JPS6029681B2 - Weed control composition containing pyrazolium salt - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a herbicidal composition containing a pyrazolium compound having the structure of formula 1 below as an active ingredient.

In (this), R and R2 are each a methyl group; R3 and R4 are a cycloalkyl group C3-C6, an alkyl group C2-C, .
and a group selected from silk consisting of groups, and X is 1, CH3S04 or C
represents I04, m is an integer equal to the valence of the anion, and n is 1 or 0.

However, when n=0, the group is limited to only one of R3 and R4.

) The present invention also relates to a method of controlling undesirable plant species using compounds of formula 1.

R,, R2, R3, R4, m and x are the following formula 1 as above
The diketone precursor used in the preparation of the pyrazo IJum salt having the structure is dimethyl sulfoxide (
It is prepared by reacting methyl ketone 0 with an alkyl carboxylic acid ester, preferably methyl or ethyl ester, using a neutral solvent such as DMSO), dimethylformamide (DMF), xylene-toluene, benzene, etc.

This reaction is carried out at a temperature of between 0.000 and 40°C, most preferably between 0.000 and 0.000
It is desirable to carry out at ~25 qo. This reaction yields an 8-diketone corresponding to the reactant used. The methyl ketone and carboxylic acid ester are reacted in equimolar amounts, but it is generally desirable to use a slight excess of carboxylic acid ester in the reaction mixture, ie, up to about 10% excess. This reaction can be explained as follows. (R3 and R4 in the formula are as described above.

) To prepare a compound of formula 1, a diketone of formula W is first condensed with hydrazine or an alkylhydrazine to form the corresponding 3,5-di-substituted pyrazole, which is alkylated to form the desired pyrazolium salt of formula 1. to form.
These reactions can be schematically explained as follows. (
In this), R is a methyl group, and R,, R2, R3, R4, m and X are as described above.

The symbol } indicates that the R substituent is attached to either position. ) Diketones and hydrazine react in equimolar amounts.

However, a small excess of either reactant, up to about 10%, may be used advantageously. This reaction is generally carried out in the presence of either a protic or aprotic solvent, and
It is carried out at a temperature of qo to 1500°C, preferably 80qo to 120°C. Preferred solvents for these reactions include protic solvents such as methanol, ethanol, n-propanol, isoprobanol, n-butanol, and lower alcohols including isobutanol. Suitable aprotic solvents for use in this reaction include xyley, toluene,
These include benzene, dimethyl sulfoxide, dimethyl formamide and pyridine. The use of an acid catalyst such as p-toluenesulfonic acid increases the rate of the condensation cyclization reaction and may be used to advantage if the reaction proceeds slowly. Conveniently, when hydrazine is used in the first condensation reaction of the diketone, the alkylation of the pyrazole formed is carried out with a known alkylating agent, preferably an alkali metal hydride, an alkali metal alkoxide or a tertiary organic amine. Accomplished in the presence of acid acceptors.

Preferred acid acceptors include sodium or potassium hydroxide, sodium or potassium methoxide, ethoxide, propoxide or t-butoxide, trimethylamine, triethylamine and pyridine. Alkylation of pyrazole in the presence of solvent from 5000 to 200
It is preferable to carry out the process at a temperature of 9,000 to 1,200 degrees. Preferred solvents are aromatic hydrocarbons such as toluene, xyley and chlorobenzene; ketones having 4 to 7 carbon atoms such as methylisobutylketone (MIBK) and methylbutylketone (MBK);
C2-C5 alcohol; dimethyl sulfoxide (DM
dimethylformamide (DMF), acetonitrile, nitrobenzene and N,N-dimethylacetamide; and cyclic ethers such as dioxane and tetrahydrofuran. Examples of alkylating agents include alkyl halides, dialkyl sulfates, alkyl phosphates, alkyl hydrogen sulfates, and alkyl toluenesulfonates, in which each alkyl group has from 1 to 4 carbon atoms.

Preferred alkylating agents include alkyl halides such as methyl, ethyl, n-propyl, isopropyl, n-butyl, isobutyl and t-butyl chlorides and bromides; dialkyl sulfates; alkyl hydrogen sulfates and alkyl toluenesulfonates. Although the 3,5-disubstituted pyrazole is combined with an equimolar amount of the alkylating agent, it is a good practice to use an excess of the alkylating agent.

Preferably, the molar ratio of alkylating agent to pyrazole is within the range of 1:1 to 15:1. When using hydrazine, clearly twice the molar amount of alkylating agent is required. In these alkylation reactions, solid or oily pyrazolium salts are separated when the reaction mixture is cooled and are now purified by separation from the organic layer.

However, in some cases, especially when R3 and R5 are highly lipophilic (e.g., 3,5-dicyclohexyl, 3-cyclohexy-5-phenyl and 3-dodecyl-5-phenyl compounds), the pyrazo 1' Separation of murine salts cannot be easily achieved. In such a case, the product can be obtained by evaporating the solvent, dissolving the residue in chloroform, washing the chloroform layer with water, and then evaporating the chloroform to obtain the pyrazolium salt as a residue. . When using toluene sulfonate or methyl sulfate as alkylating agent, impure or hygroscopic substances are now obtained due to anionic contamination (such as HS04' or S04''). The mixed anions are purified by passing the aqueous solution through an anion exchanger. Alternatively, the mixed anion solution is converted to iodide using a saturated potassium iodide solution or a sodium iodide solution. This latter treatment produces iodide which is relatively insoluble in water.To obtain perchlorate which is insoluble in water, perchlorate is removed by adding a dilute aqueous solution of perchloric acid to an aqueous pyrazolium salt solution. Further, CH3S04-, HS04-, S0
Pure pyrazolium salts such as 4= or C-2 can be converted to new pyrazolium salts such as iodides and perchlorates by anion exchange chromatography methods as described above. Pyrazolium halides can be produced as described above, except that the reaction is carried out in a closed vessel or glass-lined bomb maintained at about 100 q0. Another aspect of the invention involves applying a herbicidally effective amount of a compound of Formula 1 to the leaves of an undesirable plant.

They are used at a rate of about 0.25 to 10.0 pounds per acre, preferably 0.50 to 5.0 pounds per acre. Surprisingly, these compounds are also useful as anti-powdery mildew agents when applied to plant foliage at a rate of about 0.25 to 10.0 pounds per acre.
What is important in the present invention is the group represented by R3,
This is a combination of selected groups represented by R4.

When R3 is a phenyl group, R4 is C2-C, . (preferably C5 to C, .) alkyl group, and R, R2, m and Later on, it can be selectively suppressed very well. This is completely surprising since known lower homologs in which R4 is a methyl group do not have such herbicidal activity at all. Furthermore, both R3 and R4 are phenyl groups, and a pyrazolium salt with R, , R2, m and Although 3,5-diphenylpyrazo-1'um salt is already known as a commercially available product, it has the disadvantage that it does not exhibit any weed-suppressing effect before germination.

In this respect, the compound of the present invention has a remarkable weed-suppressing effect before germination, so it must be said that it also has surprising properties. Furthermore, in terms of the same post-emergence inhibitory effect, the compounds of the present invention are particularly effective against broad-leaved weeds when used in a smaller amount per acre than the 3,5-diphenylpyrazolium salt, which is another advantageous feature. It is. In practice, aqueous concentrates can be applied directly to the leaves of undesirable broadleaf weeds and grasses as liquid sprays. Alternatively, they may be further diluted with water and applied as a dilute aqueous spray to these undesirable plants. Water-mixable concentrates are prepared by dissolving 15% to 95% of the compound in 85% to 5% of the water-miscible solvent. Hydrothermally miscible solvents include water itself, other sacrificial water-miscible solvents such as 2-methoxyshetanol, methanol, propylene glycol, diethylene glycol, diethylene glycol monoethyl ether, formamide and dimethylformamide. Application of the substance may be carried out by placing a quantity of water-miscible concentrate in a spray tank (as is) or in combination with additional water or a suitable diluent such as one of the polar solvents mentioned above. It is done. The behavior of the product in all the abovementioned compositions applied as liquid sprays is unexpectedly improved by the addition of one or a mixture of surfactants. Conventional anionic, ionic and anionic-nonionic surfactants can be used. Examples of nonionic surfactants include:

Alkyl polyoxyethylene ether, polyoxyethylene (20) sorbitan monolaurate, polyoxyethylene (20) sorbitan monooleate, alkylaryl polyglycol ether, alkyl phenol ethoxylate, trimethyl nonyl polyethylene glycol ether, alkyl phenol oxidation Ethylene condensate, octylphenoxypolyethoxyethanol, nonylphenyl polyethylene glycol ether, polyoxyethylene condensate, polyoxypropylene, aliphatic polyether, aliphatic polyester, alkylaryl polyoxyethylene glycol, etc. be. Examples of anionic surfactants include sodium dodecylbenzenesulfonate and dioctyl ester of sodium sulfosuccinate.

Suitable cationic surfactants include dicocodimethylammonium chloride, stearamidopropyldimethyl 6-hydroxyethylammonium nitrate, and the like. In order to moisten the plant leaves well with the mist solution, these surfactants are preferably added to the spray tank in a proportion of 0.1 to 5% by volume.

The surfactant-containing herbicide concentrate contains about 3% by weight of a suitable pyrazolium salt, about 25-50% by weight water, and the balance (25-4% by weight).
5% by weight) of the selected surfactant.

Surfactants that are particularly useful in the preparation of suitable surfactants, including thickeners, include octylphenol oxide ethylene condensates, ethanolic solutions of alkylphenol ethoxylates, ethylene oxides prepared from ethylene oxide and alkylaryl polyglycol ethers, etc. There is a polyglycol ether condensate. Other formulations that may be used to advantage with the compounds of this invention include dusting powders, dusting concentrates, moisturizing powders, and the like.

Spraying agents generally contain from about 1 to 25% by weight of active material.
It is prepared by grinding with 75% by weight of solid diluents such as kaolin, attapulgite, talc, pumice, diatomaceous, fuller's, wood flour, etc.

Concentrated dispersants contain about 25-95% active agent by weight of about 75-5%.
It is prepared in a similar manner except that it is milled with % diluent by weight.

Moisturizing powders are prepared in the same manner as concentrated dusting powders, except that about 1 to 5% by weight of a dispersing agent such as a calcium salt of polymerized alkylaryl sulfonic acid, sodium lignosulfonate or sodium condensed naphthalene sulfonate is added. is mixed into the mixture, and about 1 part of a surfactant such as polyoxyethyleneated vegetable oil, alkylphenoxypolyoxyethylene ethanol, sodium alkylnaphthalene sulfonate is mixed into the mixture.
The difference is that ~5% is further mixed with the components.

In practice, the moisturizing powder is dispersed in water and applied as a liquid spray to the leaves of the unwanted plants. The application rate should be sufficient to provide about 0.25 to 10 pounds/acre of pyrazo IJum salt. and 0.5-5.
Although 0 pounds/acre of the salt is generally sufficient to kill undesirable broadleaf weeds and grasses, it should be recognized that rates as high as 10 to 20 pounds/acre can also be used. Of course, these higher rates are used in areas such as under railway sidings, power lines, and along hedges that separate property lines from fields. To further facilitate understanding of the present invention, the following is provided, first for the purpose of illustrating certain details and specific details of the present invention, and also for the purpose of illustrating the method of manufacturing raw materials useful in the present invention. Reference examples and examples are presented.

All parts and percentages are by weight unless otherwise noted.
Reference example 1 1,3-dicyclohexyl-1,3-f.

Manufacture of sodium hydride (39% at 54%)
．． 5 days, 0.889 mol) was added to the pestle machine, condenser, drying tube,
Place in a suitable flask equipped with a dropping funnel and thermometer and cool to 18° with ice.

Slowly add dimethyl sulfoxide (700 g) dried over 4A molecular sieves.

After the addition is complete, the reaction mixture is concentrated at room temperature for 30 minutes. The ice solution is replaced and a mixture of cyclohexanecarboxylic acid ethyl ester (138.8 hours, 0.889 moles) and cyclohexyl methyl ketone (101.9 hours, 0.80 moles) is added to the bottle. No fever was observed. The reaction mixture becomes lighter in color and some foaming is observed. After the addition is complete, remove the ice cubes and let the reaction mixture stand at room temperature overnight. The cloudy, deep pale yellow reaction mixture is poured onto ice (8 min) containing phosphoric acid (50 min) and extracted with ether. The ether layer is washed with water, dried and vacuum stripped to give a golden oil with a strong ester odor (204). If desired, this product can be purified by reaction with a copper rust salt in a conventional manner. When pure, this has a melting point of 5000 to 52
It is a white crystalline substance having a molecular weight of 0.00. Analysis result calculation value C,
5th 2402, C, 76.22: Sun, 10.24
Experimental value C, 76.20; Date, 10.03 Other B-diketones can be prepared from esters and ketones containing R3 and R, as described above.

Thus 1-cyclopropyl-3-phenyl-1,3-
Propanedione is produced from ethyl benzoate and cyclopropyl methyl ketone in the presence of sodium amide, melting point 36
Produced as a ~370 solid. Furthermore, the melting point is 38-40
It has been found that the same compound of q0 can alternatively be prepared from ethyl cyclopropanecarboxylate, acetophenone and sodium hydride. Furthermore, a series of 1-alkyl-3
-Phenyl-1,3-propanedione was prepared from carboxylic acid ethyl ester and acetophenone in the presence of sodium amide. Practical use is expressed using the following equation. R3 and R4 in the formula are shown in Table 1 below.

Table 1 Using an appropriate carboxylic acid ester and substituted methyl ketone,
Other propanediones that can be produced by the method described above include:

1,3-dicyclohexenyl-1,3-propanedione; 1,3-dicyclobentenyl-1,3-pro/gundione; 1-phenyl-3-n-benzenyl-1,3-pro/gundione; 1-phenyl-3-cycloheptane-1
,3-propanedione; 1-phenyl-3-undecyl-1,3-propanedione; 1,3-dibenzyl-1
, 3-pro/gundione; 1-benzyl-3-cyclohexyl-1,3-pro/gundione; 1-(1-methylcyclohexyl)-3-phenyl-1,3-propanedione; 1-(2-methylcyclohexyl)- 3-phenyl-1,3-propanedione; 1,3-di-t-butyl-1,3-pro/gundione; 1-cyclohexyl-3
1-(m-tolyl)-1,3-propanedione; 1-cyclohexyl-3-(o-fluorophenyl)-1,3-propanedione; 1-(p-chlorophenyl)-1,3-cyclobentyl-1,3-propanedione; -(p-Fromophenyl)-3-cyclohexyl-1,3-propanedione; 1-penzyl-3-(p-methylthiobenzyl)-1,3-pro/f-dione; 1-cyclohexyl-3-(p-cyanophenyl)-1 ,3-propanedione; 1-cyclohexyl-3-(m-trifluoromethylphenyl)-1,3-propanedione: 1-p-anisyl-3-n-hexyl-1,3-propanedione; 1
-cyclohexylmethyl-3-phenyl-1,3-propanedione; 1,3-dicyclopropylmethyl-1,3
-pro/gundione; 1,3-dicyclopropyl-1,
3-propanedione; 1-cyclohexyl-3-ethyl-1,3-propanedione; 1-cyclobentyl-3-
Phenyl-1,3-pro/gundione; 1,3-dicyclohexylmethyl-1,3-propanedione; 1-cyclohexyl-3-(p-methylsulfonylphenyl)-1,3-propanedione; 1-(2-carboxyphenyl) 3-2-sodium salt of 1-3-cyclohexyl-1,3-propanedione;
2-sodium salt of -cyclobentyl-1,3-pro/f-dione; 2-sodium salt of 1-penzyl-3-(2-carboxyphenyl)-1,3-propanedione.

Reference example 23-cyclopropyl-1-methyl-5-phenylpyrazole and 5-cyclopropyl-1-methyl-
Production of 3-phenylpyrazole 1-cyclopropyl-3
- Phenyl-1,3-propanedione (37.6 pm, 0
．． 2 mol) and 2-propanol (250 ml) are heated to reflux point.

Methylhydrazine (10.2 hours, 0.22 mol) is then added dropwise and the solution is refluxed until reaction completion (2.2 hours). The solution is then filtered and vacuum stripped to give a yellow oil (39.2 min, 99%). Testing this product on a silica gel thin layer chromatography dish developed with chloroform and iodine indicates the presence of impurities. Chromatography of the product on silica gel with chloroform gives a white cloudy oil. The isomers may be used as a mixture or after separation by conventional chemical separation methods such as fractional crystallization. Analysis result: Calculated value: C, 3 days, C as 4N2, 77.68: days,
7.26; N, 13.52 experimental value: C, 77.92: day, 7.33; N, 13.561-cyclopropyl-3-
Using a suitable 1,3-propanedione as a substitute for phenyl-1,3-propanedione, a pyrazole having the following structural formula is prepared by the method of this example.

The results of this method are shown in Table 2 below.

The symbol { indicates the optional position of the methyl substituent.
Table 2 Other pyrazoles that can be prepared by the above method using the appropriate 1,3-propanedione include: 3,5-dicyclohexenyl-1-methylpyrazole: 3,5-dibenzyl-1- Methyl pyrazole;
3,5-di-t-butyl-1-methylpyrazole; 3,
5-Dicyclof.

Lopyl-1-methylpyrazole; 3-penzyl-5-cyclohexenyl-1-(and 2)-methylpyrazole; 1-(and 2)-methyl-3-(1-methylcyclohexyl)-5-phenylpyrazole; 1 -(and 2
)-Methyl-3-(2-methylcyclohexyl)-5-
Phenylpyrazole; 3-cyclohexyl-1-(and 2)-methyl-5-(m-tolyl)-pyrazole; 3
-cyclohexyl-5-(o-fluorophenyl)-1
-(and 2)-methylpyrazole; 3-(p-chlorophenyl)-5-cyclobenthyl 1-(and 2)-
Methylpyrazole; 3-(p-furomofenyl)-5-
Cyclohexyl-1-(and 2)-methylpyrazole; 3-penzyl-1-(and 2)-methyl-5-(p
-methylobenzyl) ~ pyrazole; 3,5-(p,p
'-dicyclobenzyl)-1-methylpyrazole; 3-
Cyclohexyl-5-(p-cyanophenyl)-1-(
and 2) -methylpyrazole: 3-cyclohexyl-
1-(and 2)-methyl-5-(m-trifluoromethylphenyl)-pyrazole; 3-(p-anisyl)-
5-n-hexyl-1 (and 2)-methylpyrazole; 3-cyclohexylmethyl-1 (and 2)-methyl-5-phenylpyrazole; 3,5-dicyclohexylmethyl-1-methylpyrazole; 3-cyclohexyl-
5-ethyl-1 (and 2)-methylpyrazole; 3-
It is cyanobentylmethyl-1 (and 2)-methyl-5-phenylpyrazole. Furthermore, when a hydrazine different from methylhydrazine is used, the following is obtained:
3,5-dicyclohexyl-1-ethylpyrazole; 1
-t-butyl-3,5-disic. Hexylpyrazole;
3-(2-carbomethoxyphenyl)-5-cyclohexyl-1(and 2)-methylpyrazole; 3-(2-carbomethoxyphenyl)-5-cyclobenzyl-1(
and 2)-methylpyrazole; 3-(2-carboxyphenyl)-5-cyclohexyl-1(and 2)-methylpyrazole; 3-(2-carboxyphenyl)-5
-cyclobenzyru 1(and 2)-methylpyrazole; 3-penzyru 5-(2-carboxyphenyl)-1
(and 2)-methylpyrazole and 3-(2-rubomethoxyphenyl)-5-cyclohexenyl-1(and 2)-methylpyrazole. Reference Example 3 Production of methyl sulfate of 3-cyclohexyl-1,2-dimethyl-phenylpyrazolium 1-
Methyl-3(5}-cyclohexyl-5(3}-phenylpyrazole (8.0 mL, 0.033 mol) is dissolved in dry toluene and warmed to 6500 ℃.

Dimethyl sulfate (4.5 min, 0.035 mol) is then added and the mixture is brought to reflux. Thin layer chromatography (benzene) after 1.5 hours shows that a small amount of pyrazole remains.

After 2 hours the reaction mixture begins to darken and heating is discontinued.

Upon cooling, a white solid forms which is heated and washed with dry toluene. This sticky white solid is vacuum dried at room temperature to yield a brittle solid. Then add hexane to break up the solids and collect them in the oven. This solid (6.3 min, 50% yield) has a melting point of 4800-51°C. Becomes sticky (hygroscopic) when exposed to air. The analysis results are as follows. Analysis result: Calculated value: C, 8th 26N2S04, day 20 C, 5
6.24; Sun, 7.34; N, 7.29 Experimental value: C, 5
6.91; Sun, 7.33; N, 7.12 Reference example 45-
Preparation of methyl sulfate of cyclopropyl-1,2-dimethyl-3-phenylpyrazolium 3 - Cyclopropyl-1
-Methyl-5-phenylupyrazole and 5-cyclopropyl-1-methyl-3-phenylpyrazole (33.1
A mixture of dry toluene (0.167 mol) and dry toluene (25 mol) was heated to reflux and about 25 mol of water was added to Dean Sta.
Remove using rk trap.

This solution was then cooled and dimethyl sulfate (18',0,1
93 mol) is added. This reaction mixture was diluted to 100 oo
．． Keep for 5 hours. A yellow-brown oil forms which becomes solid upon cooling. When this solid is filtered and vacuum dried, 163
Cream solid with melting point between 0o and 170o (49
．． 5 nights, 91.5%). The analysis results are shown below. Analysis results: Calculated value: C, 5th day, 2nd evening 04 C, 55.54; Sun, 6.22; N, 8.64; S, 9.89 Experimental value: C, 55.27: Sun, 6 .23:N, 9.48
; S, 9.99 According to the method of the above-mentioned Reference Example, the compounds shown in Table 3 below are prepared using a suitable 1-methylpyrazole in place of 3-cyclopropyl-1-methyl-5-phenylpyrazole.

It has the following general formula: Table 3 Other pyrazolium compounds that can be produced by the method of Reference Example 4 include the following.

3-cyclohexyl-1,2-dimethyl-5-(m-tolyl)pyrazoyl methyl sulfate; 3-cyclohexyl-1,2-dimethyl-5-(o-fluorophenyl)
Pyrazolium methyl sulfate; 3-(p-furomophenyl)-5-cyclohexyl-1,2-dimethylpyrazo IJ
3,5-(p,p'-dicoobenzyl)-1,2-dimethylpyrazolium methyl sulfate;
3-Cyclohexyl-1,2-dimethyl-5-(m-trifluoromethylphenyl)pyrazolium methyl sulfate: 3-(p-anisyl)-1,2-dimethyl-5-n-
Hexylpyrazolium methylsulfate; 3-cyclohexyl-1,2-dimethyl-5-ethylpyrazolium methylsulfate; 3,5-dicyclohexyl-1-ethyl-2-methylpyrazolium methylsulfate; 3-(2- 3-(2-carbomethoxyphenyl)-1,2-dimethylpyrazolium methyl sulfate; 3-(2-carbomethoxyphenyl)-1,2-dimethylpyrazolium methyl sulfate.

When reacted with dimethyl sulfate using the method described above, the following pyrazoles yield a product that is a mixture of methyl sulfate and hydrogen sulfate.

In this case, the product is completely converted to iodide and/or perchlorate by dissolving it in water and treating it with saturated potassium (or sodium) iodide or dilute perchloric acid, respectively. . When using undecyl- and cycloheptyl groups, for example with or, the methyl sulfate/hydrogen sulfate does not separate upon cooling the reaction mixture.

In such cases, the reaction mixture is vacuum stripped and the residue is dissolved in water and used for the production of iodide and/or perchlorate without solvent extraction. Reference Example 5 Process for producing 5-cyclopropyl-1,2-dimethyl-3-phenylpyrazolium perchlorate 5-cyclopropyl-1
, 2-dimethyl-3-phenylpyrazolium methyl sulfate (500 g) was extracted with ether.

The aqueous layer is separated and treated with dilute perchloric acid (10') to give a solid. After soaking for 1 hour, the solid was separated by filtration and dried, resulting in a cream-colored solid with a melting point of 160°C to 161°C.
．． 1 night, 60%).

The following values are obtained by analysis. Analysis result: Calculated value: C, 4th, 7C, C, 53.75 as N204: Day, 5.48
:N, 8-96; C, 11.34 Experimental value: C, 54.0: Sun, 5.40: N, 8-90;
C, 11-48 As shown in Table 4 below, suitable pure, technical or crude 1 of the following structure as the raw material:
, 2 dimethyl-3,5 monolayer pyrazolium methyl sulfate, some typical perchlorates are prepared by the method of Reference Example 5 above.

Table 4 Some of the compounds that can be produced by the above method include:

3,5-dibenzyl-1,2-dimethylpyrazolium perchlorate; 3-penzyl-5-cyclohexenyl 1,
2-dimethylpyrazolium perchlorate; 1,2-dimethyl-3-(1-methylcyclohexyl)-5-phenylpyrazolium perchlorate; 3-benzyl-1,2-dimethyl-5-(p-methylthiophenyl ) Pyrazolium perchlorate; 3-cyclohexylmethyl-1,2-dimethyl-5-phenylpyrazo IJum perchlorate: 3,5-
Dicyclohexylmethyl-1,2-dimethylpyrazolium perchlorate; 3-penzyl-5-(2-carboxyphenyl)-1,2-dimethylpyrazolium perchlorate;
3-penzyl-5-(2-rubomethoxyphenyl)-1,2-dimethyl-pyrazolium perchlorate; 3-penzyl-5-(2-rubomethoxyphenyl)-1,2-
Dimethylpyrazolium perchlorate.

Reference Example 6 Preparation of 5-cyclopropyl-1,2-dimethyl-3-phenylpyrazolium iodide 5-cyclopropyl-1,2-dimethyl-3-phenylpyra dissolved in water (100') The solution of zolium methyl sulfate (12.3 m) is extracted with ether.

The aqueous layer is separated and treated with a saturated aqueous solution of potassium iodide.
After 3 eaves, the solid was separated in a furnace and dried to yield a pale yellow solid (4.7 min, 36%) with a melting point of 150°C to 152°C.

The analysis results are as follows. Analysis result: Calculated value: C, 4
Sun, C as 7N21, 49.42: Sun, 5.04: N, 8.24 Experimental value:
C, 49.07; Sun, 5.06; N, 8.16 The iodides listed in Table 5 below were prepared by the method of Reference Example 6.
The appropriate pyrazolium methyl sulfate of the following structure is prepared in place of the 5-cyclopropyl-1,2-dimethyl-3-phenyl pyrazolium methyl sulfate.

Table 5 Examples of compounds produced by the above method include:

3,5-dicyclohexenyl-1,2-dimethylpyrazoium iodide; 3,5-di-t-butyl-1,2-dimethylpyrazolium iodide; 3,5-dicyclopropylmethyl-1,2- Dimethylpyrazolium iodide: 3,5
-dicyclopropyl-1,2-dimethyl-pyrazolium iodide; 3,5-dicyclopropyl-1,2-dimethylpyrazolium iodide; 1,2-dimethyl-3-(2-methylcyclohexyl)-5 -Phenylpyrazolium iodide; 3-(p-chlorophenyl)-5-cyclobentyl-1,2-dimethylpyrazolium iodide; 3-cyclohexyl-5-(p-cyanophenyl)-1,2-dimethylpyrazolium Iodide; 3-cyclobentylmethyl-1
,2-dimethyl-5-phenylpyrazolium iodide; 3
-(2-rubomethoxyphenyl)-5-cyclohexenyl-1,2-dimethylpyrazolium iodide: 3-(2
-carpoxyphenyl)-5-cyclohexyl 1,2
-Dimethylpyrazolium iodide; 3-(2-carboxyphenyl)-5-cyclobenthyl-1,2-dimethylpyrazolium iodide.

Example 1 The post-emergence selective herbicidal action of the compounds of the present invention is demonstrated by the following test.

Here, various monocotyledonous and dicotyledonous plants are treated with test compounds dispersed in a water-acetone mixture. In this test, young plants are grown in a Jiffy flat for approximately two weeks. The test compound was applied to plants in a 50/50 acetone/water mixture containing 0.5% polyoxyethylene sorbitan monolaurate surfactant by operating the spray nozzle at 40 psi for a period of time. The active compound is dispersed in an amount sufficient to provide about 0.5 to 4 pounds of active compound. After deforestation, the plants are placed on greenhouse shelves and cared for in a normal manner commensurate with conventional greenhouse practices. After 5 weeks of treatment, young plants are tested and evaluated using the evaluation method described below. The results obtained are shown in Tables 6 and 7 below.
The present compounds were found to be very effective in controlling many broadleaf weeds and undesirable grasses. M. in Table 6. In compound 1, R3 is phenyl,
This is a control example in which R4 is methyl, which is outside the scope of the present invention, and has no herbicidal activity. Evaluation method % difference in growth from control material *0 - Ineffective 0 1 - Possibly effective 1 - 102 Effective for Ikkuni 11 - 253 Moderately effective
26-405 - obviously harmful
41-606 - Has weeding effect 6
1~757-Good weeding effect 76~90
8-Almost complete weeding 91-999-Complete weeding 1004- Abnormal growth, ie, clearly physiologically malformed, but overall less effective than 5 in terms of evaluation.

* Based on visual determination of standing condition, size, vigor, bleaching growth malformations and overall plant appearance.

Plant abbreviations: MUichikarashina (Brassicaka 戊r) PI-Akaza (Amaranth order re○ofle)
Fox s) BA-Nobie (Echi skin chioacmsga
lli) CR Ihiyo (Digtanasan■in
alis) WO-Wild oat (Avena netua)
WH-Wheat (Tritjc maestivum) MG
-Morning glory (lpomoeapmp rainbow ea) Barley- (Hor
deumv mountaingare) VL-L Chibi (Abutil
ontheophrasti) F○-Enokorogusa (S
eneriaviridis) RI-Rice (Konggen asati)
va) Table 6 Table 7 Example 2 The pre-emergence effect of the compounds of the invention is demonstrated by the following test.

Here, a 50/50 acetone/water mixture containing 0.5% by volume of polyoxyethylene sorbitan monolaurate surfactant and a sufficient amount of test compound is added to a pot containing seeds of the test plant species. The compound is fed at 10 pounds per acre when the mixture is applied.
The pots were prepared on the day of the weeding treatment by placing 100 ml of soil as a base in each plastic pot, and then placing morning glories, tomatoes,
Place the seeds of wild oat and sagebrush on top of this base and cover with a 50'(3'8 to 1/2 inch) layer.
Each of the other eight plant seeds listed below was mixed separately with
Add the soil and seed mixture to the pot. Then fill the pot with soil, level it out, and flood the soil with water before applying the herbicide.
This pre-wetting spreads the herbicide solution evenly over the surface of the pot and protects the weed seeds from the harm of the acetone. Add each of the 12 weeds to a separate pot.

The pots are trimmed into 10 x 12 inch flats prior to chemical treatment. The planted pots are treated with the 5x test solution and placed on a shelf in the greenhouse.

After treatment, the pots are watered and placed in a greenhouse for three weeks. After 3 weeks, the results shown in Table 8 below are obtained.

), and No. in the same table. No. 1 is a 3,5-diphenylpyrazolium salt which is outside the scope of the present invention, and is a control example having no pre-emergence herbicidal effect. Common names of plant species used for evaluation of herbicide efficacy before germination Abbreviation Scientific name: Cypems rotundus Akagi LA Chehada podimal
bum Takarashi MU Brassjca
A
mbrosiaartemisjif()lja morning glory
MG 1pomoeaPIUPu1ea Nobie BA EchjnochloaC
mSgalli Ohishiba CR Dig female ri
aSangujnalis Enokorogusa FO Seria viridis Wild oat WO Avenafatua tomato r.

LyC. perSicOnesC mountain entum/chibi VL Abutjlon ratio eop
The evaluation method used in these tests is the same as described in Example 7 above.

Table 8 Example 3 Compared to 3,5-diphenylpyrazo IJum compounds, the compounds of the present invention have a post-emergence herbicidal effect that is extremely effective, especially against broad-leaved weeds, when used at low doses of pounds per acre. The results of the test will be shown below.

The test method and evaluation method are the same as in Example 1. The results obtained are shown in Table 9. That is, at dosages of 4 lbs./acre or less, the compounds of the present invention are 3,5-
MU (mustard) than diphenylpyrazolium compounds
, P1 (Akagi), and MG (Morning Glory) have a remarkable herbicidal effect on broad-leaved weeds. Table 9 Next, embodiments of the present invention are listed.

'1} Applying a herbicidally effective amount of a compound of general formula 1 as claimed in the claims to the foliage of the undesirable plant at a rate of 0.25 to 10.0 pounds of said compound per acre of treated area. Methods for controlling undesirable plants.

[2- R3 is a phenyl group and R4 is C2-C, . selectively suppressing post-germinated broad-leaved weeds in places where there are cereals such as barley, wheat, and rice according to the method of item {11] using the compound of the general formula 1 of the claims, which is an alkyl group of how to.

(Kalpa R4 is C3-C7 cycloalkyl, R3 is C3
1C7 cycloalkyl or -CH2)n→≧》 in which R, 2 are methyl groups, and X, n and m are all as defined in the claims. A method for controlling broad-leaved weeds and undesirable grasses before or after germination, which comprises applying a herbicidally effective amount of Compound 1 described above.

Claims (1)

[Claims] 1 General formula ▲ Numerical formula, chemical formula, table, etc. ▼ (Here, R_1 and R_2 are methyl groups, respectively; R_3 and R
_4 is a group selected from the group consisting of cycloalkyl groups C_3 to C_6, alkyl groups C_2 to C_1_1, and ▲ mathematical formulas, chemical formulas, tables, etc. ▼ groups, and X is I, CH_
3SO_4 or CIO_4, m is an integer equal to the valence of the anion, and n is 1 or 0. However, if n = 0, ▲ There are mathematical formulas, chemical formulas, tables, etc. ▼ The group is limited to only one of R_3 and R_4) A weed control composition containing a pyrazolium compound represented by the following as an active ingredient.