JPH0559882B2 - - 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 phenylpyrimidine 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 developed the following general formula as an excellent herbicide that satisfies the above properties. (However, in the formula, R ₁ is a halogen atom, an alkoxy group,
It represents 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,
Indicates an alkoxy group, alkylthio group, alkoxyalkyl group or alkylthioalkyl group, R ₄
represents a hydrogen atom or an alkyl group, R ₅ , R ₆ and
R ₇ is the same or different hydrogen atom, halogen atom,
It represents an alkyl group, an alkenyl group, an alkynyl group, an alkoxy group, or an alkylthio group. ) have already been proposed (Japanese Patent Application No. 111077/1983 and others). Generally, when the purpose is weed control, it is fully expected that the larger the amount of herbicide used, the more completely the weeds will be killed over a long period of time. However, no matter how good and low-toxic herbicides are, if they are used in amounts far exceeding the appropriate amount required for the above-mentioned purposes, they tend to cause chemical damage to crops. That is, ecological and morphological differences between crops and weeds are factors in herbicidal selectivity.
There are four possible causes: differences in physiological functions, differences in absorption sites, and differences in growth stages, but under harsh conditions such as using herbicides at extremely high concentrations,
There is a good chance that it will cause phytotoxicity to crops. The present inventors have conducted research on various herbicide compositions with the aim of using the N-substituted-chloroacetanilide represented by the above general formula as a herbicide more safely on crops. As I continued to work hard, I realized that N- shown in the above general formula
It has been found that a herbicidal composition containing a substituted-chloroacetanilide and a specific phenylpyrimidine derivative as active ingredients is extremely safe for crops while maintaining excellent herbicidal effects. 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 ₃ is a halogen atom, an alkoxy group,
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, Indicates an alkynyl group or an alkoxy group. ) N-substituted-chloroacetanilide represented by the following general formula [] (However, in the formula, R ₈ , R ₉ and R ₁₀ are the same or different hydrogen atoms, halogen atoms, substituted or unsubstituted alkyl groups, alkoxy groups, alkoxycarbonyl groups, cyano groups, carboxyl groups, hydroxyl groups, nitro groups, or R ₁₁ and R ₁₂ represent the same or different hydrogen atoms, halogen atoms, substituted or unsubstituted alkyl groups, alkoxy groups, or hydroxyl groups, and R ₁₃ represents hydrogen atoms, halogen atoms, substituted or unsubstituted alkyl groups, or hydroxyl groups. Alkyl group, alkoxy group, hydroxyl group,
The amino group represents a phenyl group. ) A herbicidal composition characterized by containing a phenylpyrimidine derivative represented by the following as an active ingredient. One component of the herbicidal composition of the present invention is represented by the above general formula [] and is a novel compound. In the general formula [], specific examples of the halogen atoms represented by R ₃ , R ₅ , R ₆ and R ₇ include chlorine, bromine, fluorine and iodine atoms. Furthermore, in the general formula, the alkyl groups represented by R ₄ , R ₅ , R ₆ and R ₇ may be linear or branched, and the number of carbon atoms is not particularly limited. but,
The number of carbon atoms is preferably 1 to 6 from the viewpoint of easy availability of raw materials. Specific examples of the alkyl group include methyl group, ethyl group, n-propyl group,
Examples include iso-propyl group, n-butyl group, iso-butyl group, t-butyl group, n-pentyl group, n-hexyl group, and the like. In the general formula [], R ₃ ,
The alkoxy groups represented by R ₅ , R ₆ and R ₇ are not particularly limited, but generally linear or branched saturated or unsaturated groups having 1 to 6 carbon atoms 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 above general formula [], the alkylthio group represented by R ₃ is not particularly limited and any known alkylthio group can be used, but it is generally a linear or branched saturated or unsaturated group having 1 to 6 carbon atoms. Groups are preferred.
Specific examples of commonly used alkylthio groups include methylthio group, ethylthio group, n-propylthio group, t-butylthio group, n-pentylthio group, n-hexylthio group, and allylthio group. In addition, in the general formula, the alkoxyalkyl group represented by R ₃ is not particularly limited in number of carbon atoms, but is preferably a linear or branched saturated or unsaturated group having 2 to 6 carbon atoms. Specific examples of alkoxyalkyl groups include methoxymethyl group, methoxyethyl group, ethoxymethyl group,
Examples include n-propoxymethyl group, t-butoxyethyl group, allyloxyethyl group, and the like. Furthermore, in the general formula, the alkylthioalkyl group represented by R ₃ is not particularly limited in the number of carbon atoms, but is preferably a linear or branched saturated or unsaturated group having 2 to 6 carbon atoms. Specific examples of the alkylthioalkyl group include methylthiomethyl group, methylthioethyl group, ethylthiomethyl group,
Examples include n-propylthiomethyl group, t-butylthioethyl group, and allylthioethyl group. Furthermore, 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, and 3-butenyl group. In addition, in the general formula, the alkynyl group represented by R ₅ , R ₆ and R ₇ may be linear or branched, and the number of carbon atoms is not particularly limited, but as above, the number of carbon atoms is 2 to 2. It is preferable that the number is four. Specific examples of the alkynyl group include ethynyl group, 2-propynyl group, and the like. Among the above N-substituted-chloroacetanilides, R ₃ is a 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, 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 Even when used at a low concentration of 1.5 g/a or less, the compound not only has an excellent herbicidal effect that can completely kill annual weeds such as field weeds and perennial weeds such as cypress.
Since it is completely harmless to rice even when used at a high concentration of 50 g/a, it is suitably used in the present invention. In particular, R ₃ is bonded to the thiophene ring.

〔effect〕

The herbicidal composition of the present invention described above has high safety against crops, and is characterized by high safety against rice, especially when applied in flooded fields. Among these, it exhibits excellent effects when applied to direct-seeded paddy rice cultivation. Therefore, even if the application amount is higher than when N-substituted-chloroacetanilide is used alone, phytotoxic damage to crops can be prevented or reduced.
As a result, the herbicidal composition of the present invention has N-substituted-
Weeds that could not be completely killed by applying chloroacetanilide alone at a small amount can be completely killed by increasing the amount applied, and the herbicidal effect is maintained over a long period of time. can be done. Moreover, it has the characteristic that chemical damage to crops can be prevented. 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 chloracetyl chloride 0.83
g (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%,
Calculated value for C ₁₅ H ₁₅ NSOBrCl (372.71)
It matched well with C48.20%, H4.32%, and N3.75%. In addition, when mass spectra were measured, m/
Molecular ion peak corresponding to molecular weight (M
), a peak 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 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 croacetanilide synthesized in the same manner as in Synthesis Example 1 are summarized in Table 1. Furthermore, the general formula in Table 1 corresponds to the general formula [], and A is is R ₄ , D is

【formula】 means.

【table】

【table】

【table】

【table】

【table】

【table】

[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 the compound numbers [(1) to (66)] in the synthesis examples, and phenylpyrimidine derivatives are represented by the following symbols ([A] to [Z]). ]).

【table】

[Table] Formulation example 1 5 parts by weight of compound [A], 10 parts by weight of compound (3), surfactant Solpol 800A [trademark of Toho Kagaku Kogyo Co., Ltd.]
1.5 parts by weight, 1.5 parts by weight of surfactant Detargent 60 (trademark of Lion Yushi Co., Ltd.), and Seecrite 82
Parts by weight were thoroughly ground and mixed to obtain a wettable powder. Formulation example 2 Compound [A] 10 parts by weight, compound (39) 10 parts by weight, surfactant Solpol SM100 [Toho Chemical Industry
Co., Ltd. trademark) and 65 parts by weight of xylene were thoroughly mixed to obtain an emulsion. Formulation Example 3 1 part by weight of compound [A], 10 parts by weight of compound (40), 4 parts by weight of dioctyl succinate, 4 parts by weight of sodium tripophosphate, 40 parts by weight of bentonite and 32 parts by weight of talc were thoroughly mixed and ground, and mixed with water. After adding and kneading, the mixture was granulated and dried, and the granules were sized to 14 to 32 mesh to obtain granules. Example 1 An Agner 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 layer, and tubers of Japanese cypress and Japanese cypress are sown. embedded. Furthermore, 100 rice seeds (variety name: kyallose) were sown on the soil surface. After that, the rice was grown in a glass room at 20 to 25℃ under water conditions of about 3 cm, and 7 days after sowing (when the wildflowers were at about 0.8 leaf stage), a hydrating agent prepared according to Formulation Example 1 was added to the rice. The solution was diluted 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 display: Weed suppression rate (%) 5:100 (complete death) 4:75-99 3:50-74 2:25-49 1:1-24 0:0 (no effect observed at all) Also, paddy rice damage Regarding rice grains, out of 100 rice grains, those that did not grow normally were compared to the untreated plot and expressed on a five-point scale from - to +++. Rice damage (%) -: Normal (0) ±: Slight damage (1-10) +: Slight damage (11-29) ++: Medium damage (30-69) +++: Severe damage (70-100)

【table】

【table】

【table】

[Table] Example 2 In the same manner as in Example 1, the phytotoxicity of compositions containing various N-substituted chloroacetanilides and phenylpyridine derivatives was investigated, and the results are shown in Table 3. The criteria for paddy rice phytotoxicity in Table 3 are the same as in Example 1.

【table】

【table】

[Table] Comparative Example 1 Using known N-methoxymethyl-2',6'-diethyl-chloroacetanilide [alachlor] and phenylpyrimidine derivative [A], Example 1
The herbicidal effect and chemical damage to paddy rice were investigated in the same manner as above. The results are shown in Table 4.

【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 ₃ is a halogen atom, an alkoxy group,
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, Indicates an alkynyl group or an alkoxy group. ) N-substituted-chloroacetanilide represented by and the following general formula (However, in the formula, R ₈ , R ₉ and R ₁₀ are the same or different hydrogen atoms, halogen atoms, substituted or unsubstituted alkyl groups, alkoxy groups, alkoxycarbonyl groups, cyano groups, carboxyl groups, hydroxyl groups, nitro groups, or R ₁₁ and R ₁₂ represent the same or different hydrogen atoms, halogen atoms, substituted or unsubstituted alkyl groups, alkoxy groups, or hydroxyl groups, and R ₁₃ represents hydrogen atoms, halogen atoms, substituted or unsubstituted alkyl groups, or hydroxyl groups. Alkyl group, alkoxy group, hydroxyl group,
Indicates an amino group or a phenyl group. ) A herbicidal composition comprising a phenylpyrimidine derivative represented by the following as an active ingredient.