JPH0739400B2 - Triazine derivatives and herbicides containing them as active ingredients - Google Patents

Description

Description: TECHNICAL FIELD The present invention relates to novel triazine derivatives and herbicides containing them as active ingredients.

BACKGROUND ART Various herbicides have been developed to date, contributing to agricultural productivity and labor savings. However, because certain herbicides have been used for many years, the number of difficult-to-control weeds that are resistant to these herbicides has increased, and the advent of herbicides that have a broad weed-killing spectrum and are effective against these difficult-to-control weeds is desired. In addition, in order to solve the environmental pollution problems caused by conventional herbicides, the development of highly active herbicides is also desired. Furthermore, in order to deal with the uneven occurrence of weeds over a long period of time, the advent of herbicides that have excellent residual activity and a wide application period that is effective even when applied over a wide range of periods, from before weed emergence to the growth period, is also desired.

The present inventors have conducted extensive research to develop a herbicide that is not harmful to paddy rice and that has excellent herbicidal effects on a variety of weeds, from annual to perennial weeds, and have found that herbicides containing triazine compounds as active ingredients are effective (see Japanese Patent Application Laid-Open No. 63-51379, Japanese Patent Application Laid-Open No. 63-22459).
This triazine herbicide is highly active against problematic weeds in paddy rice when applied to flooded soil, even at low doses, without causing any phytotoxicity to the rice. Furthermore, when applied to foliar applications of grasses in field crops, it is highly effective against problematic and highly damaging weeds, without causing any phytotoxicity to the grasses.

However, when this herbicide is applied to the soil of grass field crops before or at the time of weed germination, its activity is still insufficient.

DISCLOSURE OF THE INVENTION The present invention provides a compound comprising: (1) a compound of the general formula [Wherein A is ( ^Y1 and ^Y2 may be the same or different and each represents a methyl group or a methoxy group.)
or (wherein ^Y3 represents a methyl group, a trifluoromethyl group, a methoxy group, or a fluorine atom, and n represents an integer of 0 to 2), ^X1 represents a halogen atom, and ^R1 represents a hydrogen atom, a methyl group, or an ethyl group.] (2) a triazine derivative represented by the general formula [Wherein A is ( ^Y1 and ^Y2 may be the same or different and each represents a methyl group or a methoxy group.)
or (wherein ^Y3 represents a methyl group, a trifluoromethyl group, a methoxy group, or a fluorine atom, and n represents an integer of 0 to 2), ^X1 represents a halogen atom, and ^R1 represents a hydrogen atom, a methyl group, or an ethyl group.

The present inventors have conducted extensive research to find compounds that are not phytotoxic to grass field crops, that exhibit high herbicidal activity against difficult-to-control weeds by both soil and foliar application, and that are effective in flooded soil treatment. As a result, they have found that compounds containing specific haloalkyl groups are effective, and have completed the present invention.

The triazine derivatives of the present invention are novel compounds and can be effectively used as herbicides. When used as upland herbicides, the herbicides of the present invention, which contain the triazine derivatives as active ingredients, have a wider range of suitable application periods than existing upland herbicides, and exhibit high activity against difficult-to-control weeds both in soil treatment before or during weed germination and in foliar treatment during the weed growth period, without causing phytotoxicity to crops. In particular, the herbicides are remarkably effective when applied to soil or foliar areas of grass crops. Furthermore, the herbicides of the present invention are more effective against difficult-to-control weeds and cause less phytotoxicity than existing paddy rice herbicides.

BEST MODE FOR CARRYING OUT THE INVENTION The present invention provides a compound represented by the general formula [Wherein A is ( ^Y1 and ^Y2 may be the same or different and each represents a methyl group or a methoxy group.)
or (wherein ^Y3 represents a methyl group, a trifluoromethyl group, a methoxy group or a fluorine atom, and n represents an integer of 0 to 2), ^X1 represents a halogen atom, and ^R1 represents a hydrogen atom, a methyl group or an ethyl group.], and also provides a herbicide containing the triazine derivative represented by the above general formula [I].

The triazine derivative of the present invention represented by the above general formula [I] can be produced by various methods. Among them, an efficient production method is a method represented by the general formula [wherein A is the same as above, and ^X3 represents a halogen atom] and a salt of an alkylamine represented by the formula By reacting cyanoguanidine represented by the general formula [wherein A and ^X3 are the same as above], and then adding a compound represented by the general formula [wherein ^R1 and ^X1 are the same as above, and ^R2 represents an alkyl group having 1 to 4 carbon atoms.]. According to this method,
The salt of an alkylamine represented by the general formula [I] is reacted with cyanoguanidine to obtain a salt of an alkylbiguanide represented by the general formula [III], which is then reacted with an alkyl ester represented by the general formula [IV], thereby efficiently obtaining the target triazine derivative represented by the general formula [I].

In the reaction of the alkylamine salt represented by the above general formula [II] with cyanoguanidine, the two compounds may be used in approximately equimolar proportions, and the solvent may be a cyclic hydrocarbon such as benzene, decalin, or alkylnaphthalene, or a chlorinated hydrocarbon such as carbon tetrachloride, ethylene dichloride, chlorobenzene, dichlorobenzene, or trichlorobenzene. The reaction temperature is not particularly limited, and the reaction proceeds satisfactorily at low to high temperatures, specifically within the range of 80 to 200°C.

This reaction yields a salt of an alkylbiguanide derivative represented by the general formula [III]. In the method of the present invention,
To this, an alkyl ester of the general formula [IV] The target triazine derivative represented by general formula [I] is produced by reacting the above. This reaction usually proceeds efficiently in a solvent such as an alcohol such as methanol, ethanol, or isopropanol, various ketones, aliphatic hydrocarbons, various ethers, various cyclic hydrocarbons, or chlorinated hydrocarbons, in the presence of a catalyst such as a base at about 10 to 100°C.

The triazine derivatives of the general formula [I] obtained by the above methods are all novel compounds.

The compounds of the present invention have optical isomers and are usually obtained as racemates, but it is also possible to obtain each enantiomer by known methods such as asymmetric synthesis. The compounds of the present invention can be used as herbicides either in the form of racemates or as single optical isomers. Furthermore, the compounds of the present invention can be used as herbicides in the form of salts of inorganic or organic acids.

Furthermore, the triazine derivatives of the general formula [I] are suitable as herbicides because they inhibit the germination and growth of weeds and have high selectivity. Moreover, they are useful not only for soil treatment before the emergence of weeds but also for foliar treatment during the weed growth period, and therefore the suitable application period for the herbicides is wide. The triazine derivatives of the present invention are also useful for the treatment of corn, which is an important upland crop, and corn, which is an important upland crop.
It exhibits excellent herbicidal effects against severe broadleaf weeds such as sickleweed, common morning glory, velvetleaf, clover, chickweed, common persimmon, Japanese knotweed, violet, wild mustard, narrow-leaved amberweed, and Japanese buttercup, as well as severe grass weeds such as crabgrass and black-and-white foxtail, without causing any damage to grass crops such as sorghum, wheat, barley, and oats.

Furthermore, this triazine derivative not only exhibits excellent herbicidal effects against broadleaf weeds such as rice grains, burdock, and Monochoria vaginalis, weeds of the family Celastrus orientalis such as Cyperus sieboldii, and grass weeds such as Echinochloa spp., without causing any phytotoxicity to paddy rice, but also has excellent herbicidal effects against weeds such as Scirpus bulrush, which are currently considered difficult to control.
It also shows excellent herbicidal effect against perennial weeds such as Cyperus serotinus and Sagittaria pygmaea.

Next, the herbicides of the present invention contain the above-mentioned compounds, i.e., the triazine derivatives represented by general formula [I], as active ingredients, and these compounds can be mixed with a liquid carrier such as a solvent or a solid carrier such as fine mineral powder, and formulated into wettable powders, emulsifiable concentrates, dusts, granules, flowables, liquids, etc. When formulating the herbicides, surfactants such as emulsifiers, dispersants, spreading agents, suspending agents, penetrating agents, stabilizers, and other adjuvants may be added as desired.

When the herbicide of the present invention is used in the form of a wettable powder, the herbicide is usually used in an amount of 10 to 150 ml of the above-mentioned triazine derivative of the present invention as an active ingredient.
55% by weight, solid carrier 40-88% by weight, and surfactant 2-
When used in the form of an emulsion or flowable, the triazine derivative of the present invention is usually blended in an amount of 5 to 50% by weight as the active ingredient, 35 to 90% by weight of the solvent, and 5 to 15% by weight of the surfactant and other adjuvants.

On the other hand, when used in the form of a powder, the active ingredient is usually 1 to 15% by weight of the triazine derivative of the present invention, and the solid carrier is 85% by weight.
The composition may be prepared by blending the above components at a ratio of 100% to 99% by weight.
When used in the form of granules, the triazine derivative of the present invention may be mixed in the proportions of 0.1-15% by weight as the active ingredient, 80-97.9% by weight of the solid carrier, and 2-5% by weight of the surfactant, and the solid carrier may be a fine mineral powder, and examples of the fine mineral powder include oxides such as diatomaceous earth and slaked lime, phosphates such as apatite, sulfates such as gypsum, talc, pyroferrite, clay, kaolin,
Examples include silicates such as bentonite, acid clay, white carbon, quartz powder, and silica stone powder.

The liquid carrier may be a paraffinic or naphthenic hydrocarbon such as kerosene, mineral oil, or spindle oil; an aromatic hydrocarbon such as benzene, toluene, or xylene; a chlorinated hydrocarbon such as o-chlorotoluene, trichloromethane, or trichloroethylene; an alcohol such as cyclohexanol, amyl alcohol, or ethylene glycol; an alcohol ether such as ethylene glycol monomethyl ether or ethylene glycol monoethyl ether; isophorone;
Ketones such as cyclohexanone and cyclohexenyl-cyclohexanone, butyl cellosolve, dimethyl ether,
Examples include organic solvents such as ethers such as methyl ethyl ether, esters such as isopropyl acetate, benzyl acetate, and methyl phthalate, amides such as dimethylformamide, nitriles such as acetonitrile and propionitrile, sulfoxides such as dimethyl sulfoxide, and mixtures thereof, as well as water.

Furthermore, surfactants include anionic types (alkylbenzene sulfonate, alkyl sulfonate, lauric acid amide sulfonate, etc.), nonionic types (polyoxyethylene octyl ether, polyethylene glycol laurate, sorbitan alkyl ester, etc.), cationic types (dimethyl lauryl benzyl ammonium chloride, lauryl amine, stearyl trimethyl ammonium chloride, etc.), and zwitterionic types (amino acids,
betaine, etc.) can also be used.

Furthermore, the compounds of the present invention can be used in combination with polymeric compounds and adjuvants such as sodium alginate, carboxymethylcellulose, carboxyvinyl polymer, gum arabic, and hydroxypropylmethylcellulose in order to improve the properties of the formulation and enhance the herbicidal effect.

The novel triazine derivatives of the present invention represented by the general formula [I] are highly effective as non-phytotoxic, highly selective herbicides when applied to field crops such as corn, sorghum, wheat, barley, oats, etc. by soil or foliar application before or after germination of weeds. They are also highly effective against not only annual but also perennial weeds, and are extremely useful as non-phytotoxic, highly selective herbicides for paddy rice.

The herbicide of the present invention is used in an amount of 0.1 to 1000 g of the active ingredient per 10 ares.
When spraying on plant foliage, the amount is about 1 to 10,000 ppm, preferably 10 to 10
Dilute to 00 ppm and apply.

The herbicide of the present invention can contain other herbicidal ingredients in combination with the triazine derivative represented by formula [I] as an active ingredient. Such other herbicidal ingredients include conventionally commercially available herbicides, such as phenoxy herbicides, diphenyl ether herbicides, triazine herbicides, urea herbicides, carbamate herbicides, thiolcarbamate herbicides, acid anilide herbicides, pyrazole herbicides, phosphate herbicides,
Examples include sulfonylurea herbicides, nitrile herbicides, dinitroaniline herbicides, imidazolinone herbicides, and oxadiazon.

Furthermore, the herbicide of the present invention can be used in combination with insecticides, fungicides, plant growth regulators, fertilizers, etc., if necessary.

[Examples] Next, the present invention will be described in more detail using examples.

Preparation Example 1 0.92 g (40 mmol) of sodium was slowly added to 20 ml of dry methanol to generate sodium methoxide, and then 2-(3',5'-dimethylphenoxy)isopropylbiguanide hydrochloride (20 mmol) was added as raw material I.
(described in JP-A-63-264465) was added and the mixture was stirred at room temperature for 30 minutes.
The mixture was stirred for 1 minute. Then, α-fluoro, α
4.80 ml (40 mmol) of ethyl methylpropionate was added dropwise, and the mixture was stirred at room temperature for 10 hours.
The contents were poured into 100 ml of water and extracted three times with 50 ml of ethyl acetate. The ethyl acetate layer was dried over anhydrous sodium sulfate, and the ethyl acetate was distilled off under reduced pressure. The residue was purified by silica gel column chromatography (eluent: hexane/ethyl acetate = 4/1), and then recrystallized from hexane-ethyl ether to give white 2-amino-4-
[2-(3',5'-dimethylphenoxy)isopropylamino]-6-(α-fluoroisopropyl)-s-triazine (Compound 1) was obtained.
The analytical results, structural formulas, etc. are shown in Tables 1 to 3.

Preparation Examples 2 to 29 In Preparation Example 1, alkylbiguanide hydrochlorides shown in Table 1 (JP-A-2002-100626) were used instead of 2-(3',5'-dimethylphenoxy)isopropylbiguanide hydrochloride as raw material I.
20 mmol of α-(2-methyl-2-propanol) (described in Japanese Patent Application Laid-Open No. 63-51379 and Japanese Patent Application Laid-Open No. 63-264465) was used as raw material II.
Compounds 2 to 29 were obtained by the same procedure as in Preparation 1, except that 20 mmol of the esters shown in Table 1 were used instead of fluoro, α-methylpropionic acid ethyl ester. The yield, analytical results, structural formulas, etc. of these compounds are shown in Tables 1 to 3.

Next, the formulation method will be specifically explained using formulation examples. In the following formulation examples, "parts" means % by weight.

Formulation Example 1 Wettable Powder The compound of Preparation Example 1 20 parts, diatomaceous earth 62 parts, white carbon 15 parts, sodium alkylbenzenesulfonate 2 parts, sodium ligninsulfonate 1 part were mixed, uniformly mixed and pulverized to obtain 100 parts of a wettable powder.

Formulation Example 2: Emulsifiable concentrate 40 parts of the compound from Preparation Example 2 20 parts xylene 20 parts dimethylformamide 20 parts Sorpol 2806B (Toho Chemical Industry, surfactant) The above ingredients were uniformly dissolved and mixed to obtain 100 parts of an emulsifiable concentrate.

Formulation Example 3: Powder 2 parts of the compound from Preparation Example 3 20 parts of diatomaceous earth 78 parts of talc The above ingredients were mixed and ground to obtain 100 parts of a powder.

Formulation Example 4 Granules The compound of Preparation Example 4 1 part Bentonite 30 parts Talc 66 parts Sodium ligninsulfonate 3 parts The above ingredients were thoroughly mixed, uniformly mixed and pulverized, water was added and the mixture was kneaded well, then granulated and dried to obtain 100 parts of granules.

Formulation Example 5 Flowable The compound of Preparation Example 5 25 parts, methylcellulose 0.3 parts, colloidal silica 1.5 parts, sodium ligninsulfonate 1 part, polyoxyethylene nonylphenyl ether 2 parts, water 70.2 parts were thoroughly mixed and dispersed, and the slurry mixture was wet-pulverized to obtain 100 parts of a stable flowable.

Formulation Example 6: 97 parts of clay (trade name: Zieklite, manufactured by Zieklite Kogyo Co., Ltd.) as a wettable powder carrier, 1.5 parts of alkylarylsulfonate (trade name: Neopelex, manufactured by Kao Atlas Co., Ltd.) as a surfactant, and 1.5 parts of nonionic and anionic surfactants (trade name: Sorpol 800A, manufactured by Toho Chemical Industry Co., Ltd.)
1.5 parts of PEG-1000 (manufactured by PEG-1000) were uniformly crushed and mixed to obtain a carrier for wettable powders.

90 parts of this carrier for wettable powders and 10 parts of the triazine derivatives obtained in the above Production Examples 1 to 29 were uniformly ground and mixed to give wettable powders.

Examples 1 to 29: Field soil treatment test Field soil was filled into 1/2000 are Wagner pots and seeds of Digitaria adscendens, Black-eye grass, Abutilon veitchii, Persian violet, Polygonum vulgare, Amaranth, Cleaver, Wheat, Barley, Corn and Sorghum were sown uniformly on the surface.

Thereafter, before the wheat, barley, corn, sorghum and weeds germinate, a predetermined amount of the diluted solution of the herbicide obtained in Formulation Example 6 above is uniformly applied to the soil surface, and the pots are left in a greenhouse and water is removed as needed.

The herbicidal effect and phytotoxicity to wheat, barley, corn and sorghum were investigated 30 days after application of the chemical solution, and the results are shown in Table 4.
The dosage was set to 25-100g/10a in terms of the amount of active ingredient.
The phytotoxicity and herbicidal effects on wheat, barley, corn and sorghum were measured by measuring the air-dry weight of each and expressed as follows:

Comparative Examples 1 to 4 In Example 1, the triazine derivative A represented by the following formula was used instead of the triazine derivative prepared in Preparation Example 1.
The same procedure as in Example 1 was carried out except that compounds C (described in JP-A No. 63-264465) or D (described in JP-A No. 63-51379) were used. The results are shown in Table 4.

Examples 30 to 58 Foliage Treatment Tests Weed seeds of velvetleaf, burdock, lily of the valley, sickleweed, morning glory, cleaver, and persea gracilis, as well as corn, sorghum, wheat, barley, and
Barley seeds were sown, covered with soil, and grown at room temperature. A predetermined amount of the herbicide obtained in Formulation Example 6 was suspended in water and sprayed evenly onto the foliage at a rate equivalent to 100/10 ares when the weeds were at the 1- to 2-leaf stage and when the crop was at the 3-leaf stage. The plants were then grown at room temperature, and 20 days after treatment, the crop damage and herbicidal effect were evaluated according to the following evaluation criteria. The results are shown in Table 5.

(Criteria for evaluation) Degree of herbicidal effect Herbicidal effect (herbicidal rate) 0 Less than 5% (almost no effect) 1 5-20% 2 20-40% 3 40-70% 4 70-80% 5 90% or more (almost complete death) However, the above herbicidal rate was calculated by measuring the fresh weight of the aboveground parts of the treated area and the untreated area and using the following formula.

Phytotoxicity Level: 0: No phytotoxicity to the crops was observed. 1: Almost no phytotoxicity to the crops was observed. 2: Slight phytotoxicity to the crops was observed. 3: Phytotoxicity to the crops was observed. 4: Significant phytotoxicity to the crops was observed. 5: Almost all of the crops died. Comparative Examples 5-8: In Example 30, the triazine derivative A shown in Comparative Examples 1-4 was used instead of the triazine derivative prepared in Preparation Example 1.
The same procedure as in Example 30 was carried out except that B, C or D was used. The results are shown in Table 5.

Examples 59 to 87: Flooded soil treatment test Paddy field soil was filled into 1/15,500 are porcelain pots, and seeds of barnyard grass, Cyperus spp., broadleaf weeds (Robinia orbicularis and Monochoria vaginalis), and bulrush were sown evenly on the surface. Then, tubers of Cyperus serotinus and Sagittaria pygma were transplanted, and rice plants at the two-leaf stage were transplanted.

Thereafter, when the weeds germinated, a predetermined amount of the diluted solution of the herbicide obtained in Formulation Example 6 was applied dropwise evenly to the water surface for treatment, and the pot was then left at room temperature and the water was removed as appropriate.

The herbicidal effect and rice phytotoxicity were investigated 20 days after treatment, and the results are shown in Table 6. The dosage is shown as the amount of active ingredient per 10 ares. Rice phytotoxicity and herbicidal effect were measured by air-dry weight and expressed as follows:

Degree of phytotoxicity: Phytotoxicity to paddy rice (compared to untreated area) 0 100% 1 95-99% 2 90-94% 3 80-89% 4 60-79% 5 50-59% Degree of herbicidal effect: Herbicidal effect (compared to untreated area) 0 100% 1 61-99% 2 21-60% 3 11-20% 4 1-10% 5 0% Comparative Examples 9-12: In Example 59, the triazine derivative A shown in Comparative Examples 1-4 was used in place of the triazine derivative produced in Production Example 1.
The same procedure as in Example 59 was carried out except that B, C or D was used. The results are shown in Table 6.

[0033] The triazine derivatives of the present invention are novel compounds and can be effectively used as herbicides. Compared with existing herbicides for upland fields, herbicides of the present invention containing the triazine derivatives as active ingredients are more effective against weeds, including those that are difficult to control, without causing phytotoxicity to crops. In particular, soil or foliar application in fields of grass crops is extremely effective. Furthermore, the herbicides of the present invention are more effective against difficult-to-control weeds and cause less phytotoxicity than existing herbicides for paddy rice.

Claims (2)

[Claims] [Claim 1] General formula [Wherein A is ( ^Y1 and ^Y2 may be the same or different and each represents a methyl group or a methoxy group.)
or (wherein ^Y3 represents a methyl group, a trifluoromethyl group, a methoxy group or a fluorine atom, and n represents an integer of 0 to 2), ^X1 represents a halogen atom, and ^R1 represents a hydrogen atom, a methyl group or an ethyl group. [Claim 2] General formula [Wherein A is ( ^Y1 and ^Y2 may be the same or different and each represents a methyl group or a methoxy group.)
or (wherein ^Y3 represents a methyl group, a trifluoromethyl group, a methoxy group, or a fluorine atom, and n represents an integer of 0 to 2), ^X1 represents a halogen atom, and ^R1 represents a hydrogen atom, a methyl group, or an ethyl group.