JPS6261026B2 - - Google Patents

Description

[Detailed description of the invention]

The present invention is based on the general formula [] (In the formula, The present invention relates to a urea derivative represented by (or a methoxy group; a double bond indicates a trans isomer), a method for producing the same, and a selective herbicide comprising the compound. The present inventors conducted intensive research to develop a so-called highly selective herbicide that is highly safe for crops and has high herbicidal activity against weeds. As a result, the compound represented by the general formula [] The present invention has been completed by discovering a herbicide with excellent characteristics, such as showing a high degree of selectivity between weeds and weeds, and having extremely low toxicity to humans, livestock, and fish and shellfish. The urea compounds that are part of the composition of the compounds of the present invention are widely known as herbicides, but it is also widely known that urea derivatives are difficult to select between crops and weeds due to their action characteristics. There is. Examples of urea-based compounds that are already commercially available include N'-4-chlorophenyl-N,N-dimethylurea (common name: Monyuron), N'-3,4-
Dichlorophenyl-N,N-dimethylurea (generic name: diuron), N'-3,4-dichlorophenyl-N-methoxy-N-methylurea (generic name:
Linyuron) etc. are known. However, while these herbicides are highly effective against weeds, they can also be harmful to crops, so in reality, their use must be limited to specific crops in limited situations. It is. Further, triazine compounds are also widely known as herbicides, but like the urea herbicides mentioned above, it is also widely known that they have low selectivity due to their action characteristics. For example, 2,4-bis(ethylamino)-6-methylthio-1,3,5-triazine (common name: simetrine) is a triazine herbicide that is absorbed slowly through the roots, so it is especially effective against broadleaf herbicides. It is relatively widely used to target weeds. However, in actual use, it is subject to considerable limitations and requires sufficient caution. Particularly when used in rice paddies, chemical damage occurs at high temperatures combined with flooding conditions, so use in warm regions is severely restricted. As is clear from the test examples, the compound of the present invention represented by the general formula [] shows almost no phytotoxicity to cultivated crops, regardless of the treatment method.
Furthermore, it exhibits extremely strong herbicidal activity against weeds and has remarkable selective herbicidal activity. The compounds of the present invention represented by the general formula [] are all new compounds and can be produced by the method shown below. 1 General formula [] (In the formula, X and n have the same meanings as above,
Y represents a halogen atom. A double bond indicates a trans isomer. ) and the general formula [] (In the formula, R has the same meaning as above.) It can be obtained by reacting a urea derivative represented by the following formula. The reaction can be carried out in a suitable solvent using a suitable acid acceptor to obtain a compound represented by the general formula [] in high yield. The solvents mentioned here include, for example, hydrocarbons such as benzene and toluene, ethers such as diethyl ether, tetrahydrofuran, and dioxane, alcohols such as methanol and ethanol, and organic solvents such as chloroform, acetic acid ethyl ester, and dimethylformamide. A mixed solvent of these or water or a mixed solvent with water can also be used if necessary. As the acid acceptor, for example, organic compounds such as pyridine and triethylamine, and inorganic compounds such as caustic soda, caustic potash, and soda carbonate are used. The reaction generally proceeds at room temperature, but depending on the conditions, it may be carried out under cooling or heating as appropriate. The reaction time is generally completed in 1 to 8 hours. After the reaction is completed, the desired product can be obtained by separating and purifying the product using conventional methods. 2 General formula [] (In the formula, X and n have the same meanings as above.)
Phenol derivatives represented by and general formula [] (In the formula, Y and R have the same meanings as above.
A double bond indicates a trans isomer. ) The compound represented by the general formula [] is obtained in high yield by reacting the urea derivative represented by the formula []. The reaction is carried out using a suitable solvent or acid acceptor. When carrying out this reaction, the solvent may be, for example, hydrocarbons such as benzene and toluene, ethers such as diethyl ether, ether, tetrahydrofuran, dioxane, etc., halogenated hydrocarbons such as chloroform, alcohols such as methanol, ethanol, etc. Organic solvents such as ester-based acetic acid ethyl ester, dimethylformamide, etc., or mixed solvents thereof, and if necessary, water or a mixed solvent with water can also be used. As the acid acceptor, for example, organic compounds such as pyridine and trimethylamine, and inorganic compounds such as caustic soda, caustic potash, and soda carbonate are used. Although the reaction proceeds at room temperature, it can proceed smoothly by carrying out the reaction under cooling or heating as the case may be. The reaction time can be completed in 1 to 8 hours if appropriate conditions are selected. After the reaction is completed, the target product is obtained by separating and purifying it by conventional methods. 3 General formula [] (In the formula, X and n have the same meanings as above.
A double bond indicates a trans isomer. ) Aniline derivatives represented by the general formula [] (In the formula, Y and R have the same meanings as above.)
The compound represented by the general formula [] is obtained in high yield by reacting the carbamic acid halide derivative represented by the formula []. The reaction is carried out using a suitable solvent or acid acceptor. When carrying out this reaction, the solvent may be, for example, hydrocarbons such as benzene, toluene, xylene, etc., halogenated hydrocarbons such as dichloromethane, chloroform, etc., ethers such as diethyl ether, tetrahydrofuran, dimethylformamide, etc., or these solvents. The process proceeds smoothly when carried out in a mixed solvent. Examples of acid acceptors include organic compounds such as pyridine and triethylamine, caustic soda, caustic potash,
By using inorganic compounds such as soda carbonate, the desired product can be obtained in high yield. The reaction proceeds smoothly at room temperature, but in some cases the reaction can be carried out under heating. Although the reaction time depends on the selection of conditions, the reaction is completed in 1 to 8 hours. After the reaction is completed, the target product is obtained by separating and purifying it by conventional methods. 4 General formula [] (In the formula, X and n have the same meanings as above.
A double bond indicates a trans isomer. ) Phenyl isocyanate derivatives represented by the general formula [] By reacting the amine derivative represented by (wherein R has the same meaning as above), the compound represented by the general formula [] is obtained in high yield. When carrying out this reaction, the solvent may be, for example, hydrocarbons such as benzene and toluene, halogenated hydrocarbons such as dichloromethane and chloroform, ethers such as diethyl ether, tetrahydrofuran, dioxane, dimethylformamide, etc., or these solvents. The process proceeds smoothly when carried out in a mixed solvent. Although the reaction proceeds smoothly at room temperature, better results can be obtained by carrying out the reaction under cooling or heating in some cases. The reaction time is 1 to 8 hours, depending on the selection of conditions. After the reaction is completed, the desired product can be obtained by separating and purifying it by conventional methods. 5 Among the compounds represented by the general formula [], R
When is a methoxy group, the general formula [] (In the formula, X and n have the same meanings as above.
A double bond indicates a trans isomer. ) The compound represented by the general formula [] is obtained in high yield by methylating the urea derivative represented by the formula []. Examples of the methylating agent include dimethyl sulfate, methyl iodide, and diazomethane. Reaction conditions vary depending on each methylating agent, such as reaction solvent, reaction aid, reaction temperature, reaction time, etc., but satisfactory results can be obtained using general methylation methods using widely known methylating agents. get. Next, a synthesis example will be shown and explained in detail. Synthesis Example 1 Add 4-(4-chloro-2-methylphenyloxy) to a solution of 0.78 g of potassium hydroxide and 1.8 g of N'-4-hydroxyphenyl-N,N-dimethylurea dissolved in 30 ml of ethyl alcohol. -Add 2.3g of 2-trans-butenyl chloride and
After reacting at ℃ for 4 hours with stirring, the mixture was diluted with water and extracted with acetic acid ethyl ester. After distilling off the solvent under reduced pressure and recrystallizing the residue from ethanol, N′-
3.1 g of 4-[4-(4-chloro-2-methylphenyloxy)-2-trans-butenyloxy-phenyl-N,N-dimethylurea was obtained. Melting point 122-123℃ (Compound No. 32) Elemental analysis value: C ₂₀ H ₂₃ ClN ₂ O ₃ (molecular weight 374.87) C H N Calculated value (%) 64.08 6.18 7.47 Actual value (%) 64.29 6.23 7.49 Synthesis example 2 Hydroxylation Potassium 0.78g and N'-3-hydroxyphenyl-N-methyl-N-methoxyurea 2.0g
was dissolved in 40 ml of ethyl alcohol, and 4-(2,6-dimethylphenyloxy)-2-
After adding 2.1 g of trans-butenyl chloride, the reaction mixture was heated and stirred at 60 to 70°C for 5 hours, and after the reaction was completed, the mixture was diluted with water and extracted with acetic acid ethyl ester. The solvent is distilled off under reduced pressure. The oil thus obtained is subjected to silica gel column chromatography, and the target product is separated using chloroform. The main fraction obtained was taken and the solvent was distilled off under reduced pressure to give N′-3-[4-(2,6
-dimethylphenyloxy)-2-trans-
butenyloxy]-phenyl-N-methyl-
3.0 g of N-methoxyurea was obtained as an oil. (Compound No. 138) Elemental analysis value: C ₂₁ H ₂₆ N ₂ O ₄ (molecular weight 370.45) C H N Calculated value (%) 68.09 7.07 7.56 Actual value (%) 68.33 7.15 7.40 NMR absorption spectrum (δ. in CDCl ₃ ) 2.24 (6H, s), 3.14 (3H, s), 3.71
(3H, s), 4.30 (2H, m), 4.53 (2H,
m), 6.05 (2H, m), 6.48-7.31 (7H),
7.65 (1H, bs). Synthesis Example 3 N′-3-(4-chloro-2-trans-butenyloxy)-phenyl-N- 2.9 g of methyl-N-methoxyurea was added, and the reaction mixture was heated and stirred at 50° C. for 4 hours. After the reaction was completed, the mixture was diluted with water and extracted with ethyl acetate. The solvent was distilled off under reduced pressure, and the resulting residue was recrystallized from a mixed solvent of ethyl acetate and n-hexane to give N'-3-[4-
3.2 g of (2,4-dichlorophenyloxy)-2-trans-butenyloxy]-phenyl-N-methyl-N-methoxyurea was obtained. Melting point 91~
92℃ (Compound No. 98) Elemental analysis value: C ₁₉ H ₂₀ Cl ₂ N ₂ O ₄ (molecular weight 411.28) C H N Calculated value (%) 55.49 4.90 6.81 Actual value (%) 55.53 4.90 6.70 Synthesis example 4 4-[ 4-(4-chlorophenyloxy)-2
-trans-butenyloxy]-aniline 2.7g
and 1.2 g of triethylamine in tetrahydrofuran.
The solution dissolved in 30 ml was cooled with ice, and 1.3 g of dimethyl-carbamic acid chloride was slowly added dropwise while stirring. After the dropwise addition was completed, the mixture was stirred for 30 minutes and then further stirred at room temperature for 2 hours. Then, the triethylamine hydrochloride was separated and the solvent was distilled off under reduced pressure. When the obtained residue is recrystallized with ether, N′-4-[4-
(4-chlorophenyloxy)-2-trans-
3.0 g of butenyloxy]-phenyl-N,N-dimethylurea was obtained. Melting point 144-145℃ (Compound No. 4) Elemental analysis value: C ₁₉ H ₂₁ ClN ₂ O ₃ (molecular weight 360.84) C H N Calculated value (%) 63.24 5.88 7.76 Actual value (%) 63.18 5.92 7.88 Synthesis example 5 3- 3.3 g of [4-(4-chloro-2-methylphenyloxy)-2-trans-butenyloxy]-phenyl isocyanate was dissolved in 30 ml of tetrahydrofuran, and the solution was stirred under ice cooling.
Add dropwise to 1 g of dimethylamine 50% aqueous solution. After the dropwise addition was completed, stirring under ice cooling was continued for 30 minutes. After that, the mixture was further stirred at room temperature for 2 hours, and then the solvent was distilled off under reduced pressure. When the obtained residue is recrystallized from acetic acid ethyl ester-n-hexane mixed solvent,
2.9 g of N'-3-[4-(4-chloro-2-methylphenyloxy)-2-trans-butenyl-oxy]-phenyl-N,N-dimethylurea was obtained. Melting point 116-118℃ (Compound No. 80) Elemental analysis value: C ₂₀ H ₂₃ ClN ₂ O ₃ (molecular weight 374.87) C H N Calculated value (%) 64.08 6.18 7.47 Actual value (%) 63.97 6.21 7.51 Synthesis example 6 3- A solution of 3.1 g of [4-(2,4-dimethylphenyloxy)-2-trans-butenyloxy]-phenyl isocyanate dissolved in 10 ml of methylene chloride was mixed with 0.8 g of hydroxylamine hydrochloride and 0.5 g of hydroxide. Add dropwise to an aqueous solution containing dissolved sodium while cooling with ice and stirring. After the addition was complete, stir for 30 minutes and then stir for 2 more minutes while returning to room temperature.
Continue stirring for an hour. After the reaction is completed, it is diluted with water and the resulting precipitate is overdried. The hydroxylurea derivative thus obtained was dissolved in 50 ml of a mixed solvent of benzene-methanol (1:1), mixed with 1 ml of a 10N aqueous sodium hydroxide solution and 1.3 g of dimethyl sulfate.
Add dropwise while cooling on ice and stirring. After stirring for 30 minutes after completion of the dropwise addition, stirring was continued for an additional 2 hours while returning to room temperature. After the reaction is completed, the mixture is diluted with water and extracted with benzene. The solvent was distilled off under reduced pressure, and the resulting residue was recrystallized from a mixed solvent of acetic acid ethyl ester-n-hexane to give N'-3-[4-(2,4-dimethylphenyloxy)-2-trans- 2.6 g of butenyloxy]-phenyl-N-methyl-N-methoxyurea was obtained. Melting point: 84.5-85°C (compound number 104) Elemental analysis value: C ₂₁ H ₂₆ N ₂ O ₄ molecular weight 370.45 C H N Calculated value (%) 68.09 7.07 7.56 Actual value (%) 68.33 7.15 7.40 Next, the thus obtained Representative examples of the compounds of the present invention represented by the above general formula [] are shown in Table 1.
Note that the present invention is not limited only to these exemplified compounds. In Table 1, 2 to 6 in the substituent X column indicate the substitution positions on the benzene ring of the compound represented by the above general formula [], and the bond position column shows the substitution positions of the compound represented by the above general formula

[Formula] Indicates the bonding position of the group. Furthermore, among the compounds of the present invention, the NMR absorption spectrum values of the compounds obtained as oily substances using conventional separation and purification methods are shown in Table 2. In addition, Et in Table 1 below is −C ₂ H ₅ and Pr is −
_{C3H7 ,} Bu represents _-C4H9 , _and Am _{represents -C5H11} .

【table】

【table】

【table】

【table】

【table】

【table】

【table】

[Table] In carrying out the present invention, one or a mixture of two or more of the compounds represented by the general formula
50-2000g per are, preferably 100-1000g
Although it is appropriate to use the drug at a ratio of 1, it goes without saying that the dosage can be adjusted depending on the circumstances of the actual situation. When actually used, the compound of the present invention can be used directly as it is, but depending on the purpose of use, one or more compounds represented by the above general formula [] may be dissolved in a liquid carrier. or by dispersing it or adsorbing it with a suitable solid carrier (e.g. diluent, filler, etc.) and, if desired, with an emulsifying agent, dispersing agent, suspending agent, or spreading agent. , a penetrating agent, a stabilizer, etc. are added to form a dosage form such as a wettable powder, emulsion, granule, powder, or tablet. Examples of the liquid carrier (solvent) mentioned here include:
Alcohols such as methyl alcohol, ethyl alcohol, and ethylene glycol; ketones such as acetone and methyl ethyl ketone; ethers such as dioxane, tetrahydrofuran, and cellosolve; hydrocarbons such as benzene, toluene, xylene, hexane, kerosene, kerosene, naphtha, and methyl Organic solvents such as naphthalene, esters such as ethyl acetate and butyl acetate, organic bases such as pyridine and picoline, dimethylformamide, and acetonitrile are suitable, and one or a mixture of two or more of these may be used. Examples of solid carriers (diluents, fillers, etc.) include mineral powders such as kaolin, bentonite, acid clay, clay, talc, diatomaceous earth, mica powder, etc., vegetable powders such as soybean powder, wheat flour, wood flour, etc. Furthermore, alumina, activated carbon, etc. can also be used, and one or a mixture of two or more of these can be used. emulsifier,
Anionic, cationic, nonionic, and amphoteric surfactants can be used as dispersants, penetrants, and spreading agents. If desired, casein, gelatin, starch, sodium alginate, etc. can be used as adjuvants. When formulating the compound of the present invention, the ratio of active ingredients can be set freely, but it is generally 5 to 5.
A content of 90% is suitable. Furthermore, depending on the purpose of use, the compound of the present invention can be used in combination with other herbicides, fungicides, insecticides, plant growth regulators, fertilizers, and the like. Next, an explanation will be given with reference to examples, but the compounds, carriers, adjuvants, and proportions used are not limited to these examples. In addition, the composition ratio of the components in this example shows parts by weight. Example 1 (Wettable powder) Compound No. 32 50 parts Sodium lignin sulfonate 1 part Polyoxyethylene alkylaryl ether 4 parts Clay 45 parts These components were mixed until uniform, ground, and used as a wettable powder. . Example 2 (Emulsion) Compound No. 102 20 parts Alkylbenzene sulfonate 3 parts Polyoxyethylene alkylaryl ether 10 parts Xylol 67 parts These components are mixed until uniform, dissolved, and used as an emulsion. Example 3 (Granules) Compound No. 4 6 parts Bentonite 30 parts Sodium alkyl sulfate 1.5 parts Clay 62.5 parts These components were mixed until uniform, kneaded, and granulated using a normal granulation method to produce granules. used as Example 4 (Powder) Compound No. 24 7 parts Clay 93 parts These components are mixed until uniform and used as a powder. Next, the effects of the compounds of the present invention will be explained using test examples. Test example 1 A 1/5000 are polyethylene pot was filled with paddy soil (clay loam), and a field of wildflowers, snails,
Sow each broad-leaved weed seed 2 cm above the surface, and at the same time
Two paddy rice plants in the leaf stage were planted at a depth of 2 cm, and 3
flooded to cm. Simultaneously with weed germination, a predetermined amount of a hydrating powder of each test compound prepared according to the formulation according to Example 1 was weighed out, diluted in 10 ml of water per pot, and dropped onto the water surface. Thereafter, they were grown in a glass room, and three weeks after treatment, the herbicidal effect and paddy rice damage were investigated. The results are shown in Table 3. In addition, the numerical values in the table indicate paddy rice phytotoxicity and herbicidal effects, and are specifically as follows.

【table】

【table】

【table】

【table】

【table】

【table】

【table】

【table】

[Table] Test Example 2 Fill a 1/5000 are polyethylene pot with upland soil (clay loam), sow seeds of rice, wheat, barnyard grass, radish, and blueberry, cover with 1 cm of soil, and grow in a glass room. did. Thereafter, when rice had developed its two-leaf stage, wheat had developed its three-leaf stage, and radish and Japanese radish had developed their first true leaves, a predetermined amount of the hydrating agent of the compound of the present invention prepared according to the formulation according to Example 1 was weighed. The mixture was diluted in 2 ml of water per pot and sprayed over the entire surface of the stems and leaves. Two weeks after the treatment, the degree of phytotoxicity and herbicidal effect on each test plant was investigated. The results are shown in Table 4. Note that the numerical values in the table conform to the interpretation shown in Test Example 1.

【table】

【table】

【table】

Claims (1)

[Claims] 1. General formula (In the formula, X represents a halogen atom, an alkyl group, or a trifluoromethyl group, n represents an integer from 0 to 3, and when n is 2 or 3, X may be the same or different. or a methoxy group.The double bond indicates a trans isomer). 2 General formula (In the formula, X represents a halogen atom, an alkyl group, or a trifluoromethyl group, n represents an integer from 0 to 3, and when n is 2 or 3, X may be the same or different. (The double bond indicates the trans isomer.) and the general formula (In the formula, R represents a methyl group or a methoxy group.) A general formula characterized by reacting with a urea derivative represented by (In the formula, X, n and R have the same meanings as above. The double bond indicates a trans form.) A method for producing a urea derivative represented by the formula: 3 General formula (In the formula, X represents a halogen atom, an alkyl group, or a trifluoromethyl group, n represents an integer from 0 to 3, and when n is 2 or 3, X may be the same or different.) Phenol derivatives and general formula (In the formula, Y represents a halogen atom, R represents a methyl group or a methoxy group, and the double bond represents a trans form.) (In the formula, X, n and R have the same meanings as above. The double bond indicates a trans form.) A method for producing a urea derivative represented by the formula: 4 General formula (In the formula, X represents a halogen atom, an alkyl group, or a trifluoromethyl group, n represents an integer from 0 to 3, and when n is 2 or 3, X may be the same or different. (Indicates trans isomer.)
Aniline derivatives and general formula represented by (In the formula, Y represents a halogen atom and R represents a methyl group or a methoxy group.) (In the formula, X, n and R have the same meanings as above. The double bond indicates a trans form.) A method for producing a urea derivative represented by the formula: 5 General formula (In the formula, X represents a halogen atom, an alkyl group, or a trifluoromethyl group, n represents an integer from 0 to 3, and when n is 2 or 3, X may be the same or different. (Indicates trans isomer.)
Phenyl isocyanate derivatives represented by and general formula A general formula characterized by reacting an amine derivative represented by (wherein R represents a methyl group or a methoxy group) (In the formula, X, n and R have the same meanings as above. The double bond indicates a trans form.) A method for producing a urea derivative represented by the formula: 6 General formula (In the formula, X represents a halogen atom, an alkyl group, or a trifluoromethyl group, n represents an integer from 0 to 3, and when n is 2 or 3, X may be the same or different. (Indicates trans isomer.)
A general formula characterized by methylating a urea derivative represented by (In the formula, X and n have the same meanings as above. R represents a methoxy group. The double bond represents a trans form.) A method for producing a urea derivative represented by the formula: 7 General formula (In the formula, or a methoxy group.The double bond indicates a trans form.) A selective herbicide characterized by containing a urea derivative represented by the following as an active ingredient.