JPH053445B2 - - Google Patents

Description

[Detailed description of the invention]

[Industrial Application Field] The present invention relates to a herbicidal composition characterized by containing an N-substituted chloroacetanilide and a pyrazole derivative as active ingredients. [Problems to be solved by the prior art and the invention] The following four properties are essentially required of herbicides. First, it must be safe for crops; second, it must have a broad herbicide spectrum necessary to completely kill the many types of weeds that grow in crop-growing areas; and third, it must be safe for crops. Fourth, it has long-lasting efficacy and, fourth, it has more effective herbicidal action when applied in small amounts. The present inventors have conducted extensive research with the aim of developing an excellent herbicide that satisfies the above properties, and have obtained the following general formula [] (However, in the formula, R ₁ represents a halogen atom, an alkoxy group, an alkylthio group, an alkoxyalkyl group, or an alkylthioalkyl group, and R ₂ and R ₃ are the same or different hydrogen atoms, halogen atoms, alkyl groups, alkoxy groups, It represents an alkylthio group, an alkoxyalkyl group, or an alkylthioalkyl group, R ₄ represents a hydrogen atom or an alkyl group, R ₅ ,
R ₆ and R ₇ represent the same or different hydrogen atoms, halogen atoms, alkyl groups, alkenyl groups, alkynyl groups, alkoxy groups, or alkylthio groups. ) The N-substituted chloroacetanilide represented by the following has already been proposed (JP-A-58-111077 and others). The present inventors further discovered that a herbicide composition containing an N-substituted chloroacetanilide represented by the above general formula [] and a specific pyrazole derivative as active ingredients exhibits a synergistic effect that could not be expected from the properties of each alone. In other words, it was discovered that it has a wide herbicidal spectrum at a low dose. Based on these new findings, the present inventors have completed and proposed the present invention. [Means for solving the problems] The present invention is based on the following general formula [] (However, in the formula, R ₁ , R ₂ and R ₃ represent the same or different hydrogen atoms, halogen atoms, alkyl groups, alkoxy groups, alkylthio groups, alkoxyalkyl groups or alkylthioalkyl groups, and R ₄ represents a hydrogen atom or an alkyl R ₅ , R ₆ and R ₇ are the same or different hydrogen atoms, halogen atoms, alkyl groups, alkenyl groups, alkynyl groups, alkoxy groups, or alkylthio groups. Acetanilide and the following general formula [] (However, in the formula, R ₈ and R ₉ are the same or different hydrogen atoms or alkyl groups, Y is a hydrogen atom, a halogen atom, an alkyl group, or a nitro group, n is an integer from 1 to 5, and Z is −COR ₁₀ or −SO ₂ R ₁₀
and R ₁₀ represents an alkyl group or a substituted or unsubstituted Feniel group. ) A herbicidal composition characterized by containing a pyrazole derivative represented by the following as an active ingredient. One component of the herbicidal composition of the present invention is an N-substituted-chloroacetanilide represented by the following general formula []. A small part of the N-substituted-chloroacetanilide represented by the above general formula [], that is, the 2-position of the thiophene ring

[Formula] is bonded, R ₁ is a hydrogen atom or an alkyl group, R ₂ , R ₃ and R ₄ are hydrogen atoms, R ₅ is an alkyl group,
Compounds in which R ₆ is a hydrogen atom, an alkyl group or an alkoxy group and R ₇ is a hydrogen atom, an alkyl group or a halogen atom are known from US Pat. No. 3,901,917. However, most of the other
It is a new compound. In the general formula [], specific examples of the halogen atoms represented by R ₁ , R ₂ , R ₃ , R ₅ , R ₆ and R ₇ include:
Examples include chlorine, bromine, fluorine, and iodine atoms. Furthermore, in the general formula, R ₁ , R ₂ , R ₃ , R ₅ , R ₆
The alkyl group represented by and R ₇ may be linear or branched, and the number of carbon atoms is not particularly limited. However, from the viewpoint of easy availability of raw materials, the number of carbon atoms is preferably 1 to 6. Specific examples of the alkyl group include methyl group, ethyl group, n
-propyl group, iso-propyl group, n-butyl group,
iso-butyl group, t-butyl group, n-pentyl group,
Examples include n-hexyl group. In the general formula [], the alkoxy groups represented by R ₁ , R ₂ , R ₃ , R ₅ , R ₆ and R ₇ are not particularly limited, but are generally linear or branched groups having 1 to 6 carbon atoms. Branched saturated or unsaturated groups are preferred. Specific examples of the alkoxy group that are generally preferably used include:
Methoxy group, ethoxy group, n-propoxy group, t
-butoxy group, n-pentoxy group, n-hexoxy group, allyloxy group and the like. In the general formula [], the alkylthio groups represented by R ₁ , R ₂ , R ₃ , R ₅ , R ₆ and R ₇ are not particularly limited and any known alkylthio group can be used, but they generally have 1 to 1 carbon atoms. Six straight-chain or branched saturated or unsaturated groups are preferred. Specific examples of the alkylthio group suitably used include methylthio group, ethylthio group, n-propylthio group, t-butylthio group, n-pentylthio group, n-hexylthio group, and allylthio group. In addition, in the above general formula, the alkoxyalkyl group represented by R ₁ , R ₂ and R ₃ is not particularly limited in the number of carbon atoms, but is a linear or branched saturated or unsaturated group having 2 to 6 carbon atoms. is suitable, and specific examples of the alkoxyalkyl group include methoxymethyl group, methoxyethyl group, ethoxymethyl group, n-propoxymethyl group, t-butoxyethyl group, allyloxyethyl group, and the like. Furthermore, in the general formula, the alkylthioalkyl group represented by R ₁ , R ₂ and R ₃ is not particularly limited in the number of carbon atoms, but may be a linear or branched saturated or unsaturated group having 2 to 6 carbon atoms. Examples of the alkylthioalkyl group include methylthiomethyl group,
Methylthioethyl group, ethylthiomethyl group, n-
Examples include propylthiomethyl group, t-butylthioethyl group, and allylthioethyl group. Also,
In the general formula, the alkenyl groups represented by R ₅ , R ₆ and R ₇ may be linear or branched, and the number of carbon atoms is not particularly limited. However, from the viewpoint of easy availability of raw materials, the number of carbon atoms is preferably 2 to 4. Specific examples of the alkenyl group include vinyl group, allyl group, iso-propenyl group, 2-butenyl group,
Examples include 3-butenyl group. Furthermore, in the general formula, the alkynyl groups represented by R ₅ , R ₆ and R ₇ are:
The number of carbon atoms is not particularly limited, regardless of whether it is linear or branched, but it is preferable that the number of carbon atoms is 2 to 4 as described above. Specific examples of the alkynyl group include ethynyl group, 2-propynyl group, and the like. In the above N-substituted-chloroacetanilide, R ₁ is the same or different halogen atom, alkoxy group, alkylthio group, alkoxyalkyl group, or alkylthioalkyl group, and R ₂ and R ₃ are the same or different hydrogen atoms. , halogen atom,
an alkyl group, an alkoxy group, an alkylthio group, an alkoxyalkyl group, or an alkylthioalkyl group, R ₄ is a hydrogen atom or an alkyl group,
Compounds in which R ₅ , R ₆ and R ₇ are the same or different hydrogen atoms, halogen atoms, alkyl groups, alkenyl groups, alkynyl groups, alkoxy groups or alkylthio groups may be used at a low concentration of 15 g/10a or less. However, it not only has an excellent weeding effect that completely kills annual weeds such as field weeds and perennial weeds such as water cypress, but also has an excellent weeding effect of 500 g/
Since it is completely harmless to rice even when used at a high concentration of 10a, it is suitably used in the present invention. In particular, at least one of R ₁ to _{R 3} is a substituent other than a hydrogen atom, and this substituent is bonded to the thiophene ring.

[Formula] is substituted at the ortho position, R ₄ is a hydrogen atom, and at least two of R ₅ to _{R 7} are substituents other than hydrogen atoms, and these substituents are 2 of the phenyl group. N-substituted-chloroacetanilide substituted at the 6-position and the 6-position is particularly preferably used because it has the stronger properties described above. The structure of the N-substituted-chloroacetanilide represented by the general formula [] can be confirmed by the following means. (b) By measuring the infrared absorption spectrum (IR), it is possible to observe an absorption based on the CH bond in the vicinity of 3150-2800 cm ^-1 and a characteristic absorption based on the carbonyl bond of the amide group in the vicinity of 1680-1660 cm ^-1 . I can do it. (b) Measuring the mass spectrum (MS) and calculating the composition formula corresponding to each peak observed (generally a value expressed as m/e, which is the ion mass number m divided by the ion charge number e). Accordingly, it is possible to know the molecular weight of the compound subjected to measurement and the bonding mode of each atomic group within the molecule. In other words, the sample subjected to measurement is expressed by the general formula [] When expressed as The molecular weight of can be determined. Furthermore, regarding the N-substituted-chloroacetanilide represented by the general formula [], M -Cl, M -
_COCH2Cl and

A characteristic strong peak corresponding to [Formula] is observed, and the bonding mode of the molecule can be known. (c) ¹ H-Nuclear Magnetic Resonance Spectrum ( ¹ H-NMR)
By measuring , it is possible to know the bonding mode of hydrogen atoms present in the N-substituted chloroacetanilide represented by the general formula []. ¹ H-NMR (δ, ppm:
(based on tetramethylsilane, in deuterated chloroform solvent), N-[2'-(5'-bromo)
-thienylmethyl]-N-chloroaceto-2,
Figure 1 shows a ¹ H-NMR diagram of 6-dimethylanilide. The analysis results are as follows. In other words, a singlet corresponding to 6 protons is observed at 2.0 ppm, which is the 2nd line of the phenyl group.
It can be attributed to the methyl group (d) substituted at the 6-position. A singlet corresponding to two protons was observed at 3.6 ppm, and this can be attributed to the methylene group (h) in the chloroacetyl group.
A singlet corresponding to two protons was observed at 4.75 ppm, and this can be attributed to the methylene group (c). A quartet corresponding to two protons was observed at 6.67 ppm, and this can be attributed to protons (a) and (b) substituted on the thiophene ring. A multiplet corresponding to three protons was observed at 6.95 to 7.30 ppm, and this can be attributed to protons (e), (f), and (g) substituted with phenyl groups. To summarize the ¹ H-NMR characteristics of the N-substituted chloroacetanilide represented by the above general formula [], the methylene proton of the chloroacetyl group usually appears as a singlet around 3.6 to 3.8 ppm,
When R ₄ is a hydrogen atom, the methylene proton of the aminomethylene group is a single line around 4.7 to 5.0 ppm (however, if there are substituents asymmetrically at the 2 and 6 positions on the aniline side, the methylene proton is a double line). ), and when R ₄ is an alkyl group, the methine proton of the aminomethine group is
From 5.7 to 6.7 ppm, the proton on the thiophene ring side is
5.8 to 7.4 ppm, and protons on the benzene side to 6.0 to 7.4 ppm.
It tends to show a characteristic peak at 7.7ppm. (d) Carbon, hydrogen, nitrogen, sulfur,
By determining the weight percent of each element and halogen, and subtracting the sum of the weight percent of each recognized element from 100, the weight percent of oxygen can be calculated.
Therefore, the compositional formula can be determined. In addition, the properties of N-substituted-chloroacetanilide vary depending on the types of R ₁ , R ₂ , R ₃ , R ₄ , R ₅ , R ₆ and R ₇ in the general formula [], but
Generally, it is a pale yellow or yellow viscous liquid or solid at room temperature and pressure, and many have extremely high boiling points. More specifically, as shown in the synthesis examples described later, the boiling point of the above compound tends to increase as the molecular weight increases, like general organic compounds. The compound is soluble in common organic solvents such as benzene, ether, alcohol, chloroform, carbon tetrachloride, acetonitrile, N,N-dimethylformamide, dimethylformamide, and dimethyl sulfoxide, but almost insoluble in water. The method for producing the N-substituted chloroacetanilide represented by the general formula [] is not particularly limited. A typical manufacturing method is described below. General formula [] (However, in the formula, R ₁ , R ₂ and R ₃ represent the same or different hydrogen atoms, halogen atoms, alkyl groups, alkoxy groups, alkylthio groups, alkoxyalkyl groups or alkylthioalkyl groups, and R ₄ represents a hydrogen atom or an alkyl group, and R ₅ , R ₆ and R ₇ are the same or different hydrogen atoms, halogen atoms, alkyl groups, alkenyl groups, alkynyl groups, alkoxy groups, or alkylthio groups. Formula _ClCH2
By reacting with chloroacetyl halide represented by COX (where X represents a halogen atom), N-substituted-chloroacetanilide represented by the general formula [] can be obtained. The aniline derivative represented by the above general formula [], which is a raw material, can be obtained by any method. In the reaction between the compound represented by the above general formula [] and chloroacetyl halide, the molar ratio of both compounds may be appropriately determined as necessary, but it is usually the same molar ratio or a slightly excess molar amount of chloroacetyl halide. It is common to use Further, in the above reaction, hydrogen halide is produced as a by-product. This hydrogen halide reacts with the aniline derivative represented by the general formula [] in the reaction system, causing a decrease in the yield of the product, so a hydrogen halide scavenger is usually allowed to coexist in the reaction system. is preferred. The hydrogen halide scavenger is not particularly limited, and any known one can be used. Examples of the scavenger that are generally suitably used include trialkylamines such as trimethylamine, triethylamine, and tripropylamine, pyridine, sodium alcoholate, and sodium carbonate. It is generally preferable to use an organic solvent in the reaction. Examples of solvents preferably used include benzene, toluene, xylene,
Aliphatic or aromatic hydrocarbons or halogenated hydrocarbons such as hexane, heptane, petroleum ether, chloroform, methylene chloride, and ethylene chloride; Ethers such as diethyl ether, dioxane, and tetrahydrofuran; Ketones such as acetone and methyl ethyl ketone ; Nitriles such as acetonitrile; N,N-dimethylformamide,
Examples include N,N-dialkylamides such as N,N-diethylformamide; dimethyl sulfoxide and the like. The order of addition of raw materials in the reaction is not particularly limited, but generally, the aniline derivative represented by the general formula [] is dissolved in a solvent, the mixture is charged into a reactor, and the chloroacetyl halide dissolved in the solvent is added under stirring. Good. Of course, it is also possible to continuously add raw materials to the reaction system and take out the produced reactants continuously from the reaction system. The temperature in the reaction can be selected from a wide range, generally -20°C to 150°C, preferably 0°C to 120°C.
It is sufficient to choose from the range of °C. Reaction time varies depending on the type of raw material, but is usually 5 minutes to 10 days.
Preferably, it is sufficient to select from the range of 1 to 40 hours. It is also preferable to stir the reaction mixture during the reaction. The method for isolating and purifying the desired product, ie, the N-substituted chloroacetanilide represented by the above general formula [], from the reaction system is not particularly limited, and any known method can be employed. For example, the reaction solution is cooled or allowed to cool naturally to return to room temperature or near room temperature, the reaction solvent and the remaining hydrogen halide scavenger are distilled off, and the residue is extracted with benzene. In the above operation, the salt and high molecular weight compound produced from the by-produced hydrogen halide and the hydrogen halide scavenger are separated. The benzene layer is dried with a desiccant such as Glauber's salt or calcium chloride, and then benzene is distilled off and the residue is vacuum distilled to obtain the desired product.
In addition to isolation and purification by vacuum distillation, it can also be purified by chromatography or, if the product is a solid, by recrystallization from a solvent such as hexane. As another method for producing the N-substituted chloroacetanilide represented by the general formula [], the following method is also preferably employed. general formula (However, in the formula, R ₁ , R ₂ and R ₃ are the same or different hydrogen atoms, halogen atoms, alkyl groups, alkoxy groups, alkylthio groups, alkoxyalkyl groups,
It represents an alkylthioalkyl group, R ₄ represents a hydrogen atom or an alkyl group, and X represents a halogen atom. ) and the general formula (However, in the formula, R ₅ , R ₆ and R ₇ are the same or different hydrogen atoms, halogen atoms, alkoxy groups,
Indicates an alkylthio group. ) The N-substituted-chloroacetanilide represented by the above general formula [] can also be obtained by reacting with chloroacetanilide represented by the formula []. The substituted thiophene and the chloroacetanilide used as raw materials can be obtained by any method. In addition, the conditions and isolation and purification method used to carry out this reaction are almost the same as those used in the reaction of the aniline derivative represented by the general formula [] with chloroacetyl halide as described above. conditions can be adopted. The N-substituted-chloroacetanilide represented by the above general formula [] has a wide herbicidal spectrum against annual weeds such as field weeds, Japanese grasshoppers, and bulrushes that occur in rice fields, as well as perennial weeds such as Japanese cypress and Japanese cypress, It is also an excellent herbicide that can efficiently control paddy rice without causing chemical damage. The other component of the herbicide composition of the present invention has the following general formula [] (However, in the formula, R ₈ and R ₉ are the same or different hydrogen atoms or alkyl groups, Y is a hydrogen atom, a halogen atom, an alkyl group, or a nitro group, n is an integer from 1 to 5, and Z is −COR ₁₀ or −SO ₂ R ₁₀
and R ₁₀ represents an alkyl group or a substituted or unsubstituted phenyl group. ) is a pyrazole derivative represented by In the above general formula [], the alkyl groups represented by R ₈ , R ₉ , R ₁₀ and Y are not particularly limited in number of carbon atoms, and any group can be used. Among these, those having 1 to 4 carbon atoms are preferred. In the present invention, suitable alkyl groups include methyl group,
Ethyl group, n-propyl group, i-propyl group, n
-butyl group, i-butyl group, sec-butyl group, t
-butyl group and the like. In addition, in the above general formula [], the halogen atom represented by Y is:
Examples include fluorine, chlorine, bromine, and iodine atoms. In addition, the substituted phenyl group represented by R ₁₀ in the above general formula [] includes those substituted with one or more substituents such as halogen atoms or alkyl groups. The halogen atom and alkyl group substituted on the phenyl group are as described above. Preferred substituted phenyl groups in the present invention include tolyl group, ethyl phenyl group, i
-propylphenyl group, t-butylphenyl group,
Dimethylphenyl group, diethylphenyl group, ethyltolyl group, trimethylphenyl group, triethylphenyl group, chlorophenyl group, fluorophenyl group, bromphenyl group, iodophenyl group, dichlorophenyl group, dibromphenyl group, trifluorophenyl group, Examples include trichlorophenyl group, methyldichlorophenyl group, ethyldibromophenyl group, methyltrichlorophenyl group, etc.
Among these, compounds in which at least one substituent is substituted at the p-position are particularly preferred. Among the pyrazole derivatives represented by the above general formula [], R ₈ and R ₉ are alkyl groups, especially methyl groups, Y is a halogen atom, especially a chlorine atom, substituted at the 2 and 4 positions of the phenyl group, and Z but

〔effect〕

The herbicidal composition of the present invention described above exhibits a herbicidal effect that cannot be expected from the properties of each component alone. That is, the herbicidal composition of the present invention exhibits an excellent herbicidal effect against perennial weeds such as cypress, for which neither the N-substituted-chloroacetanilide nor the pyrazole derivative can be expected to have much herbicidal effect when used alone. Demonstrate. Therefore, the herbicidal composition of the present invention has a broader herbicidal spectrum than that of its constituent components alone. Furthermore, it has a greater herbicidal effect at the same level as the application amount of each component alone. Moreover, it is safe for crops. Therefore, the herbicidal composition of the present invention fully satisfies the properties required of a herbicide and is extremely useful. EXAMPLES The herbicidal composition of the present invention will be specifically explained below using Examples, but the present invention is not limited to these Examples. Synthesis of N-substituted-chloroacetanilide (Synthesis Example 1) N-[2'-(5'-bromo)-thienylmethyl]-
2,6-dimethylaniline 1.81g (6.14×10 ^-3
mole) was dissolved in 40 ml of benzene, 0.81 g (7.98 x 10 ^-3 mole) of triethylamine was added, and the mixture was placed in ice water. Then 0.83g of chloroacetyl chloride
(7.37×10 ⁻³ mole) in benzene solution (15 ml) was gradually added. After stirring for 3 hours, the mixture was heated at 50°C for 1 hour. After cooling the reaction mixture to room temperature,
It was washed successively with 50 ml of water, 50 ml of 2N hydrochloric acid, and then 50 ml of water, and the benzene layer was dried over anhydrous sodium sulfate. Thereafter, it was purified by column chromatography to obtain 1.13 g of a yellow solid. As a result of measuring the infrared absorption spectrum of this product, it showed an absorption based on the C-H bond at 3110 to 2900 cm ^-1 and a strong absorption based on the carbonyl bond of the amide group at 1670 cm ^-1 . Its elemental analysis values are C48.43%, H4.05%, N3.99%, and _C15
H ₁₅ NSOB _r C which is the calculated value for Cl (372.71)
It was in good agreement with 48.20%, H4.32%, and N3.75%.
In addition, when mass spectra were measured, m/
Molecular ion peak corresponding to molecular weight (M
), the beak corresponding to M −Cl at m/e336,
A peak corresponding to M-COCH ₂ Cl at m/e293,
m/e143 (100%) The corresponding peaks are shown. Furthermore, ^{the 1} H-nuclear magnetic resonance spectrum is as shown as a specific example in the specification. From the above results, it is clear that the isolated product is N-[2'-(5'-
bromo)-thienylmethyl]-N-chloroaceto-
It became clear that it was 2,6-dimethylanilide (hereinafter abbreviated as compound (1)). The yield is N
-[2'-(5'-bromo)-thienylmethyl]-2,6
−49.5% (3.04×10 ^-3 for dimethylaniline)
mole). (Synthesis Example 2) The properties, physical properties (boiling point), characteristic absorption values in the infrared absorption spectrum, and elemental analysis results of N-substituted-chloroacetanilide synthesized in the same manner as in Synthesis Example 1 are summarized in Table 1. Furthermore, the general formula in Table 1 is the general formula [] Corresponding to, A is

[Formula] is R ₄ , D is

[Formula] means.

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[Table] Next, formulation examples and examples of the herbicide composition of the present invention are shown. In addition, in the formulation examples and examples, N-substituted-chloroacetanilides are represented by compound numbers [(1) to (66)] in the synthesis examples, and pyrazole derivatives are represented by the following symbols ([A] to [M]). expressed.

【table】

【table】

[Table] Formulation example 1 10 parts by weight of compound [A], 5 parts by weight of compound (1), surfactant Solpol 800A [trademark of Toho Chemical Industry Co., Ltd.]
1.5 parts by weight, 1.5 parts by weight of surfactant Detargent 60 (trademark of Lion Yushi Co., Ltd.) and Siegrite 82
Parts by weight were thoroughly ground and mixed to obtain a wettable powder. Formulation Example 2 20 parts by weight of compound [A], 10 parts by weight of compound (17), 15 parts by weight of surfactant Solpol SM 100 (trademark of Toho Chemical Industries, Ltd.) and 55 parts by weight of xylene were thoroughly mixed to obtain an emulsion. Ta. Formulation Example 3 10 parts by weight of compound [A], 1 part by weight of compound (39), 4 parts by weight of dioctyl succinate, 4 parts by weight of sodium tripolyphosphate, 41 parts by weight of bentonite and 40 parts by weight of talc were thoroughly mixed and ground, and water was added. After addition and kneading, the mixture was granulated, dried, and sized to 14 to 32 mesh to obtain granules. Formulation example 4 40 parts by weight of bentonite, 55 parts by weight of talc, and 5 parts by weight of sodium tripolyphosphate were ground and mixed,
After adding water and kneading, the mixture is granulated and dried to produce granules that do not contain active ingredients. Add compound [A] to 85 parts by weight of this granular material.
The mixture was impregnated with 10 parts by weight of compound (40) and 5 parts by weight of compound (40) to obtain granules. Example 1 A Wagner pot equivalent to 1/5000 are is filled with water-mixed paddy soil, and seeds of broad-leaved weeds such as Japanese grasshopper, Japanese cypress, firefly, and broad-leaved weeds such as Japanese grasshopper, Japanese cypress, and Japanese cypress are sown on the soil surface, and tubers of Japanese cypress and Japanese cypress are sown. embedded. moreover
Three rice seedlings (variety name: Akinishiki) at the 2.5 leaf stage were planted at a depth of 2 cm. After that, the rice was submerged in water to a depth of about 3 cm, and grown in a glass room at 20 to 25°C, and 7 days after transplanting (when the rice plants were at about 0.8 leaf stage) and 14 days later.
After a few days (when the wildflowers were at about the two-leaf stage), the wettable powder prepared according to Formulation Example 1 was diluted with water and a predetermined amount was dropped. After that, they are grown in a glass room and treated with chemicals.
On the 21st day, the herbicidal effect and the chemical damage to paddy rice were investigated. The results are shown in Table 2. Weeding effect Paddy rice damage suppression rate (%) -: Normal 5: 100 (complete withering) ±: Slight damage 4: 75-99 +: Slight damage 3: 50-74: Medium damage 2: 25-49 1: 1 ~24 0:0 (no effect observed at all)

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【table】 [Brief explanation of the drawing]

FIG. 1 shows a ¹ H-NMR chart of N-substituted-chloroacetanilide obtained in Synthesis Example 1.

Claims (1)

[Claims] 1. The following general formula (However, in the formula, R ₁ , R ₂ and R ₃ are the same or different hydrogen atoms, halogen atoms, alkyl groups, alkoxy groups, alkylthio groups, alkoxyalkyl groups,
or represents an alkylthioalkyl group, R ₄ represents a hydrogen atom or an alkyl group, and R ₅ , R ₆ and R ₇ represent the same or different hydrogen atoms, halogen atoms, alkyl groups, alkenyl groups, alkynyl groups, alkoxy groups, or Indicates an alkylthio group. ) N-substituted-chloroacetanilide represented by and the following general formula (However, in the formula, R ₈ and R ₉ are the same or different hydrogen atoms or alkyl groups, Y is a hydrogen atom, a halogen atom, an alkyl group, or a nitro group, n is an integer from 1 to 5, and Z is −COR ₁₀ or −SO ₂ R ₁₀
and R ₁₀ represents an alkyl group or a substituted or unsubstituted Feniel group. ) A herbicidal composition comprising a pyrazole derivative represented by the following as an active ingredient.