. Extruder granules Active ingredient as per

Tables 1 and 2 10%

Sodium ligninsulfonate 2%

Carboxymethylcellulose 1%

Kaolin 87%

The active ingredient is mixed with the additives, and the mixture is ground and moistened with water. This mixture is extruded and subsequently dried in a stream of air.

9. Coated granules Active ingredient as per

Tables 1 and 2 3%

Polyethylene glycol (MW 200) 3%

Kaolin 94%

In a mixer, the finely ground active ingredient is applied uniformly to the kaolin which has been moistened with polyethylene glycol. Dust-free coated granules are obtained in this manner.

10. Suspension concentrate Active ingredient as per

Tables 1 and 2 40%

Propylene glycol 10% Nonylphenol polyethylene glycol ether (15 mol of EO) 6%

Sodium ligninsulfonate 10% Carboxymethylcellulose 1% Silicone oil in the form of a 75% aqueous emulsion 1% Water 32

The finely ground active ingredient is mixed intimately with the additives. A suspension concentrate from which suspensions of any desired concentration can be prepared by dilution with water is obtained in this manner.

Preparation Examples

Example HI: Preparation of 5,7-dimethyl-N-[2-methyl-6-(3-oxetanyl)- oxycarbonylphen yl] - 1 ,2,4-triazolof 1 ,5-a] -pyrimidine-2-sulfonamide

3.1 g of 3-oxetanyl 3-methylanthranilate (cf. Preparation Examples H5 and H6) and 3.7 g of 5,7-dimethyl-l,2,4-triazolo-[l,5-a]-pyrimidine-2-sulfonyl chloride are stirred for 20 hours at room temperature in 5 ml of pyridine and 5 ml of ethyl acetate. The reaction mixture is poured into ice- water and extracted twice using ethyl acetate. The organic phase is washed in each case once with water, 2N hydrochloric acid, water and saturated sodium chloride solution, dried over sodium sulfate and concentrated. The crude product is subjected to flash chromatography over a silica gel column using ethyl acetate/hexane 9/1. The desired product 5,7-dimethyl-N-[2-methyl-6-(3-oxetanyl)-oxycarbonyl- phenyl]-l,2,4-triazolo[l,5-a]pyrimidine-2-sulfonamide has a melting point of 174-175°C. Example H2:

5-Methyl-7-cvcloρropyl-N-(2-chloro-6-hvdroxycarbonylphenyl)-l,2,4-triazolo- T 1 ,5-a]pyrimidine-2-sulfonamide (Intermediate)

4.1 g of 5-methyl-7-cyclopropyl-N-(2-chloro-6-methoxycarbonylphenyl)-l,2,4-triazolo- [l,5-a]pyrimidine-2-sulf onamide are stirred for 2.5 hours at 60-65°C in 100 ml of 2N sodium hydroxide solution. The mixture is brought to a pH of 2.8 with the aid of half-concentrated hydrochloric acid which is added dropwise while the mixture is cooled to 0-5°C. The product which has precipitated is filtered off, washed with buffer solution (pH 3) and dried over phosphorus pentoxide in a vacuum desiccator at 70°C. 3.48 g of the desired 5-methyl-7-cyclopropyl-N-(2-chloro-6-hydroxycarbonylphenyl)- 1 ,2,4-triazolo- [l,5-a]pyrimidine-2-sulfonamide of melting point >215°C (decomposition) are obtained.

Example H3:

5-Methyl-7-cvclopropyl-N-r2-chloro-6-(benzotriazol-l-yloxycarbonyl)-phenyll- 1 ,2,4-triazolor 1 ,5-a1pyrimidine-2-sulfonamide (Intermediate)

4.76 g of 5-methyl-7-cyclopropyl-N-(2-chloro-6-hydroxycarbonylphenyl)-l,2,4-triazolo- [l,5-a]pyrimidine-2-sulfonamide and 1.69 g of dry 1-hydroxybenzotriazole in 100 ml of dichloromethane are treated, with ice-cooling, with 2.51 g of N-ethyl-N'-(3-dimethylaminopropyl)-carbodiimide hydrochloride, and the mixture is stirred for 1.5 hours. A clear, dark yellow solution results, and this is heated to room temperature and left to stand overnight. The reaction solution is washed in each case twice with buffer solution (pH 5.12) and saline, dried and evaporated, and the product is subjected to flash chromatography on 200 g of silica gel with tetrahydrofuran as eluent and recrystallised from ethyl acetate. 3.1 g of the desired 5-methyl-7-cyclopropyl- N-[2-chloro-6-(benzotriazol-l-yloxycarbonyl)-phenyl]-l,2,4-triazolo[l,5-a]pyrimidine-2- sulfonamide of melting point 180-185°C are obtained. Example H4:

5-Methyl-7-cvclopropyl-N-r2-chloro-6-(3-oxetanyl)-oxycarbonylphenyl1-l,2,4-triazolo- T 1 ,5-a1pyrimidine-2-sulfonamide

1.9 g of 5-methyl-7-cyclopropyl-N-[2-chloro-6-benzotriazol-l-yloxycarbonyl)-phenyl]- l,2,4-triazolo[l,5-a]pyrimidine-2-sulfonamide and 1.2 g of 3-oxetanol (content 80%) are refluxed for 76 hours in 50 ml of acetonitrile. The reaction mixture is evaporated, and the product is subjected to flash chromatography on 250 g of silica gel using ethyl acetate/ tetrahydrofuran 18/4. The product is recrystallised from ethyl acetate and dried for 3 hours under a high vacuum at 100-110°C (removal of crystal solvent). 0.79 g of the desired 5-methyl-7-cyclopropyl-N-[2-chloro-6-(3-oxetanyl)-oxycarbonylphenyl]-l,2,4- triazolo[l,5-a]pyrimidine-2-sulfonamide of melting point 187-190°C is obtained.

Example H5: 3-Oxetanyl 3-methyl-2-nitrobenzoate (Intermediate)

17.0 g of 3-methyl-2-nitrobenzoic acid, 7.5 g of 3-oxetanol (content 92%) and 18.7 g of triethylamine are introduced into 200 ml of dichloromethane. 23.7 g of N,N-bis[2-oxo-3-oxazolidinyl]-phosphinic acid chloride are added in one portion with vigorous stirring and cooling to 15°C. The ice-bath is removed after 10 minutes; the reaction temperature rises slowly to +30°C. After 2 hours, a clear solution is obtained which is left to stand overnight. The reaction solution is washed twice using saturated sodium bicarbonate solution as well as saline, dried over sodium sulfate, and the solvent is evaporated. The residue obtained is dissolved in a mixture of diethyl ether/ethyl acetate. This solution is treated with active charcoal while hot. The crude product is concentrated, then recrystallised from ether, and washed with an ether/pentane mixture. 12.5 g of the desired 3-oxetanyl 3-methyl-2-nitrobenzoate of melting point 78-80°C are obtained.

Example H6: 3-Oxetanyl 3-methylanthranilate (Intermediate)

12.0 g of 3-oxetanyl 3-methyl-2-nitrobenzoate in 150 ml of tetrahydrofuran are hydrogenated with 2.5 g of Raney nickel under atmospheric pressure, and 2 more ponions of catalyst of 2.5 g each are added in the course of the reaction. The catalyst is subsequently filtered off, and the tetrahydrofuran is evaporated. The crystalline residue is stirred with ether and filtered off. After drying at 40°C, 7.9 g of the desired 3-oxetanyl 3-methylanthranilate of melting point 90-92°C are obtained.

The compounds of the formulae la and lb which are listed in the following Tables 1, 2 and 3, as well as the intermediates thereof, are prepared analogously.

Comp.

Comp.

2.01 2.02

2.04 2.05

2.06

2.07

2.08

2.09 2.10

2.11

2.12 2.13

Table 3: Intermediates of the formula

Comp. No. R-. Physical data

3.01 m.p. 59-63°C 3.02 m.p. 121-122°C 3.03 m.p. 125-128°C 3.04 m.p. 78-79°C 3.05 m.p. 78-80°C 3.06 m.p. 90-92°C 3.07 no⁵ 1.5683 3.08

m.p. 64-65°C

Biological examples

Example B 1 : Herbicidal activity, preemergence

In a greenhouse, test plants are sown into seed dishes, and the soil surface is immediately afterwards treated with an aqueous spray mixture prepared with a suspension concentrate

(Formulation Example No. 10) corresponding to an application rate of 4 kg or 0.5 kg of active ingredient/hectare. The seed dishes are kept in the greenhouse at 22-25°C and

50-70% relative atmospheric humidity.

After 3 weeks, the herbicidal activity is assessed using a nine-step rating system (1 = total damage, 9 = no action) by comparison with an untreated control group.

Ratings from 1 to 4 (in particular 1 to 3) suggest a good to very good herbicidal activity. Ratings from 6 to 9 (in paπicular from 7 to 9) suggest a good tolerance (in particular in the case of crop plants). Test plants: Avena, Setaria, Sinapis and Stellaria.

In this test, the compounds of the formula I according to the examples in Tables 1 and 2 show a powerful herbicidal activity.

The same results are obtained when the abovementioned aqueous spray mixture is prepared with an emulsion concentrate (Formulation Examples Nos. 1 and 6), solutions (Formulation Example No. 2), granules (Formulation Example No. 3), dusts (Formulation Examples Nos. 4 and 7), wettable powders (Formulation Example No. 5), extruder granules and coated granules (Formulation Examples Nos. 8 and 9).

Table Bl shows examples of the good herbicidal activity of the compounds of the formula I.

Table Bl: Preemer ence action

After emergence, a number of monocotyledon and dicotyledon weeds (in the 4- to 6-leaf stage) are sprayed with an aqueous dispersion of active ingredient which has been prepared with a suspension concentrate (Formulation Example No. 10) at a dosage rate of 4 kg and 0.5 kg of active ingredient per hectare, and the plants are kept at 24°-26°C and 45-60% relative atmospheric humidity. 15 days after the treatment, the herbicidal activity is assessed using a nine-step rating system (1 = total damage, 9 = no action) in comparison with an untreated control group.

Test plants: Avena, Setaria, Sinapis and Stellaria.

In this test too, the compounds of the formula I according to the examples in Tables 1 and 2 show a good herbicidal activity.

Table B2 shows examples of the good herbicidal activity of the compounds of the formula I.

Table B2: Postemer ence action

and Monochoria vag. are sown in plastic beakers (surface area 60 cm², volume 500 ml). After sowing, the beakers are filled with water to the soil surface. 3 days after sowing, the water level is raised just above the soil surface (3-5 mm). Application is effected 3 days after sowing by spraying the test substances onto the containers. The dosage rate used corresponds to an amount of 8-500 g of active ingredient per hectare. The beakers with the plants are then placed in a greenhouse under optimum growth conditions for the rice weeds, i.e. at 25-30°C and high atmospheric humidity.

3 weeks after application, the tests are evaluated. The compounds of the formula I have a damaging effect on the weeds.

Claims

WHAT IS CLAIMED IS:

1. A triazolo[l,5-a]pyrimidine-2-sulfonamide of the formula I

in which Rj and R₂ independently of one another are hydrogen, halogen, C_rC alkyl, C]-C haloalkyl, C_rC alkoxy, C_rC₄haloalkoxy, C_rC alkoxy-C C₄-alkyl, nitro, phenyl or S(0)_nR₃; R₃ is C_rC₄alkyl, C]-C haloalkyl, C -C alkenyl, C₂-C₄alkynyl, benzyl or optionally substituted phenyl; n is the number 0, 1 or 2; R₄, R₅, R₆, R₇ and R₈ independently of one another are hydrogen or C_rC₄alkyl; and X and Y independently of one another are hydrogen, C_rC alkyl or C₃-C₆cycloalkyl; or an agrochemically acceptable salt of this compound, with the proviso that the radicals X and Y are not simultaneously hydrogen.

2. A compound according to claim 1, of the formula la

in which R_j, R₂, R₄ to Rg, X and Y are as defined in claim 1.

3. A compound according to claim 2, in which R₂ is in the 3- or 5-position.

4. A compound as claimed in any one of claims 2 or 3, in which R₄, R₅, R₆, R₇ and R₈ independently of one another are hydrogen or methyl, in particular hydrogen.

5. A compound according to claim 1, of the formula lb

in which Rj, R₂, R₄ to R₈, X and Y are as defined in claim 1.

6. A compound according to claim 5, in which R₂ is in the 6-position.

7. A compound according to any one of claims 5 or 6, in which R₄, R₅, R₆, R₇ and R₈ independently of one another are hydrogen or methyl, in particular hydrogen.

8. A compound according to any one of claims 1 to 7, in which R₂ is hydrogen, fluorine, chlorine, bromine, methyl, methoxy or nitro.

9. A compound according to any one of claims 1 to 8, in which R_j and R₂ independently of one another are hydrogen, fluorine, chlorine, bromine, C_rC₄alkyl, C₁-C haloalkyl or nitro.

10. A compound according to claim 9, in which R_j and R₂ independently of one another are fluorine, chlorine, bromine, methyl, ethyl, iso-propyl, trifluoromethyl or nitro.

11. A compound according to any one of claims 1 to 10, in which the radical X is hydrogen, methyl or cyclopropyl; and Y is methyl or cyclopropyl.

12. A compound according to any one of claims 1 to 7, in which R_! is hydrogen, fluorine, chlorine, bromine, methyl, ethyl, iso-propyl or trifluoromethyl; R₂ is hydrogen, fluorine, chlorine, methyl or methoxy; R₄, R₅, R₆, R₇ and R₈ independently of one another are hydrogen or methyl; and X and Y independently of one another are hydrogen, methyl or cyclopropyl.

13. A process for the preparation of a triazolo[l,5-a]pyrimidine-2-sulfonamide of the formula I according to claim 1, wherein an oxetan-3-oxycarbonylaniline of the formula II

R₇ in which R_j, R₂, R₄, R₅, R₆, R₇ and R₈ are as defined in claim 1 is reacted with a l,2,4-triazolo[l,5-a]pyrimidine-2-sulfonyl chloride of the formula III

in which X and Y are as defined in claim 1, in an inert organic solvent in the presence of a base.

14. A process for the preparation of a triazolo[l,5-a]pyrimidine-2-sulfonamide of the formula I according to claim 1, wherein a hydroxycarbonylphenyl-l,2,4-triazolo[l,5-a]pyrimidine-2-sulfonamide of the formula IV

in which R-., R₂, X and Y are as defined in claim 1, is convened in an inert organic solvent with 1-hydroxybenzotriazole in the presence of N-ethyl-N'-(3-dimethylaminopropyl)-carbodiimide hydrochloride into the phenyl-(benzotriazol- 1 -yloxycarbonyl)- 1 ,2,4-triazolo[ 1 ,5-a]pyrimidine-2-sulfonamide of the formula V

in which R_lf R₂, X and Y are as defined above, and this ester of the formula V is reacted with 3-oxetanol of the formula IX

in which R₄, R₅, R₆, R₇ and R₈ are as defined in claim 1, in a polar organic solvent to give a compound of the formula I.

15. An oxetan-3-oxycarbonylaniline of the formula II

R₇

in which R_1? R₂, R , R₅, R₆, R and R₈ are as defined in claim 1.

16. An oxetan-3-oxycarbonylnitrobenzene of the formula VI

in which Rj, R₂, R₄, R₅, R₆, R₇ and R₈ are as defined in claim 1.

17. A process for the preparation of the intermediate of the formula II according to claim 15, wherein a nitrobenzoic acid derivative of the formula VII

in which Rj and R₂ are as defined in claim 15 is reacted with

N,N-bis(2-oxo-3-oxazolidinyl)phosphinic acid chloride or with thionyl chloride or oxalyl chloride and 3-oxetanol of the formula IX

(IX),

in which R₄, R₅, R₆, R₇ and R₈ are as defined in claim 1, to give a compound of the formula VI

in which R-., R₂, R , R₅, R₆, R₇ and Rg are as defined above, and this intermediate is subsequently hydrogenated.

18. A herbicidal and plant-growth-inhibiting composition, which comprises at least one compound of the formula I according to claim 1.

19. A composition according to claim 18, which comprises between 0.1 % and 95 % of active ingredient of the formula I according to claim 1.

20. A method for controlling undesired plant growth, which comprises applying an effective amount of an active ingredient of the formula I according to claim 1, or a composition comprising this active ingredient, to the plants or their environment.

21. A method according to claim 20, wherein an amount of active ingredient of between 0.001 and 2 kg is applied per hectare.

22. A method for inhibiting the growth of plants, wherein an effective amount of an active ingredient of the formula I according to claim 1, or a composition comprising this active ingredient, is applied to the plants or their environment.

23. A method according to claim 20 for the selective pre- or postemergence control of weeds in crops of useful plants.

24. The use of a compound of the formula I according to claim 1 for the selective preemergence or postemergence control of weeds in crops of useful plants.

25. The use of a composition according to claim 18 for the selective preemergence or postemergence control of weeds in crops of useful plants.

FD 4.5 HW