JPS6357423B2 - - Google Patents

Description

[Detailed description of the invention]

The present invention relates to a diphenyl ether compound useful as a herbicide, a herbicidal composition containing the same, and a method for using the same. According to the invention, the general formula (): [In the formula, A is hydrogen, _NO2 , N=N- _CF3 ,
NH ₂ , NHOH, -N ₂ ⁺ , NHCOR ¹ (R ¹ represents an alkyl group, CF ₃ or a mono- or dialkylamino group), alkyl group, NHSO ₂ R ² (R ² represents an alkyl group), -SCN , N ₃ , CF ₃ or

[Formula]; B represents hydrogen, fluorine, chlorine, an alkylsulfinyl group, or _NO2 ; C represents hydrogen, halogen, or an alkyl group; D represents hydrogen, halogen, _CF3, or a nitro group; E represents hydrogen, halogen or _CF3 ;
F represents hydrogen, fluorine or chlorine; R is a group -
CONHSO ₂ R ³ (R ³ is a phenyl or indanyl group optionally substituted with one or more halogen atoms, an alkyl group or a nitro group; or one or more chlorine or one or more optionally substituted with an alkoxycarbonyl substituent,
(representing an alkyl group having 1 to 4 carbon atoms) is provided. In alkyl groups or groups containing one or more alkyl groups, such as mono- and dialkyl groups or alkoxy groups, the alkyl group can be a lower alkyl group having 1 to 6 carbon atoms. One group of compounds of the present invention is characterized in that in the general formula (), A is hydrogen or a nitro group; B is a nitro group; C is hydrogen; D is fluorine, chlorine, bromine, iodine or CF ₃ ; E is hydrogen; F is hydrogen, fluorine or chlorine;
R is a CONHSO ₂ R ³ group (R ³ is an alkyl group having 1 to 4 carbon atoms optionally substituted with one or more chlorine or one or more alkoxycarbonyl substituents) Consists of compounds. Another group of compounds of the present invention is that in the general formula (), A is a methyl group or a trifluoromethyl group; B is fluorine or chlorine;
C is hydrogen; D is fluorine, chlorine, bromine, iodine or _CF3 ; E is hydrogen, F is hydrogen, fluorine or chlorine; ^R3 is ^{-CONHSOR3 R3} is 1
The compound is an alkyl group having 1 to 4 carbon atoms which may be substituted with one or more chlorine or one or more alkoxycarbonyl substituents. Examples of compounds of the invention are shown in Table 1.

【table】

[Table] As described below, the compound of the present invention can usually be produced from the corresponding compound in the general formula () in which R is a carboxyl group. The compound 5-(2-chloro-4-trifluoromethylphenoxy)-2-trifluoromethylbenzoic acid described in Example 18 as an intermediate for compound 37 of the present invention is considered to be a new compound. It will be done. Compounds of the invention can be made in a variety of ways. In one method shown in reaction formula A below,
A suitably substituted carboxyl-bearing diphenyl ether derivative () is converted to the corresponding carbonyl chloride by reaction with a chlorinating agent according to standard methods. The carbonyl chloride () thus obtained is then reacted with alkanesulfonamide R ³ SO ₂ NH ₂ in the presence of an acid acceptor to give the compound of the invention. Examples of acid acceptors are tertiary amines such as pyridine and triethylamine. Other acid acceptors can include alkali metal carbonates, such as anhydrous potassium carbonate. Alkali metal fluorides, especially cesium fluoride, may also be used. In Reaction Scheme A, the starting material () can have all of the substituents required for the final target compound (). Alternatively-
After forming CONHSO ₂ R ³ substituents on the molecule,
One or more substituents may also be introduced. For example, if substituent A is to be a nitro group in the final compound, the reaction of Scheme A is initiated using a compound in which substituent A is hydrogen, and the nitro group is used in the second reaction of Scheme A. can be introduced by a conventional nitration reaction in the final step after carrying out. Alternatively, the compounds may be prepared and one or more substituents may be converted to other substituents by conventional chemical methods. For example, a compound () in which A is an amino group can be produced by reduction of a compound () in which A is a nitro group. The boxyl group-substituted diphenyl ether derivative () can be produced by various methods. In one method, a suitably substituted phenol may be reacted in salt form with an ester (e.g., methyl ester) of 3-carboxy-4-nitrofluorobenzene, as described in Example 8 for compound 38 of Table 1. . Hydrolysis of the ester thus obtained (for example by treatment with a mixture of acetic acid and aqueous hydrobromic acid) gives the corresponding carboxylic acid (). In another method, the same reaction as above is carried out using the ester of 3-carboxy-4-nitrochlorobenzene instead of the ester of 3-carboxy-4-nitrobenzene, as shown in Example 6. It can be done. In yet another method, 3-hydroxybenzoic acid or 2-substituted-5-hydroxybenzene, in its di-salt form, is reacted with an appropriately substituted fluoro- or chlorobenzene, as described in Examples 17 and 5. can be done. An example of the production of the compound of general formula () is shown below. Intermediate 35 (Table 1, intermediate for producing compound 35) 3-Hydroxybenzoic acid (13.8 g) was anhydrous with anhydrous potassium carbonate (26 g) and 4-chloro-3-nitrobenzotrifluoride (22.5 g). The mixture was heated and stirred at 100°C for 7 hours in dimethylformamide (100ml). The reaction mixture was evaporated to a small volume under reduced pressure and then diluted with water. Upon warming, a dark solution was obtained. Acidification gave a white precipitate; this precipitate was recrystallized from a methanol-water mixture to give 3-(2-nitro-4-trifluoromethylphenoxy)benzoic acid (24 g). The compounds of this invention are useful both as pre-emergence herbicides and as post-emergence herbicides. Pre-emergence herbicides are commonly used to treat the soil to be planted with crops by application before or at the time of sowing, or after sowing and before the emergence of the crop. Post-emergence herbicides are applied after the crop emerges from the soil. The compounds of the present invention may be used as selective herbicides on a variety of crops including, for example, cotton, soybeans, peanuts, peas, wheat, sugar beets, and rice. The compounds of the invention may also be used as total herbcides. The compounds of the invention may be applied by any conventional method for applying herbicides. When applied as a pre-emergence herbicide, the compounds of the invention may be sprayed onto the soil surface, for example, before or at the time of sowing, or after sowing and before crop emergence. In some cases, for example when applying to soybean crops before germination, it may be advantageous to mix the compounds of the invention into the soil before sowing the crop. This method can be carried out by applying the compound of the present invention to the soil surface and tilling the soil to mix the two. Alternatively, the herbicide may be used by applying it to tilled soil to provide a lower zone of the soil surface. As is clear to those skilled in the art, the compound ()
The amount applied will vary depending on various factors, such as the particular compound selected and the type of plant that is not preferred. However, per hectare
The appropriate amount is 0.1-5.0Kg per hectare.
An amount of 0.25-1.0 Kg is preferred. The compounds of the invention are preferably administered in the form of a composition in which the active ingredient is mixed with a carrier consisting of a solid or liquid diluent. According to another aspect of the present invention, there is therefore provided a herbicidal composition comprising a compound of the general formula () as an active ingredient mixed with a solid or liquid diluent. Preferably, the composition also contains a surfactant. The solid herbicidal compositions of the invention may be in the form of powders for application or in the form of granules, for example. Suitable solid diluents include, for example, kaolin, bentonite, diatomaceous earth, dolomite, calcium carbonate, talc, powdered magnesia and Fuller's earth. Solid compositions may also include soluble powders or granules consisting of a mixture of a salt of a compound of the invention and a water-soluble carrier or a mixture of a compound of the invention and an alkali such as sodium or potassium carbonate; when mixed with water, this composition forms a solution of the salt of the compound of the invention. Solid compositions can also be dispersible powders or granules that contain, in addition to the active ingredient, wetting agents to facilitate the dispersion of the powder or granules in a liquid. Such powders or granules may contain fillers, suspending agents and the like. The liquid composition is an aqueous solution containing the active ingredient and preferably also one or more surfactants;
Includes dispersions and emulsions. Water or organic solvents may be used to prepare solutions, dispersions or emulsions of the active ingredient. The liquid compositions of the invention may also contain one or more corrosion inhibitors, such as lauryl isoquinolinium bromide. Surfactants can be of the cationic, anionic or nonionic type. Suitable cationic surfactants include, for example, quaternary ammonium compounds,
Examples include cetyltrimethylammonium bromide. Suitable anionic surfactants are, for example, soaps; salts of aliphatic monoesters of sulfuric acid, such as sodium lauryl sulfate; and salts of sulfonated aromatic compounds, such as dodecylbenzenesulfonate, lignosulfonic acid and butylnaphthalenesulfone. Includes sodium, calcium and ammonium salts of acids and mixtures of sodium diisopropylnaphthalene sulfonate and sodium triisopropylnaphthalene sulfonate. Suitable nonionic surfactants include:
Examples include condensation products of ethylene oxide and aliphatic alcohols such as oleyl alcohol and cetyl alcohol or alkylphenols such as octylphenol, nonylphenol and octylcresol. Other nonionic surfactants are partial esters derived from long chain fatty acids and anhydrous hexitol, such as sorbitol monolaurate; condensation products of the above partial esters with ethylene oxide; and lecithins. Compositions to be used in the form of aqueous solutions, dispersions or emulsions may usually be supplied in the form of concentrates containing a high proportion of active ingredient, which are diluted with water before use. These concentrates usually withstand long-term storage and, after storage, can be diluted with water to produce aqueous formulations that retain homogeneity for a sufficient period of time to be able to be applied with conventional spray equipment. It's something you get. In addition to the carrier and surfactant, the herbicidal composition of the present invention may contain various other ingredients to increase its usefulness. Herbicidal compositions may contain, for example, buffers to maintain the PH of the composition in the desired range; antifreeze agents such as urea or propylene glycol; adjuvants such as oils and humectants; and when the composition is diluted with hard water. may contain sequestering agents such as citric acid and ethylenediaminetetraacetic acid to prevent the formation of insoluble precipitates. Aqueous dispersions may contain antisettling and anticaking agents. Herbicidal compositions may contain dyes and pigments to impart a characteristic hue. Agents may be added to increase viscosity in order to reduce the formation of fine droplets during spraying and thereby reduce spray drift. Other additives useful for specific purposes are well known to those skilled in the art. Concentrates are usually 10-85% by weight, preferably 25-85% by weight.
Advantageously, it contains 60% by weight of active ingredient. Dilute preparations for immediate use may contain varying amounts of active ingredient depending on the purpose for which they are used; however, most commonly suitable diluent preparations contain from 0.01 to 10% by weight, preferably from 0.1 to 1% by weight. % active ingredient by weight. Examples of the present invention are shown below. In the examples, parts and percentages are by weight unless otherwise specified. Example 1 This example shows the production of compounds Nos. 12 to 16 in Table 1. A vigorously stirred solution of 2-nitro-5-(2-chloro-4-trifluoromethylphenoxy)N-methanesulfonylbenzamide (40.0 g) and acetone (1250 ml) was heated to 15°C.
Titanium trichloride (450 ml,
A 30 W/V% chloride solution was slowly added. The reaction mixture was stirred for a further 30 minutes at room temperature and then neutralized (PH5) by adding sodium hydroxide and excess sodium bicarbonate solution, and then extracted with dichloromethane. The extract was washed with water, dried and evaporated,
Corresponding 2-amino derivative (30.26 g, melting point 184~
185°). A mixture of the above 2-amino derivative (1.6 g), acetic anhydride (0.4 ml) and acetonitrile (15 ml) was heated under reflux for 2.5 hours, then evaporated under vacuum and the residue was recrystallized from methanol to give compound no. .12 (1.5 g, melting point 201°) was obtained. Compounds Nos. 13, 14 and 15 were prepared in a manner similar to that described above using the appropriate anhydride and chloroformate. Compound No. 16 was produced by reacting the above amine with dimethyl-ammonium N,N-dimethylthiocarbamate in N,N-dimethylformamide. 2-nitro-5-(2-
chloro-4-trifluoromethylphenoxy)N
-Methanesulfonylbenzamide was prepared as follows: 5-(2-chloro-4-trifluoromethylphenoxy)-2-nitrobenzoic acid (1.85 g) was refluxed in excess thionyl chloride (20 ml) for 90 minutes. heated under. After removing excess thionyl chloride under vacuum, the residue was dissolved in anhydrous pyridine (20ml). After adding methanesulfonamide (0.45g), the mixture was stirred at room temperature overnight. After removing the pyridine under vacuum, the residual oil was mixed with 2-molar hydrochloric acid and extracted with ether (2 x 100 ml), the ether extract was washed with water (100 ml), dried and evaporated under vacuum. Ta. The residual solid was recrystallized from isopropanol to give 5-(2-chloro-4-trifluoromethylphenoxy)-2-nitro-methanesulfonylbenzamide (melting point 201°). Example 2 This example describes the production of compound No. 17 in Table 1. 2-Amino-5-(2-chloro-4-trifluoromethylphenoxy)N-methanesulfonylbenzamide (3.0 g, prepared in Example 1) was mixed with sodium methoxide (from 190 mg of sodium) and methanol (60 ml). ) was added to a solution consisting of After the mixture was warmed until complete dissolution, it was cooled to 0° C. and treated with trifluoronitrosomethane until the starting material was consumed. After diluting with water,
Acidified with 2N hydrochloric acid and extracted with ether.
After washing the extract with water and brine, it is evaporated and the residue is dissolved in toluene/petroleum ether (boiling point 80~
100°) to obtain Compound No. 17 (3.3 g). Example 3 This example shows the production of compound No. 18 in Table 1. A vigorously stirred solution of 2-nitro-5-(2-chloro-4-trifluoromethylphenoxy)N-methanesulfonylbenzamide (4.4 g) and 0.5N sodium hydroxide solution (20 ml) was mixed with hypochlorite. It was treated sequentially with sodium phosphate (4.4 g) and 10% palladium on carbon (440 mg). 1
After an hour, the mixture was diluted with water and extracted with ethyl acetate. After washing the extract with water and brine,
Dry and evaporate. The residue is converted into petroleum ether (boiling point 40
~60°) and recrystallized from acetonitrile to obtain Compound No. 18. Example 4 This example describes the production of compound No. 19 in Table 1. A solution consisting of 2-amino-5-(2-chloro-4-trifluoromethylphenoxy)N-methanesulfonylbenzamide (2.03 g) and 1N sodium hydroxide was mixed with sodium nitrite (400 mg) and water (5 ml). ). The resulting solution was diluted with concentrated hydrochloric acid (7.5 ml) and water (2.5 ml).
It was added dropwise to the stirred solution which had been cooled to 0.degree.
The diazonium chloride was filtered, washed with ether and heated on a steam bath for 30 minutes in water (20ml). The mixture was cooled and filtered. The solid is dried and recrystallized from toluene to form the compound, compound
No. 19 (1.06 g) was obtained. Example 5 This example follows the preparation of compound No. 20 in Table 1. Sodium hydride (2.3 g, 50% mineral oil dispersion,
A mixture of 4-hydroxy-2-methylbenzoic acid (3.4 g) and anhydrous N,N-dimethylformamide (30 ml) was stirred for 30 minutes and then 3-chloro- 4
-Fluorobenzotrifluoride (4.5g) was added. After heating the mixture at 130°C for 5 hours,
It was acidified with 2N hydrochloric acid and extracted with ethyl acetate.
The extracts were washed with water and brine, then dried and evaporated. Convert the residue into petroleum ether (boiling point 80-100°)
Recrystallization from 2-methyl-5-(2-chloro-4-trifluoromethylphenoxy)benzoic acid (2.06 g, melting point 113°) was obtained. This compound (1.34
A suspension of g) and thionyl chloride (5ml) was heated under reflux for 1 hour and excess reactant was removed under vacuum. The residue was dissolved in acetonitrile and evaporated again to obtain crude acid chloride. Methanesulfonamide (0.41g), potassium carbonate (1.15g) and methyl ethyl ketone (10ml)
The mixture was heated under reflux for 30 minutes and a solution of the acid chloride and methyl ethyl ketone (10 ml) was added dropwise over 2 hours. After heating for an additional hour, the mixture was cooled, diluted with water, acidified with 2N hydrochloric acid, and extracted with ethyl acetate. The extract was washed with water and brine, then dried, evaporated and the residue was recrystallized from toluene/petroleum ether to give compound No. 20 (0.56 g). Example 6 This example describes the production of compound No. 22 in Table 1. (a) 2,4,5-trichlorophenol (20g)
Sodium hydride (5.28 g, 50% dispersion in mineral oil) was added in small portions to a mixture consisting of
Heated to 120°C. A solution of ethyl 5-chloro-2-nitrobenzoate (16.5g) and anhydrous dimethylacetamide (60ml) was added and the mixture was heated at 160°C for 10 hours. remove the solvent,
After washing the residue with water, it was extracted with ether. After evaporating the ether solution and solidifying the residual oil, it was recrystallized from ethanol to give 5-(2,
Ethyl 4,5-trichlorophenoxy)-2-nitrobenzoate (melting point 99-102°, 10.9 g) was obtained. (b) The product of (a) was heated at 70°C for 8 hours with a solution of sodium hydroxide (1.02g) and water (30ml) in isopropanol (50ml). After removing the isopropanol, the residue was acidified with dilute hydrochloric acid and extracted with methylene dichloride. Evaporation of methylene dichloride gave an oil which was crystallized and then recrystallized from toluene to give a 2-
Nitro-5-(2,4,5-trichlorophenoxy)benzoic acid (5.5 g), melting point 157-161°C, was obtained. (c) The product of (b) (4 g) was added to thionyl chloride (20 ml).
Heating under reflux for 4 hours gave an oil (4 g) which solidified on standing. (d) A solution consisting of the acid chloride (2 g) obtained in (c) and anhydrous methyl ethyl ketone (20 ml) was dissolved in methanesulfonamide (0.75 g) in anhydrous methyl ethyl ketone (10 ml) containing anhydrous potassium carbonate (1.1 g). The solution was added dropwise over a period of 2 hours and maintained at reflux temperature. 3 more of the mixture
After heating for an hour, it was left overnight. The mixture was stirred with dilute hydrochloric acid (100ml) and then extracted with ethyl acetate (150ml). Ethyl acetate was evaporated to give an extract which was triturated with dilute hydrochloric acid to solidify. This solid was recrystallized from toluene to obtain Compound No. 22 (melting point 170-171°C). Example 7 This example describes the production of compound No. 23 in Table 1. (a) 2-nitro-5-(2-chloro-4-trifluoromethylphenoxy)benzoic acid (10 g),
A mixture of 1,2-dichloroethane (50ml) and concentrated sulfuric acid (50ml) was cooled to -5°C and potassium nitrite (2.79g) was slowly added while maintaining the temperature below 0°C. Add more of the mixture
After stirring for 1.5 hours, the mixture was warmed to room temperature and further stirred for 1 hour. After pouring the reaction mixture onto ice, the resulting mixture was extracted with chloroform. Chloroform extraction gave an oil which was shaken with ether and sodium bicarbonate solution. The sodium bicarbonate solution was washed with ether and acidified to give an oil. This oil was extracted with ether to give a pale yellow oil (8.1 g). The oil was dissolved in ether/hexanes and cooled to crystallize the product. The resulting carboxylic acid was treated with thionyl chloride to convert the acid chloride according to a method similar to Example 6(c). (b) The product of (a) (3 g) and anhydrous pyridine (15 ml)
After cooling the mixture to 0°C, methanesulfonamide was added. The mixture was left at room temperature for 24 hours, then poured onto ice and acidified to give a brown solid. After dissolving the solid in ether, the solution was filtered and added to hexane with stirring to give a white solid (0.7 g). Recrystallized from chloroform/hexane to a melting point of 206°C (120°C).
Compound No. 23 (0.53 g) (softens at °C and solidifies again)
I got it. This compound is 5-(2-chloro-4-trifluoromethylphenoxy)-2-nitro-N-
It was also prepared by nitration of methanesulfonylbenzamide according to method (a) above. Example 8 This example describes the production of compound No. 38 in Table 1. Methyl 5-fluoro-2-nitrobenzoate and 4
-Sodium salt of chloro-3-methylphenol (prepared from sodium hydride and the above phenol)
were reacted in dimethylformamide at 100°C for 2.5 hours, and the obtained methyl 5-(4-chloro-3-methylphenoxy)-2-nitrobenzoate (melting point 85-87°C) was isolated by a conventional method. . This ester was then hydrolyzed to the corresponding carboxylic acid. The carboxylic acid was converted to the corresponding carboxylic acid chloride and then reacted with methanesulfonamide in the presence of pyridine as the acid acceptor to yield Compound No. 38. Example 9 This example illustrates the preparation of compound 26 in Table 1. Compound No. 19 tetrafluoroborate (1.43g),
Tetrabutylammonium thiocyanate (1.1
To a stirred solution of g) and acetonitrile (10ml) was added copper chromite (0.15g). After 1 hour, the mixture was poured into water and extracted with ethyl acetate. The extracts were washed with water, dried and evaporated. The oil thus obtained was chromatographed on silica gel in acetonitrile to give an oil (1.0 g). Compound No. 26 with a melting point of 135℃ (decomposition) when triturated with isopropanol
(0.42g) was obtained. Example 10 This example describes the production of compound No. 27 in Table 1. Sodium azide (1.6g), compound No. 19 tetrafluoroborate (2.0g) and acetone (80ml)
was added to the solution little by little. After 30 minutes, the acetone was removed under reduced pressure. The residue was shaken with ethyl acetate and water and the ethyl acetate extract was washed with water and brine, dried and evaporated. Triturate the residue with ether/petroleum ether (boiling point 40-60°),
The obtained solid was recrystallized from carbon tetrachloride to determine the melting point.
Compound No. 27 (1.02 g) was obtained at 119°C (decomposed). Example 11 This example describes the production of compound No. 29 in Table 1. Tetrafluoroborate of compound No. 19 (4.3g)
was added in small portions to the stirred trimethylphosphite while maintaining the temperature at 25-30°C by external cooling. After an additional hour, the mixture was diluted with water and extracted with ethyl acetate. The extracts were washed with water and then brine, then dried and evaporated. The residue was triturated with ether to obtain Compound No. 29 (0.8 g) with a melting point of 159° (decomposed). Example 12 This example shows the production of N-(methoxycarbonylmethanesulfonyl)-5-(2-chloro-4-trifluoromethylphenoxy)-2-nitrobenzamide (Compound No. 7 in Table 1). . 5-(2-chloro-4-trifluoromethylphenoxy)-2-nitrobenzoic acid (2.36 g) was heated in thionyl chloride (20 ml) under reflux for 90 minutes. The mixture was cooled and excess thionyl chloride was removed under reduced pressure. Toluene was added twice and removed under reduced pressure. The residue was diluted with butyl acetate (35ml) and heated under reflux with methoxycarbonylmethanesulfonamide (1g) and cesium fluoride (3g) for 20 hours. The mixture was poured into water and then extracted with ethyl acetate. Wash the extract with water,
Drying and evaporation gave an oil. After diluting the oil with ether, the ether solution was treated with charcoal and diluted with light petroleum. The separated yellow solid was purified by thin layer chromatography using silica gel as the solid phase and acetonitrile as the eluent. The oil thus obtained is crystallized by addition of ether/light petroleum,
The target compound (0.31 g) with a melting point of 158-160°C was obtained. Example 13 This example describes the production of compound No. 6 in Table 1. 5-(2-chloro-4-trifluoromethylphenoxy)-2-nitrobenzoic acid (3.62 g) was heated under reflux in thionyl chloride (30 ml) for 2 hours. Excess thionyl chloride was removed and toluene was added twice to the residue and evaporated. The residual oil was diluted with butyl acetate and heated under reflux with 3-chloropropanesulfonamide (1.58 g) and cesium fluoride (3 g) for 9 hours. After cooling the reaction mixture, it was diluted with water and extracted with ethyl acetate. After acidifying the aqueous solution with dilute hydrochloric acid,
Extracted again with ethyl acetate. The extracts were combined, dried and evaporated to give an oil. This was dissolved in carbon tetrachloride, decolorized with charcoal, and cooled. Petroleum ether (boiling point 40-60°) was added slowly to give an oily solid. Add this to chloroform.
Dissolved in acetone-acetic acid (90:10:5) mixture and passed the solution through a silica gel column. The solution was evaporated and the residue was purified by thin layer chromatography on silica gel plates using a chloroform-acetone-acetic acid (90:10:5) mixture as eluent. The main component, ethanol, was extracted from a silica gel plate. The ethanol was evaporated and the residue was stirred with dilute hydrochloric acid and ethyl acetate. The ethyl acetate extract was washed with water, dried and evaporated. The residue was recrystallized from an ether-petroleum (boiling point 30-40°) mixture to obtain the desired compound as a solid (0.9 g) with a melting point of 116-119°C. Example 14 This example shows N-benzenesulfonyl-5-(2
-Chloro-4-trifluoromethylphenoxy)
-2-Nitrobenzamide (Compound No. 1 in Table
) production. 5-(2-chloro-4-trifluoromethylphenoxy)-2-nitrobenzoic acid (2g) was heated under reflux in thionyl chloride (15ml) for 90 minutes.
Excess thionyl chloride was removed under reduced pressure and the residue was diluted with toluene. Toluene was removed under reduced pressure;
The residual oil was dissolved in butyl acetate. Benzene sulfonamide (1.3g) and cesium fluoride (4.0g)
After addition, the mixture was heated and stirred under reflux for 90 minutes. After cooling the reaction mixture, it was diluted with water, acidified (HCl) and extracted with ethyl acetate. The extract was washed with water, dried and evaporated to give an oil. This was triturated with carbon tetrachloride and petroleum to obtain a solid. This solid was recrystallized from a carbon tetrachloride-ether-petroleum mixture to obtain the desired compound (1.11 g) with a melting point of 123-125°C. Example 15 This example shows N-methanesulfonyl-5-(2-
The production of methanesulfinyl-4-trifluoromethylphenoxy)-2-nitrobenzamide (Compound No. 28 in Table 1) is shown. (a) Preparation of methyl 5-(2-methanesulfinyl-4-trifluoromethylphenoxy)-2-nitrobenzoate 5-(2-amino-4-trifluoromethyl in concentrated hydrochloric acid (35 ml) Methyl phenoxy)-2-nitrobenzoate (8 g) was cooled to 0-5°C and a solution of sodium nitrite (1.86 g) was added dropwise while maintaining the temperature at 0-5°C and stirring vigorously. The mixture was stirred for 30 minutes and then poured into a solution of sodium fluoroborate (5.44 g) and water (6 ml). The precipitated diazonium fluoroborate salt (8.74 g) was washed with aqueous sodium fluoroborate solution, cold ethanol, and ether. A solution consisting of the thus obtained diazonium salt (8.74 g) and anhydrous dimethyl sulfoxide (20 ml) was
It was added dropwise to a stirred solution of potassium iodide (6.38 g) and anhydrous dimethyl sulfoxide (30 ml) and the mixture was stirred at room temperature for 1 hour. The mixture was poured into water and extracted with ether. After the ether extract was washed with water, dried and treated with charcoal,
Evaporation gave an oil. After extracting this several times with petroleum (boiling point 60-80°), it is evaporated to give 5-(2
-Iodo-4-trifluoromethylphenoxy)
Methyl -2-nitrobenzoate was obtained. The extraction residue was dissolved in ether and passed through a preparative chromatography plate coated with silica gel. The plate was eluted with chloroform containing 2% ethanol. Two products were obtained;
The first was the iodo compound described above (6 g). A second product (0.95 g) was identified as the desired methanesulfinyl compound. (b) Production of compound Methanesulfinyl compound obtained in (a) (0.95g)
5-(2-
Hydrolyzed to methanesulfinyl-4-trifluoromethylphenoxy)-2-nitrobenzoic acid. The substituted benzoic acid thus obtained is converted to its acid chloride and treated with methanesulfonamide and cesium fluoride in refluxing butyl acetate according to the method described in Example 16(d) to give a melting point of 158-160°C.
Compound 16 was obtained. Example 16 This example shows N-methanesulfonyl-5-(2,
The production of 3,5,6-tetrafluoro-4-trifluoromethylphenoxy)-2-nitrobenzamide (compound 30 in Table 1) will be described. (a) 5-(2,3,5,6-tetrafluoro-4
-Production of ethyl benzoate (trifluoromethylphenoxy) Pentafluorobenzotrifluoride (11.8
g) in anhydrous dimethyl sulfoxide (75 ml).
- Ethyl hydroxybenzoate (8.3 g) and anhydrous potassium carbonate (7.0 g) were stirred for 2 hours and then left overnight. The mixture was poured into water (600ml) and extracted with ether (2x250ml). The extract was washed with water (400ml), dried and evaporated to a colorless liquid (18.4ml) identified as the desired ester.
g) was obtained. (b) 5-(2,3,5,6-tetrafluoro-4
-Production of ethyl (trifluoromethylphenoxy)-2-nitrobenzoate The ester obtained in (a) (15.28 g) and 1,2-dichloroethane (100 ml) were cooled to 0°C, and then the temperature was lowered to 5°C or lower. Concentrated sulfuric acid (100 ml) was added little by little while stirring. After the mixture was cooled to 0°C, potassium nitrate (4.44g) was added portionwise over 75 minutes while keeping the temperature below 5°C. The mixture was stirred for a further 1 hour at 5°C and then poured into ice (500ml). The mixture was extracted with ether (3x200ml). The ether extract was washed with water (5 x 500ml) until the wash water was neutral. The extracts were dried (MgSO ₄ ) and evaporated to give an oil that solidified on standing. This solid is petroleum (boiling point 30~
Recrystallization from 40°) gave a colorless solid (13.4 g) identified as the desired nitro compound. Samples recrystallized from petroleum (boiling point 60-80°) showed melting points of 77-78°C. (c) Production of 2-nitro-5-(2,3,5,6-tetrafluoro-4-trifluoromethylphenoxy)benzoic acid The product of (b) (9.0 g) was mixed with acetic acid (180 ml). with a mixture of and a 40% aqueous solution of hydrobromic acid (90 ml).
The mixture was heated and stirred under reflux for 6.25 hours. After the mixture was cooled, it was allowed to stand overnight and then evaporated under reduced pressure.
Toluene was added twice to the residue and evaporated under reduced pressure. The residual solid was recrystallized from a mixture of toluene (80 ml) and petroleum (bp 80-100°, 120 ml) to give the desired acid (6.5 g), melting point 138-139.5°C. (d) Preparation of compound 30 The product of (c) (3.5 g) was mixed with thionyl chloride (60 ml).
The mixture was heated under reflux for 3 hours. After removing excess thionyl chloride under reduced pressure, the residue was treated with anhydrous cesium fluoride (3.3 g) and methanesulfonamide (1.67 g).
g) in anhydrous butyl acetate (50 ml) under reflux,
The mixture was heated and stirred for 2.5 hours. After cooling the reaction solution,
Diluted with ethyl acetate (150ml) and diluted hydrochloric acid.
The organic phase was separated, washed with water (30x200ml) and dried. The solvent was removed under reduced pressure to give a colorless solid (3.5
g) was obtained, which was then washed with petroleum (boiling point 30-40°) and recrystallized from isopropanol to obtain compound No. 30 with a melting point of 177-177.5°C. Example 17 This example shows N-methanesulfonyl 5-(2-chloro-5-trifluoromethylphenoxy)-2
-Nitrobenzamide (Compound No. 32 in the table) and N-methanesulfonyl-3-(2-chloro-
The production of 5-trifluoromethylphenoxy)benzamide (Compound No. 31) will be shown. (a) Preparation of 4-chloro-3-fluorobenzotrifluoride 3-amino-4-chlorobenzotrifluoride was diazotized by standard methods and the diazonium salt was isolated as the fluoroborate. This compound was decomposed by heating with the flame of a Bunsen burner.
4-chloro-3-fluorobenzotrifluoride was distilled and then redistilled at atmospheric pressure (boiling point
(128°C) (b) Preparation of 3-(2-chloro-trifluoromethylphenoxy)benzoic acid 3-hydrobenzoic acid (3.45g) was added to a solution of potassium hydroxide (2.8g) in methanol.
The solution was then distilled under reduced pressure to obtain a white solid. This solid was dissolved in anhydrous dimethyl sulfoxide (25
ml). The resulting solution was mixed with anhydrous potassium carbonate (1.25 g) and 4-chloro-3-fluorobenzotrifluoride (5 g) at 170°C.
The mixture was heated and stirred for 12 hours. After cooling the reaction mixture was poured into water (500ml). The mixture was extracted with ether and acidified (HCl). The formed precipitate is recrystallized from petroleum (boiling point 60-80°),
The desired acid (4.5 g) was obtained with a melting point of 142-143°C. (c) Production of 5-(2-chloro-5-trifluoromethylphenoxy)-2-nitrobenzoic acid The acid obtained in (b) (2.0 g) was mixed with concentrated sulfuric acid (15 ml) kept at 0°C. ) and 1,2-dichloroethane (10ml)
was added to the mixture. Then, while maintaining the temperature at 0° and stirring, add sodium nitrate (1.2 g).
was added. The mixture was stirred for a further 1 hour at 0°C and then for a further 3 hours at room temperature. The mixture was then poured onto ice and extracted with ethyl acetate. The extract was washed with water, dried and evaporated to give a dark gum. This was extracted several times with boiling cyclohexane. The residue is cooled and crystallized to a melting point of 147-148
C. The desired nitro-acid was obtained. (d) Production of Compound No. 32 The nitro acid compound (0.8 g) obtained in (c) was heated with thionyl chloride (25 ml) under reflux for 3 hours.
After removing excess thionyl chloride under reduced pressure, the residual oil was dissolved in pyridine (20ml). After adding methanesulfonamide (0.5 g), the mixture was heated and stirred under reflux for 3 hours. After removing the pyridine under reduced pressure, the residue was stirred with ethyl acetate and dilute hydrochloric acid. The ethyl acetate layer was washed with water, dried and evaporated to give a brown gum. Melting point 204, identified as compound No. 32 by trituration with cold ether
A beige solid was obtained at ~205°C. (e) Preparation of Compound No. 31 The acid compound (0.8 g) obtained in (b) was mixed with thionyl chloride and then with methanesulfonamide and pyridine according to the same method as in step (d) for the preparation of Compound No. 32. Processed with. The product is ether-petroleum (boiling point
Recrystallized from the mixture (40~60℃), melting point 132~
Compound 31 was obtained at 133°C. Example 18 This example shows N-methanesulfonyl-5-(2-
Chloro-4-trifluoromethylphenoxy)-
The production of 2-trifluoromethylbenzamide (Compound No. 37 in Table 1) is shown below. Finely powdered 2-amino-5-(2-chloro-
4-Trifluoromethylphenoxy)benzoic acid (16.5g) was suspended in fluoroboric acid (120ml, 40%), then ethanol (100ml) was added and cooled to 0°C. A solution of sodium nitrite (4.5 g) and water (20 ml) was added dropwise to the stirring reaction. After a further 15 minutes at 0° C., the crystalline precipitate was separated and washed with ether to give diazonium fluoroborate (12.32 g). Sodium iodide (4.5 g) was added to a stirred solution of this diazonium salt (11.7 g) and acetonitrile (100 ml). 20 for another 15 minutes
After stirring at °C, boiling stopped. The solvent was removed under vacuum and the residue was partitioned between dichloromethane and water. The extracts were washed with water, dried and evaporated.
The crude product was flash chromatographed on silica gel in ether with 2-iodo-5-
10.2 g of a mixture of methyl (2-chloro-4-trifluoromethylphenoxy)benzoate and its 2-H derivative (80:20, gas chromatography) was obtained. This product was mixed with trifluoromethyl iodide (5 ml),
Acetonitrile (15ml), anhydrous pyridine (5ml)
and the freshly prepared copper powder (2.5 g) in a sealed Teflon-lined pressure vessel at 150° C. for 18 hours. The crude reaction mixture was filtered through Supercel (diatomaceous earth), evaporated under vacuum, dissolved in ether, washed with 2N hydrochloric acid and water, dried and dissolved in ethyl acetate/petroleum (boiling point 60-80).
(1:3) on silica gel. Pure 2-trifluoromethyl-5-
A product containing methyl (2-chloro-4-trifluoromethylphenoxy)benzoate (600 mg) and a 2H-derivative was obtained. The latter was chromatographed again to obtain an additional 250 mg of pure product. The 2-CF ₃ ester (1.62 g) obtained above was mixed with potassium hydroxide (230 mg), water (3 ml) and methanol (40 ml) and stirred at 60° C. for 6 hours. The mixture was diluted with water, extracted with ether to remove unconverted ester, acidified with 2N hydrochloric acid, and extracted with ethyl acetate. The latter extract was washed with water and brine, dried and evaporated, and the residue was then chromatographed on silica gel in dichloromethane to give an oil which gradually crystallized on standing to give 5-( A white solid with a melting point of 81°C, identified as 2-chloro-4-trifluoromethylphenoxy-2-trifluoromethylbenzoic acid.
1.08g was obtained. This material (0.69 g) was converted to the acid chloride according to the method of Example 6 (c) and (d) and treated with methanesulfonamide in the presence of anhydrous potassium carbonate in methyl ethyl ketone. , Compound No. 37 was obtained. Example 19 This example demonstrates the herbicidal activity of the compounds in Table 1.
The herbicidal test was conducted using the method described below. An appropriate amount of the test compound was added to 5 ml of an emulsion prepared by diluting 160 ml of a solution containing 21.1 g/Span 80 and 78.2 g/Tween 20 in methylcyclohexanone to 500 ml with water. A formulation of each test compound was prepared by mixing. Span 80 is a trademark for a surfactant consisting of sorbitan monolaurate. Tween 20 is a trademark for a surfactant consisting of a condensate of 20 moles of ethylene oxide and sorbitan monolaurate. The mixture of test compound and emulsion was shaken with glass beads and then diluted to 40 ml with water. The spray composition thus obtained was sprayed on the seedlings of the plants shown in Table 1 at a rate of 1000 per hectare. (Post-emergence test) The extent of plant damage was evaluated after 14 days while spraying using a scale of 0 to 5 compared to untreated control plants. In the above grades, 0 represents 0-20% damage and 5 represents complete death. The symbol (-) in the table indicates that the test was not conducted. Tests were also conducted to determine pre-emergence herbicidal activity. After sowing the seeds of the test plants on the soil surface in fiber trays, the test formulation was sprayed at a rate of 1000 seeds per hectare. Three weeks after spraying the formulation, the seedlings in the fiber trays were compared with the seedlings in the untreated control trays, and the degree of damage was rated on a scale of 0 to 5. The test results are shown in Table 1.

【table】

【table】

[Table] The table shows the results of a herbicidal test on 5-(2-chloro-4-trifluoromethylphenoxy)-2-trifluoromethylbenzoic acid, which is useful as an intermediate for compound No. 37 in the table. The test method is the same as in Table 1. The above compound is designated as compound A in the table. Other intermediates are indicated by the following numbers. Intermediate 67 Compound B 〃 69 〃 C 〃 70 〃 D 〃 71 〃 E

【table】

Claims (1)

[Claims] 1 General formula (): [In the formula, A is hydrogen, _NO2 , N=N- _CF3 ,
NH ₂ , NHOH, -N ₂ ⁺ , NHCOR ¹ (R ¹ represents an alkyl group, CF ₃ or a mono- or dialkylamino group), alkyl group, NHSO ₂ R ² (R ² represents an alkyl group), -SCN , N ₃ , CF ₃ or [Formula]; B represents hydrogen, fluorine, chlorine, an alkylsulfinyl group, or NO ₂ ; C represents hydrogen, halogen, or an alkyl group; D represents hydrogen, halogen, CF ₃ or a nitro group; E represents hydrogen, halogen or _CF3 ;
F represents hydrogen, fluorine or chlorine; R is a group -
CONHSO ₂ R ³ (R ³ is a phenyl or indanyl group optionally substituted with one or more halogen atoms, an alkyl group or a nitro group; or one or more chlorine or one or more (represents an alkyl group having 1 to 4 carbon atoms which may be substituted with an alkoxycarboninyl substituent). 2 A is hydrogen or a nitro group; B is a nitro group; C is hydrogen; D is fluorine, chlorine, bromine, iodine or _CF3 ; E is hydrogen; F
is hydrogen, fluorine or chlorine; R is
The compound according to claim 1, which is a CONHSO ₂ R ³ group (R ³ is a methyl group or an ethyl group). 3 A is a methyl group or a trifluoromethyl group; B is fluorine or chlorine; C is hydrogen; D is fluorine, chlorine, bromine, iodine or _CF3 ; E is hydrogen; F is hydrogen, fluorine or chlorine; R ³ is -CONHSOR ³ group (R ³ has 1 to 4 carbon atoms optionally substituted with one or more chlorine or one or more alkoxycarbonyl substituents); 2. The compound according to claim 1, which represents an alkyl group of 4 Group F is a fluorine atom; C and E are hydrogen; B and D are the aforementioned substituents other than hydrogen; R is -CONHSO ₂ R ³ (R ³ is one or more chlorine or one 1 to 4 carbon atoms, which may be substituted with one or more alkoxycarbonyl substituents
represents an alkyl group); and A is the above-mentioned substituent other than hydrogen,
A compound according to any of paragraph 3. 5 B, C, E and F are all fluorine atoms; D is CF ₃ and A is a nitro group or CF ₃ ; R is -CONHSO ₂ R ³ group (R ³ is one or more 2. A compound according to claim 1, which is an alkyl group having 1 to 4 carbon atoms and optionally substituted by chlorine or one or more alkoxycarbonyl substituents. 6 General formula (): [In the formula, A is hydrogen, _NO2 , N=N- _CF3 ,
NH ₂ , NHOH, -N ₂ ⁺ , NHCOR ¹ (R ¹ represents an alkyl group, CF ₃ or a mono- or dialkylamino group), alkyl group, NHSO ₂ R ² (R ² represents an alkyl group), -SCN , N ₃ , CF ₃ or [Formula]; B represents hydrogen, fluorine, chlorine, an alkylsulfinyl group, or NO ₂ ; C represents hydrogen, halogen, or an alkyl group; D represents hydrogen, halogen, CF ₃ or a nitro group; E represents hydrogen, halogen or _CF3 ;
F represents hydrogen, fluorine or chlorine; R is a group -
CONHSO ₂ R ³ (R ³ is a phenyl or indanyl group optionally substituted with one or more halogen atoms, an alkyl group or a nitro group; or one or more chlorine or one or more optionally substituted with an alkoxycarbonyl substituent,
A herbicidal composition containing as an active ingredient at least one diphenyl ether compound represented by the following formula (representing an alkyl group having 1 to 4 carbon atoms).