JPH03109302A - 4-pyrazolamides and herbicides containing them as active ingredients - Google Patents

Abstract

NEW MATERIAL:A compound of formula I (R<1> is 1-4C alkyl or phenyl; R<2> is 1-4C alkyl; R<3> is H or R<2>; R<4> is R<2> or 2-4C alkoxy; X is halogen, cyano or phenoxy). EXAMPLE:N-Methyl-1-phenyl-3-methyl-5-cyano-4-pyrazol carboxamide. USE:As an active ingredient for agricultural chemicals, especially herbicides. The compound of formula I exhibits a highly wide herbicidal spectrum, has high safety to crops and is useful for the pre-germination treatment and growing period treatment of upland weeds such as Graminales digitaria and Chenopodium album and of rice field weeds such as Potederiaieae monochoria and Echinochloa crusgalli oryzicola, thereby permitting to use as a selective herbicide for the cultivation of crops such as rice and wheat. PREPARATION:A compound of formula II (Y is Cl, Br, OH, OCH3, OC2H5 or OC3H7) is reacted with an amino compound of formula III at 0-30 deg.C to give a compound of formula I in the presence of a base such as triethylamine in a polar solvent such as a halogenated hydrocarbon when Y is Cl or Br.

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial Field of Application] The present invention relates to novel 4-pyrazoleamides. The compounds of the present invention are effective as agricultural chemicals, especially herbicides.

[Prior Art] Various 4-pyrazolamide derivatives have been known. For example, JP-A-60-172967, JP-A-6
Compounds having herbicidal activity are described in JP-A No. 0-172968, JP-A No. 61-72757, and JP-A No. 63+258858, but in these compounds, the 3-position of the pyrazole ring is Limited to hydrogen atoms.

Also, JP-A-62-249975, JP-A-63-
Publication No. 48269 and Pe5t, Bio, Phy
, 25.163 (1986) describes compounds having bactericidal activity, but even in these compounds, the amine moiety of the amide is limited to anilines.

[Problems to be Solved by the Invention] As mentioned above, many 4-pyrazolamide derivatives having herbicidal activity have been proposed, but there are still none that have both safety and satisfactory herbicidal activity against certain crops. However, there is a strong demand for herbicides that have these properties.

[Means for Solving the Problems] In order to deal with this situation, the inventors of the present invention have made extensive studies and have discovered novel 4-pyrazoleamides useful as agricultural chemicals, especially herbicides, and have completed the present invention. I ended up doing it.

That is, the gist of the present invention is as follows. -C4 alkyl group, R4 is 0
It represents a 1 to C4 alkyl group or a 02 to C4 alkoxyalkyl group, and X represents a halogen atom, a cyano group, or a phenoxy group. ) and herbicides containing this as an active ingredient.

The present invention will be explained in detail below. In the above general formula (I), R1 is a C1 to C4 straight or branched chain such as a methyl group, ethyl group, n-propyl group, isopropyl group, n-butyl group, isobutyl group, 5ec-butyl group, t-butyl group, etc. Indicates a chain alkyl group or phenyl group. R2 represents a C1 to C4 straight or branched alkyl group such as a methyl group, ethyl group, n-propyl group, isopropyl group, n-butyl group, isobutyl group, sec-butyl group, or t-butyl group. R3 is a hydrogen atom; methyl group, ethyl group, n-propyl group, isopropyl group, n-butyl group, isobutyl group,
Represents a C1 to C4 straight or branched alkyl group such as a 5ec-butyl group or a t-butyl group, R4 is a methyl group,
C1 to C4 straight or branched alkyl groups such as ethyl group, n-propyl group, isopropyl group, n-butyl group, isobutyl group, sec-butyl group, t-butyl group; methoxymethyl group, methoxyethyl group, 02-C such as methoxypropyl group, ethoxyethyl group, propoxymethyl group, etc.
4 represents an alkoxyalkyl group, and X represents a halogen atom such as a fluorine atom, a chlorine atom, or a bromine atom; a cyano group: a phenoxy group.

The compound of the present invention represented by the general formula (I) can be produced, for example, according to the following reaction formula.

(II) (1)(
In the above reaction formula, R1, R2, R3, R4 and X are as defined in the general formula (I) above, and Y represents a chlorine atom, a bromine atom, a hydroxyl group, a methoxy group, an ethoxy group or a propoxy group. . ) In the above general formula (II), when Y represents a chlorine atom or a bromine atom, aromatic hydrocarbons such as benzene, toluene or xylene; ketones such as acetone, methyl ethyl ketone or methyl isobutyl ketone; chloroform or methylene chloride halogenated hydrocarbons such as; water; esters such as methyl acetate or ethyl acetate; polar solvents such as tetrahydrofuran, acetonitrile, dioxane, N,N-dimethylformamide, N-methylpyrrolidone or dimethylsulfoxide at 0 to 30°C. Preferably 0-5°
The compound represented by the general formula (I) can be obtained by reacting the compound represented by the general formula (III) at C in the presence of a base. Examples of the base include sodium hydroxide, potassium hydroxide, sodium carbonate, potassium carbonate, pyridine, and triethylamine.

Further, in the general formula (II), Y represents a hydroxyl group, a methoxy group, an ethoxy group, or a propoxy group, and the general formula (III)
When the amine represented by ) is a lower mono- or dialkylamine, the compound of the general formula (I) can be obtained by carrying out the reaction in the above-mentioned solvent at 10 to 50°C.

The compound represented by the above general formula (II) can be produced, for example, according to the method described in JP-A-61-72757.

The compound of the present invention thus obtained can be used as a herbicide as it is, but it is usually mixed with an inert liquid or solid carrier, and a suitable surfactant is added thereto to form an emulsion, powder, granule, etc. Used in the form of hydrating powders, etc.

Liquid carriers include toluene, xylene, methylnaphthalene, cyclohexane, butanol, glycol, dimethyl sulfoxide, dimethylformamide, acetone,
Methyl isobutyl ketone, animal and vegetable oils, fatty acids, fatty acid esters, water, etc., and solid carriers such as clay, kaolin clay, talc, bentonite, diatomaceous earth, silica, calcium carbonate, and vegetable bases such as soybean flour and wheat flour. Examples include powder. Furthermore, if necessary, it can be used in combination with other active ingredients, such as agricultural fungicides, insecticides, nematicides or other herbicides, plant growth regulators, soil conditioners, and fertilizers. Further, in order to obtain a reliable herbicidal effect, multiple auxiliaries such as a spreading agent, an emulsifier, a wetting agent, and a fixing agent may be appropriately mixed.

The application amount of the herbicide of the present invention varies depending on the type of compound used, target weeds, treatment time, treatment method, soil properties, etc., but usually 0.05 to 5 kg of the active ingredient per hectare, preferably A range of 0.1 to 2 kilograms is suitable.

The weeds targeted by the herbicide of the present invention and the timing of treatment include, for example, whiteweed, pigweed, Japanese knotweed, Japanese knotweed, Japanese commonweed, purslane, chickweed, hotokenoza, black-and-white weed, blackberry, foxtail grass, sycamore, cyperus japonica, and green grass in paddy fields. For example, it is possible to control weeds such as azalea, japonica, horsetail, Japanese chickweed, Japanese chickweed, Japanese millet, Japanese grasshopper, Japanese cypress, and other weeds in both pre-emergence treatment and growing season treatment. In addition, the compounds of the present invention can be used in, for example, rice, sunflower, potato, wheat, barley, sugarcane,
It can be used as a selective herbicide in the cultivation of crops such as corn and soybeans.

Furthermore, the compound of the present invention exhibits high herbicidal activity against weeds that have been difficult to control with existing herbicides, such as Japanese sagebrush, Japanese sagebrush, wild mustard, Japanese violet, and Japanese violet. have

The scope of application of the compound of the present invention is not limited to the above-mentioned types of plants, and it can be used for other plants by the same application method.

[Example 1] Next, the present invention will be explained in more detail with reference to production examples and test examples of the compounds of the present invention, but the present invention is not limited to the following examples unless the gist thereof is exceeded.

Example 1 Preparation of N-(4-dimethylamino)-1-phenyl-3-methyl-5-bromo-4-pyrazolecarboxamide l-phenyl-3-methyl-5-bromo-4-pyrazolecarboxylic acid chloride 3. 14g chloroform 30m
The e solution was added dropwise to a solution of 1.0 g of a 50% dimethylamine aqueous solution and 1.02 g of triethylamine in 10 ml of chloroform at 0 to 5°C. After the dropwise addition, the mixture was stirred for 2 hours, poured into ice water, and extracted with chloroform. The chloroform layer was washed with an aqueous sodium carbonate solution, water, and saturated brine. The crystals precipitated by concentration under reduced pressure were washed with n-hexane to obtain 2.90 g of the compound (No. 6) listed in Table 1. The NMR of this compound was as follows.

'HNMR (CDC1a) δppm; 2.40 (S
, 3H), 3.10 (S, 6H), 7.50
(m, 5H) Example 2 N-methyl-1-phenyl-3-methyl-5-cyano-
Preparation of 4-pyrazolecarboxamide 1-phenyl-3
-2.69 g of methyl-5-cyano-pyrazolecarboxylic acid ethyl ester and 0.77 g of 40% methylamine aqueous solution
g was stirred in 5 ml of N-methylpyrrolidone at 20-25°C for 3 hours. Pour into ice water, pour the precipitated crystals to the bottom of the furnace, wash with water, and dry to obtain the compound listed in Table 1 (No. 1) 2.
16g was obtained. The NMR of this compound was as follows.

Electron HNMR (CDCl3) δppm; 2.6 (S
, 3H) t 3.0 (d, 3H).

6.15 (b, IH)t 7.4~7.85 (m
, 5H) Example 3 According to the method of Example 1 or 2, the compounds listed in Table 1 were obtained.

Table 1 Next, formulation examples of the compounds of the present invention are shown. In addition, below is [section],
"%" means "parts by weight" and "% by weight", respectively.

Formulation Example 1 50 parts of the compound listed in Table-1, Carplex #80 (
Contains 20 parts of Shionogi Pharmaceutical Co., Ltd. (trade name), 25 parts of N,N kaolin clay (Ueya Kaolin Co., Ltd., trade name), and 5 parts of higher alcohol sulfate ester surfactant Tsurupol 8070 (Toho Chemical Co., Ltd., trade name). The mixture was mixed and pulverized uniformly to obtain a wettable powder containing 50% of the active ingredient.

Formulation Example 2 10 parts of the compound listed in Table 1 was dissolved in a mixed solvent consisting of 70 parts of xylene and 10 parts of dimethylformamide, and the polyoxyethylene surfactant Tsurupol 3 was added to the solution.
005X (Toho Kagaku Co., Ltd., trade name) was added to obtain an emulsion containing 10% of the active ingredient.

Formulation Example 3 20 parts of the compound listed in Table 1, 8 parts of ethylene glycol mixed in advance, Tsurpol AC3032 (
Toho Chemical Co., Ltd. (trade name)), 0.5 parts of xanthan gum, and 63.5 parts of water were mixed well. Next, this slurry-like mixture was wet-milled using a Dyno Mill (Shinmaru Enterprises) to obtain a stable flowable agent containing 20% of the active ingredient.

Test Example 1 Soil Treatment Test A 1/5000 are resin pot is filled with alluvial volcanic ash clay loam, soybeans and corn are sown at a depth of 2 cm, and weed seeds of crabgrass, blueberry, whiteberry, and Japanese knotweed are added to the soil surface layer 1 cm. evenly mixed within.

A wettable powder containing the compounds of the present invention (No. 1) and (No. 4) shown in Table 1 as active ingredients, obtained in the same manner as in Formulation Example 1 on the day after sowing, is diluted with a predetermined amount of water and sprayed. Processed.

On the 28th day after the chemical treatment, the effects on various plants were investigated according to the criteria below, and the results are shown in Table 2.

Table-2 Judgment criteria 0: No herbicidal effect (phytotoxicity) 1: Herbicidal efficacy (phytotoxicity) of 24% or less 2: 25-34 3: 35-44 4: 45-54 5: 55-64 6.65-74 7 - 75-84 8:85-94 9:95-99 10: 100 Test Example 2 Leaf Treatment Test A 1/5000 are resin pot was filled with alluvial volcanic ash clay loam, and the following plants were sown. Novie 1 and 5 leaf stage, Shiroza 2 leaf stage, Japanese knotweed 2 leaf stage, mustard 2 leaf stage,
When corn reached the 3-leaf stage and wheat reached the 3-leaf stage, the compound of the present invention (N
o.

An emulsion containing 1) as an active ingredient was diluted with a predetermined amount of water and sprayed.

On the 21st day after the chemical treatment, the effects on various plants were investigated using the same criteria as Test Example 1, and the results are shown in Table 3.

[Effects of the Invention] The 4-pyrazoleamides of the present invention have a very wide herbicidal spectrum and are highly safe for crops, making them useful as herbicides.

Claims (2)

[Claims] (1) The following general formula (I) ▲There are mathematical formulas, chemical formulas, tables, etc.▼... (I) (In the above formula, R^1 represents an alkyl group or phenyl group of C_1 to C_4, and R^2 is Represents an alkyl group of C_1 to C_4, R^3 represents a hydrogen atom or an alkyl group of C_1 to C_4, R^4 represents an alkyl group of C_1 to C_4 or an alkoxyalkyl group of C_2 to C_4, and X is a halogen atom. , which represents a cyano group or a phenoxy group. (2) A herbicide containing the 4-pyrazoleamide according to claim (1) as an active ingredient.