# Patent

## Title
Herbicidal sulfonamides

## Abstract

A process for combating the growth of unwanted plants, wherein the soil or the plants are treated with a compound of the formula ##STR1## where Ar denotes substituted or unsubstituted phenyl or naphthyl, R.sup.1 denotes hydrogen or methyl, R.sup.2 denotes hydrogen or alkyl, R.sup.3 denotes alkyl, cycloalkyl, alkenyl, alkynyl, or substituted aralkyl, and Az denotes substituted or unsubstituted pyrazole, imidazole or triazole, or a metal complex thereof, and herbicides for carrying out the process.

## Background
The present invention relates to processes for combating the growth of unwanted plants with 2-aryloxy-2-azolylalkanecarboxyamides, herbicides containing them, and processes for the manufacture thereof.

The use of phenoxyalkanecarboxylic acid derivatives, e.g., the dimethylamine salt of 2,4-dichlorophenoxyacetic acid, as herbicides has been disclosed (R. Wegler, Chemie der Pflanzenschutz- und Schadlingsbekampfungsmittel ("Chemistry of crop protection agents and pesticides"), Vol. 5, Herbicide ("Herbicides"), 1977, p. 180). Their particular advantage is that they combat broadleaved plant species while leaving grasses and grassy crop plants substantially unaffected.

It has also been disclosed that 2-aryloxy-2-azolylalkanecarboxamides have a fungicidal action (German Laid-Open Application DE-OS 27 20 654). However, a herbicidal action of the compounds is not known.

We have now found that compounds of the formula ##STR2## where Ar denotes substituted or unsubstituted phenyl or naphthyl, R.sup.1 denotes hydrogen or methyl, R.sup.2 denotes hydrogen or C.sub.1 -C.sub.10 -alkyl, R.sup.3 denotes C.sub.1 -C.sub.10 -alkyl, cycloalkyl, cyclopropylmethyl, alkenyl, alkynyl, or unsubstituted or halogen-substituted aralkyl, and Az denotes unsubstituted or halogen- or methyl-substituted pyrazole, imidazole or triazole, and the metal complexes thereof, exhibit herbicidal and growth-regulating properties.

The compounds are effective both on broadleaved and grassy plants.

The manufacture of the compounds of the formula I is known: either appropriate 2-aryloxy-2-haloalkanecarboxamides are reacted with azoles; 2-aryloxy-2-azolylalkanecarboxylic acid esters are amidated (German Laid-Open Application DE-OS 27 20 654); or 2-aryloxy-2-azolylalkanecarboxylic acids--if desired after having been activated with, for example, thionyl chloride or thionyl diazoles--are reacted with amines (German Laid-Open Application DE-OS 28 46 038).

In formula I, Ar preferably denotes phenyl mono- or polysubstituted by halogen, C.sub.1 -C.sub.4 -alkyl, nitro, cyano, trifluoromethyl, chlorodifluoromethyl, trifluoromethylsulfonyl, benzyl or phenyl, e.g., 2-methyl-4-chlorophenyl, 2,4-dichlorophenyl, 3,5-dichlorophenyl, 2-bromo-4-chlorophenyl, 3,4-dichlorophenyl, 2,4,5-trichlorophenyl, 2,4-dinitrophenyl, 2-chloro-4-cyanophenyl, 4-fluorophenyl, 3-trifluoromethylphenyl, 3,5-dimethylphenyl, 4-benzylphenyl, o-diphenyl, p-diphenyl, 3-tert-butylphenyl and 4-tert-butylphenyl; or unsubstituted or halogen-substituted naphthyl, e.g., .alpha.-naphthyl, .beta.-naphthyl; R.sup.1 denotes hydrogen or methyl; R.sup.2 preferably denotes hydrogen, methyl or ethyl; R.sup.3 preferably denotes C.sub.1 -C.sub.10 -alkyl or C.sub.3 -C.sub.8 -cycloalkyl, e.g., methyl, ethyl, n-propyl, isopropyl, cyclopropyl, n-butyl, isobutyl, tert-butyl, cyclobutyl, n-pentyl, 2-pentyl, 3-pentyl, tert-amyl, neopentyl, 2-methylbutyl, 3-methylbutyl, 3-methyl-2-butyl, cyclopentyl, n-hexyl, 4-methyl-2-pentyl, 2,3-dimethylbutyl, 2-methyl-1-pentyl, 2-hexyl, 3-hexyl, 3-methyl-2-pentyl, 3-methylpentyl, 4-methylpentyl, 3-methyl-3-pentyl, 4,4-dimethylbutyl, cyclohexyl, heptyl, 2-heptyl, 3-heptyl, 4-heptyl, cycloheptyl, 1-octyl, 3-octyl, 4-octyl, 5-octyl, 5-ethyl-2-heptyl, 2,6-dimethyl-4-heptyl, 2,4-dimethyl-3-pentyl, 3-methyl-2-heptyl, nonyl, 6-ethyl-3-octyl, 2-methyl-2-pentyl, 2,3-dimethyl-2-butyl, 2-methyl-2-hexyl, 3-ethyl-3-pentyl, 3-methyl-3-hexyl, 2,3-dimethyl-2-butyl, 2,4-dimethyl-2-pentyl, 2,2,3-trimethyl-3-butyl, 2-methyl-2-heptyl, 4-methyl-4-heptyl, 2,4-dimethyl-2-hexyl, 2-methyl-2-octyl, 1-methyl-1-cyclopentyl, 1-methyl-1-cyclohexyl, 1-ethyl-1-cyclohexyl, and 2-methylnorborn-2-yl; C.sub.3 -C.sub.6 -alkenyl, e.g., allyl, methallyl, crotyl, 2-methylbut-2-en-1-yl, 2-methylbut-1-en-3-yl, hex-5-en-1-yl, and 2-methylbut-1-en-4-yl; C.sub.3 -C.sub.6 -alkynyl, e.g., propargyl, but-1-yn-3-yl, but-2-yn-1-yl, and 3-methylbut-1-yn-3-yl; and unsubstituted or halogen-substituted benzyl having  1 to 2 carbon atoms in the alkyl moiety and 6 to 10 carbon atoms in the aryl moiety, e.g., benzyl, p-chlorobenzyl, and .alpha.-phenylethyl; and Az preferably denotes unsubstituted or halogen- or methyl-substituted triazole.

In a particularly preferred class of compounds of the formula I, Ar denotes phenyl mono- or polysubstituted by halogen and/or methyl, R.sup.1 denotes hydrogen, R.sup.2 denotes hydrogen, and R.sup.3 denotes branched C.sub.3 -C.sub.7 -alkyl, e.g., isopropyl, isobutyl, tert-butyl, tert-amyl and 2,4-dimethylpent-3-yl.

Metal complexes are the complexes with salts of metals, e.g., copper, cobalt and chromium. The metal complexes are prepared by reaction of metal-free compounds with metal salts, e.g., in an organic solvent for the compound.

The active ingredients contain an asymmetrical carbon atom, and therefore form optically active isomers which may be prepared in conventional manner from the racemates formed during manufacture. The present invention relates not only to the racemates, but also to the individual optically active isomers.

Examples of the active ingredients are given in the following table. No. Ar          Az      R.sup.1 R.sup.2 R.sup.3     M.p. [.degree.C.] __________________________________________________________________________ 1  2,4-Dichlorophenyl ##STR3## H  H  i-C.sub.3 H.sub.7 50-53 2 "           "       CH.sub.3 "  " 3  "           "       H  "  tert.C.sub.4 H.sub.9 107-108 4 "           "       "  " ##STR4##   103-106 5 "           "       "  "  CH(i-C.sub.3 H.sub.7).sub.2 117-120 6 "           "       "  " ##STR5##   92-6 7 " ##STR6## "  "  tert.C.sub.4 H.sub.9 oil 8 " ##STR7## "  "  "           oil 9 " ##STR8## "  "  C(CH.sub.3).sub.2 CCH 112-115 10 "           "       "  CH.sub.3 CH.sub.3    148-150 11 "           "       "  "  CH.sub.2 CH(CH.sub.3).sub.2 106-108 12 "           "       "  H ##STR9##   71-75 13 4-Chlorophenyl "       "  "  tert.C.sub.4 H.sub.9 176-180 14 2,4,5-Trichlorophenyl "       "  "  "           128-131 15 4-Fluorophenyl "       "  "  "           90-94 16 4-Diphenyl  "       "  "  "           114-118 17 2-Diphenyl  "       "  "  "           142-146 18 4-Chlorophenyl "       "  "  C(CH.sub.3).sub.2 C CH 74-78 19 3,5-Dimethylphenyl "       "  "  tert.C.sub.4 H.sub.9 131-133 20 Phenyl ##STR10## "  "  "           142-144 21 " ##STR11## "  "  "           105-106 22 " ##STR12## "  "  "           oil 23 " ##STR13## "  "  "           101-103 24 2-Methyl-4-chlorophenyl "       "  "  "           119-122 25 4-tert.-butylphenyl "       "  "  "           126-129 26 4-Benzylphenyl "       "  "  "           102-105 27 .alpha.-Naphthyl "       "  CH.sub.3 CH.sub.3    90-92 28 "           "       "  C.sub.2 H.sub.5 C.sub.2 H.sub.5 82-83 29 "           "       "  H  tert.C.sub.4 H.sub.9 110-114 30 3-Trifluoromethylphenyl "       "  "  "           129-132 31 2,4-Dichlorophenyl "       "  "  CH.sub.2CH(CH.sub.3).sub.2 74-76 32 "           "       "  "  tert.C.sub.4 H.sub.9 172-176 CuCl.sub.2 complex 33 3-tert.-butylphenyl "       "  "  tert.C.sub.4 H.sub.9 97-99 34 3,5-Dimethylphenyl "       "  "  C(CH.sub.3).sub.2CCH 96-98 35 "           "       "  "  Benzyl      97-98 36 3,5-Dichlorophenyl "       "  "  tert.C.sub.4 H.sub.9 104-106 37 "           "       "  "  Benzyl      106-108 38 "           "       "  "  C(CH.sub.3)CCH 39 ##STR14##  "       "  "  tert.C.sub.4 H.sub.9 129-131 40 "           "       "  " ##STR15##  111-114 41 ##STR16##  "       "  " ##STR17##  118 42 "           "       "  " ##STR18##  105 (optically active water) 43 ##STR19##  "       "  " ##STR20##  102-103 44 "           "       "  " ##STR21##  102-105 45 ##STR22## ##STR23## "  "  tert.C.sub.4 H.sub.9 106-108 46 ##STR24##  "       "  "  "           140-144 47 ##STR25##  "       "  "  "           85-89 48 ##STR26##  "       "  "  "           107-112 49 ##STR27##  "       "  "  "           103-107 50 ##STR28##  "       "  "  CH.sub.2CH(CH.sub.3).sub.2 105-107 51 "           "       "  "  sec.-C.sub.4 H.sub.9 128-130 52 "           "       "  "  CH(CH.sub.3).sub. 2 128-130 53 "           "       "  " ##STR29##  180-182 54 ##STR30##  "       "  " ##STR31##  128-130 55 "           "       "  "  sec.-C.sub.4 H.sub.9 119-120 56 "           "       "  "  CH(CH.sub.3).sub.2 118-119 57 ##STR32##  "       "  " ##STR33##  105-108 58 ##STR34##  "       "  "  tert.-C.sub.4 H.sub.9 79-80 59 "           "       "  "  CH(CH.sub.3).sub.2 110-111 60 "           "       "  " ##STR35##  117-118 61 "           "       "  " ##STR36##  167-168 62 "           "       "  "  sec.-C.sub.4 H.sub.9 100-102 __________________________________________________________________________

The active ingredients can be converted into the conventional formulations, e.g. solutions, emulsions, suspensions, dusts, powders, pastes and granules. The form of application depends entirely on the purpose for which the agents are being used; it should, however, ensure a fine and uniform distribution of the active ingredient. The formulations are prepared in the conventional manner, for example by diluting the active ingredient with solvent and/or carriers, with or without the addition of emulsifiers and dispersants and, where water is used as the diluent, with or without organic auxiliary solvents. Suitable auxiliaries are, essentially, solvents, for example aromatics, e.g., xylene and benzene, chloroaromatics, e.g. chlorobenzene, paraffins, e.g. petroleum fractions, alcohols, e.g. methanol and butanol, amines e.g., ethanolamine, dimethylformamide, and water; solid carriers, for example natural rock powders, e.g., kaolin, alumina, talc and chalk, and synthetic rock powders, e.g. highly disperse silica and silicates; emulsifiers, for example non-ionic and anionic emulsifiers, e.g. polyoxyethylene fatty alcohol ethers, alkylsulfonates and arylsulfonates, and dispersants, for examle lignin, sulfite waste liquors and methylcellulose.

To initiate the herbicidal action, wetting agents, spreader-stickers and non-phytotoxic oils and oil concentrates may be added.

The herbicidal agents in general contain from 0.1 to 95% by weight of active ingredient, preferably from 5 to 90%.

Depending on the plants making up the weed flora, and their growth stages, application rates very from 0.1 to 15, and preferably from 0.2 to 5, kg of active ingredient per hectare. The higher rates are to be used for total elimination of vegetation.

The agents, and the ready-to-use preparations obtained therefrom, e.g., solutions, emulsions, suspensions, powders, dusts, pastes or granules, are applied in conventional manner, e.g. by spraying, atomizing, dusting, broadcasting, treating seed or watering.

Examples of such formulations are given below, N-methyl-.alpha.-pyrrolidone. A mixture is obtained which is suitable for application in the form of very fine drops. cyclohexanone. The mixture may be sprayed in the form of droplets. of 60 parts by weight of cyclohexanone, 20 parts by weight of isobutanol, and 10 parts by weight of the adduct of 40 moles of ethylene oxide to 1 mole of castor oil. 97 parts by weight of particulate kaolin. A dust is obtained containing 3% by weight of the active ingredient. a mixture consisting 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. A formulation of the active ingredient is obtained having good adherence. salt of dodecylbenzenesulfonic acid, 8 parts of a fatty alcohol polyglycol ether, 2 parts of the sodium salt of a phenolsulfonic acid-urea-formaldehyde condensate and 68 parts of a paraffinic mineral oil. A stable oily dispersion is obtained.

The active ingredients may be applied alone or in admixture among themselves or with other herbicides or other crop protection agents, e.g., agents for combating pests or phytopathogenic fungi or bacteria. The compounds may also be mixed with mineral salt solutions used to remedy nutritional or trace element deficiencies.

The action of the active ingredients on the growth of plants is demonstrated in greenhouse experiments.

The vessels employed were plastic flowerpots having a volume of 300 cm.sup.3, and which were filled with a sandy loam containing about 1.5% humus. The seeds of the test plants were sown shallow, and separately, according to species.

In the preemergence treatment, the active ingredients were immediately applied to the surface of the soil as a suspension or emulsion in water by spraying through finely distributing nozzles. The amount of active ingredient applied in this treatment was equivalent to 3.0 kg/ha.

After the agents had been applied, the vessels were lightly sprinkler-irrigated to induce germination and growth. Transparent plastic covers were then placed on the vessels until the plants had taken root. The cover ensured uniform germination of the plants, insofar as this was not impaired by the chemicals.

For the postemergence treatment, the plants were first grown in the vessels to a height of from 3 to 10 cm, depending on growth form, before being treated. For this treatment, either plants which had been sown directly in the pots and had grown there were selected, or plants which had been grown separately as seedlings and transplanted to the experiment vessels a few days before treatment. The amounts of active ingredient applied in this treatment were 0.5 and 1.0 kg/ha, and in somne cases 3.0 kg/ha.

The agents used for comparison purposes were the dimethylamine salt of 2,4-dichlorophenoxyacetic acid (A), at the same rates (based on acid), and (2,4-dichlorophenoxy)-(1,2,4-triazol-1-yl)-acetic acid amide (B) (German Laid-Open Application DE-OS 27 20 654), at the same rates.

No cover was placed on the vessels. The pots were set up in the greenhouse--species from warmer areas at from 20.degree. to 30.degree. C., and species from moderate climates at 15.degree. to 25.degree. C. The experiments were run for from 2 to 4 weeks. During this period, the plants were tended and their reactions to the various treatments assessed. The scale used for assessment was 0 t 100, 0 denoting no damage or normal emergence, and 100 denoting nonemergence or complete destruction of at least the visible plant parts.

The results reveal, on postemergence application in the greenhouse, the expected herbicidal action of comparative agent A on broadleaved unwanted plants, combined with slight damage to grasses and the grassy crop plant barley. When applied in the same manner, comparative agent B had no action at all on most of the test plants, and only a slight action here and there. By contrast, active ingredient no. 19 had, on postemergence application in the greenhouse, an extremely widespread action on broadleaved and grassy plants. This action encompassed not only herbicidal (i.e., killing) effects, but also--in the case of grass species--predominantly a restriction in growth (i.e., reduced growth height).

In these experiments, compound no. 31 also exhibited, on postemergence application in the greenhouse, a much better herbicidal action than comparative agent B.

On pre- and postemergence application in the greenhouse, active ingredients nos. 23, 3, 6, 30 and 1 exhibited a good herbicidal action.

In further greenhouse experiments, compounds nos. 41, 39 and 36, applied postemergence at a rate of 0.5 kg/ha, had an action at first strongly inhibiting and then increasingly herbicidal, on both broadleaved and grassy plants.

The growth- and bioregulating properties of the active ingredients may be illustrated in a further greenhouse experiment with cotton. In this perennial crop, it is a disadvantage for vegetative and generative growth not to be complete at the end of the first season (i.e., within 1 year). It is also a drawback if defoliated cotton plants ready for harvesting start to sprout and turn green again. In a model experiment with budding and boll-forming cotton plants, compounds nos. 19, 41 and 36, applied to the foliage at rates of 1.0 and 4.0 kg/ha, were able to prevent, or strongly inhibit, this undesirable further growth.

The active ingredients, or agents containing them, may be used pre- or postemergence, but are preferably applied to the foliage.

If the crop plants do not tolerate the active ingredients, application techniques may be used in which the herbicidal or growth-regulating agents are sprayed from suitable equipment in such a manner that the sensitive parts of the crop plants are not touched, and the agents reach the soil or the unwanted plants growing beneath the crop plants (post-directed, lay-by treatment).

The amount of active ingredient or active acid applied depends on the season and the growth stage of the target plants, and varies from 0.1 to 15 kg/ha and more, the higher rates being particularly suitable for total elimination of vegetation.

To increase the spectrum of action and to achieve synergistic effects, the .alpha.-azolylalkanecarboxamides may be mixed and applied together with numerous representatives of other herbicidal or growth-regulating active ingredient groups. Examples of suitable mixture components are diazines, benzothiadiazinones, 2,6-dinitroanilines, N-phenyl-carbamates, thiolcarbamates, halocarboxylic acids, triazines, amides, ureas, diphenyl ethers, triazinones, uracils, benzo-furan derivatives, cyclohexane-1,3-dione derivatives, etc. A number of active ingredients which, when combined with the new compounds, give mixtures useful for widely varying applications are given below by way of example: phenyl)-3(2H)-pyridazinone and salts and salts and salts de 2,2-dioxide 2,2-dioxide ide ide ide N-phenylcarbamate ne ]-dodeca-3,9-diene ulfonate imidazolidin-2-one-1-carboxylic acid isobutylamide dichloride (salts) e-1,3-dione (salts) l ether en-1-one (salts) -en-1-one (salts) l)-3-(2H)-pyridazinone yl-1,3,5-triazin-2-yl-aminocarbonyl]-2-chlorobenzene sulfonamide ______________________________________ List of plant names Botanical name Abbreviation in table Common name ______________________________________ Abutilon theophrasti Abutilon theoph. velvet leaf Avena fatua   --            wild oats Chenopodium album Cheno. alb.    lambsquarters Chrysanthemum spp. Chrys. spp.    marigold spp. Datura stramonium Datura str.    jimsonweed Echinochloa crus galli Echinochl. c.g. barnyardgrass Hordeum vulgare Hord. vulg.    barley Lamium spp.  Lamium spp.    dead-nettle Lolium multiflorum Lolium mult.   annual ryegrass Mercurialis annua Mercur. annua  annual mercury Poa spp.      --            bluegrass Polygonium persicaria Polyg. pers.   ladysthumb, redshank Sesbania exaltata Sesbania exalt. hemp sesbania (coffeeweed) Sinapis alba Sinapis alb.   white mustard Sorghum halepense Sorgh. halep.  johnsongrass Xanthium spp. --            cocklebur ______________________________________

## Claims

1. A process for combating unwanted plants, wherein the plants, seed or the soil are treated with a herbicidally effective amount of a compound of the formula ##STR37## where Ar denotes unsubstituted phenyl, dichlorophenyl, trichlorophenyl, dimethychlorophenyl or trifluoromethylphenyl, R.sup.1 denotes hydrogen or methyl, R.sup.2 denotes hydrogen or C.sub.1 -C.sub.10 -alkyl, R.sup.3 denotes C.sub.1 -C.sub.10 -alkyl, cyclopropyl, cyclohexyl, cyclopropylmethyl, allyl, methallyl, crotyl, 2-methylbut-2-en-1-yl, 2-methylbut-1-en-3-yl, hex-5-en-1-yl, 2-methylbut-1-en-4-yl; propargyl, but-1-yn-3-yl, but-2-yn-1-yl, 3-methylbut-1-yn-3-yl, unsubstituted or halogen-substituted benzyl and .alpha.-phenylethyl, and Az denotes unsubstituted or halogen- or methyl-substituted triazole, or a metal complex thereof.

2. The process of claim 1, wherein the compound of the formula I is 2-(3,5-dichlorophenoxy)-2-(1,2,4-triazol-1-yl)-acetic acid-N-tert-butylamide or 2-(3,5-dichlorophenoxy)-2-(1,2,4-triazol-1-yl)-acetic acid-N-benzylamide or 2-(3,5-dimethylphenyl)-2-(1,2,4-triazol-1-yl)-acetic acid-N-phenylethylamide.

3. The process of claim 1, wherein A.sub.r, A.sub.z, R.sup.1, R.sup.2 and R.sup.3 of compound I respectively are 3,5-dimethylphenyl, 1,2,4-triazolyl, hydrogen, hydrogen and t.-butyl.