JPS63166856A - 2-nitro-5-(substituted phenoxy)benzohydroximic acid derivative and herbicide containing said derivative - Google Patents

Abstract

NEW MATERIAL:The 2-nitro-5-(substituted phenoxy)benzohydroximic acid derivative of formula I [R<1> is lower alkyl; R<2> is H or lower alkyl; R is (substituted) alkenyl or (substituted)alkynyl]. EXAMPLE:Methyl O-allyloxycarbonylmethyl 5-(2-chloro-4-trifluoromethylphenoxy)- 2-nitrobenzohydroximate. USE:A herbicide having broad herbicidal spectrum and excellent selective herbicidal activity and effective at a decreased rate of application. Excellent characteristics can be exhibited especially by foliar treatment. PREPARATION:The compound of formula I can be produced e.g. by reacting an o-carboxyalkyl-2-nitro-5-(substituted phenoxy)benzohydroximic acid ester of formula II with a halogen compound of formula III (X is halogen).

Description

Detailed Description of the Invention Technical Field The present invention relates to the following formula (I), where 11 represents a lower alkyl group, R1 represents a hydrogen atom or a lower alkyl group, and R represents an optionally substituted alkenyl group. In addition, 2-nitro s-(
mm phenoxy)benzohydroxymic acid derivatives. The compound of formula (I) is useful, for example, as an adjunct exhibiting herbicidal activity. Therefore, the present invention also provides a herbicide containing the compound of formula (I) as an active ingredient. related.

The novel benzohydroxymic acid derivative represented by the above formula (I) of the present invention has extremely excellent herbicidal activity against weeds, and exhibits its effect before and after the weed germination and during the growth period, and is especially effective against weeds. Shows the most powerful herbicidal activity during the growing season.

Prior art Japanese Patent Application Laid-open No. 60-226856 describes the following general formula (4) as a new diphenyl ether oxime ester derivative.
) is disclosed.

is oxygen or sulfur; R is halogen, nitro group, cyano group, alkyl group, haloalkyl group, alkylthio group, haloalkylthio group, alkoxy group, haloalkoxy group,
Sulfonamide group, dialkylsulfonamide group, alkylsulfonyl group, haloalkylsulfonyl group, alkylsulfinyl group or haloalkylsulfinyl group:
R''H hydrogen, halogen, cyano group, alkyl group, haloalkyl group, cyanoalkyl group, alkoxy group, haloalkoxy group, cyanoalkoxy group, alkylthio group, haloalkylthio group, cyanoalkylthio group, mono- or dialkylamino group, alkylthioalkyl group or mono- or dialkylaminoalkyl group; R3 is C1-
C, an alkylene group or an alkenyl group, which may be substituted with an alkyl group, a haloalkyl group, a cyanoalkyl group or a hydroxyl group; Q is 10R1 or 18R'': R' is an alkoxyalkyl group , thioalkyl group, cyanoalkyl group, cycloalkyl group,
hydroxyalkyl group, carbalkoxyalkyl group,
An alkylthioalkyl group, an aralkyl group, a sulfonamido group, or a 4- to 6-membered heterocyclic compound containing up to 3 heteroatoms in the ring, or a heterocycle containing up to 5 heteroatoms in the ring. An alkyl group substituted with a compound of the formula.

In the above formula compound which can include a very large number of compounds, X includes CH(7), R includes halogen and haloalkyl, and Y includes NO! , including the case of R"fl alkoxy, including the case of R 2 'alkylene which may be substituted with alkyl, and including the case where 2 is an oxygen atom. However, in the formula The definition of R1 when Q is -OR'' includes an alkenyl group that may have a substituent or an alkenyl group that may have a substituent as specified for R in the compound of formula (I) of the present invention. Good alkynyl groups cannot be included. Therefore, as a matter of course, JP-A No. 60-226856 does not mention any of the compounds of the formula (I) of the present invention, their production method, or herbicidal activity; )
There is no suggestion as to the possible existence of the compound or any usefulness of the compound of formula (I).

Furthermore, JP-A No. 60-226856 does not provide any specific examples of compounds in which R1 in the formula (g) is an alkoxy group or a substituted alkoxy group, and its synthesis. In the compounds mentioned above, R1 is only a methyl group, and preferred examples of B1 include an alkyl group or a haloalkyl group.

Furthermore, although there is a general statement in JP-A-6Q-226856 that the formula compound has herbicidal activity, there is no specific data that can confirm such herbicidal activity. Fever, not shown.

As another proposal, Japanese Patent Application Laid-Open No. 56-52452 discloses that a compound of the following formula 03) and a compound (B) have herbicidal activity. In training (B),
is NO8, halogen or CN:Y is Hl or c t
: When zFiyc t”c, Ct is the same, or 2 is H when Y is H or Ct; R is H
or alkyl up to Cs and SR' is H or C
H, and R1 are alkyl or agriculturally soluble salt ions up to H%CIO.

RFi in the compounds specified in this proposal
The compound of the formula (I) of the present invention cannot include the specified OR', and R1 in the compound of the formula (B) of the present invention is a compound of the formula (f) of the present invention.
) cannot include R specified in the compound.

Therefore, although it is a matter of course, the said JP-A-56-5
No. 2452 also makes no mention of the compound of formula (I) of the present invention, its production method, or its herbicidal activity, and there is no mention of the possibility of the existence of the compound of formula (I) or any usefulness thereof. Heat not suggested.

Problems to be Solved Meanwhile, in recent years, it has become essential to use herbicides to protect important crops such as corn, soybeans, wheat, rice, cotton, and beets from weed damage and to increase yields. These herbicides are foliage-contact type herbicides that can be applied after germination depending on the grass type and amount, and can be expected to reduce the amount of cross-removal agent, compared to soil treatment type herbicides that are applied before germination. is desired.

However, since crops also come into contact with foliage-contact herbicides, extremely high selectivity is required.

Therefore, although many soil treatment types have been developed, there are very few foliage contact types.

Currently, the foliar contact herbicides used in soybean fields include diazine-based 3-ingrovir-IH-2,1,
3-benzothiadiazine (4) -5H-one-2,2
- Dioxole (pentacine), diphenyl ether-based sodium 5-(2-chloro-4-trifluoromethylphenoxy)-2-nitrobenzoate (acifluorophen-sodium), etc., have their herbicidal activity, The herbicidal spectrum is not satisfactory, and the emergence of a more effective foliage contact herbicide is eagerly awaited.

Summary of the Invention The present inventors have overcome the technical problems of the above-mentioned foliar treatment type diphenyl ether herbicide, and have developed a herbicide that requires a small application amount, has a wide herbicidal spectrum, and is a good choice even when sprayed on major crops after germination. Intensive research efforts have been made to develop a diphenyl ether herbicide with the following properties:

As a result, they found that a compound represented by the above formula (RI) and described in a conventionally known literature could exist, and succeeded in its synthesis.Furthermore, the new compound (I) has excellent herbicidal activity, Herbicidally active compounds capable of overcoming technical challenges in technology, with reduced application rates, broad herbicidal ranges (
It has been discovered that ctram is a tr compound that exhibits excellent selective herbicidal action and can exhibit excellent properties when applied, for example, in soil treatments and foliar treatments, particularly in foliage treatments.

Thus, according to the present invention, the following formula (I), where R1
represents a lower alkyl group, R1 represents a hydrogen atom or a lower alkyl group, and R represents an optionally substituted alkenyl group or an optionally substituted alkynyl group. Substituted phenoxy)benzohydroxymic acid derivatives can be provided.

Furthermore, according to the present invention, it is possible to provide a herbicide characterized by containing the above compound of formula (I) as an active ingredient.

Effects of the Invention The diphenyl ether derivative represented by the above formula (I) of the present invention is a novel compound that has not been described in any literature.

The diphenyl ether derivative of the present invention represented by the above formula (I) is a phenyl ring having a nitro group (sometimes referred to as B block) at the ortho position of the nitro group of the diphenyl ether, and which is specified by the above formula (I) and is conventionally known. The herbicide containing the diphenyl ether derivative of formula (I) exhibits the excellent properties of the herbicide containing the diphenyl ether derivative due to its structural characteristics. it is conceivable that.

The herbicide of the present invention has selectivity for rice, corn, wheat, barley, turgium, soybean, etc. 1. i6
It is a herbicide with excellent properties that could not be expected from conventional technology, such as having a wide spectrum of herbicides and fully demonstrating its herbicidal activity with far less use than ordinary herbicides.

Detailed Description of the Invention The lower alkyl in 81 and R8 of the diphenyl ether enzyme conductor represented by the formula (I) of the present invention is preferably a lower alkyl group having 1 to 4 carbon atoms, such as methyl, ethyl, n-propyl, 1-7'ropil n-
Examples include butyl, chlorobutyl, 1-butyl, and the like.

Examples of substituents that R in formula (I) may have include, for example, a halogen atom, a CI''C4 alkoxy group, a cyano group, an alkylthio group having a C1''C4 alkyl group, c , an alkoxycarbonyl group having a -c4 alkoxy group, and the like.Furthermore, general alkenyl groups include C1-C alkenyl groups such as allyl, metaallyl, crotyl, etc., and examples of alkynyl groups include pro/#, etc. C such as lugil, 2-butynyl, etc.
, -C, can be exemplified. The compound represented by the above formula (I) has stereoisomers (syn type and an
It should be understood that compounds of formula (I) in the form of optical isomers are within the scope of the definition of compounds of formula (I) of the present invention. be.

Among these examples, preferred examples of compounds of formula (I) include compounds in which R1 is a methyl group, 11 is a hydrogen atom, and R is an alkenyl group or alkynyl group that may be substituted with halogen, especially chlorine, especially a C3 alkenyl group. (−
CHtCH= CHt ) or C8 alkynyl group (
-C)1. C3CH) compounds can be mentioned.

The compound of the present invention represented by the above formula (I) can be produced, for example, by the method shown below.

(I0(III) [During the ceremony 11, H! and R are the same as defined above.

X represents a halogen atom. ] Hydroxymic acid ester (I0 and halogen compound (II)
I) can be reacted, for example, in an organic solvent in the presence of a base to produce compounds of formula (I) of the invention.

According to this embodiment, the scheestone contains, for example, 1 to 5 molar equivalents of compound (III) relative to compound (U), preferably 1
The reaction can be carried out under conditions such as water cooling or the reflux temperature of the solvent, preferably at room temperature to around 80° C., for example, α5 to 20 hours, using a weight of 1.5 to 1.5 degrees Celsius.

Examples of solvents used in this reaction include aromatic hydrocarbons such as benzene and toluene; ethers such as tetrahydrofuran and dioxane; one or more organic solvents such as acetone, acetonitrile, dimethylformamide, and dimethyl sulfoxide; An example is a mixed solvent of a solvent and water.

Examples of the base used in the above reaction include pyridine, triethylamine, sodium hydroxide, potassium hydroxide, sodium carbonate, potassium carbonate, sodium hydrogen carbonate, potassium hydrogen carbonate, and sodium hydride. The amount of the base exemplified above that acts as a dehydrohalogenation agent can be selected as appropriate;
) By using 1 to 3 equivalents, preferably 1 to 1.5 equivalents, the reaction can be carried out in high yield.

Compounds of formula (2) can be prepared according to other embodiments shown below.

(f'/) (to) [in the formula
R1, RR and R are the same as defined above.

X represents halogen or a group -080,R'(R' is a substituted or unsubstituted alkyl group, phenyl group, or alkoxy group). ] According to this aspect, 0-it conversion-2-nitro-5-(t
l-substituted phenoxy)benzhydroxam m = conductor (iV)
and halogen compound (v) 11-1, for example in an organic solvent,
The compound (I) of the present invention can be produced by reaction in the presence of a base.

According to this embodiment, the reaction is carried out using, for example, 1 to 3 molar equivalents of compound (I) to compound (IV), preferably 1 to t5
Used on a molar basis, for example, under water cooling or at the reflux temperature of the solvent, preferably at a temperature between room temperature and around 80 degrees, for example, α
It can be carried out under conditions such as 5 to 20 hours.

Solvents used in this reaction include, for example, alcohols such as methanol and ethanol; aromatic hydrocarbons such as benzene and toluene; ethers such as tetrahydrofuran and dioxane; organic solvents such as acetone, acetonitrile, dimethylformamide, and dimethyl sulfoxide. Examples include one or more of these solvents and a mixed solvent of water.

Examples of the base used in the above reaction include pyridine, triethylamine, sodium hydroxide, potassium hydroxide, sodium carbonate, potassium carbonate-sodium ethylate, and sodium hydride. By using the dehydrohalogenating agent in an amount of 1 to 3 equivalents, preferably 1 to 1.5 equivalents, relative to compound (V), the reaction can be carried out in high yield.

Alternatively, the reaction can be carried out in a two-layer system, in which case quaternary ammonium salts such as tetramethylanthonium bromide, tetrabutylammonium bromide, benzyltributylammonium bromide, etc., quaternary ammonium salts such as tetraphenylphosphonium probide, etc. A phase transfer catalyst such as a grade phosphonium salt is applied to a compound (to) at
t%, preferably 5 to 50 wt%.

In any of the above embodiments, after the reaction is completed, the compound of the present invention can be isolated by pouring the reaction mixture into water and treating it with a conventional method such as extraction with a solvent, recrystallization, column chromatography, etc. I can do it.

Next, a synthesis example of the present invention will be described.

Example 1 [Methyl 0-allyloxycarbonylmethyl 5-(2-/chlor 4-trifluoromedelphenoxy)-2-nitrobenzohydroxymate (compound moiety 1)
Production of methyl local boxymethyl 5-(2-chloro-4-trifluoromethylphenoxy)-2-nitropenzohydroxymer) t,of (2,23 mmol), sodium bicarbonate α19f (2,26 mmol), DM
Allyl bromide l1541 (4,4
6 mmol) and stirred overnight at room temperature. The reaction mixture was poured into about 100 g of ice water, extracted twice with 20 g of ethyl acetate, washed with saturated brine, and dried over magnesium sulfate. After separating the dry scissors with P, the solvent was distilled off and the resulting oily substance was purified by 2-molecular chloridography (silica gel-N-hexane-ethyl acetate 4:1) to obtain the desired compound No. 1 (harvested). 750 cm, yield 6a9%).

Table 1 shows diphenyl ether derivatives of the present invention synthesized in the same manner as in the above examples.

l! Eye Yokaguchi 0o (O Mi1 閤工 国 国
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The compound of the present invention represented by the above formula (I) of the present invention has extremely high herbicidal activity, so it shows an extremely excellent herbicidal effect even when used in a small amount, and has good selectivity for cultivated crops. It can be used as an agriculturally useful herbicide.

The compounds of the present invention can control various weeds growing in rice fields and fields from the pre-emergence stage to the growing season. For example, 1 Nobie, Japanese cypress, Japanese cypress, Japanese azalea, Japanese chickweed, Kikashigusa,
Narrow-leaved and broad-leaved weeds of rice fields such as bulrush and pineweed, black-and-white weed, foxtail grass, black-and-white grass, black-and-white grasshopper, Japanese grasshopper, chickweed, polygonum, barnyard grass, Japanese grasshopper, silver grass, American goldenrod, Japanese fir tree, pigweed, shepherd's purse, shepherd's nape, Japanese cypress, It can control narrow-leaved and broad-leaved weeds such as Yaemugu 2 and Sopakazu 2 in fields.

It can be used not only in paddy fields and fields, but also in orchards, mulberry gardens, and non-agricultural lands.

In particular, the compounds of the present invention exhibit strong herbicidal activity against broad-leaved weeds growing in fields. For example, in the treatment of leaves in fields, it is possible to treat plants such as Aobifolia, Purslane, Ona fir, Sendangusa, Pigweed, etc.
Japanese knotweed, Coacaza, Shiroza, Japanese knotweed, Japanese knotweed, chickweed, shepherd's pear, Japanese oxalis, American hornwort, Ebisugusa, Marupa morning glory, Japanese broom, Japanese staghorn, Hotokenoza, plantain, Japanese oxalis, American goldenrod, Oxalis,
The compound of the present invention exhibits excellent herbicidal effects on weeds such as japonica, buckwheat, turmeric, and poppy.Moreover, the compound of the present invention has selectivity for cultivated crops, and is particularly effective against weeds such as rice, soybean, wheat, barley, turgid, and sugarcane. It does not cause phytotoxicity, which is a practical problem, to broad-leaved crops such as daikon and soybeans.

When the compound of the present invention is actually used as a herbicide,
By mixing with carriers or diluents, additives, and auxiliary agents by a known method, it can be used in formulations commonly used as agricultural chemicals, such as powders, granules, water preparations, emulsions, aqueous solutions, and sol preparations. used. It can also be mixed or used in combination with other agricultural chemicals, such as fungicides, insecticides, acaricides, herbicides, plant growth regulators, fertilizers, soil amendments, and the like.

In particular, when used in combination with other herbicides, it is possible to not only reduce the amount of chemicals used and save labor, but also to expand the herbicidal spectrum due to the synergistic action of both mulberry agents, and to achieve even higher effects due to the synergistic action. .

As the carrier or diluent, commonly used solid or liquid carriers can be used. As solid carriers, clays and talc represented by kaolinite group, monosolirotite group, or atalgite group; mica, leaves,
Inorganic substances such as waxite, pumice, vermiculite, gypsum, calcium carbonate, dolomite, diatomite, magnesium orite, alatite, zeolite, silicic anhydride, synthetic calcium silicate; soybean flour, tobacco flour, walnut flour , wheat flour, wood flour, starch, crystalline cellulose and other vegetable organic substances: coumaron resin, petroleum resin, alkyd resin, polyvinyl chloride, polyalkylene glycol, ketone 'If k
Examples include synthetic or natural polymeric compounds such as ester gum, copalcum, and dammar gum; waxes such as carnaparok and beeswax; and urea.

Suitable liquid carriers include: kerosene, mineral oil, spindle oil, white oil, and other finic or naphthenic hydrocarbons; benzene, toluene, xylene, ethylbenzene, cumene, methylnaphthalene, and other aromatic hydrocarbons; carbon tetrachloride; Chlorinated hydrocarbons such as chloroform, trichloroethylene, monochlorobenzene, and O-chlorotoluene; Ethers such as dioxane and tetrahydro-7rane; Ketones such as acetone, methyl ethyl ketone, diisobutyl ketone, cyclohexanone, acetophenone, and isophorone: ethyl acetate , amyl acetate, ethylene glycol acetate, diethylene glycol acetate,
! Esters such as dibutyl leate and diethyl succinate; alcohols such as methanol, n-hexanol, ethylene glycol, diethylene glycol, cyclohexanol, and benzyl alcohol; ethylene glycol ethyl ether, ethylene glycol phenyl ether,
Examples include ether alcohols such as diethylene glycol ethyl ether and diethylene glycol butyl ether; polar solvents such as dimethyl formamide and dimethyl sulfoxide; and water.

In addition, emulsification, dispersion, wetting, spreading of the compound of the present invention,
Surfactants and other auxiliary agents can also be used for the purposes of binding, adjusting disintegration, stabilizing active ingredients, improving fluidity, preventing rust, and the like. Examples of surfactants that can be used include nonionic, anionic, cationic and zwitterionic surfactants, but typically nonionic and
9) Anionic substances are used. Suitable nonionic surfactants include those obtained by polymerizing ethylene oxide with higher alcohols such as lauryl alcohol, stearyl alcohol, and oleyl alcohol;
Those obtained by polymerizing and adding ethylene oxide to alkylphenols such as isooctylphenol and nonylphenol; Those obtained by polymerizing and adding ethylene oxide to alkylnaphthols such as butylnaphthol and octylnaphthol;
No (products obtained by polymerizing and adding ethylene oxide to higher fats 11 such as lumitic acid, stearic acid, and oleic acid: products obtained by polymerizing and adding ethylene oxide to mono- or dialkyl succinic acids such as stearic acid and dilaurylsinic acid) Nidodecylamine Examples include those obtained by polymerizing and adding ethylene oxide to amines such as 1 stearic acid amide; those obtained by polymerizing and adding ethylene oxide to higher fatty acid esters of polyhydric alcohols such as nrubitan; and those obtained by polymerizing and adding ethylene oxide and propylene oxide. Suitable anionic surfactants include, for example, sodium lauryl sulfate, alkyl fffE & ester salts such as oleyl alcohol sulfate amine salt; alkyl sulfones such as sodium sulfonate and dioctyl ester, sodium 2-ethylhexene sulfonate, etc. Acid salts include arylsulfonates such as sodium isoglobilnaphthalenesulfonate, sodium methylenebisnaphthalenesulfonate, sodium ligninsulfonate, and sthorium dodecylbenzenesulfonate.

Furthermore, the compounds of the present invention include casein, gelatin, albumin,
Glue, sodium alginate, carboxymethylcellulose, methylcellulose, hydroxyethylcellulose,
A polymer compound such as hollyvinyl alcohol or other auxiliary agent can also be used in combination.

The above-mentioned carriers and various auxiliary agents can be used individually or in combination as appropriate depending on the purpose, taking into account the dosage form of the preparation, the application situation, etc.

The active ingredient content of the compound of the present invention in the various formulations thus obtained varies depending on the formulation, but is, for example, 11 to 99 ms.

Preferably it is 1 to 80% by weight.

For powders, for example, the active ingredient compound is usually 1 to 25% by weight.
The remainder is a solid carrier.

Irrigation agents usually contain, for example, 25 to 90% by weight of active ingredient compounds, with the remainder being a solid carrier and a dispersing wetting agent, and if necessary, a colloid agent, a thixotrode agent, an antifoaming agent, etc. may be added.

Granules, for example, usually contain 1 to 35% by weight of the active ingredient compound.
The remainder is mostly solid carrier. The active ingredient compound is homogeneously mixed with the solid carrier or uniformly fixed or adsorbed on the surface of the solid carrier), and the particle size is about α2 to t5 degrees.

Emulsions, for example, usually contain from 1 to 30 parts by weight of the active ingredient compound, including about 5 to 20 parts by weight of an emulsifier, the remainder being a liquid carrier, and optionally a rust inhibitor. Added.

The diphenyl ether compound herbicide of the present invention obtained as described above can be applied as a compound of general formula (I) or in any preparation form as described above.

The herbicide of the present invention can be applied to various weeds growing in paddy fields and fields from the pre-emergence period to the growing season, and it is particularly preferable to apply it to various weeds during the growing season, but it is particularly suitable to apply to fields. be. For its application, the compound of the present invention has extremely high herbicidal activity, so a small amount of application is sufficient, but the selection can be changed as appropriate depending on the type of target weed, growth stage, application location, application time, weather, etc. Already, the amount of the compound (active ingredient amount) represented by general formula (I) per ha is α01~
It is about 100,002, preferably about 11 to 50,002. More preferably, the amount is about 50 to 20,002 per hectare when applied before the emergence of weeds (soil treatment), and about 1 to 1,002 per hectare when applied after the emergence of weeds (X leaf treatment).

Next, several embodiments of formulation examples using the compound of the present invention will be shown.

"1 part" in the following formulation examples is based on weight.

Formulation example 1 (granules) Compound N11115 parts Bentonite 50 parts Merck
40 parts Sodium dodecylbenzenesulfonate 2 parts Guninsulfone soda
After thoroughly mixing 2 parts or more of 1 part or more of polyoxyethylene alkylaryl ether, an appropriate amount of water was added and kneaded, followed by granulation using a granulator to obtain 100 parts of granules.

Formulation Example 2 (Irrigation agent) Compound NIL1 20 parts Diatomysium ± 60 parts White carbon
15 parts Sodium ligninsulfonate
3 parts Sodium dodecylbenzenesulfonate 2
100 parts of an irrigation agent were obtained by mixing and pulverizing the mixture uniformly with a Ni-Goo.

Formulation example 3 (emulsion) Compound Na1 30 parts xylene 55 parts cyclohexanone
10 parts allyl ether
Two or more parts were uniformly mixed and dissolved to obtain 100 parts of an emulsion.

Drugs using the compounds of the present invention were prepared according to the above-mentioned formulation examples.

Test Example 1 (Stem and Leaf Treatment) Field soil was filled in square pots (50 x 30 x 9 ex), and certain amounts of each yuzu crop and various weed seeds shown in Table 2 were sown, and each plant was grown at the t5 to 3 leaf stage ( The cells were grown in a heated container until 18 days after sowing.

The compounds of the present invention shown in Table 2 are acetone; water = 1:
1 (twe@n 20 containing 2% α) was dissolved in a solution of 2% α, and the solution was evenly sprayed on the leaves so that the amount of active ingredients shown in Table 2 was obtained.

On the 21st day after chemical spraying, the herbicidal effect on each weed and the chemical damage to each crop were determined according to the following criteria.
The results are shown in Table 2.

Weeding effect: Percentage from 0 to 100 100...Weed killing rate relative to untreated area is 100% (death) 0...Weed killing rate relative to untreated area is 0% (no effect) Drug Harmful percentage: 20 to 100 100: 100% chemical damage rate (death) compared to untreated area
0... Herb killing rate 0% for untreated area (no chemical damage) Table 2
- (continued) a: 5-(2'-chloro'+ 41-)methylphenoxy)-2-ditonsodium b = methyl-5-(2'-chloro- fluoromethylphenoxy)- acetophenone oxime -〇-

Claims (1)

[Claims] 1. The following formula (I) ▲There are mathematical formulas, chemical formulas, tables, etc.▼...(I) However, in the formula, R^1 represents a lower alkyl group, and R^2 represents a hydrogen atom or A 2-nitro-5-(substituted phenoxy)benzohydroxymic acid derivative represented by: a lower alkyl group, R represents an optionally substituted alkenyl group or an optionally substituted alkynyl group. 2. The following formula (I) ▲There are mathematical formulas, chemical formulas, tables, etc.▼... (I) However, in the formula, R^1 represents a lower alkyl group, R^2 represents a hydrogen atom or a lower alkyl group, R represents an optionally substituted alkenyl group or an optionally substituted alkynyl group, and is characterized by containing as an active ingredient a 2-nitro-5-(substituted phenoxy)benzohydroxymic acid derivative represented by herbicide.