JP2000109461A - Phenoxypyridine-based compound, its production and herbicide containing the same - Google Patents

Abstract

PROBLEM TO BE SOLVED: To produce the subject new compound having a chainlike group or a cycloalkyl group substituted at the 6-position of the pyridine ring and useful as an active ingredient of a herbicide. SOLUTION: This compound is represented by formula I [R1 is a halogen, a (halo-, alkoxy- or cyano) alkyl, a (halo- or alkoxy) alkoxy or the like; R2 is H, a (substituted) alkyl, a (substituted) cycloalkyl or the like; X is O or sulfur; (n) is 0-3], e.g. 2-(3-trifluoromethylphenoxy)-6-hydroxy-4-methoxypyridine. The compound represented by formula I in which R2 is H is obtained by carrying out a hydrolytic reaction of a compound represented by formula II [Bn is an (alkyl or alkoxy-substituted) benzyl] in the presence of an acid or a base. Furthermore, the resultant compound is then reacted with a compound represented by the formula: Z1-R2' [R2' is a (substituted) alkyl or the like; Z1 is a halogen] usually in the presence of a base to thereby afford the compound represented by formula I in which R2 is substituted.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

TECHNICAL FIELD The present invention relates to a novel phenoxypyridine compound useful as an active ingredient of a herbicide.

[0002]

2. Description of the Related Art JP-A-8-268808 describes a phenoxypyridine in which phenoxy or benzyloxy is substituted at the 6-position of a pyridine ring. However, the phenoxypyridine compound of the present invention is clearly distinguished from the phenoxypyridine compound in that a chain group or a cycloalkyl group is substituted at the 6-position of the pyridine ring.

[0003]

DISCLOSURE OF THE INVENTION Problems to be Solved by the Invention The present inventors have conducted various studies on phenoxypyridine compounds in order to find a better herbicide, and as a result, completed the present invention. That is, the present invention has the formula (I):

[0004]

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Wherein R ₁ is halogen, alkyl, haloalkyl, alkoxyalkyl, cyanoalkyl, alkoxy, haloalkoxy, alkoxyalkoxy, alkylthio, haloalkylthio, alkenyl, alkynyl, amino, monoalkylamino, dialkylamino,
Alkylsulfinyl, alkylsulfonyl, alkoxycarbonyl, dialkylaminocarbonyl, cyano or nitro, wherein R ₂ is a hydrogen atom, an optionally substituted alkyl, an optionally substituted alkenyl, an optionally substituted alkynyl or an optionally substituted X is an oxygen atom or a sulfur atom, n is an integer of 0 to 3, and when n is 2 or more, R ₁ may be the same or different. The present invention relates to a phenoxypyridine-based compound or a salt thereof, a method for producing the same, a herbicide containing them, and a novel intermediate compound for producing the same.

The substituents of the optionally substituted alkyl in R ₂ include halogen, C1-4 alkoxy, C1
-4 alkylthio, C3-6 cycloalkyl, amino,
C1-4 monoalkylamino, C1-4 dialkylamino, cyano, nitro and the like. The number of substitutions may be one or more, and when two or more, these substituents may be the same or different. The substituent may be substituted at any position.

The substituent of the optionally substituted alkenyl or the optionally substituted alkynyl in R ₂ includes halogen, C1-4 alkoxy, C1-4 alkylthio and the like. The number of substitutions may be 1 or 2 or more.
In the above case, these substituents may be the same or different. The substituent may be substituted at any position.

The substituent of the optionally substituted cycloalkyl in R ₂ includes halogen, C1-4 alkyl and the like. The number of substitutions may be 1 or 2 or more.
In the above case, these substituents may be the same or different. The substituent may be substituted at any position.

The alkyl and the alkyl moiety in R ₁ are C1
Straight-chain or branched, and alkyl and the alkyl moiety in R ₂ are C1-6 straight-chain or branched. Specific examples thereof include methyl, ethyl, propyl, isopropyl, butyl, tert-butyl, pentyl,
Hexyl and the like. Alkenyl and alkynyl in R ₁ are C2-4 linear or branched, and alkenyl, alkynyl, alkenyl and alkynyl in R ₂ are C2-6 linear or branched. is there.
Specific examples thereof include vinyl, allyl, isopropenyl, butadienyl, ethynyl, propargyl and the like.

The cycloalkyl in R ₂ is C3-6. Specific examples thereof include cyclopropyl, cyclobutyl, cyclohexyl and the like. The halogen in R ₁ and R ₂ or the halogen as a substituent is each atom of fluorine, chlorine, bromine or iodine. The number of halogens as a substituent may be 1 or 2 or more, and in the case of 2 or more, each halogen may be the same or different. Also,
The halogen may be substituted at any position.

The phenoxypyridine compound represented by the above formula (I) can form a salt. Examples of the salt include any salt that is agriculturally acceptable, and examples thereof include inorganic acid salts such as hydrochloride, sulfate, and nitrate; organic acid salts such as acetate and methanesulfonate; Alkali metal salts such as sodium salt and potassium salt; alkaline earth metal salts such as magnesium salt and calcium salt; and ammonium salts such as dimethylamine salt and triethylamine salt.

The phenoxypyridine-based compound represented by the above formula (I) or a salt thereof (hereinafter abbreviated as the compound of the present invention) can be produced according to the following reactions [A] to [D] and an ordinary method for producing a salt.

[0013]

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In the reaction [A], R ₁ , X and n are as described above, and Bn is benzyl which may be substituted by alkyl or alkoxy. Reaction [A] is a hydrolysis reaction performed in the presence of an acid or a base. As the acid, one or more kinds can be appropriately selected from, for example, inorganic acids such as hydrochloric acid and sulfuric acid; and organic acids such as acetic acid. Examples of the base include one or two of a carbonate such as sodium carbonate and potassium carbonate; a bicarbonate such as sodium bicarbonate and potassium bicarbonate; and a metal hydroxide such as sodium hydroxide and potassium hydroxide. More than one species can be appropriately selected.

The reaction [A] is carried out in the presence of a solvent, if necessary. As the solvent, any solvent may be used as long as it is inert to the reaction, for example, benzene, toluene,
Aromatic hydrocarbons such as xylene and chlorobenzene;
Cyclic or acyclic aliphatic hydrocarbons such as carbon tetrachloride, methyl chloride, chloroform, dichloromethane, dichloroethane, trichloroethane, hexane, and cyclohexane; ethers such as dioxane, tetrahydrofuran, and diethyl ether; such as methyl acetate and ethyl acetate Ester; polar aprotic solvent such as dimethyl sulfoxide, sulfolane, dimethylacetamide, dimethylformamide, N-methylpyrrolidone, pyridine; nitrile such as acetonitrile, propionitrile, acrylonitrile; ketone such as acetone, methyl ethyl ketone Alcohols such as methanol, ethanol, propanol and tert-butanol; one or more of water and the like can be appropriately selected. Reaction [A]
Is usually -10 to + 200 ° C, desirably 10 to 100 ° C, and the reaction time is usually 0.5 to 24.
Hours, preferably 1 to 18 hours.

The reaction [A] is a reaction in which X in the formula (I-1) is an oxygen atom, and is a hydrogenation reaction carried out in the presence of a catalyst. As the catalyst, for example, one or two or more of palladium, palladium carbon, palladium chloride, iron, platinum, other palladium-based catalysts used in the field, platinum-based catalysts, and the like can be appropriately selected.
The catalyst is usually used in a catalytic amount, but may be used in an excessive amount depending on the type of R ₁ which is a substituent on the pyridine ring.

The reaction [A] is usually carried out in the presence of a solvent. The solvent may be any solvent as long as it is inert to the reaction, for example, aromatic hydrocarbons such as benzene, toluene and xylene; esters such as methyl acetate and ethyl acetate; acetonitrile and propionitrile , Nitriles such as acrylonitrile; amines such as monomethylamine, dimethylamine, triethylamine; methanol, ethanol, propanol, tert
One or two of alcohols such as butanol;
More than one species can be appropriately selected. The reaction temperature of the reaction (A) is
The reaction temperature is usually -10 to + 200C, preferably 10 to 60C, and the reaction time is generally 0.5 to 48 hours, preferably 1 to 60 hours.
~ 24 hours.

The reaction [A] is a reaction wherein X in the formula (I-1) is an oxygen atom and Bn is benzyl substituted with alkoxy, and the debenzylation is carried out in the presence of an oxidizing agent. It is a reaction. The oxidizing agent can be appropriately selected from, for example, diammonium cerium (IV) nitrate, 2,3-dichloro-5,6-dicyano-para-benzoquinone, and the like.

The reaction [A] is usually performed in the presence of a solvent. The solvent may be any solvent as long as it is inert to the reaction, for example, aromatic hydrocarbons such as benzene, toluene, xylene, chlorobenzene; carbon tetrachloride, methyl chloride, chloroform, dichloromethane, dichloroethane, trichloroethane. And cyclic or non-cyclic aliphatic hydrocarbons such as hexane and cyclohexane; esters such as methyl acetate and ethyl acetate; polar non-cyclic hydrocarbons such as dimethyl sulfoxide, sulfolane, dimethylacetamide, dimethylformamide, N-methylpyrrolidone and pyridine. One or more can be appropriately selected from protic solvents; nitriles such as acetonitrile, propionitrile, and acrylonitrile; organic acids such as acetic acid and propionic acid; and water. The reaction temperature of the reaction [A] is usually -10 to + 140 ° C, preferably 0 to 80 ° C, and the reaction time is usually 0.1 to 24 hours, preferably 0.5 to 8 hours.

[0020]

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In the reaction (B), R ₁ , X, n and a compound represented by the formula (I-1)
Is as described above, and R ₂ ′ is an optionally substituted alkyl, an optionally substituted alkenyl, an optionally substituted alkynyl or an optionally substituted cycloalkyl,
Z ₁ and Z ₃ are each halogen. Reaction [B]
And are the same reaction conditions and can therefore be written as:

[0022]

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In the formula, R ₁ , R ₂ ′, n and the formula (I-2) are as described above, A is —XH (X is as described above) or halogen, and B is A is —XH When A is a halogen, it is -XH (X is as described above). Reaction [B] is usually performed in the presence of a base. As the base,
Alkali metals such as sodium and potassium; alcoholates of alkali metals such as sodium methylate, sodium ethylate and potassium tert-butylate; carbonates such as sodium carbonate and potassium carbonate; sodium bicarbonate and potassium bicarbonate A metal hydride such as sodium hydride and potassium hydride; an amine such as monomethylamine, dimethylamine and triethylamine; and a pyridine such as pyridine and 4-dimethylaminopyridine. Alternatively, two or more types can be appropriately selected.

The reaction [B] is performed in the presence of a solvent, if necessary. The solvent may be any solvent as long as it is inert to the reaction, for example, aromatic hydrocarbons such as benzene, toluene, and xylene; carbon tetrachloride, methyl chloride, chloroform, dichloromethane, dichloroethane, trichloroethane, and hexane. Cyclic or non-cyclic aliphatic hydrocarbons such as cyclohexane; ethers such as dioxane, tetrahydrofuran and diethyl ether; esters such as methyl acetate and ethyl acetate; dimethyl sulfoxide, sulfolane, dimethylacetamide, dimethylformamide, N Polar aprotic solvents such as methylpyrrolidone and pyridine; nitriles such as acetonitrile, propionitrile and acrylonitrile; ketones such as acetone and methyl ethyl ketone; monomethylamine, dimethyla Emissions, amines such as triethylamine; methanol, ethanol, propanol, tert- alcohols such as butanol; ammonia water; water one or more of such may be suitably selected.

The reaction [B] is carried out in the presence of a catalyst if necessary. As the catalyst, one or more of metal halides such as copper and iron, for example, copper iodide, copper chloride and the like can be appropriately selected. The reaction temperature of the reaction (B) is usually-
10 to + 200 ° C, preferably 10 to 150 ° C,
The reaction time is generally 0.01 to 48 hours, preferably 0.1 to 48 hours.
1 to 24 hours.

[0026]

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In the reaction (C), R ₁ , R ₂ ′, X, n and a compound represented by the formula
(I-2) is as described above, and Z ₂ is halogen. Other reaction conditions except the reaction time of the reaction [C] are the same as those in the reaction [B]. The reaction time of the reaction (C) is usually 1 to
168 hours, desirably 1-120 hours.

[0028]

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In the reaction [D], R ₁ , n and formula (IV) are as described above, and tert- is an abbreviation of tertiary. Reaction [D] is performed in the presence of a solvent, if necessary. The solvent may be any solvent as long as it is inert to the reaction, for example, aromatic hydrocarbons such as benzene, toluene, xylene, chlorobenzene; carbon tetrachloride, methyl chloride, chloroform, dichloromethane, dichloroethane, trichloroethane. Cyclic or non-cyclic aliphatic hydrocarbons such as hexane, cyclohexane; ethers such as dioxane, tetrahydrofuran and diethyl ether; esters such as methyl acetate and ethyl acetate; dimethyl sulfoxide, sulfolane, dimethylacetamide, dimethylformamide , N-methylpyrrolidone and pyridine; polar aprotic solvents such as acetonitrile, propionitrile and acrylonitrile; ketones such as acetone and methyl ethyl ketone; Organic acids such as phosphate, water, etc. from 1
The species or two or more species can be appropriately selected. The reaction temperature of the reaction [D] is usually 10 to 200 ° C, preferably 50 to 140 ° C.
The reaction time is generally 0.5 to 24 hours, preferably 1 to 6 hours.

The compound of the formula (II) used in the reaction [A] is a useful intermediate compound used in the present invention, and can be produced according to the production method of the following reaction [E].
New compounds are also included in the compounds of the formula (II).

[0031]

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In the reaction [E], R ₁ , X, n, Z ₂ ,
Z ₃ , Bn, Formula (II) and Formula (VII) are as described above.
Other reaction conditions except the reaction time of the reaction [E] are the same as those in the reaction [B]. The reaction time of the reaction [E] is usually 0.1 to 24 hours, preferably 0.5 to 5 hours. Other reaction conditions except the reaction time of the reaction [E] are the same as those in the reaction [B]. The reaction time of the reaction [E] is usually 1 to 168 hours, preferably 1 to 120 hours.

The compound of the formula (IV) used in the reaction [B] and [D] and the compound of the formula (V) used in the reaction [C]
The compound (I) is a useful intermediate compound used in the present invention, and can be produced according to the production method of the following reaction [F]. New compounds are also included in the compounds of the formulas (IV) and (VI).

[0034]

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In the reaction (F), the compounds represented by the formulas (IV), (V), (VI) and (VI)
I) and (IX) are as described above. Other reaction conditions except the reaction time of the reaction [F] are the same as those in the reaction [B]. The reaction time of the reaction [F] is usually 0.5 to 48 hours, preferably 1 to 24 hours. Reaction [F] is
The reaction is performed according to the above-mentioned reaction [B].

The compounds of the formula (IX) used in the reactions [E] and [F] are useful intermediate compounds used in the present invention. Or a compound that can be synthesized by an ordinary method with reference to various documents. As the above document, for example, JP-A-8-269055 (paragraphs 0030 to 0)
032 and Reference Production Examples 1-4) and J.I. Org. Ch
em. 1991, 56, 4793-4796, and the like.

The compound of the present invention and the intermediate compound for production have optical isomers depending on the type of the substituent (in the case of having a substituted cycloalkyl moiety). Both mixtures (racemic) are included. In the present specification, this optical isomer is described as a racemic form unless otherwise specified.
In the compound of the present invention, the compound in which R ₂ is a hydrogen atom has tautomers, and the present invention includes both isomers and isomer mixtures. Further, the compound of the present invention and the intermediate compound for production have geometrical isomers depending on the type of the substituent (in the case of having an alkenyl moiety). In the present invention, each isomer (E-form, Z-form) and isomer Both body mixtures are included.

The compound of the present invention exhibits an excellent herbicidal effect when used as an active ingredient of a herbicide. The applicable range is wide, such as paddy fields, upland fields, orchards, mulberry fields, and other agricultural land, and mountain forests, agricultural roads, grounds, and non-agricultural land such as factory sites. The application method can be appropriately selected from soil treatment and foliage treatment.

The compounds of the present invention include, for example, rice grasses, scrophularid grasses, scrophularid grasses, scrophularus, scrophulariformes, scrophulariformes, scrophulariformes, sarcophagia, scrophulariformes, spruce, oakgrass, oakgrass, oakgrass, oakgrass, oakwood , Cyperaceae weeds such as scorpiongrass, stag beetle, pine bye, kurogwaii, etc. In addition to weeds, Ichibai, Malva Asagao, Shiroza, American sika deer, Purslane, Aobuyu, Ao-geito, Ebisu-gusa, Dogwood, Sasa It can control harmful weeds such as broadleaf weeds such as loblollys, chickweeds, firgrass, cornflowers, pokeweed, ragweed, yamgra, bilberry, Korean duckweed, sarcophaga fir, enokigusa, and useful crops such as maize, soybean, and soybean. , Wheat, rice, barley, oat, sorghum, rape, sunflower, sugar beet, sugar cane,
It is effectively used in the case of selectively controlling harmful weeds in the cultivation of turf, peanuts, flax, tobacco, coffee and the like, or in the case of non-selectively controlling harmful weeds. In particular, the compound of the present invention is effectively used in the cultivation of corn, soybean, wheat, rice and the like, and particularly in the case of selectively controlling harmful weeds in soybean cultivation.

The compound of the present invention is usually mixed with various agricultural auxiliaries to prepare powders, granules, wettable powders, wettable powders, aqueous suspensions, oily suspensions, aqueous solvents, emulsions, tablets, capsules. It is formulated in the form of a herbicide and used as a herbicide, but it can be in any form commonly used in the art as long as it conforms to the purpose of the present invention. Auxiliaries used in the formulation include diatomaceous earth, slaked lime, calcium carbonate,
Talc, white carbon, kaolin, bentonite,
Solid carrier such as a mixture of kaolinite and sericite, clay, sodium carbonate, sodium bicarbonate, sodium sulfate, zeolite, starch; water, toluene, xylene, solvent naphtha, dioxane, acetone, isophorone, methyl isobutyl ketone, chlorobenzene, cyclohexane, dimethyl Solvents such as sulfoxide, dimethylformamide, N-methyl-2-pyrrolidone, and alcohol; fatty acid salts, benzoates, alkylsulfosuccinates, dialkylsulfosuccinates, polycarboxylates, alkyl sulfates,
Alkyl sulfate, alkyl aryl sulfate, alkyl diglycol ether sulfate, alcohol sulfate, alkyl sulfonate, alkyl aryl sulfonate, aryl sulfonate, lignin sulfonate,
Alkyl diphenyl ether disulfonate, polystyrene sulfonate, alkyl phosphate ester salt, alkyl aryl phosphate, styryl aryl phosphate, polyoxyethylene alkyl ether sulfate, polyoxyethylene alkyl aryl ether sulfate, polyoxyethylene Alkyl aryl ether sulfate, polyoxyethylene alkyl ether phosphate, polyoxyethylene alkyl aryl phosphate,
Anionic surfactants and spreading agents such as salts of naphthalenesulfonic acid formalin condensates; sorbitan fatty acid esters, glycerin fatty acid esters, fatty acid polyglycerides, fatty acid alcohol polyglycol ethers, acetylene glycol, acetylene alcohol, oxyalkylene blocks Polymer, polyoxyethylene alkyl ether, polyoxyethylene alkyl aryl ether, polyoxyethylene styryl aryl ether, polyoxyethylene glycol alkyl ether, polyoxyethylene fatty acid ester, polyoxyethylene sorbitan fatty acid ester, polyoxyethylene glycerin fatty acid ester, poly Nonionic surfactants such as oxyethylene hydrogenated castor oil and polyoxypropylene fatty acid esters Vegetable oils such as olive oil, kapok oil, castor oil, palm oil, camellia oil, coconut oil, sesame oil, corn oil, rice bran oil, peanut oil, cottonseed oil, soybean oil, rapeseed oil, linseed oil, cutting oil, liquid paraffin, etc. Is mentioned. These adjuvants can be selected from those known in the art without departing from the purpose of the present invention. In addition, various commonly used auxiliary agents such as a bulking agent, a thickening agent, an anti-settling agent, an anti-freezing agent, a dispersion stabilizer, a safener, and a fungicide can be used.
The compounding ratio of the compound of the present invention and various auxiliaries is 0.1: 9.
9.9-95: 5, preferably 0.2: 99.8-8
5:15.

The application rate of the herbicide containing the compound of the present invention depends on weather conditions, soil conditions, formulation, type of target weed,
Although it cannot be specified unconditionally due to a difference in application time and the like, the compound of the present invention is generally 0.5 to 5000 per hectare.
g, preferably 1 to 1000 g, more preferably 5 to
Apply to 500 g. The present invention also includes a method for controlling harmful weeds by applying such a herbicide.

The herbicides containing the compound of the present invention include:
It can be mixed or used in combination with other pesticides, fertilizers, safeners and the like, and in this case, more excellent effects and effects may be exhibited. Other pesticides include herbicides, fungicides, antibiotics, plant hormones, insecticides, and the like. In particular, one or two active compound compounds of the compound of the present invention and another herbicide
The mixed herbicidal composition in which or more species are mixed or used in combination can improve the range of applied grass species, the timing of chemical treatment, the herbicidal activity and the like in a preferable direction. The compound of the present invention and the active ingredient compound of the other herbicides may be prepared separately and mixed at the time of spraying, or both may be prepared together and used. The present invention also includes the above-mentioned mixed herbicidal composition.

The mixing ratio of the compound of the present invention to the active ingredient compound of another herbicide cannot be specified unconditionally due to differences in weather conditions, soil conditions, formulation of the drug, application time, application method and the like. The other herbicides contain 0.001 to 10,000 parts by weight, preferably 0.01 to 1000 parts by weight, of the active ingredient compound per 1 part by weight.
The appropriate amount of application is 0.1 to 10000 g, preferably 0.2 to 5 g, as the total amount of the active ingredient compound per hectare.
000 g. The present invention also includes a method for controlling harmful weeds by applying such a mixed herbicidal composition.

As the active ingredient compounds of other herbicides, the following compounds (generic names) can be exemplified. Even when there is no particular description, if these compounds contain salts, alkyl esters, etc. They are included.

(1) 2,4-D, MCPA, MCPB,
Phenoxys, such as naproanilide, 2,3,6-TBA, dicamba
amba), picloram, aromatic carboxylic acids such as clopyralid, benzazolin, quinclorac, quinmerac, diflufenzopyr (di)
Flufenzopyr, which is said to exhibit herbicidal efficacy by disrupting the auxin action of plants.

(2) diuron, linuron, isoproturone (isop)
roturon), metobenzlon (metobenz)
urea such as uron, simazine
e), atrazine, atratone, simetryn
n), promethrin, dimethamethrin, metribuzine, terbutyrazine (ter)
butylazine), cyanazine (cyanaz)
ine), triazines such as ametrine, uracils such as bromacil, lenacil, propanil, cypromid
Anilides such as d), sweeps, carbamates such as phenmedipham, bromoxynini
l), bromoxynil octanoate (bromox)
ynil-octanoate), ioxynil (i
oxynil), such as hydroxybenzonitrile,
Others, such as pyridate and bentazone, which are said to exhibit herbicidal efficacy by inhibiting plant photosynthesis.

(3) Quaternary ammonium salts such as paraquat and diquat, which are themselves considered as free radicals in plants and generate active oxygen to exhibit a rapid herbicidal effect. system.

(4) Nitrophen
n), chloromethoxyphene
en), bifenox, acifluorfen sodium salt (acifluorfen-s)
odium), fomesafen (fomesafen),
Diphenyl ethers such as oxyfluorfen, lactofen, and chlorophthalim
m), flumioxazin (flumioxadin)
e), full micro rack pentyl (flumiclor)
ac-pentyl), furthiacet-methyl (flu)
cyclic imides such as thiacet-methyl, and other oxadiargyls
1), oxadiazon, sulfentrazone, carfentrazone-ethyl
thyl), thidiazimine (thidiazimi)
n), pentoxazone, azafenidin, pyraflufen-ethyl, flumioxazine, 5- [4-
Bromo-1-methyl-5- (trifluoromethyl) -1
H-pyrazol-3-yl] -2-chloro-4-fluorobenzoate inhibits chlorophyll biosynthesis in plants, and exhibits herbicidal efficacy by abnormally accumulating photosensitized peroxides in plants. What is said to be.

(5) norflurazone
zon), metflurazon (metflurazon)
Pyridazinones such as pyrazolates
late), pyrazoxyfen
n), pyrazoles such as benzofenap, and other fluridones
ne), flurtamone, diflufenican, methoxyphenone, clomazone, sulcotrione (sulc)
otrine, mesotrione
e), isoxaflutol
e), difenzoquat,
Isoxachlortol
As described in e) and the like, those which inhibit the pigment biosynthesis of plants such as carotenoids and exhibit herbicidal activity characterized by a whitening effect.

(6) Diclohopmethyl (diclof)
op-methyl), pyriphenop-sodium, fluazifop-butyl, haloxyfop-methyl
1), quizalofop-e
thyl), cyhalofop butyl (cyhalofop)
-Butyl), fenoxapropethyl (feno)
aryloxyphenoxypropionic acids such as xaprop-ethyl, alloxydim-sodium, clethodym, cetoxydim
ydim), tralkoxydim (tralkoxydi)
m), cyclohexanedione such as butroxydim, tepraloxydim, etc., whose herbicidal activity is strongly recognized specifically for grasses.

(7) Chlorimuron ethyl (chlori)
muron-ethyl), sulfometuron methyl (s
ulformuron-methyl, primisulfuron-methyl
yl), bensulfuron methyl (bensulfuro)
n-methyl), chlorsulfuron (chlors)
ulfuron), metsulfuron-methyl (metsu)
lfuron-methyl), sinosulfuron (ci)
nosulfuron), pyrazosulfuron-ethyl (p
irazosulfuron-ethyl, azimsulfuron, flazasulfuron, rimsulfuron, rimusulfuron, nicosulfuron (ni)
cosulfuron), imazosulfuron (imaz
osulfuron), cyclosulfamuron (cyc)
losulfamuron, prosulfuron (pro)
sulfuron), flupilsulfuron (flupy)
rsulfuron), trisulfuron-methyl (tri)
Sulfuron-methyl, halosulfuron-methyl, thifensulfuron-methyl
n-methyl), ethoxysulfuron (ethox)
ysulfuron), oxasulfuron (oxasu)
lfuron), full carbazon
one), such as sulfonylurea, flumetslam, metoslam
ulam), dicloslam,
Triazalopyrimidinesulfonamides such as chloranslam, imazapyr (i
mazapyr), imazethapyr (imazethap)
yr), imazaquin, imazamox, imazames
meth), imazametabenz (imazametha)
benz), pyridiobac-sodiu, pyriothiobac-sodium salt
m), bispyribac sodium salt (bispyrib)
ac-sodium), pyriminobac-methyl (pyr)
Pyrimidinyl salicylic acid such as iminobac-methyl, other glyphosate-ammonium salts, glyphosate isopropylamine salt (glyphosate-)
isopropyl amine), glufosinate ammonium salt (glufosinate-ammoni)
um), bialaphos, etc., which are said to exhibit herbicidal efficacy by inhibiting the biosynthesis of amino acids in plants.

(8) Trifluraline
lin), oryzalin, nitralin, pendimethalin (pend)
imetalin), ethalfluralin (ethalin)
dinitroaniline, such as fluralin, amiprofos-methy
l), butamifos, anilofos, piperophos
os), chlorpropham (chl)
or phenyl carbamates such as barban, daimulon (daimu).
ron), cumyluron, cumylamines such as bromobutide, other asuram, dithiopyr, thiazopyr
Such as yr), which are said to exhibit herbicidal efficacy by inhibiting plant mitosis.

(9) EPTC, butyrate (butyl)
ate), molinate, dimepiperate, esprocarb, thiobencarb (thiob)
encarb), pyributic
thiocarbamates such as arch), alachlor, butachlor (butachl)
or), pretilachlor
r), metolachlor, tenylchlor, dimethenamide, acetochlor (a)
cetochlor, propachlor
chloroacetamides such as hlor), ethobenzanide, mefenacet, thiafluamide (th
iafluamide, tridifan
phase, cafenstrol (cafenstr)
ole), fentrazamide
e), oxazicromef
on), indanophan, and flufenacet, which are said to exhibit herbicidal efficacy by inhibiting protein biosynthesis or lipid biosynthesis in plants.

Further, as shown in Test Examples 1, 2 and 3 below, the compound of the present invention was obtained from corn, soybean, wheat,
Although it has safety to crops such as rice, and includes those showing selectivity for controlling weeds well, when the compound of the present invention is used in crop cultivation, the active ingredient compound of the other herbicides Among them, synergistic effects may be obtained by mixing or using one or more of the following compounds, for example.

Cultivation of corn; 2,4-D, MCP
A, dicamba, clopyralid, benazoline, diflufenzopyr, diuron, linuron, metobenzuron,
Simazine, atrazine, attraton, metribuzin, terbutyrazine, cyanazine, amethrin, cypromid, bromoxynil, bromoxynil octanoate, pyridate, bentazone, paraquat, oxyfluorfen, flumicrolacpentyl, fluciacet methyl, fluridone, sulcotrione, mesotrione, isoxafluon Thor, carfentrazone-ethyl,
Primisulfuron-methyl, rimsulfuron, nicosulfuron, prosulfuron, halosulfuron-methyl, thifensulfuron-methyl, flumeturam, metoslam, imazethapyr, glyphosate ammonium salt, glyphosate isopropylamine salt, glufosinate ammonium salt, trifluralin, pendimethalin, EPTC, Butyrate, alachlor, metolachlor, acetochlor, propachlor, dimethenamide, tridiphane

Cultivation of soybean; 2,4-D, linuron,
Metribuzin, cyanazine, bentazon, paraquat,
Acifluorfen sodium salt, fomesafen, lactofen, flumicrolacpentyl, fluthiacet methyl, sulfentrazone, norflurazon, clomazone, fluazifopbutyl, quizalofopethyl, fenoxapropethyl, cresodim, sethoxydim,
Chlorimuron-ethyl, thifensulfuron-methyl, oxasulfuron, flumeturum, imazapyr, imazethapyr, imazaquin, imazamox, trifluralin, pendimethalin, etalfluralin, alachlor, metolachlor, acetochlor, flufenaset

Cultivation of wheat; MCPB, kimmerak,
Linuron, isoproturon, promethrin, bromoxynil, bromoxynil octanoate, pyridate, bifenox, carfentrazone-ethyl, thidiadimine, pyraflufen-ethyl, flurtamon, difluphenican, sulcotrione, diclohop-methyl,
Tralkodymium, Chlorsulfuron, Methosulfuron-methyl, Prosulfuron, Halosulfuron-methyl, Flumetrum, Methoslam, Pendimethalin, Burban, Imazametabenz

Cultivation of rice; 2,4-D, MCPA, MC
PB, naproanilide, quinclorac, simetryn,
Promethrin, dimethamethrin, propanil, swep, bentazone, nitrofen, clomethoxyfen,
Bifenox, oxadialgyl, oxadiazon,
Sulfentrazone, carfentrazone ethyl, pentoxazone, pyrazolate, pyrazoxifene, benzofenap, methoxyphene, cyhalofop butyl, bensulfuronmethyl, sinosulfuron, pyrazosulfuronethyl, azimsulfuron, imazosulfuron, cyclosulfamuron, Ethoxysulfuron, sodium bispyribac, pyriminobac-methyl, anilofos,
Piperophos, daimuron, cumyluron, bromobutide,
Dithiopyr, molinate, dimepiperate, esprocarb, thiobencarb, pyributicarb, tenylchlor, pretilachlor, butachlor, etobenzanide, mefenacet, cafenstrole, fentrazamide, indanophan

[0059]

EXAMPLES Next, examples of the present invention will be described, but the present invention is not limited to these examples. First, a synthesis example of the compound of the present invention will be described.

Synthesis Example 1 2- (3-trifluoromethylphenoxy) -6-hydroxy-4-methoxypyridine (Compound No. 1 described below)
Synthesis of 2) (1) 1.9 g of 60% oily sodium hydride was added to 20 ml of tetrahydrofuran, and a solution in which 5.8 g of benzyl alcohol was dissolved in 10 ml of tetrahydrofuran was gradually added dropwise with cooling and stirring. After completion of the dropwise addition, the mixture was stirred at room temperature for 30 minutes, cooled again, and a solution of 8.0 g of 2,6-dichloro-4-methoxypyridine dissolved in 20 ml of tetrahydrofuran was gradually added dropwise. After completion of the dropwise addition, the mixture was reacted for 2 hours under heating and reflux. After completion of the reaction, the reaction solution was allowed to cool, and the reaction solution was poured into water. After neutralization with hydrochloric acid, the mixture was extracted with ethyl acetate. The organic layer was washed with water, dried over anhydrous sodium sulfate, and the solvent was distilled off under reduced pressure. The residue was separated and purified by silica gel column chromatography (developing solvent: n-hexane / ethyl acetate = 85/15) to obtain 12.0 g of 2-benzyloxy-6-chloro-4-methoxypyridine.

(2) 2.0 g of 60% oily sodium hydride
Was added to 20 ml of dimethylformamide, and 7.5 g of 3-hydroxybenzotrifluoride was added thereto.
The solution dissolved in 10 ml was gradually dropped under cooling and stirring.
After completion of the dropwise addition, the mixture was stirred at room temperature for 1 hour, cooled again, 4.4 g of copper iodide and 1.8 g of pyridine were added, and 11.5 g of 2-benzyloxy-6-chloro-4-methoxypyridine was dissolved in 10 ml of dimethylformamide. The solution was gradually dropped. After the completion of the dropwise addition, the reaction was carried out at 80 ° C. for 5 days. After completion of the reaction, the reaction solution was allowed to cool, and the reaction solution was poured into water. A saturated aqueous ammonium chloride solution was added, and the mixture was extracted with ethyl acetate. The organic layer was washed with water, dried over anhydrous sodium sulfate, and the solvent was distilled off under reduced pressure. The residue was separated and purified by silica gel column chromatography (developing solvent: n-hexane / ethyl acetate = 85/15) to give 4.9 g of 2-benzyloxy-6- (3-trifluoromethylphenoxy) -4-methoxypyridine. Obtained. (3) Dissolve 4.9 g of 2-benzyloxy-6- (3-trifluoromethylphenoxy) -4-methoxypyridine in 50 ml of dry methanol, add catalytic amounts of palladium chloride and palladium carbon, and pressurize under hydrogen gas pressure. The reaction was performed at room temperature for 5 hours. After completion of the reaction, the reaction solution was filtered, and the solvent was distilled off from the filtrate under reduced pressure. The residue was separated and purified by silica gel column chromatography (developing solvent: n-hexane / ethyl acetate = 1/3) to give a melting point of 152 to 154.
3.2 g of the desired product having a temperature of ° C. was obtained.

Synthesis Example 2 2- (1,2-dichloro-1-propenyloxy-3-
Yl) -6- (3-trifluoromethylphenoxy)-
Synthesis of 4-methoxypyridine (Compound No. 121) 3.0 g of 2- (3-trifluoromethylphenoxy) -6-hydroxy-4-methoxypyridine was dissolved in 30 ml of dimethyl sulfoxide, and 1.4 g of potassium carbonate and E were added thereto. Body
1.7 g of 1,2,3-trichloropropene in a Z form was added, and the mixture was reacted at 80 ° C. for 2 hours. After completion of the reaction, the reaction solution was allowed to cool, and the reaction solution was poured into water. After neutralization with hydrochloric acid, the mixture was extracted with ethyl acetate. The organic layer was washed with water, dried over anhydrous sodium sulfate, and the solvent was distilled off under reduced pressure. The residue was separated and purified by silica gel column chromatography (developing solvent: n-hexane / ethyl acetate = 3/1) to obtain 2.6 g of an oily product of a mixture of E-form and Z-form.

Synthesis Example 3 2- (3-trifluoromethylphenoxy) -6-hydroxy-4-methoxypyridine (Compound No. 1 described below)
Synthesis of 2) (1) 940 mg of potassium carbonate was added to dimethyl sulfoxide 10
3-hydroxybenzotrifluoride
1.1 g was added dropwise and stirred at room temperature for 30 minutes. Then, 2,6
-Dichloro-4-methoxypyridine (1.1 g) was added at 110 ° C.
For 18 hours. After completion of the reaction, the reaction solution was allowed to cool, the reaction solution was poured into water, and extracted with ethyl acetate. The organic layer was washed with water, dried over sodium sulfate, and the solvent was distilled off under reduced pressure. The residue was subjected to silica gel column chromatography (developing solvent: n-
Hexane) to give 1.28 g of oily 6-chloro-4-methoxy-2- (3-trifluoromethylphenoxy) pyridine. (2) 6 mg of 6-chloro-4-methoxy-2- (3-trifluoromethylphenoxy) pyridine and 220 mg of potassium hydroxide are dissolved in 10 ml of tert-butanol,
The reaction was performed under reflux for 5 hours. After completion of the reaction, the reaction solution was allowed to cool, the reaction solution was poured into water, and extracted with ethyl acetate. The organic layer was washed with water, dried over sodium sulfate, and the solvent was distilled off under reduced pressure. The residue was separated and purified by silica gel column chromatography (developing solvent: n-hexane / ethyl acetate = 4/1) to obtain 100 mg of a mixture of the desired product and its decomposition product.

Synthesis Example 4 2- (3-trifluoromethylphenoxy) -6-hydroxy-4-methylthiopyridine (Compound No. 1 described below)
Synthesis of 5) (1) 1.2 g of potassium carbonate was added to 10 ml of dimethyl sulfoxide
In addition to 3-hydroxybenzotrifluoride 1.
4 g was added dropwise, and the mixture was stirred at room temperature for 30 minutes. Then,
1.5 g of dichloro-4-methylthiopyridine was added, and 110 ° C.
For 5 hours. After completion of the reaction, the reaction solution was allowed to cool, the reaction solution was poured into water, and extracted with ethyl acetate. The organic layer was washed with water, dried over sodium sulfate, and the solvent was distilled off under reduced pressure. The residue was subjected to silica gel column chromatography (developing solvent: n-
Hexane) to give 1.2 g of 6-chloro-4-methylthio-2- (3-trifluoromethylphenoxy) pyridine. (2) 6-chloro-4-methylthio-2- (3-trifluoromethylphenoxy) pyridine (600 mg) and potassium hydroxide (300 mg) were dissolved in tert-butanol (10 ml).
The reaction was carried out at reflux for 5 hours. After completion of the reaction, the reaction solution was allowed to cool, the reaction solution was poured into water, and extracted with ethyl acetate. The organic layer was washed with water, dried over sodium sulfate, and the solvent was distilled off under reduced pressure. The residue was separated and purified by silica gel column chromatography (developing solvent: toluene / ethyl acetate = 5/1) to obtain 30 mg of the desired product having a melting point of 120 to 121 ° C.

Synthesis Example 5 Synthesis of 6-methoxy-3-nitro-2- (3-trifluoromethylphenoxy) pyridine (Compound No. 32) 1.0 g of potassium carbonate was added to 4 ml of dimethyl sulfoxide.
1.0 g of 3-hydroxybenzotrifluoride under cooling and stirring
Was added dropwise and stirred at room temperature for 30 minutes. Thereafter, 1.15 g of 2-chloro-6-methoxy-3-nitropyridine was added,
The reaction was performed at 80 ° C. for 4 hours. After completion of the reaction, the reaction solution was allowed to cool, the reaction solution was poured into water, and extracted with ethyl acetate. Wash the organic layer with water,
After drying over sodium sulfate, the solvent was distilled off under reduced pressure. The residue was subjected to silica gel column chromatography (developing solvent:
n-hexane / ethyl acetate = 4/1).
1.77 g of an oily target product was obtained.

Synthesis Example 6 Synthesis of 3-amino-6-methoxy-2- (3-trifluoromethylphenoxy) pyridine (Compound No. 33) 6-methoxy-3-nitro-2- (3-trifluoromethyl Phenoxy) pyridine 1.0 g and palladium carbon 100 mg
Was added to 10 ml of ethanol, and reacted at room temperature for 5 hours under hydrogen gas pressure. After completion of the reaction, the reaction solution was filtered, and the solvent was distilled off from the filtrate under reduced pressure. The residue was separated and purified by silica gel column chromatography (eluent: n-hexane / ethyl acetate = 4/1) to give 800 mg of the desired product as an oil.

Synthesis Example 7 3-dimethylamino-6-methoxy-2- (3-trifluoromethylphenoxy) pyridine (Compound No.
34) Synthesis of 6-methoxy-3-nitro-2- (3-trifluoromethylphenoxy) pyridine 1.0 g with dimethylformamide
In addition to 10 ml, 2 ml of 30% formaldehyde and 2 ml of formic acid were added dropwise at 80 ° C. and reacted at the same temperature for 2 hours. After the reaction is completed, the reaction solution is left to cool, and the reaction solution is poured into an aqueous sodium carbonate solution.
Extracted with ethyl acetate. The organic layer was washed with water, dried over sodium sulfate, and the solvent was distilled off under reduced pressure. The residue was separated and purified by silica gel column chromatography (eluent: n-hexane / ethyl acetate = 5/1) to give the oily target compound.
830 mg were obtained.

Next, Table 1 shows typical examples of the compounds of the present invention represented by the above formula (I), and Table 2 shows NMR spectrum data of these compounds. Table 3 shows typical examples of the intermediate compound represented by the formula (IV), and Table 4 shows NMR spectrum data of the compound. These compounds can be synthesized based on the above-mentioned Synthesis Examples or various methods for producing the compound of the present invention or the intermediate compound. The abbreviations used in Tables 1 and 3 have the following meanings, respectively. Me: methyl group, Et: ethyl group, Pr:
Propyl group, Bu: butyl group, Hex: hexyl group, Cy: cyclo, n: normal, i: iso. Cy-Hex (2-Cl) is 2-
Indicates a chlorocyclohexyl group. The same applies to other similar descriptions. In Tables 1 and 3, when R ₁ is “−”, n is 0.

[0069]

[Table 1]

[0070]

[Table 2]

[0071]

[Table 3]

[0072]

[Table 4]

[0073]

[Table 5]

[0074]

[Table 6]

[0075]

[Table 7]

[0076]

[Table 8]

[0077]

[Table 9]

[0078]

[Table 10]

[0079]

[Table 11]

[0080]

[Table 12]

[0081]

[Table 13]

[0082]

[Table 14]

[0083]

[Table 15]

Next, test examples of the present invention will be described. Test Example 1 Upland soil was filled in a 1 / 170,000 ha pot and seeds of various plants were sown. Thereafter, the plants were maintained at a certain leaf age ((1) Nobier 1.8-2.3 leaf stage, (2) Meishishiba 1.6-1.9 leaf stage, (3) Aogaito 0.2-0.6
Leaf stage, (4) American sika deer 0.2-0.5 leaf stage,
(5) Malva morning glory 0.5-1.1 leaf stage, (6) Onami fir 0.8-1.6 leaf stage, (7) Rice 1.7-2.1 leaf stage,
(8) Wheat 2.1-2.8 leaf stage, (9) Maize 2.
3 to 2.9 leaf stage, (10) soybean primary leaf stage)
A wettable powder prepared from the compound of the present invention in accordance with a usual preparation method was weighed so as to have a predetermined amount of the active ingredient, and diluted with 500 liters of water per hectare. Further, 0.1% by volume of an agricultural spreading agent was added to the diluted solution, and foliage treatment was performed with a small spray.

On the 21st to 22nd days after the chemical treatment, the growth state of various plants was visually observed.
The herbicidal effect was evaluated using the weeding rate (%) of (complete killing).
The results in the table were obtained.

[0086]

[Table 16]

Test Example 2 Upland soil was filled in a 1 / 170,000 hectare pot, and seeds of various plants (Nobie, Mehisiba, Aogayto, American stag, Malva Asagao, Onamimomi,
Rice, wheat, corn and soybean).
The next day after sowing, a wettable powder prepared according to the usual formulation method of the compound of the present invention was weighed so as to have a predetermined amount of the active ingredient, and diluted with 1500 liters of water per hectare and subjected to soil treatment with a small spray.

On the 21st to 22nd days after the chemical treatment, the growth state of various plants was visually observed.
The herbicidal effect was evaluated using the herbicidal rate (%) of (complete killing).
The results in the table were obtained.

[0089]

[Table 17]

Test Example 3 A paddy field soil was filled in a 1 / 1,000,000 hectare pot, and seeds of nobie and firefly were sown and lightly covered with soil. Then, it was allowed to stand still in a greenhouse at a waterlogging depth of 0.5 to 1 cm, and two days later, Urikawa tubers were implanted. After that, the depth of flooding was kept at 3 to 4 cm, and when Nobie and Firefly reached the 0.5 leaf stage, and Urikawa reached the primary leaf stage, the compound of the present invention was diluted with water in a wettable powder prepared according to a usual formulation method. The liquid was uniformly dropped with a pipette so as to have a predetermined amount of the active ingredient.

Further, paddy soil was filled in a 1 / 1,000,000 hectare pot, paddy was padded, and the flooding depth was 3-4.
cm, and one day later, rice at the 2 leaf stage (variety: Nipponbare) was transplanted to a transplantation depth of 3 cm. Four days after transplantation, the compound of the present invention was treated in the same manner as described above. Nobie on the 14th day after drug treatment,
On the 21st day after the chemical treatment, the growth status of fireflies and urikawa were visually observed, and the herbicidal effect was evaluated at a weeding rate (%) of 0 (equivalent to the untreated area) to 100 (complete killing). It was evaluated and the results shown in Table 7 were obtained.

[0092]

[Table 18]

Next, preparation examples of the present invention will be described. Formulation Example 1 (1) Compound of the present invention 75 parts by weight (2) Geropon T-77 (trade name; manufactured by Rhone Poulin Co.) 14.5 parts by weight (3) 10 parts by weight of NaCl (4) 0.5 part by weight of dextrin Put each of the above components into a high-speed mixing fine granulator,
Add 0% water, granulate and dry to obtain a wettable powder.

Formulation Example 2 (1) 78 parts by weight of kaolin (2) Labelin FAN (trade name; manufactured by Daiichi Kogyo Seiyaku Co., Ltd.) 2 parts by weight (3) Solpol 5039 (trade name; manufactured by Toho Chemical Industry Co., Ltd.) 5 parts by weight (4) Carplex (trade name; manufactured by Shionogi & Co., Ltd.) 15 parts by weight At least 9: 1 by weight of the mixture of the components (1) to (4) and the compound of the present invention. Mix to obtain wettable powder.

Formulation Example 3 (1) High Filler No. 10 (trade name; manufactured by Matsumura Sangyo Co., Ltd.) 33 parts by weight (2) Solpol 5050 (trade name; manufactured by Toho Chemical Industry Co., Ltd.) 3 parts by weight (3) Solpol 5073 (trade name: Toho Chemical Industry Co., Ltd.) 4 parts by weight (4) Compound of the present invention 60 parts by weight The above components (1) to (4) are mixed to obtain a wettable powder.

Formulation Example 4 (1) The present compound 4 parts by weight (2) Bentonite 30 parts by weight (3) Calcium carbonate 61.5 parts by weight (4) Toxanone GR-31 A (trade name; Sanyo Chemical Industry Co., Ltd.) 3 parts by weight (5) 1.5 parts by weight of calcium ligninsulfonate (1), (2) and (3), which were previously ground, were mixed,
(4), (5) and water are added thereto, mixed, and extruded and granulated. Thereafter, the granules are dried and sized to obtain granules.

Formulation Example 5 (1) 30 parts by weight of the compound of the present invention (2) 60 parts by weight of Siglite (trade name; manufactured by Siglite Co., Ltd.) (3) Newcalgen WG-1 (trade name; Takemoto Yushi Co., Ltd.) )) 5 parts by weight (4) New Calgen FS-7 (trade name, manufactured by Takemoto Yushi Co., Ltd.) 5 parts by weight (1), (2) and (3) were mixed and passed through a pulverizer. After adding (4) and kneading, the mixture is extruded and granulated. afterwards,
Dry and sized to obtain wettable powder.

Formulation Example 6 (1) 40 parts by weight of the compound of the present invention (2) 2 parts by weight of sopropol FL (trade name, manufactured by Rhone Poulin Co.) (3) 0.2 parts by weight of silicon (4) 0.1 parts by weight of xanthan gum Part (5) Ethylene glycol 5 parts by weight (6) Water 52.7 parts by weight The above components (1) to (6) are mixed and pulverized using a wet pulverizer (Dyno-mill) to give an aqueous suspension. Get the agent.

 ────────────────────────────────────────────────── ─── Continued on the front page (72) Inventor Noriko Kishiro 2-3-1 Nishi-Shibukawa, Kusatsu-shi, Shiga F-term in the Central Research Laboratory of Ishihara Sangyo Co., Ltd. 4C055 AA01 BA03 BA39 BA42 BA47 BB01 BB02 BB04 BB07 BB10 CA01 CA02 CA03 CA05 CA06 CA13 CA39 CA51 CA52 CA57 CA59 CB01 CB02 DA01 DA05 DA06 DA13 DA16 DA42 DA47 DA52 DA57 DA58 DB01 DB02 FA01 FA32 FA37 4H011 AB01 AB02 DA02 DA14 DD03

Claims (8)

[Claims] (1) Formula (I): (Wherein R ₁ is halogen, alkyl, haloalkyl, alkoxyalkyl, cyanoalkyl, alkoxy, haloalkoxy, alkoxyalkoxy, alkylthio, haloalkylthio, alkenyl, alkynyl, amino, monoalkylamino, dialkylamino, alkylsulfinyl, alkylsulfonyl , Alkoxycarbonyl,
Dialkylaminocarbonyl, cyano or nitro, R ₂ is a hydrogen atom, an optionally substituted alkyl, an optionally substituted alkenyl, an optionally substituted alkynyl or an optionally substituted cycloalkyl; An atom or a sulfur atom, n is an integer of 0 to 3,
Wherein R ₁ is the same or different when R is 2 or more) or a salt thereof. 2. A compound represented by the formula (I-1): (Wherein R ₁ is halogen, alkyl, haloalkyl, alkoxyalkyl, cyanoalkyl, alkoxy, haloalkoxy, alkoxyalkoxy, alkylthio, haloalkylthio, alkenyl, alkynyl, amino, monoalkylamino, dialkylamino, alkylsulfinyl, alkylsulfonyl , Alkoxycarbonyl,
Dialkylaminocarbonyl, cyano or nitro, X is an oxygen atom or a sulfur atom, n is an integer of 0 to 3, and when n is 2 or more, R ₁ may be the same or different) A process for producing a phenoxypyridine compound or a salt thereof represented by the following formula (1): Wherein R ₁ , X and n are as described above, and Bn is benzyl which may be substituted by alkyl or alkoxy. ) A hydrogenation reaction using a compound of formula (II), or (3) a debenzylation reaction in the presence of an oxidizing agent using a compound of formula (II), A method comprising producing a compound of the formula (I-1). (3) Formula (I-2): (Wherein R ₁ is halogen, alkyl, haloalkyl, alkoxyalkyl, cyanoalkyl, alkoxy, haloalkoxy, alkoxyalkoxy, alkylthio, haloalkylthio, alkenyl, alkynyl, amino, monoalkylamino, dialkylamino, alkylsulfinyl, alkylsulfonyl , Alkoxycarbonyl,
Dialkylaminocarbonyl, cyano or nitro, R ₂ ′ is an optionally substituted alkyl, an optionally substituted alkenyl, an optionally substituted alkynyl or an optionally substituted cycloalkyl, and X is an oxygen atom or A sulfur atom, n is an integer of 0 to 3, and when n is 2 or more, R ₁ may be the same or different), or a salt thereof. And (1) Formula (I-1); Wherein R ₁ , X and n are as defined above, and a compound of formula (III); (Wherein R ₂ ′ is as described above and Z ₁ is halogen), or a compound represented by the formula (2)
(IV); (Wherein R ₁ and n are as described above, and Z ₃ is halogen), and a compound represented by the formula (V): (Wherein R ₂ ′ and X are as defined above), or by the method of the above formula (I
-2) The method characterized by producing the compound of the above. (4) a compound represented by the formula (I-2): (Wherein R ₁ is halogen, alkyl, haloalkyl, alkoxyalkyl, cyanoalkyl, alkoxy, haloalkoxy, alkoxyalkoxy, alkylthio, haloalkylthio, alkenyl, alkynyl, amino, monoalkylamino, dialkylamino, alkylsulfinyl, alkylsulfonyl , Alkoxycarbonyl,
Dialkylaminocarbonyl, cyano or nitro, R ₂ ′ is an optionally substituted alkyl, an optionally substituted alkenyl, an optionally substituted alkynyl or an optionally substituted cycloalkyl, and X is an oxygen atom or A sulfur atom, n is an integer of 0 to 3, and when n is 2 or more, R ₁ may be the same or different), or a salt thereof. And the formula (VI): (Wherein R ₁ , R ₂ ′, X and n are as described above, and Z
₂ is halogen) and a compound represented by the formula (VII): A method characterized by reacting with a compound represented by the formula: (5) a compound represented by the formula (I-3): (Wherein R ₁ is halogen, alkyl, haloalkyl, alkoxyalkyl, cyanoalkyl, alkoxy, haloalkoxy, alkoxyalkoxy, alkylthio, haloalkylthio, alkenyl, alkynyl, amino, monoalkylamino, dialkylamino, alkylsulfinyl, alkylsulfonyl , Alkoxycarbonyl,
Dialkylaminocarbonyl, cyano or nitro, n is an integer of 0 to 3, and R ₁ when n is 2 or more;
May be the same or different), and a phenoxypyridine-based compound represented by the formula (IV): (Wherein R ₁ and n are as described above, and Z ₃ is halogen), and potassium hydroxide and te
A method characterized by reacting with rt-butanol. 6. A herbicide comprising the phenoxypyridine-based compound of claim 1 or a salt thereof as an active ingredient. 7. A method for controlling harmful weeds, to which an effective amount of the phenoxypyridine compound or its salt according to claim 1 is applied. 8. A mixed herbicidal composition comprising at least one phenoxypyridine-based compound or a salt thereof according to claim 1 and at least one active compound of another herbicide.