CS247184B2 - Herbicidal agent - Google Patents

Abstract

Composition for suppressing unwanted vegetation based on 2-(2-substituted benzoyl)-1,3-cyclohexanediones of the general formula I, where R is C1-C8alkyl, R1- is hydrogen, C1-C8alkyl or a group of the formula Ra-O-?-, where Ra is C1-C4alkyl, or R and R; together represent an alkylene group with 3 to 6 carbon atoms, R2 is chlorine, bromine, iodine, fluorine or C1-C4alkoxy, R3 and R4 independently represent hydrogen, halogen, dialkyl, C1-C4alkoxy, OCF3, cyano, nitro, C1-C4- -haloalkyl, a group of the formula RbSOn-, where Rb is C1-C4alkyl, C1-C4haloalkyl, phenyl, benzyl, a group of the formula -NR°Re, where Rb and Re independently represent hydrogen or C1-C4alkyl, and n is an integer of 0, 1 or 2, and C1-C4alkylthio, R5 is hydrogen or C1-C6alkyl, R6 is hydrogen or. C1-C6alkyl, R7 is hydrogen or C1-C6alkyl, and R8 is hydrogen or C1-C6alkyl, or R and R6 together form a substituted or unsubstituted alkylene ring of 2 to 5 carbon atoms, wherein the substituent is one or two methyl groups, and/or agrochemically acceptable salts thereof.

Description

The invention relates to a means for suppressing unwanted vegetation.

Compounds of structural formula

where

X represents alkyl, n can be 0, 1 or 2 and

Rg represents phenyl or substituted phenyl, are described in Japanese Patent Application Laid-Open No. 84632-1974 as intermediates for the preparation of herbicidal compounds of the formula

where Rg, X and n have the meanings given above and

R ₂ represents alkyl, alkenyl or alkynyl.

Specifically, from the latter group, compounds are mentioned where n is 2, X is 5,5-dimethyl, Rg is allyl and Rg is phenyl, 4-chlorophenyl or 4-methoxyphenyl. The intermediate precursors of these three specifically mentioned compounds have no or almost no herbicidal activity.

In contrast, the compounds of the invention have exceptional herbicidal activity resulting from the substitution of the 2-position of the phenyl group with chlorine, bromine, iodine or alkoxy. The preferred substituent is chlorine. The exact reason why such substitution confers exceptional herbicidal activity on the compound is not fully understood.

The subject of the invention is a composition for suppressing unwanted vegetation based on new herbicidal 2-(2-substituted benzoyl)-cyclohexane-1,3-diones. The compounds according to the invention have the structural formula

where .is C6-C14alkyl, preferably C6-C14alkyl, more preferably methyl, is hydrogen or C6-C14alkyl, preferably C6-C14alkyl, more preferably methyl, or a group of the formula

O

R ^a -O-C where R ^a is C 1 -C 4 alkyl, .i ho P a p . i o together form an alkylene of 3 to 6 carbon atoms,, not j preferably j l j c P ^l .. ,

R ³ is chlorine, bromine, iodine, fluorine or C 1-C 4 alkoxy, preferably methoxy, most preferably R ³ is chlorine, bromine or methoxy,

R ³ and R ⁴ independently represent hydrogen, halogen, preferably fluorine, chlorine or bromine, a C^-C^alkoxy group, preferably methoxy, an OCF^ group, a cyano group, a nitro group, a C^-C^haloalkyl, preferably trifluoromethyl, a group of the formula R^SOn-, where r' ³ is C1-C _^ alkyl, preferably methyl, a C^-C^haloalkyl, phenyl, benzyl, a group of the formula -NR^R ⁶ , where R^ and R ^e independently represent hydrogen or C^-C^alkyl, and n is an integer 0, 1 or 2, preferably 2, and a C^-C^alkylthio group, c £ 7 o

R, R, R and R are independently the same or different and are selected from the group consisting of hydrogen, C1-C6alkyl, preferably _C1 - _C4alkyl , more preferably methyl, most preferably hydrogen or methyl, and salts thereof, with the proviso that ^R5 and ^R6 together may form an unsubstituted or substituted alkylene ring of 2 to 5 carbon atoms, with the preferred substituent being 1 or 2 methyl groups.

4

More preferably, R is chlorine, hydrogen, methyl, alkylthio or methoxy. More preferably, R is hydrogen, chlorine, nitro, CF3 or _R3SO4 , where C1-C4 alkyl, preferably methyl, and n is an integer of 0, 1 or 2, preferably 2.

The compounds of the invention may have the following four structural formulas due to tautomerism:

where R, R

8

R and R have the meanings given above.

The proton, marked by a ring in all tautomers, is relatively labile. These protons have an acidic character and can be removed by any base to form a salt whose anion has the following four resonance forms:

where R, r!, R^, r\ R^, R^, R®, R? and R® have the meanings given above.

Examples of cations of these bases are inorganic cations such as alkali metals, for example lithium, sodium and potassium, alkaline earth metals, for example barium, magnesium, calcium and strontium, or organic cations such as substituted ammonium, sulfonium or phosphonium groups, where the substituent is an aliphatic or aromatic group.

The term aliphatic group is used herein in a broad sense, covering a large group of organic groups characterized by being derived from a) acyclic (open-chain) compounds of the paraffinic, olefinic and acetylenic series of hydrocarbons and their derivatives or b) alicyclic compounds. An aliphatic group may have 1 to 10 carbon atoms.

The term aromatic group is used herein in a broad sense to distinguish it from an aliphatic group and includes a group derived from a) compounds with 6 to 20 carbon atoms which are characterized by the presence of at least one benzene ring and include monocyclic, bicyclic and polycyclic hydrocarbons and their derivatives and b) heterocyclic compounds with 5 to 19 carbon atoms which have a similar structure and are characterized by an unsaturated ring structure containing at least one atom other than carbon, for example nitrogen, sulfur and oxygen, and derivatives of these heterocyclic compounds.

In the above description of the compounds of the invention, alkyl and alkoxy groups include both straight and branched configurations, for example methyl, ethyl, n-propyl, isopropyl, n-butyl, sec-butyl, isobutyl and tert-butyl.

The compounds of the invention and their salts are active herbicides of the general type. That is, they are herbicidally active against a wide range of plant species. The suppression of unwanted vegetation is carried out by applying a herbicidally effective amount of the compounds of the invention to a given area.

The compounds of the invention can be prepared by the following general method:

Typically, molar amounts of the dione and the substituted benzoyl cyanide are used together with a slight molar excess of zinc chloride. The two reaction components and the zinc chloride are contacted in a solvent such as methylene chloride. A slight molar excess of triethylamine is slowly added to the reaction mixture with cooling. The mixture is stirred for 5 h at room temperature. The reaction product is worked up in a conventional manner.

The above substituted benzoyl cyanide can be prepared according to the teachings of T. S. Oakwood and C. A. Weisberger, Organic Synthesis Collected, Vol. III, p. 122 (1955).

The following example describes the preparation of a representative compound of the invention.

Example

4,4-dimethyl-2-(2,4-dichlorobenzyl)-cyclohexane-1,3-dione

CHq , ^ch 3 \ //Ρ o V ¹

Cl

4,4-Dimethyl-1,3-cyclohexanedione (14.0 g, 0.1 mol), 20.0 g (0.1 mol) of 2,4-dichlorobenzoyl cyanide and 13.6 g (0.11 mol) of anhydrous powdered zinc chloride are combined in 100 ml of methylene chloride. Triethylamine (10.1 g, 0.12 mol) is added slowly with cooling.

The reaction mixture was stirred at room temperature for 5 h and then poured into 2N hydrochloric acid. The aqueous phase was removed and the organic phase was washed four times with 150 ml of 5% sodium carbonate Na2CO3.

The aqueous washings were combined and acidified with hydrochloric acid, extracted with methylene chloride, dried and concentrated to give 25.3 g of crude product. The crude product was chromatographed (2% AcOH/Cl^C^) in 5 g aliquots and then concentrated on a rotary evaporator under separator pressure at 50 °C for 30 min to remove AcOH. An oil was obtained (40% yield). The structure was confirmed by instrumental analysis.

The following is a table of certain selected compounds that can be prepared by the process. Each compound is designated by a number which is then used throughout the rest of the text described above.

Table

Merger number

melting point

O

1 II c ₂ h ₅ -oc- 0 II H Cl H 4-Cl H H H H oil 2 _C2H5 - _OC- ^CH 3 Cl H 4-Cl H H H H oil 3 triethanolammonium salt compounds No. 2 oil

continuation of table I

Melting point number

comb. R R ¹ R ² R ³ R ⁴ R ⁵ R ⁶ R ⁷ R ⁸ (°C) 4 triethanolammonium salt compounds No. 7 oil 5 0 CjHj-O-Í- ^CH 3 Cl 3-Cl 4-Cl H H H H oil 6 triethanolammonium salt compounds no. 5 oil 7 ^CH 3 CH ₃ Cl H 4-Cl H H H H oil 8 ch ₃ ch ₃ Cl H 4-Cl CH ₃ H H H oil 9 ch ₃ n-CjH? Cl H 4-Cl H H H H oil 13 ch ₃ H Cl H 4-Cl H H H H oil 14 CH ₃ H Cl H 4-Cl CH ₃ H H H oil 21 ~ ^C 5 ^H 10™ Cl H 4-Cl H H H H oil 22 - ^C 5 ^H 10 - Cl H 4-Cl CH ₃ H H H oil 23 ch ₃ CH ₃ Cl 3-Cl 4-Cl H H H H oil 24 ch ₃ ^Goal 3 Cl 3-Cl 4-Cl CII ₃ H H H oil 35 ' ^iC 3 ^H 7 H Cl 3-Cl 4-Cl H H H H oil 39 ch ₃ ^CH 3 Cl H ₄ - _CH3SO2 H H H H oil 40 ch ₃ ch ₃ Cl H ₄ - _CH3SO2 CH ₃ H H H oil 45 ch ₃ H Cl H ₄ - _CH3SO2 H H H H 48-56 55 ch ₃ CH ₃ Cl 3-Cl ₄ - _CH3SO3 H H H H oil 71 ch ₃ ch ₃ Cl 3-Cl _{4 - C2H5SO2} H H H H 127-129 87 ch ₃ ch ₃ Cl H 4-C ₂ ^h 5S° ₂ H H H H 47-50 88 ^CH 3 ch ₃ Cl H . 4-C ₂ ^h 5S ^O 2 CH ₃ H H H oil 135 CH ₃ ch ₃ Cl 3-OCHj ₄ - _CH3SO2- H H H H oil 167 ^CH 3 ^CH 3 Cl 3-CH ₃ 4-Cl H H H H oil 183 ch ₃ CHj Cl 3-OCH ₃ 4-Cl H H H H oil 199 ch ₃ ^{C2H5 ​} Cl H 4-Cl H H H H oil 200 CH ₃ ^GOAL 3 Cl H H H H H H oil

continuation of table I

Melting point number

comb. R R ¹ R ² R ³ R ⁴ R ⁵ R ⁶ R ⁷ R ⁸ (°C) 201 ^CH 3 ^CH 3 Cl 3-OC ₂ H ₅ Br H H H H 88-93 202 ch ₃ ^CH 3 Cl I 4-Br H H H H 58-69 203 ^CH 3 ^{C2H5 ​} Cl 3-Cl 4-C1 H H H H oil 204 n-C-jH? H Cl H 4-Cl H H H H oil 205 0 II ^c 2 ^h 5° ^c - nC ₃ H ₇ Cl H 4-Cl H H H H oil 206 ch ₃ ^CH 3 Cl H 4-iC,H ₇ SO ₂ H H H H oil 207 ch ₃ ch ₃ Cl 4-iC ₃ H _? O 4-Br H H H H oil 208 ^CH 3 ^CH 3 Cl H 6-F H H H H oil 209 í- ^c 3h ₇ H Cl 3-Cl 4-Cl H H H H oil 210 ^CH 3 ^CH 3 Cl 3-OC ₂ H ₅ 4-Br H H H H oil 211 í-C ₃ H ₇ OC(O) H Cl H 4-Cl H H H H oil 212 C ₂ H ₅ OC(O|- ^nC 3 ^H 7 Cl H 4-Cl I H H H oil 213 - ^C 5 ^H 10 - Cl H 4-Cl H H H H oil 214 ^CH 3 ^CH 3 Cl H 4-Cl H The ^CH 3 H oil 215 ^CH 3 ^Cri 3 Cl H 4-nC ₃ H ₇ Sat ₂ - H H H H oil 216 ^Goal 3 ch ₃ Cl 3-Cl 4-nC ₇ H ₇ SO ₂ - H H H H oil 217 ^CH 3 ^CH 3 ^CH 3° 3-CH ₃ O H H H H H 54-60 218 ch ₃ ch _{3 CH3O} H 4-Cl H H H H oil 219 CH ₃ ^CH 3 Cl H 4-Br c» ₃ H H H oil 220 ^CH 3 ^CH 3 Br H H H H H H oil 221 ^CH 3 ^CH 3 I H H H H H H oil 222 ^CH 3 ^CH 3 P H H H H H H oil 223 ^CH 3 ^CH 3 ch ₃ o H H H H H H oil 224 CH ₃ ch ₃ Cl 3-allyloxy 4-Br H H H H oil

continuation of table I melting point number

comb. R R ¹ R ² R ³ R ⁴ R ⁵ R ⁶ R ⁷ R ⁸ <°c> 225 CH ₃ ch ₃ Cl H ₄ - _CH3SO2 H H ck ₃ H oil 226 ch ₃ ch ₃ Cl 3-CH2O 4-Br CH ₃ H H H oil 227 ^Goal 3 ^CH 3 Br H 3-CN H H H H 128-134 228 ^CH 3 ch ₃ Cl H 4N(CH ₃ )SO 2 ^CF 3 H H H H oil 229 ^CH 3 ^CH 3 Cl 3-NO ₂ H H H H H oil 230 ch ₃ ch ₃ ^{C2H5 °} H 4-C1 H H H H oil 231 ch ₃ ch ₃ Cl H 4- -butylsulfinyl H H H H oil 232 ^Goal 3 ch ₃ Cl 3 _{- C2H5O 4} - _CH3SO2 H H H H 45-52 233 ^CH 3 ch ₃ Cl 3-CH ₃ O ^{4 - C2H5SO2 ​} H H H H oil 234 ch ₃ ch ₃ Cl H 4-nC ₄ H _g SO ₂ H H H H oil 235 ^Goal 3 ^CH 3 Cl 3-Cl 4-nC ₄ H ₉ SO ₂ ch ₃ H H H oil 236 ch ₃ CH ₃ Cl 3-Cl ^{4 - C2H5SO2 CH} 3 H H H oil 237 CH ₃ ^Goal 3 Cl H 4-F H H H H oil 238 CH ₃ H Cl 3-CH ₃ O 4-Br H H H H oil 239 ^CH 3 CH ₃ Cl 3-CH ₃ O H H H H H oil 240 _C h ₃ ch ₃ Cl EtS PrSO ₂ H H H H oil 241 ch ₃ ^CH 3 Cl EtS EtS H H H H oil 242 ch ₃ ^CH 3 Cl EtS EtSO ₂ H H H H oil 243 ^CH 3 ^CH 3 Cl EtS MeSO ₂ H H H H oil

Herbicidal efficacy tests:

As stated, the disclosed compounds, prepared as described above, are phytotoxic and are useful and effective in controlling various plant species. Selected compounds of the invention were tested for herbicidal activity in the following manner.

Pre-emergence herbicide test. The day before treatment, seeds of eight weed species are sown in individual rows in loamy sandy soil, with one row across the width of the plot consisting of one species.

Seeds of green foxtail (Setaria viridis, FT), common horsetail (Echinochloa crusgalli, WG), wild oats (Avena fatua, WO), Ipomoea lacunosa (AMG), Abutilon theophrasti (VL), Brassica juncea (MD), bent grass (Amaranthus retroflexus, PW) or Rumex crispus (CD) and Cyperus esculentus, (YNG) are sewn.

Sufficient seeds are sown so that after emergence there are about 20 to 40 seedlings in each row, depending on the size of the plants.

Using an analytical balance, weigh 600 mg of the compound under investigation onto a piece of parchment tracing paper. The paper with the compound is placed in a 60 ml clear wide-necked bottle and dissolved in 45 ml of acetone or an alternative solvent.

ml of this solution is transferred to a 60 ml clear wide-necked bottle and diluted with 22 ml of a mixture of water and acetone (19:1), containing sufficient polyoxyethylene sorbxtan monolaurate as an emulsifier to produce a final solution with a concentration of 0.5% by volume.

The solution is then sprayed onto the seeded area using a linear spray table calibrated to spray 748 l/ha. 4.48 kg/ha is applied.

After treatment, the plants are placed in a greenhouse at 21.1-26.7°C and irrigated by spray. Two weeks after treatment, the degree of damage or suppression is determined by comparison with untreated control plants of the same age.

For each species, the range of damage is recorded from 0 to 100%, with 0% representing no damage and 100% representing complete suppression.

The test results are shown in Table II.

Table II

Pre-emergence herbicide efficacy of application 4.48 kg/ha

compounds FT WG WO AMG VL MD CDs PW YNG 1 0 85 10 75 100 80 80 75 2 90 90 80 10 90 90 - 80 3 4 100 100 80 60 100 80 90 100 5 80 100 20 40 100 100 80 100 6 40 100 0 40 100 100 80 100 7 100 100 100 80 100 100 90 100 8 100 100 60 45 60 60 80 100 9 60 100 90 20 60 60 60 100 13 100 100 40 5 80 60 80 100 14 80 90 60 95 90 90 100 80 21 25 95 10 20 20 20 60 40 23 100 100 90 90 100 100 100 100 35 100 60 50 80 90 90 40 60 39 60 60 80 80 90 90 60 65 40 100 100 100 100 100 100 100 97 45 100 100 85 100 100 100 90 95 55 100 80 85 100 100 90 100 70 71 90 65 90 85 70 60 100 40 88 40 70 40 40 40 60 70 50 183 64 70 80 40 90 80 70 80

continuation of table XI

compounds FT WG who AMG VL MD CDs PW YNG 199 20 95 60 5 100 100 90 100 200 100 100 80 20 90 40 80 100 201 100 100 70 20 100 100 100 100 202 100 100 80 60 100 100 80 100 203 100 100 0 10 100 100 100 100 204 90 70 10 0 0 0 80 10 205 0 10 0 0 10 10 0 0 206 100 100 90 80 100 100 90 100 207 100 100 90 40 80 90 90 90 208 100 100 85 0 95 85 95 90 209 90 90 50 20 100 100 100 80 211 90 80 25 30 30 45 50 90 212 0 10 0 0 10 10 0 0 213 0 20 0 0 10 20 10 0 214 100 100 90 45 100 100 65 100 215 80 90 95 95 100 100 100 5 216 100 95 95 95 40 100 100 30 217 30 65 0 30 45 40 65 50 218 70 75 0 65 100 50 50 70 219 100 100 100 98 100 100 100 85 220 100 100 85 15 100 100 85 95 221 100 100 65 0 100 100 50 50 222 80 80 55 0 98 55 80 65 223 95 95 10 0 65 0 25 60 224 100 100 100 100 100 100 100 50 225 100 100 75 100 100 100 100 50 226 100 100 60 15 100 100 100 80 227 100 100 55 15 100 100 90 95 228 100 100 60 20 95 100 90 10 229 5 10 0 0 40 20 0 0 230 10 40 10 10 95 40 100 80 231 100 100 75 80 100 100 100 75 232 100 100 90 100 100 100 85 - 233 100 100 80 100 100 100 100 - 234 95 100 50 95 100 100 85 - 235 100 100 70 100 90 100 100 - 236 100 100 75 100 100 100 85 - 237 100 100 55 40 100 100 90 7 238 100 100 65 95 100 100 100 95 239 100 100 30 15 100 100 95 90

- - the species did not germinate for some reason, the blank area indicates an unexamined weed

Post-emergence Herbicide Test. The test is conducted in the same manner as the pre-emergence herbicide test, except that seeds of eight weed species are sown 1012 days prior to treatment. Irrigation of the treated areas is limited to the soil surface, not to the leaves of the emerging plants.

The results of the post-emergence herbicide test are shown in Table III.

Table III

Post-emergence herbicide efficacy of application 4.48 kg/ha

compounds FT WG who AMG VL MD CDs PW YNG 1 85 95 20 95 100 100 95 95 2 90 100 65 100 100 100 100 100 4 60 60 90 40 60 60 90 70 5 40 60 10 20 40 40 90 80 6 40 50 10 60 20 20 60 50 7 80 80 80 60 60 90 60 60 8 100 80 60 30 80 80 80 80 9 70 70 60 40 60 60 60 70 13 40 40 60 30 60 60 90 60 14 100 100 90 10 20 20 90 100 21 0 20 0 0 10 20 10 0 23 100 100 95 70 60 60 80 100 35 90 90 50 20 100 100 100 80 39 100 100 95 100 100 100 90 100 40 100 70 90 100 - 90 98 70 45 100 85 100 85 - 100 100 65 55 100 100 95 100 100 100 100 95 71 100 100 85 100 100 100 100 90 88 100 100 80 100 100 100 100 90 167 100 100 75 80 100 100 100 90 183 100 100 65 30 100 100 100 90 199 100 80 60 20 90 90 80 45 200 90 60 60 60 60 60 40 70 201 90 70 70 40 70 70' 60 60 202 100 90 70 50 100 100 80 80 203 100 100 10 20 20 20 80 60 204 50 30 10 0 0 0 60 0 205 20 40 10 60 90 40 60 40 206 80 80 80 80 100 100 80 50 207 60 50 50 20 60 60 80 60 208 100 80 80 75 - 100 100 95 209 100 60 50 80 90 90 40 60 211 15 100 0 50 100 80 70 40 212 20 40 10 60 90 90 60 40 213 25 45 10 20 20 20 60 45 214 90 80 80 100 100 100 100 70 215 100 100 90 100 100 100 100 90 216 100 100 85 100 100 100 100 95 217 65 100 0 0 100 ' 20 20 90 218 100 100 0 20 100 100 98 95 219 100 100 90 85 100 100 100 95 220 100 65 80 50 100 100 60 60 221 60 70 70 40 80 70 30 50 222 0 60 40 60 100 90 20 30 223 100 75 80 40 100 50 20 30 224 90 100 100 100 100 100 100 40 225 60 70 70 70 - 90 65 40 60

continuation of table II

compounds FT WG WO AMG VL MD CDs PW YNG 226 100 100 85 100 100 100 100 60 227 95 85 90 100 100 100 90 45 228 85 100 0 10 15 95 40 50 229 85 70 65 0 0 0 0 35 230 20 40 10 15 70 40 35 40 231 100 95 100 95 100 95 100 40 232 65 75 75 80 90 85 80 60 233 80 80 70 95 80 85 80 50 234 100 80 25 80 75 80 75 35 235 100 100 40 95 95 100 95 50 236 75 70 50 90 90 100 90 50 237 100 80 80 60 85 60 0 - 238 98 90 60 35 - 100 60 90 239 70 65 20 15 95 40 70 45

Pre-emergence broad-spectrum herbicide test. Several compounds are tested for pre-emergence efficacy against a number of weed species at 2.24 kg/ha:

The procedure is generally similar to the pre-emergence test described above, but only 300 mg of the test compound is weighed and 374 l/ha is applied.

The test omitted the bent dock (PW) and Rumex cerispus (CD) and added the following species:

grasses: roof broom (Bromus teotorum) (DB) multiflorous ryegrass (Lolium multiflorum) (ARG)

Sorghum bicolor (SHC)

Sesbania exaltata (SESB) eggplant (Solanum) (SP) beetroot (Xanthium) (CB)

The test results are shown in Table IV.

Table IV

Preemergence broad-spectrum herbicide test

C. sl. DB FT AFG WG SHC WO BSG AMG SESB VL SP MD YNS CB 24 80 100 100 100 100 80 95 70 60 100 40 85 100 10 210 100 ioo 100 100 100 100 100 20 10 100 20 95 100 20

The compounds of the invention are suitable as herbicides, especially pre-emergence herbicides, and can be applied by various methods at various concentrations. In practice, the compounds described are formulated into herbicidal compositions by mixing with a herbicidally effective amount the accompanying substances and carriers commonly used to facilitate the dispersion of active ingredients for agricultural purposes, taking into account the fact that the formulation and method of application of the toxic substance may affect the effectiveness of the substances in a given application.

Thus, these effective herbicidal compounds may be formulated as granules of relatively large particle size, as wettable powders, as emulsifiable concentrates, as dusts, as solutions, or as any of the other known types of formulations depending on the desired method of application.

For pre-emergence herbicidal application, preferred formulations are wettable powders, emulsifiable concentrates, and granules. These formulations may contain from as little as about 0.5 to about 95% by weight or more of the active ingredient.

The herbicidally effective amount depends on the nature of the seeds or plants being controlled and the application rate ranges from about 0.06 to about 28 kg/ha, preferably from about 0.11 to about 11.2 kg/ha.

Wettable powders are in the form of finely divided particles that disperse readily in water or other dispersion media. The final application of the wettable powder to the soil is either in the form of a dry powder or in the form of a dispersion in water or other liquid.

Carriers for wettable powders include, for example, talc, kaolin clays, silicas, and other readily wettable organic or inorganic thickeners. Wettable powders are commonly prepared to contain from about 5 to about 95% of the active ingredient and usually also contain a small amount of a wetting, dispersing, or emulsifying agent to facilitate wetting and dispersion.

Emulsifiable concentrates are homogeneous liquid compositions that are dispersible in water or other dispersion media, and may consist entirely of the active compound and a liquid or solid emulsifier, or may further contain a liquid carrier, for example xylene, heavy aromatic naphthas, isophorone and other non-volatile organic solvents.

For herbicidal application, these concentrates are dispersed in water or other liquid carrier and are usually applied to the area to be treated by spraying. The weight percentage of the necessary active ingredient may vary depending on the manner in which the composition is to be applied, but generally amounts to about 0.5 to 95% by weight of the active ingredient in the herbicidal composition.

Granular compositions, where the toxicant is carried on relatively coarse particles, are usually applied undiluted to the area where vegetation control is desired. Carriers for granular compositions include sand, millstone, bentonite clays, vermiculite, perlite, and other organic or inorganic materials that absorb or can be coated with the toxicant.

Granular compositions are typically prepared to contain about 5 to about 25% of the active ingredient, which may include surfactants such as heavy aromatic naphthas, kerosene or other petroleum fractions or vegetable oils, and/or tackifiers such as dextrins, glues or synthetic resins.

As wetting, dispersing or emulsifying agents, for example, alkyl and alkylaryl sulfonates and sulfates and their sodium salts, polyfunctional alcohols and other types of surfactants, many of which are commercially available, are used in agrochemical formulations. The surfactant usually constitutes 0.1 to 15% by weight of the herbicidal composition.

Dusts, which are free-flowing mixtures of the active ingredient with finely divided solids such as talc, clays, flours or other organic and inorganic solids that act as dispersants and carriers of the toxicant, are suitable formulations for incorporation into soil.

Pastes, which are homogeneous suspensions of finely divided solid toxicant in a liquid carrier such as water or oil, are used for special purposes. These formulations usually contain about 5 to about 10% by weight of the active ingredient and may also contain a small amount of a wetting, dispersing or emulsifying agent to facilitate dispersion. For application, pastes are usually applied to the area to be treated by spraying.

Other suitable formulations for herbicidal application include simple solutions of the active ingredient in a dispersant in which it is completely soluble at the desired concentration, for example in acetone, alkylated naphthalenes, xylene and other organic solvents.

It is also possible to use pressurized sprays, for example aerosols, where the active ingredient is dispersed in finely divided form as a result of the evaporation of a low-boiling carrier solvent, such as freons.

The phytotoxic compositions of the present invention are applied to plants in a conventional manner. Powder and liquid compositions can be applied to plants using machine sprayers, frame and hand sprayers, and spray nozzles.

The compositions can also be applied from an aircraft in powder or spray form, since they are effective at very low rates. For example, to modify or limit the growth of germinating seeds or emerging seedlings, the powder and liquid compositions are applied to the soil by conventional methods and distributed in the soil to a depth of at least 1.27 cm below the soil surface.

It is not necessary for the phytotoxic compositions to be mixed with the soil particles, as these compositions can also be applied by simply spraying or watering the soil surface. The phytotoxic compositions of the present invention can also be added to the irrigation water supplied to the treated plot.

This method of application allows the compositions to penetrate the soil along with water absorption. Powder compositions, granular compositions or liquid formulations applied to the soil surface can be distributed below the soil surface by conventional methods such as disking, shearing or mixing.

The phytotoxic compositions of the present invention may further comprise other additives, for example fertilizers and other herbicides, pesticides, etc., used as adjuncts or in combination with any of the adjuncts described above.

Other phytotoxic compounds useful in combination with the compounds described above include, for example, anilides such as 2-benzothiazol-2-yloxy-N-methylacetanilide, 2-chloro-2',6-dimethyl-N-(n-propylethyl)acetanilide, 2-chloro-2',6'-diethyl-N-(butoxymethyl)acetanilide,

2,4-dichlorophenoxyacetic acids, 2,4,5-trichlorophenoxyacetic acid, 2-methyl-4-chlorophenoxyacetic acid and their salts, esters and amides, triazine derivatives such as 2,4-bis(3-methoxypropylamino)-6-methylthio-s-triazine, 2-chloro-4-ethylamino-6-isopropylamino-s-triazine and

2-ethylamino-4-isopropylamino-6-methylmercapto-s-triazine, urea derivatives such as 3-(3,5-dichlorophenyl)-1,1-dimethylurea and 3-(p-chlorophenyl)-1,1-dimethylurea, and acetamides such as N,N-diallyl-alpha-chloroacetamide and the like, benzoic acids such as 3-amino-2,5-dichlorobenzoic acid, thiocarbamates such as S-(1,1-dimethylbenzyl)-piperidine-1-carbothioate,

3-(4-chlorophenyl)methyldiethylcarbothioate, ethyl-1-hexahydro-1,4-azepine-1-carbothioate, S-ethylhexahydro-1H-azepine-1-carbothioate, S-propyl-N,N-dipropylthiocarbamate, S-ethyl-N,N-dipropylthiocarbamate, S-ethylcyclohexylethylthiocarbamate, etc., anilines such as 4-(methylsulfonyl)-2,6-dinitro-N,N-substituted aniline, 4-trifluoromethyl-2,6-dinitro-N,N-di-n-propylaniline, 4-trifluoromethyl-2,6-dinitro-N-ethyl-N-butylaniline, 2-[4-(2,4-dichlorophenoxy)phenoxy]-propanoic acid, 2-[1-(ethoxyiminobutyl]-5-L2-ethylthio)propyl] -3-hydroxy-2-cyclohexen-1-one, (+)-butyl 2-(4-[(5-trifluoromethyl)-2-pyridinyl)oxy]-phenoxy)propanate, sodium 5-[2-chloro-4-(trifluoromethyl)phenoxy^-2-nitrobenzoate, 3-isopropyl-1H, 2,1,3-benzothiadiazine-4(3H)-one-2,2-dioxide, and 4-amino-6-tert.butyl-3(methylthio)-as-triazin-5(4H)-one or 4-amino-6-(1,1-dimethylethyl)-3-(methylthio)-1,2,4-triazin-5(4H)-one and S-(Ο,Ο-diisopropy1)-benzenesulfonamide.

Fertilizers that can be used in combination with active ingredients include ammonium nitrate, urea and superphosphate. Other suitable additives include materials in which plant organisms take root and grow, such as compost, manure, humus, sand, etc.

Claims (6)

1. Herbicidal composition, characterized in that it contains a compound of the general formula I as an active ingredient B® ifi O wherein C1-C8alkyl is hydrogen, C1-C6alkyl or a group of the formula R ^a -O-C where R is C 1 -C 4 alkyl, or R and R ¹ together represent an alkylene group with 3 to 6 carbon atoms, R is chlorine, bromine, iodine, fluorine or C1-C4 alkoxy, R ³ and R ⁴ independently represent hydrogen, halogen, C1-C4 alkyl, C 1 -C 4 alkoxy group, OCF^ group, cyano group, nitro group, C 1 -C 4 haloalkyl group of the formula R ^b SO. where R is C-C-alkyl, C-haloalkyl, phenyl, benzyl, a group of the formula -NR- ^R6 , where R- and ^R6 independently represent hydrogen or C-C-alkyl, and n is an integer of 0, 1 or 2, and a C-C-alkylthio group, R ⁵ is hydrogen or C ₁ -C ₆ alkyl·, R ⁶ is hydrogen or C,-C,alkyl, 1 0 R ⁷ is hydrogen or C^-C^alkyl and R ⁸ is hydrogen or C.-C,alkyl or 1 b ^R5 and together forms substituted carbon atoms, where the substituent is one or two methyl groups, and/or agrochemically acceptable salts thereof. 2. Herbicidal composition according to item 1, characterized in that it contains as an active ingredient a compound of formula I, where R is C1-C4 alkyl, R ¹ is hydrogen or C 2 -C 4 alkyl, R is chlorine, bromine, iodine or methoxy, 3 4 R and R independently represent hydrogen, chlorine, bromine, methyl, methoxy, nitro, CF^ or a group of the formula R ^D SO _n ", where R ^D is C^-C^alkyl and n is the number 2, R ⁵ is hydrogen or C^-C^alkyl R ⁶ is hydrogen or C^-C^alkyl R ⁷ is hydrogen and R ⁸ is hydrogen. 3. Herbicidal composition according to item 1, characterized in that it contains as an active ingredient a compound of formula I, where R is methyl, R ¹ is hydrogen or methyl, R is chlorine, bromine, iodine or methoxy, 3 4 R and R independently represent hydrogen, chlorine, bromine, methyl, methoxy, nitro, CF2O3 or a group of formula R2SO2-, where C1-C4 alkyl and n is 2, R ⁵ is hydrogen or methyl R ⁶ is hydrogen or methyl R ⁷ is hydrogen and R ⁸ is hydrogen. 4. Herbicidal composition according to item 1, characterized in that as an active ingredient 1 2 3 contains a compound of formula I, where R is methyl, R is methyl, R is chloro, R is hydrogen, R is 4-chloro, R ⁵ is hydrogen, R 6 is hydrogen, R 7 is hydrogen and R 8 is hydrogen. 5. Herbicidal composition according to item 4, characterized in that as an active ingredient 1 2 3 contains a compound of formula I, wherein R is methyl, R is methyl, R is, chlorine, R is hydrogen, R ⁴ is 4-chloro, R ^D is hydrogen, R* ⁵ is hydrogen, R is hydrogen and R is hydrogen, in the form of the triethanolammonium salt. 6. Herbicidal composition according to item 1, characterized in that it contains as an active ingredient a compound of formula I, where R is methyl, R ¹ is methyl, if is chlorine, is hydrogen, is 4-CH3SO2-, is hydrogen, R^ is hydrogen, R ⁷ is hydrogen.1 R ^K is hydrogen.