JPH08268813A - Herbicide composition for paddy field - Google Patents

Abstract

(57) [Summary] (Modified) [Purpose] To provide a herbicide composition for paddy fields, which can be used for a long period of time to control important weeds in paddy fields by using a smaller amount of active ingredient and having a wide suitable treatment period. [Structure] General formula (I) [In the formula, R ₁ is C ₂ H ₅ or the like; R ₂ is O—CH ₃ or the like;
₃ ) m, R ₄ is H, etc .; (R ₅ ) p is 6-CHO, 6-C
N, 6-COOCH ₃ etc., and m is 0 to 4 and n is 0.
~ 2, p is an integer of 1 to 3] and at least one or more of the furobenzopyran derivative represented by, for example, 4-
(2,4-dichlorobenzoyl) -1,3-dimethylpyrazol-5-yl-p-toluenesulfonate, or at least one or more pyrazole derivatives similar thereto, and further 2-bromo-N- (α, α -Dimethylbenzyl) -3,3-dimethylbutyramide, 1- (α,
α-dimethylbenzyl) -3- (4-methylphenyl)
Urea and 1- (α, α-dimethylbenzyl) -3-
A herbicide composition for paddy fields containing at least one selected from (2-chlorobenzyl) urea as an active ingredient.

Description

Detailed Description of the Invention

[0001]

The present invention relates to novel furobenzopyran derivatives and pyrazole derivatives, as well as 2-bromo-
N- (α, α-dimethylbenzyl) -3,3-dimethylbutyramide, 1- (α, α-dimethylbenzyl)-
3- (4-methylphenyl) urea and 1- (α, α
-Dimethylbenzyl) -3- (2-chlorobenzyl) urea and at least one selected from the group consisting of herbicidal compositions for paddy fields.

[0002]

2. Description of the Related Art Conventionally, various compounds and admixtures have been known as herbicides for paddy fields. Furthermore, recently, a mixture called a one-shot treatment agent has been developed which can control various weeds by one treatment. However, these herbicides require relatively large amounts of active ingredients, cannot be used to control important weeds accurately in a single treatment, even though they are called one-shot agents, have a short duration of effect, and have limited treatment time. There are many cases where there is a problem such as being stuck. Therefore, with a smaller amount of active ingredients, important weeds can be controlled accurately and for a long time,
Development of a herbicide for paddy fields with a wide range of treatment time is desired.

[0003]

DISCLOSURE OF THE INVENTION The present invention uses a smaller amount of active ingredient, has a wide suitable period for treatment, and can be used at any time from before the emergence of weeds before rice planting to the growing season. It is an object to provide a herbicide for paddy fields that can control important weeds in paddy fields for a long period of time.

[0004]

Means and Actions for Solving the Problems The inventors of the present invention have conducted intensive studies on a novel mixture of furobenzopyran derivatives to solve the above problems, and as a result, in addition to the furobenzopyran derivatives and pyrazole derivatives, 2-bromo -N- (α, α-dimethylbenzyl) -3,3-dimethylbutyramide, 1- (α, α-dimethylbenzyl) -3- (4-methylphenyl) urea and 1-
By mixing at least one selected from (α, α-dimethylbenzyl) -3- (2-chlorobenzyl) urea, a synergistic effect which cannot be predicted from the effects of each of them is exhibited, and the amount of the active ingredient is reduced. It is found that a paddy field herbicide that can be used at any time from the occurrence of weeds before rice planting to the growing season with a wide suitable treatment period, and that can control important weeds in paddy fields for a long period of time by using completed. That is, the present invention has the general formula (I)

[0005]

Embedded image [In the formula, R ₁ represents a lower alkyl group, R ₂ represents a lower alkyl group, a lower alkoxy group, a halogen atom or a halogen-substituted lower alkyl group, and R ₃ represents a lower alkyl group, a lower alkoxy group, a halogen atom, a halogen-substituted group. Represents a lower alkyl group, a phenoxy group or a benzyloxy group,
R ₄ represents a hydrogen atom or a lower alkyl group, R ₅ is a cyano group, a nitro group, a phenyl group, group -S (O) _q R _6, group -0S0 ₂ R _6, group -XC (= O) R ₆ , A group-XR ₇ , a group-
_{XCH (R 9) C (=} O) R 8, group -XP (= X) (XR
₆ ) ₂ , group -N (R ₉ ) R ₁₀ , group -N (R ₉ ) C (= X) R
_11, group _{-N (R 9) SO 2 R} 6, group _{-C (R 9) 2 OR 10} ,
Group _{-CH (R 9) S (O} ) q R 6, group -CH (R ₉₎ XC
(= 0) R ₁₁ , group —CH (R ₉ ) N (R ₉ ) R ₁₀ , group —C
_{H (R 9) N (R} 9) C (= X) R 11, group -CH (R _{9)
XP (= X) (XR 6} ) 2, group -C (= X) R _8, group -C
H (XR ₁₂₎ XR _13, group -C (= X) N (R 14) R 15,
Group -CH = NR _8, group -CH = CR ₁₆ R _17, group -O {C
_{(R 18) 2} r -O-} ( by connecting the adjoining carbon atoms on the benzene ring forms a 5 or 6-membered ring) or a group - {C
(R ₁₈ ) ₂ } _s — (bonding adjacent carbon atoms on a benzene ring to form a 5- or 6-membered ring), wherein R ₆ is a lower alkyl group or (lower alkyl group, lower alkoxy). Group, which may be substituted with a halogen atom), a phenyl group, R ₇ represents a hydrogen atom, a halogen-substituted lower alkyl group or an alkoxyalkyl group, and R ₈ represents a hydrogen atom, a hydroxy group, a lower alkyl group, a lower alkoxy group. , A lower alkylthio group or a phenoxy group, R ₉ represents a hydrogen atom or a lower alkyl group, R ₁₀ represents a hydrogen atom, a lower alkyl group, a halogen-substituted lower alkyl group or an aralkyl group, and R ₁₁ represents a lower alkyl group, Halogen-substituted lower alkyl group, (lower alkyl group, lower alkoxy group, optionally substituted by halogen atom) phenyl group, lower alkoxy group, phenyl group Represents a phenoxy group, lower alkylamino group or anilino group, R _12, R ₁₃ is a hydrogen atom or a lower alkyl group or R ₁₂ and R ₁₃ are each cyclized together - (CH _{2) 2} - or - (CH ₂ ) represents _3-
R ₁₄ represents a hydrogen atom or a lower alkyl group, R ₁₅ represents a hydrogen atom, a lower alkyl group, a phenyl group (which may be substituted with a lower alkyl group, a lower alkoxy group, a halogen atom) or R ₁₄ and R ₁₅ are the same. Represents a 5- or 6-membered ring which may contain an oxygen atom, a sulfur atom or a nitrogen atom, R ₁₆ represents a hydrogen atom, a cyano group or a lower alkoxycarbonyl group, and R ₁₇ represents a hydrogen atom or a lower alkyl group. ,
Represents a nitro group, a cyano group or a lower alkoxycarbonyl group, R ₁₈ represents a hydrogen atom, a lower alkyl group or a halogen atom, X represents an oxygen atom or a sulfur atom, q
Is an integer of 0 to 2, r is 1 or 2, s is 3 or 4
Represents } M is an integer of 0-4, n is an integer of 0-2, and p is 1-3.
When m, n and p are 2 or more, R ₂ , R
₃ and R ₅ may be the same or different. ] At least 1 sort (s) or more of the furo benzo pyran derivative represented by these, and 4- (2,4- dichloro benzoyl)-
1,3-Dimethylpyrazol-5-yl-p-toluenesulfonate (hereinafter referred to as Compound A), 1,3-dimethyl-4- (2,4, -dichlorobenzoyl) -5-phenacyloxypyrazole (hereinafter referred to as Compound B) And 1,3-dimethyl-4- (2,4-dichloro-3-methylbenzoyl) -5- (4-methylphenacyloxy)
At least one pyrazole derivative selected from pyrazole (hereinafter referred to as compound C) and 2-bromo-
N- (α, α-dimethylbenzyl) -3,3-dimethylbutyramide (hereinafter referred to as compound D), 1- (α, α
-Dimethylbenzyl) -3- (4-methylphenyl) urea (hereinafter referred to as compound E) and 1- (α, α-dimethylbenzyl) -3- (2-chlorobenzyl) urea (hereinafter referred to as compound F) Further, it is a herbicide composition for paddy fields, which comprises at least one or more as an active ingredient.

Of the compounds included in the composition of the present invention,
A method for producing a novel compound represented by the general formula (I) is described below.
It is shown in the formula (Formula 3). (R in the formula₁ , R₂ , R₃ , R_Four ,
R_Five , M, n and p have the above-mentioned meanings, and R ₁₉Is low
An alkyl group or a lower acyl group, Z is a halogen atom,
Represents a reactive residue such as an ester residue. )

[0007]

Embedded image That is, the compound of the general formula (I) can be produced by subjecting a tetrahydrofuran derivative represented by the general formula (II) to an intramolecular cyclization reaction. Alternatively, the obtained furobenzopyran derivative may be introduced into another compound of the general formula (I) by introducing or converting a commonly used substituent. As one example thereof, examples of introduction or conversion of the substituent R ₅ are shown in the following reaction formula 2 (formula 4) and reaction formula 3 (formula 5).

[0008]

[Chemical 4]

[0009]

Embedded image [Wherein R ₁ , R ₂ , R ₃ , R ₄ , R ₈ , R ₉ , R ₁₁ ,
R ₁₄ , R ₁₅ , m and n have the above-mentioned meanings. ] A detailed description will be added below. In Reaction Scheme 1, the compound represented by the general formula (III) is a known compound,
J. Org. Chem. , 50 , 4786 (198
5) and the method described in US Pat. No. 4,534,785. Usually, these are obtained as a mixture of α-form and β-form, but it is also possible to separate the isomers by silica gel chromatography or the like and use them in the next reaction.

The compound of the general formula (II) is prepared by the step A:
The compound of the general formula (III) is converted into n-hexane, benzene,
Toluene, xylene, diethyl ether, dioxane,
Tetrahydrofuran, dimethylformamide, dimethylsulfoxide, chlorobenzene, methylene chloride, chloroform, methyl ethyl ketone, acetone, acetonitrile, etc. in an inert solvent, potassium carbonate, sodium carbonate,
It can be obtained by using an inorganic base such as sodium hydroxide, potassium hydroxide, sodium hydride or sodium amide and reacting it with an equivalent amount or a slight excess of the substituted benzyl derivative of the general formula (IV). Alternatively, it is also possible to carry out the reaction in a two-layer system of an organic solvent such as benzene or toluene and water in the presence of a phase transfer catalyst such as a quaternary ammonium salt or a phosphate. The reaction temperature can range from -30 ° C to the boiling point of the solvent, but it is advantageous to carry out the reaction in the range of room temperature to 60 ° C. After completion of the reaction, post-treatment is carried out in the usual way, and the desired compound can be purified by recrystallization or column chromatography. The general formula (II)
Of the compounds of formula (I), compounds in which R ₁₉ is an acyl group are represented by the general formula (I
Compounds of I), wherein R ₁₉ is an alkyl group, are well-known general methods (for example, Chem. Ind., 27 , 54).
7 (1968)).

When R ₄ is a hydrogen atom, the compound of the general formula (II) thus obtained becomes a mixture of two isomers of α and β anomers in almost the same ratio as that of the compound of the general formula (III) as a raw material. These can be separated into isomers by silica gel chromatography or the like, and can be used in the next reaction after separation. When R ₄ is a lower alkyl group,
As shown in the following chemical structural formula (Formula 6), there are four types of diastereomers. Of these, the α and β anomers can be separated by silica gel chromatography or the like, and can be used in the next reaction after separation.

[0012]

[Chemical 6] The compound of general formula (I) can be prepared by the process B according to general formula (II)
The compound of n-hexane, nitrobenzene, chlorobenzene, methylene chloride, chloroform, carbon tetrachloride, 1,
Lewis acid such as tin tetrachloride, titanium tetrachloride, aluminum chloride, ferric chloride, boron trifluoride diethyl ether complex or sulfuric acid, nitric acid, hydrochloric acid, in an inert solvent such as 2-dichloroethane, carbon disulfide, acetonitrile and the like. It can be obtained by an intramolecular cyclization reaction in the presence of a mineral acid such as chlorosulfonic acid, phosphoric acid, benzenesulfonic acid, trifluoromethanesulfonic acid or an organic acid. Reaction temperature is -7
The temperature can be from 0 ° C. to the boiling point of the solvent, but it is advantageous to carry out the reaction in a relatively low temperature range, and a suitable temperature is −70 ° C. to 30 ° C. After completion of the reaction, post-treatment is carried out in the usual way, and the desired compound can be obtained by recrystallization or purification by column chromatography. The compound of the general formula (I) obtained here is a single optically active substance when R ₄ is a hydrogen atom, but when R ₄ is a lower alkyl group, the two diastereomers represented by the following chemical structural formula (Formula 7) Obtained as.

[0013]

[Chemical 7] This diastereomeric mixture can be separated by silica gel chromatography or the like, and both compounds have high herbicidal activity. It is also possible to obtain a desired single optically active substance by using the optically active compound of the general formula (II). To obtain the optically active compound of general formula (II), for example, by reacting the optically active compound of general formula (IV) in step (A).

When R ₄ is a lower alkyl group, the resulting 2
The diastereomers of the species are separated by silica gel chromatography and subjected to silica gel chromatography (developing solvent;
The diastereomer eluted first with n-hexane: ethyl acetate was referred to as the compound (general formula (I) -A), and the diastereomer eluted later was referred to as the compound (general formula (I) -B).
¹ H-NMR of the compound represented by the general formula (I) is shown in Table 2, and the diastereomers (general formula (I) -A) and (general formula (I) -B) have the 5-position. Classification is possible from the assignment of the protons of. For example, when R ₄ is a methyl group,
The 5-position proton is a diastereomer (general formula (I)-
A) is observed around 4.6 ppm, and (general formula (I) -B) is observed around 5.0 ppm. As described above, the diastereomers (general formula (I) -A) and (general formula (I) -B) both have herbicidal activity.

Another method of synthesizing the compound of the general formula (I) is to introduce or convert a new substituent into the furobenzopyran derivative obtained by the intramolecular cyclization reaction. The introduction or conversion of the substituent used here can be carried out by a well-known organic synthesis method. The reaction formulas 2 and 3 that are one example thereof will be described below.

Reaction formula 2 is an example of introduction when the substituent R ₅ is an amino derivative. For example, the compound of the general formula (VI) can be obtained by subjecting the compound of the general formula (V) obtained by the intramolecular cyclization reaction to an ordinary nitration reaction using a mixed acid of nitric acid and sulfuric acid in the step (C). Then, the compound of the general formula (VII) in which the substituent R ₅ is an amino group can be obtained by subjecting the compound of the general formula (VI) to a reduction reaction such as a hydrogenation reaction under atmospheric pressure in the step (D). General formula (VII
The compound of I) can be easily obtained by reacting the compound of the general formula (VII) with a lower alkyl halide or acid chloride in the presence of an organic or inorganic base in an inert solvent according to the step (E).

In the reaction formula 3, the substituent R_Five Carboxylic acid
An example of introducing a substituent in the case of a conductor is shown. For example, the general formula
The compound (X) is substituted by an intramolecular cyclization reaction.
Group R ₃ Of the general formula (IX) in which one of the groups is a chloromethyl group
The compound was treated with sodium chloride in an inert solvent according to step (F).
React with 2-nitropropane in the presence of a base such as toxide
It is obtained by Compounds of general formula (XI) are
The compound of the general formula (X) is treated with chromic acid or peracid according to step (G).
It can be obtained by carrying out an oxidation reaction using hydrogen chloride or the like.
The compound of the general formula (XII) can be prepared according to the general formula by the step (H).
The compound of (X) is dehydrated with an amine derivative in an inert solvent.
It is obtained by taking action. General formula (XIII)
The compound is prepared by reacting the compound of the general formula (XI) by the step (J).
Use onyl chloride etc. to make acid chloride, or
Activate the carbonyl group using lubonyldiimidazole, etc.
Activated intermediates and inorganic or organic bases in an inert solvent
Obtained by reacting with an amine derivative in the presence of
It In the compound of the general formula (XIII), X is a sulfur atom.
In the case of, use a compound in which X is an oxygen atom, such as Lawesson's reagent
It can be easily obtained by reacting.

All of the compounds A, B and C according to the present invention are known compounds and are disclosed in JP-A-50-126830, JP-A-54-41872 and JP-A-57-7, respectively.
Further, the compound A is commercially available as a general name pyrazolate, the compound B is pyrazoxifene, and the compound C is commercially available as benzophenap. Further, all of the compounds D, E and F according to the present invention are known compounds, and are disclosed in JP-A-55-43014, JP-B-48-35454, JP-A-60-172910, etc., respectively. Further, the compound group represented by the general formula (I), which is commercially available as a general name of bromobutide as compound D and as compound E as dimuron, has excellent activity as a herbicide for paddy fields, and particularly, millet and eel. , High activity for annual broad-leaved weeds, but low for perennial weeds such as Urikawa. On the other hand, compounds A, B, and C are known as herbicides having a high effect on broad-leaved weeds such as Urikawa, but they have a low effect on fly and a large application amount. Also compound D,
E and F are known to be highly effective herbicides for Cyperaceae weeds such as firefly, but they have a low effect on millet and broad-leaved weeds, and their application amount is relatively large.

As described above, the compound group represented by the general formula (I), the pyrazole derivative, and the compounds D, E, and F may not be expected to have sufficiently satisfactory herbicidal effects when they are used alone. When mixed seeds are used, it may not be possible to expect sufficient effects on weeds that have grown.

The inventors of the present invention have studied the mixed use of the compound of the general formula (I), the pyrazole derivative and the compound selected from the compounds D, E and F, and found that a synergistic effect which was initially unpredictable was obtained. As a result, we found a herbicidal composition capable of controlling important weeds in paddy fields accurately, with a wide range of suitable treatment periods, and using them in much smaller amounts than when used alone or as a mixture of two kinds, without damaging the paddy fields. It was

The herbicide composition according to the present invention thus obtained may be used as it is for the plant to be treated, but it is generally mixed with an inert liquid or solid,
It is used after being adjusted to a commonly used formulation form such as powder, granules, wettable powder, emulsion, flowable formulation and the like. Further, an auxiliary agent can be added if necessary for formulation.

The carrier may be either solid or liquid as long as it is usually used for agricultural and horticultural chemicals, and is not limited to a specific one. For example, solid carriers include mineral powders such as clay, talc, bentonite, calcium carbonate, diatomaceous earth and white carbon, plant powders such as soybean powder and starch, petroleum resins, polyvinyl alcohol, polyalkylene glycols and the like. Examples include molecular compounds, urea, waxes and the like. Examples of the liquid carrier include various oils, various organic solvents, water and the like.

As the auxiliaries, surfactants, binders, stabilizers and the like which are usually used in agricultural and horticultural chemicals can be used alone or in combination as required. Further, in some cases, an industrial bactericidal agent or an antibacterial / antifungal agent may be added for antibacterial / antifungal purposes.

As the surfactant, nonionic, anionic, cationic and amphoteric surfactants can be appropriately used. Preferred examples include alkylphenols, higher alcohols, alkylnaphthols, higher fatty acids, fatty acid esters, dialkylphosphate amines and the like obtained by polymerizing ethylene oxide and propylene oxide, alkyl sulfate ester salts (sodium lauryl sulfate, etc.), alkyl sulfonates. (Eg, sodium 2-ethylhexene sulfonate) and aryl sulfonates (sodium ligninsulfonate, sodium dodecylbenzenesulfonate, etc.).

An excellent herbicidal effect can be expected in a wide range of the mixing ratio of the furobenzopyran derivative represented by the general formula (I), which is a component contained in the herbicidal composition according to the present invention, and the compounds A, B and C. However, the mixing ratio of the two is usually 1 part by weight of the furobenzopyran derivative to the compounds A, B and C.
Each is 0.5 to 100 parts by weight, preferably 1 to 50 parts by weight of each of the compounds A, B and C with respect to 1 part by weight of the furobenzopyran derivative.

The furobenzopyran derivative represented by the general formula (I), which is a component contained in the herbicidal composition according to the present invention, and the pyrazole derivative, and the compounds D, E and F are mixed in a wide range of excellent herbicidal effects. Can be expected. But 3
The mixing ratio of the above is usually 0.5 to 500 parts by weight of the pyrazole derivative, 0.5 to 500 parts by weight of each of the compounds D, E, and F, preferably 1 part by weight of the furobenzopyran derivative, relative to 1 part by weight of the furobenzopyran derivative. 1 to 100 parts by weight of the pyrazole derivative, 1 each of the compounds D, E and F
˜50 parts by weight.

The herbicidal composition according to the present invention is effective in all treatment methods such as flooded soil treatment, soil treatment, soil mixed layer treatment, and foliar spray treatment, but use in flooded soil treatment is preferred. The amount of the mixture is 0.001 kg
It is possible to use in a wide range from 1 to 50 kg / ha, but it is preferable to use in a range of 0.01 kg to 5 kg / ha as a standard.

The herbicidal composition according to the present invention can be used in combination with one or more kinds of other herbicides, pesticides such as insecticides and plant growth regulators, soil improvers or fertilizers. Not to mention, it is also possible to prepare a mixed preparation with these, and in some cases, a synergistic effect can be expected.

[0029]

EXAMPLES Next, the present invention will be described in more detail by way of examples. First, a production example of a novel compound represented by the general formula (I) will be described as a reference example. Reference Example 1 (2R, 3S, 3aS, 9bR) -2-Ethyl-6-methoxymethyl-3- (2-methylbenzyloxy)-
3,3a, 5,9b-tetrahydro-2H-furo [3,3
Preparation of 2-c] [2] benzopyran (Compound No. 1) 1) Methyl 5-deoxy-5-C-methyl-3-O-
Preparation of (2-methylbenzyl) -D-xylofuranoside 5-deoxy-1,2-O-isopropylidene-5-C
-Methyl-3-O- (2-methylbenzyl) -α-D-
70.97 g of xylofuranose was added to methanol (300 m
0.5 g of p-toluenesulfonic acid after dissolution in 1)
Was added and the mixture was heated under reflux for 10 hours. After allowing to cool, the reaction solution was neutralized with an aqueous sodium hydrogen carbonate solution, and the solvent was evaporated under reduced pressure.
This was added to water, extracted with a mixed solvent of ether and ethyl acetate (1: 1), and then the organic layer was washed with water. This was dried over anhydrous sodium sulfate, and the solvent was distilled off under reduced pressure to obtain an oily crude product. This was purified by silica gel chromatography (developing solvent; n-hexane: ethyl acetate = 3: 1) to obtain 64.21 g of the target compound as an anomeric mixture of α-form and β-form. (Yield 99.2%) 2) Preparation of methyl 5-deoxy-2-O- (2-methoxymethylbenzyl) -5-C-methyl-3-O- (2-methylbenzyl) -D-xylofuranoside 1 ) Methyl 5-deoxy-5-C-methyl-3-O- (2
-Methylbenzyl) -D-xylofuranoside 25.0 g
Was dissolved in 200 ml of tetrahydrofuran and 4.44 g of oily sodium hydride (40% liquid paraffin) was added with stirring.
Content) was gradually added. To this, tetrabutylammonium iodide (1.0 g) and (2-methoxymethyl) benzyl bromide (22.2 g) were added, and the mixture was stirred at room temperature for 4 hours. After adding a small amount of water under ice cooling, the solvent was distilled off under reduced pressure, and the obtained crude product was added to water and extracted with ether. The organic layer was thoroughly washed with water, dried over anhydrous sodium sulfate, and the solvent was distilled off under reduced pressure to obtain an oily crude product. The crude product was purified by silica gel chromatography (developing solvent; n-hexane: ethyl acetate = 10: 1) to obtain the target compound 3
4.7 g was obtained as an anomeric mixture of α-form and β-form. (Yield 92.4%) 3) (2R, 3S, 3aS, 9bR) -2-ethyl-6
-Methoxymethyl-3- (2-methylbenzyloxy)
Preparation of 3,3a, 5,9b-tetrahydro-2H-furo [3,2-c] [2] benzopyran Methyl 5-deoxy-2-O- obtained by 2)
(2-Methoxymethylbenzyl) -5-C-methyl-3
0.62 g of -O- (2-methylbenzyl) -D-xylofuranoside (a mixture of α and β isomers) was added to 10 m of acetonitrile.
The resulting solution was dissolved in 1 and added with 4.97 ml of tin tetrachloride (1.0 M dichloromethane solution) under ice cooling. This was stirred at room temperature for 3 hours and then poured into a saturated aqueous sodium hydrogen carbonate solution containing ice. The organic layer was thoroughly washed with water, dried over anhydrous sodium sulfate, and the solvent was distilled off under reduced pressure to obtain an oily crude product. The crude product was purified by silica gel chromatography (developing solvent; n-hexane: ethyl acetate = 5: 1) to obtain 0.56 g of the target compound (yield 98.5%).

Reference Example 2 (2R, 3S, 3aS, 9bR) -2-Ethyl-3-
(2-Methylbenzyloxy) -6-formyl-3,3
a, 5,9b-Tetrahydro-2H-furo [3,2-
Preparation of c] [2] benzopyran (Compound No. 2) 1) Methyl 2-O- (2-chloromethylbenzyl)-
Production of 5-deoxy-5-C-methyl-3-O- (2-methylbenzyl) -D-xylofuranoside Methyl 5-deoxy-5-C-methyl-3 obtained in 1) of Reference Example 1
2.5 g of -O- (2-methylbenzyl) -D-xylofuranoside was dissolved in 15 ml of dimethylformamide, and 0.44 g of sodium hydroxide was added with stirring. To this, 1.81 g of α, α'-dichloro-o-xylene was added,
The mixture was stirred at 40 ° C for 5 hours. The crude product obtained by performing the same post-treatment as in 2) of Reference Example 1 was subjected to silica gel chromatography (developing solvent; n-hexane: ethyl acetate =).
10: 1) and purify the target compound with 3.50 g
Obtained as an anomeric mixture of body and beta form. (Yield 9
2.0%) 2) (2R, 3S, 3aS, 9bR) -2-ethyl-3
-(2-Methylbenzyloxy) -6-chloromethyl-
3,3a, 5,9b-tetrahydro-2H-furo [3,3
Preparation of 2-c] [2] benzopyran Methyl 2-O- (2-chloromethylbenzyl) -5-deoxy-5-C-methyl-3-obtained by 1)
1.02 g of O- (2-methylbenzyl) -D-xylofuranoside was dissolved in 12 ml of chloroform and titanium tetrachloride (1.0 M dichloromethane solution) 8.17 m under ice cooling.
1 was added. This was stirred at room temperature for 2 hours and then poured into a saturated aqueous sodium hydrogen carbonate solution containing ice. The organic layer was thoroughly washed with water, dried over anhydrous sodium sulfate, and the solvent was distilled off under reduced pressure to obtain an oily crude product. The crude product was subjected to silica gel chromatography (developing solvent; n-hexane:
Purification with ethyl acetate = 5: 1) gave the desired compound 1.
00g was obtained. (Yield 97.6%) 3) (2R, 3S, 3aS, 9bR) -2-ethyl-3
-(2-methylbenzyloxy) -6-formyl-3,
3a, 5,9b-tetrahydro-2H-furo [3,2-
Preparation of c] [2] benzopyran (Compound No. 2) 0.4 g of 2-nitropropane in methanol (15 m
0.82 g of sodium methoxide was added to l) under ice cooling, and the mixture was stirred at room temperature for 30 minutes and then obtained in 2) (2R, 3).
S, 3aS, 9bR) -2-Ethyl-6-chloromethyl-3- (2-methylbenzyloxy) -3,3a, 5
9b-Tetrahydro-2H-furo [3,2-c] [2]
A solution of 1.5 g of benzopyran in methanol (15 ml) was added and the mixture was refluxed for 3 hours. The reaction solution was concentrated under reduced pressure, water was added to the obtained residue, and the mixture was extracted with dichloromethane. The organic layer was thoroughly washed with water, dried over anhydrous sodium sulfate, and the solvent was distilled off under reduced pressure to obtain an oily crude product. The crude product was subjected to silica gel chromatography (developing solvent; n-hexane:
Purification was performed with ethyl acetate = 10: 1) to obtain 1.22 g (yield 87%) of the target compound.

Reference Example 3 (2R, 3S, 3aS, 9bR) -2-Ethyl-3-
(2-Methylbenzyloxy) -6- (1-hydroxyethyl) -3,3a, 5,9b-tetrahydro-2H-
Production of Furo [3,2-c] [2] benzopyran (Compound No. 3) Obtained by Reference Example 2 (2R, 3S, 3aS, 9b
R) -2-Ethyl-3- (2-methylbenzyloxy)
-6-formyl-3,3a, 5,9b-tetrahydro-
0.6 g of 2H-furo [3,2-c] [2] benzopyran
Was dissolved in tetrahydrofuran (10 ml), and 3.40 ml of methylmagnesium bromide (1.0 M tetrahydrofuran solution) was added dropwise under ice cooling. After stirring at room temperature for 1 hour, the mixture was poured into ice-cooled dilute hydrochloric acid and extracted with ethyl acetate. The organic layer was washed with water and then with a saturated aqueous sodium hydrogen carbonate solution, and then dried over anhydrous sodium sulfate. The solvent was distilled off under reduced pressure to obtain an oily crude product. The crude product was purified by silica gel chromatography (developing solvent; n-hexane: ethyl acetate = 5: 1) to obtain 0.48 g (yield 77.4%) of the target compound.

Other compounds represented by the general formula (I) according to the present invention were synthesized in the same manner as in Reference Examples 1 to 3.
These compounds are shown in Table 1 (Tables 1 to 9), and their physical properties are shown in Table 2 (Tables 10 to 28).

[0033]

[Table 1]

[0034]

[Table 2]

[0035]

[Table 3]

[0036]

[Table 4]

[0037]

[Table 5]

[0038]

[Table 6]

[0039]

[Table 7]

[0040]

[Table 8]

[0041]

[Table 9]

[0042]

[Table 10]

[0043]

[Table 11]

[0044]

[Table 12]

[0045]

[Table 13]

[0046]

[Table 14]

[0047]

[Table 15]

[0048]

[Table 16]

[0049]

[Table 17]

[0050]

[Table 18]

[0051]

[Table 19]

[0052]

[Table 20]

[0053]

[Table 21]

[0054]

[Table 22]

[0055]

[Table 23]

[0056]

[Table 24]

[0057]

[Table 25]

[0058]

[Table 26]

[0059]

[Table 27]

[0060]

[Table 28] Next, formulation examples and herbicidal activity test examples of the herbicidal composition of the present invention are shown.

Formulation Example 1 (wettable powder) Compound (1) of the present invention: 3 parts by weight, compound (A): 20 parts by weight, compound (D): 10 parts by weight, neoperex (trade name, manufactured by Kao; dodecyl) Sodium benzene sulfonate): 2 parts by weight, Neugen EA80 (trade name, manufactured by Dai-ichi Kogyo Seiyaku; polyoxyethylene nonylphenyl ether): 2 parts by weight, white carbon: 5 parts by weight and 58 parts by weight of diatomaceous earth are well pulverized and mixed. To obtain a wettable powder.

Formulation Example 2 (flowable agent) Compound (131) of the present invention: 2 parts by weight, Compound (B): 1
8 parts by weight, compound (E): 10 parts by weight, sodium lignin sulfonate: 3 parts by weight, and polyoxyethylene alkylaryl ether: 1 part by weight, water: 65.7.
After adding parts by weight and mixing and finely pulverizing with a sand grinder, xanthan gum: 0.3 parts by weight was added to obtain a flowable agent.

Formulation Example 3 (flowable agent) Compound (122) of the present invention: 5 parts by weight and compound (C): 1
5 parts by weight, compound (F): 15 parts by weight, sun extract P252 dissolved in 40 parts by weight of water (trade name, the same as above):
Kelzan S (trade name, manufactured by Kelco; xanthan gum) dissolved in 14.6 parts by weight of water after wet-grinding and mixing 10 parts by weight: 0.2 part by weight and Deltop (trade name, manufactured by Takeda Pharmaceutical Co., Ltd .: organic iodine) Antifungal agent: 0.2 part by weight was added and mixed to obtain a flowable agent.

Formulation Example 4 (powder) Compound (20) of the present invention: 1 part by weight, compound (A): 7 parts by weight, compound (D): 4 parts by weight, Emulgen 910 (trade name, manufactured by Kao; polyoxyethylene) Nonyl phenyl ether): 0.5 part by weight and kaolin clay: 87.5
Parts by weight were well pulverized and mixed to obtain a dust.

Formulation Example 5 (powder) Compound (135A) of the present invention: 2 parts by weight, Compound (C):
15 parts by weight, compound (D): 10 parts by weight, sodium ligninsulfonate: 3 parts by weight, polyoxyethylene alkylaryl ether: 2 parts by weight and clay: 68 parts by weight were mixed and pulverized to obtain a dust.

Formulation Example 6 (dry flowable agent) Finely ground compound (122) of the present invention: 2 parts by weight, compound (B): 20 parts by weight, compound (E): 10 parts by weight, sodium alkylbenzenesulfonate: 15 parts by weight And polypropylene glycol polyethylene glycol ether: 53 parts by weight were mixed to obtain a dry flowable agent.

Formulation Example 7 (granules) Compound (131) of the present invention: 2 parts by weight, Compound (C): 1
5 parts by weight, compound (D): 10 parts by weight, neoperex (trade name, the same as above): 2 parts by weight, sun extract P25
2 (trade name, manufactured by Sanyo Kokusaku Pulp; sodium lignin sulfonate): 2 parts by weight, bentonite: 46 parts by weight and talc: 23 parts by weight, were mixed well, and then an appropriate amount of water was added to moisten it, and then it was laid horizontally. It was extruded and granulated by an extrusion granulator. This was air-dried at 30 to 60 ° C. and crushed, and then sized to 0.3 to 2 mm with a sizing machine to obtain a granule.

Formulation Example 8 (granules) 3 parts by weight of the compound (122) of the present invention, compound (C): 10
Parts by weight, compound (F): 20 parts by weight, gohsenol (G
Osenol) GL-05s (Nippon Gosei Kagaku PV
A): 2 parts by weight, Sun extract P252 (Sanyo Kokusaku Pulp Sodium Lignin Sulfonate): 2 parts by weight and clay: 63 parts by weight, were mixed well, then an appropriate amount of water was added to moisten, and then lateral extrusion was performed. It was extruded and granulated by a granulator.
This was air-dried at 60 to 90 ° C. and crushed, and then crushed with a sieving machine.
Granules were obtained by sizing to 3 to 1 mm.

Formulation Example 9 (Emulsion) Inventive compound (135-A): 2 parts by weight, compound (B): 5 parts by weight, compound (D): 10 parts by weight, Solpol 800A (trade name, manufactured by Toho Kagaku; A mixture of a nonionic surfactant and an anionic surfactant): 10 parts by weight and o-xylene: 73 parts by weight were mixed and dissolved to obtain an emulsion.

Test Example 1 Flooded Soil Treatment Test (Pre-Emergence Treatment) 1/5000 arell grennel pots were filled with soil, and seeds or tubers of rice barley, eel, firefly, Urikawa were sown to make a waterlogged state. Two paddy rice seedlings (2 to 3 leaf stage) that had been raised in advance were used as one strain, and the two strains were transplanted and grown in a greenhouse. 1 day later (before weed emergence),
A predetermined amount of the test composition was treated with the granules prepared according to the method described in Formulation Example 7 above, and after 30 days, the occurrence of weeds and the damage to paddy rice were observed and investigated. The results are shown in Table 3 (Tables 29 to 32). In the table, the degree of damage to the test plant and the degree of phytotoxicity to the crop are shown based on the following criteria in comparison with the case where the growth state of the plant is untreated.

[0071]

[Table 29]

[0072]

[Table 30]

[0073]

[Table 31]

[0074]

[Table 32]

Test Example 2 Flooded Soil Treatment Test (Growth Stage Treatment) The soil was filled in a 1/5000 arengren pot, and seeds or tubers of the rice barley, eel, firefly, and urikawa were sown to make a flooded state. Two paddy rice seedlings (2 to 3 leaf stage) that had been raised in advance were used as one strain, and the two strains were transplanted and grown in a greenhouse. When the leaf was 2.5 leaves, a predetermined amount of the test composition was treated with the granules prepared according to the method described in Formulation Example 7 above, and after 30 days, the occurrence of weeds and rice paddy were treated. Observed and investigated the chemical damage situation. The results are shown in Table 4 (Tables 33 to 36). In the table, the degree of damage to the test plant and the degree of phytotoxicity to the crop are shown in the same manner as in Test Example 1.

[0076]

[Table 33]

[0077]

[Table 34]

[0078]

[Table 35]

[0079]

[Table 36]

[0080]

The herbicidal composition of the present invention has the general formula (I)
In comparison with the herbicidal effect of each of the furobenzopyran derivative, the pyrazole derivative, the compounds D, E, and F, which are used alone or when two kinds of them are mixed and used, because of extremely high synergism, a lower dose is used. It is also possible to exert a high effect on important weeds that have grown further. As a result, the herbicidal composition of the present invention has a wide suitable treatment period, can control important weeds in paddy fields accurately for a long period of time, has high applicability as a paddy field herbicide, and is extremely useful.

─────────────────────────────────────────────────── ─── Continuation of the front page (51) Int.Cl. ⁶ Identification code Office reference number FI technical display area A01N 37:18) (A01N 43/90 43:56 47:28) (A01N 43/90 43:56) 47:30) (72) Inventor Kiyoshi Arai, 1144 Togo, Mobara-shi, Chiba Mitsui Toatsu Chemical Co., Ltd. (72) Inventor Fumiaki Koizumi 1144, Togo, Mobara-shi, Chiba Mitsui Toatsu Chemical Co., Ltd.

Claims (1)

[Claims] 1. General formula (I) (Chemical formula 1) [In the formula, R ₁ represents a lower alkyl group, R ₂ represents a lower alkyl group, a lower alkoxy group, a halogen atom or a halogen-substituted lower alkyl group, and R ₃ represents a lower alkyl group, a lower alkoxy group, a halogen atom, a halogen-substituted group. Represents a lower alkyl group, a phenoxy group or a benzyloxy group,
R ₄ represents a hydrogen atom or a lower alkyl group, R ₅ is a cyano group, a nitro group, a phenyl group, group -S (O) _q R _6, group -0S0 ₂ R _6, group -XC (= O) R ₆ , A group-XR ₇ , a group-
_{XCH (R 9) C (=} O) R 8, group -XP (= X) (XR
₆ ) ₂ , group -N (R ₉ ) R ₁₀ , group -N (R ₉ ) C (= X) R
_11, group _{-N (R 9) SO 2 R} 6, group _{-C (R 9) 2 OR 10} ,
Group _{-CH (R 9) S (O} ) q R 6, group -CH (R ₉₎ XC
(= 0) R ₁₁ , group —CH (R ₉ ) N (R ₉ ) R ₁₀ , group —C
_{H (R 9) N (R} 9) C (= X) R 11, group -CH (R _{9)
XP (= X) (XR 6} ) 2, group -C (= X) R _8, group -C
H (XR ₁₂₎ XR _13, group -C (= X) N (R 14) R 15,
Group -CH = NR _8, group -CH = CR ₁₆ R _17, group -O {C
_{(R 18) 2} r -O-} ( by connecting the adjoining carbon atoms on the benzene ring forms a 5 or 6-membered ring) or a group - {C
(R ₁₈ ) ₂ } _s — (bonding adjacent carbon atoms on a benzene ring to form a 5- or 6-membered ring), wherein R ₆ is a lower alkyl group or (lower alkyl group, lower alkoxy). Group, which may be substituted with a halogen atom), a phenyl group, R ₇ represents a hydrogen atom, a halogen-substituted lower alkyl group or an alkoxyalkyl group, and R ₈ represents a hydrogen atom, a hydroxy group, a lower alkyl group, a lower alkoxy group. , A lower alkylthio group or a phenoxy group, R ₉ represents a hydrogen atom or a lower alkyl group, R ₁₀ represents a hydrogen atom, a lower alkyl group, a halogen-substituted lower alkyl group or an aralkyl group, and R ₁₁ represents a lower alkyl group, Halogen-substituted lower alkyl group, (lower alkyl group, lower alkoxy group, optionally substituted by halogen atom) phenyl group, lower alkoxy group, phenyl group Represents a phenoxy group, lower alkylamino group or anilino group, R _12, R ₁₃ is a hydrogen atom or a lower alkyl group or R ₁₂ and R ₁₃ are each cyclized together - (CH _{2) 2} - or - (CH ₂ ) represents _3-
R ₁₄ represents a hydrogen atom or a lower alkyl group, R ₁₅ represents a hydrogen atom, a lower alkyl group, a phenyl group (which may be substituted with a lower alkyl group, a lower alkoxy group, a halogen atom) or R ₁₄ and R ₁₅ are the same. Represents a 5- or 6-membered ring which may contain an oxygen atom, a sulfur atom or a nitrogen atom, R ₁₆ represents a hydrogen atom, a cyano group or a lower alkoxycarbonyl group, and R ₁₇ represents a hydrogen atom or a lower alkyl group. ,
Represents a nitro group, a cyano group or a lower alkoxycarbonyl group, R ₁₈ represents a hydrogen atom, a lower alkyl group or a halogen atom, X represents an oxygen atom or a sulfur atom, q
Is an integer of 0 to 2, r is 1 or 2, s is 3 or 4
Represents } M is an integer of 0-4, n is an integer of 0-2, and p is 1-3.
When m, n and p are 2 or more, R ₂ , R
₃ and R ₅ may be the same or different. ] At least 1 sort (s) or more of the furo benzo pyran derivative represented by these, and 4- (2,4- dichloro benzoyl)-
1,3-Dimethylpyrazol-5-yl-p-toluenesulfonate, 1,3-dimethyl-4- (2,4, -dichlorobenzoyl) -5-phenacyloxypyrazole and 1,3-dimethyl-4- ( 2,4-dichloro-3
-Methylbenzoyl) -5- (4-methylphenacyloxy) pyrazole and at least one or more pyrazole derivatives, and further 2-bromo-N- (α, α-
Dimethylbenzyl) -3,3-dimethylbutyramide, 1- (α, α-dimethylbenzyl) -3- (4-methylphenyl) urea and 1- (α, α-dimethylbenzyl) -3- (2-chlorobenzyl) ) A herbicide composition for paddy fields containing at least one selected from urea as an active ingredient.