JPS6258359B2 - - Google Patents

Description

[Detailed description of the invention]

The present invention is based on (1) general formula () (In the formula, R represents a lower alkyl group having 1 to 3 carbon atoms.) A substituted phenylhydantoin derivative represented by (2)
General formula () (In the formula, R is as described above.) A substituted phenyl isocyanate derivative represented by the formula (R) is reacted with an alkali metal salt of pipecolic acid to form a compound of the general formula () (In the formula, R is as described above, and M represents an alkali metal atom.) A urea derivative represented by the formula is obtained, and then this is mixed with hydrochloric acid,
A method for producing a substituted phenylhydatoin derivative, which is characterized by treatment with a suitable mineral acid such as sulfuric acid to cause ring closure, and (3) a herbicide containing a phenylhydantoin derivative represented by the general formula () as an active ingredient. It is. The compound of the present invention is a new compound that can be used for pre- or post-emergence treatment of upland weeds and paddy field weeds.
It is characterized by extremely high herbicidal activity at low doses. The compound of the present invention is included in the general formula described in JP-A-51-95134 and US Pat. 2- with a similar structure as described or included in the general formula
(4-chlorophenyl)-5,6,7,8-tetrahydroimidazo-[1,5a]-pyridine-1,3
(2H, 8aH)-dione (comparative control compound (a) described below)
or 2-(4-chloro-2-fluorophenyl)-
5,6,7,8-tetrahydroimidazo-[1,
5a]-Pyridine-1,3(2H,8aH)-dione (Comparative Compound (b) described later), it is clear from the Examples described below that the compound of the present invention exhibits superior herbicidal activity at lower doses. It is being done. Such properties are one of the outstanding features of the compounds of the present invention. Furthermore, crop selectivity is observed in the compounds of the present invention. For example, as shown in the examples below,
Selectivity was observed for corn and wheat when treated with field-like foliage, and for soybean and cotton when treated with field-like soil.
The compound of the present invention can be used as a selective herbicide for corn, wheat, soybeans, or cotton by utilizing these properties. In addition, the compound of the present invention has the excellent characteristics that when used in paddy fields, it causes little phytotoxicity to rice and has high activity against perennial weeds that are difficult to control with conventional chemicals, such as weeds, pine grass, and bulrushes. ing. Next, the method for producing substituted phenylhydantoin derivatives according to the present invention will be explained in detail. The phenylhydantoin derivative represented by the general formula () can be produced, for example, according to the following reaction formula. (In the formula, R and M are as described above.) The substituted phenyl isocyanate derivative represented by the general formula () is dissolved as it is or in an inert solvent such as benzene, toluene, or chlorobenzene, and pipecolic acid The derivative is added to an aqueous solution of an alkali metal salt such as the sodium salt or potassium salt of pipecolic acid, or the derivative is added to an aqueous solution of a base such as sodium hydroxide or potassium hydroxide of pipecolic acid, heated if necessary at room temperature, and reacted. ()
Obtain the salt shown. This compound can be isolated if necessary, but instead of being isolated, it can be extracted with hydrochloric acid while in aqueous solution.
The ring is closed with a suitable mineral acid such as sulfuric acid to form the general formula ()
The compound of the present invention represented by can be obtained. The substituted phenyl isocyanate used as a raw material is synthesized from 2-chloro-4-fluorophenol, which is a known compound. Specifically, 2-chloro-4-fluorophenol was converted into an alkyl carbonate ester, then selectively nitrated, and the carbonate ester was hydrolyzed.
- After alkylating chloro-4-fluoro-5-nitrophenol by an appropriate method, the aniline obtained by reduction is obtained by heating if necessary in an inert solvent such as toluene together with phosgene. Can be done. In order to show the method for producing the compound of the present invention in more detail, Examples will be given and explained below. Example 1 2-(4-chloro-2-fluoro-5-isopropoxyphenyl)-5,6,7,8-tetrahydroimidazo-[1,5a]-pyridine-1,3
Synthesis of (2H,8aH)-dione (compound (3)) Dissolve 2.3 g of 4-chloro-2-fluoro-5-isopropoxyphenyl isocyanate in 10 ml of chlorobenzene, and dissolve 2.3 g of 4-chloro-2-fluoro-5-isopropoxyphenyl isocyanate in 2% solution containing 1.3 g of pipecolic acid.
The mixture was added to 25 ml of an aqueous sodium hydroxide solution, stirred at room temperature for 3 hours, and then left overnight. After the formed crystals were separated and washed with ether, 20 ml of water was added and the aqueous solution was adjusted to pH 2 or less with hydrochloric acid, followed by refluxing for 3 hours. After cooling, the mixture was extracted with ether, dried and concentrated, and the residue was purified by silica gel column chromatography to obtain 0.6 g of a waxy compound. NMR.δCDCl ₃ 1.4 (6H, d, J=6Hz), 4.2
~4.6 (1H, m), 6.8 (1H, d, J=6
Hz), 7.2 (1H, d, J = 10Hz) The following two compounds were synthesized in a similar manner. 2-(4-chloro-2-fluoro-5-methoxyphenyl)-5,6,7,8-tetrahydroimidazo-[1,5a]-pyridine-1,3(2H,
8aH)-dione (compound (1)) Waxy compound mp162-163℃ NMR.δCDCl ₃ 3.84 (3H, s), 6.8 (1H,
d, J = 6 Hz), 7.2 (1H, d, J = 10 Hz) 2-(4-chloro-2-fluoro-5-ethoxyphenyl)-5,6,7,8-tetrahydroimidazo-[1,5a ]-pyridine-1,3(2H,
8aH)-dione (compound (2)) Waxy compound NMR.δCDCl ₃ 1.46 (3H, t, J=6Hz),
4.04 (2H, q, J = 6Hz), 6.8 (1H, d,
J = 6 Hz), 7.2 (1H, d, J = 6 Hz) When actually applying the compound of the present invention obtained as described above, the raw material of the compound of the present invention () may be sprayed as it is. Generally, powders, granules,
Spread in formulations such as wettable powders and emulsions. The active ingredient content in the preparation is usually 0.1 to 80
% range, but depending on the purpose, the formulation can be 0.1% or less or 80% or more. In preparing these pharmaceutical products, solid carriers such as mineral powders (kaolin, bentonite, clay, montmorillonite, talc, diatomaceous earth, mica, vermiculite, gypsum,
calcium carbonate, apatite, etc.), vegetable powders (soybean flour, wheat flour, wood flour, tobacco flour, starch,
(crystalline cellulose, etc.), polymer compounds (petroleum resin, polyvinyl chloride, dammar gum, ketone resin, etc.), alumina, waxes, etc. Examples of liquid carriers include alcohols (methyl alcohol, ethyl alcohol, ethylene glycol, benzyl alcohol, etc.), aromatic hydrocarbons (toluene, benzene, xylene, methylnaphthalene, etc.), chlorinated hydrocarbons (chloroform, carbon tetrachloride, monochlorobenzene, etc.), ethers (dioxane, tetrahydrofuran, etc.), ketones (acetone, methyl ethyl ketone, cyclohexanone, etc.), esters (ethyl acetate, butyl acetate, ethylene glycol acetate, etc.), acid amides (dimethylformamide, etc.) ), nitriles (such as acetonitrile), ether alcohols (such as ethylene glycol ethyl ether), and water. The surfactant used for the purpose of emulsification, dispersion, spreading, etc. may be nonionic, anionic, cationic, or amphoteric. Examples of surfactants used include polyoxyethylene alkyl ether, polyoxyethylene alkylaryl ether, polyoxyethylene fatty acid ester, sorbitan fatty acid ester, polyoxyethylene sorbitan fatty acid ester, oxyethylene oxypropylene polymer, polyoxy Ethylene alkyl phosphate ester, fatty acid salt,
Alkyl sulfate salts, alkyl sulfonates, alkylaryl sulfonates, alkyl phosphate salts, polyoxyethylene alkyl sulfate esters, quaternary ammonium salts, etc.
Of course, it is not limited to these.
In addition, gelatin,
Casein, sodium alginate, starch, agar, polyvinyl alcohol, etc. can be used as adjuvants. Examples of formulations of the herbicide of the present invention are shown below. In addition, the compound name is indicated by the above-mentioned compound number. Formulation Example 1 80 parts by weight of compound (1), 3 parts by weight of alkyl sulfate, 2 parts by weight of lignin sulfonate and 15 parts by weight of white carbon are thoroughly ground and mixed to obtain a wettable powder. Formulation example 2 Compound (2) 20 parts by weight, emulsifier Sorbol 2680 (registered trademark of Toho Chemical) 10 parts by weight, cyclohexanone
50 parts by weight and 20 parts by weight of xylene are thoroughly mixed to obtain an emulsion. Formulation Example 3 0.1 part by weight of compound (2), 1 part by weight of white carbon, 35 parts by weight of bentonite and 63.9 parts by weight of clay are thoroughly ground and mixed, water is added and the mixture is thoroughly kneaded, followed by granulation drying to obtain granules. . Formulation sequence 4 3 parts by weight of compound (3), 0.3 parts by weight of isopropyl phosphate, 66.7 parts by weight of clay and 30 parts by weight of talc are thoroughly ground and mixed to obtain a powder. When using the compounds of the invention by pre-emergence and post-emergence application methods, the application rates can be varied within a fairly wide range. Generally the amount of active compound is from 1 g to 500 g per 10 are, preferably from 2 g to 300 g. Furthermore, the compound of the present invention can be used in combination with other herbicides in order to improve its effectiveness as a herbicide, and in some cases a synergistic effect can be expected. Examples include phenoxy herbicides such as 2,4-dichlorophenoxyacetic acid; 2-methyl-4-chlorophenoxybutyric acid; 2-methyl-4-chlorophenoxyacetic acid (including esters and salts);
2,4-dichlorophenyl-4'-nitrophenyl ether; 2,4,6-trichlorophenyl-
4'-nitrophenyl ether; 2-chloro-4-
Trifluoromethylphenyl-3'-ethoxy-
Diphenyl such as 4'-nitrophenyl ether; 2,4-dichlorophenyl-4'-nitro-3'-methoxyphenyl ether; 2,4-dichlorophenyl-3'-methoxycarbonyl-4'-nitrophenyl ether Ether herbicide, 2-chloro-4,
6-bisethylamino-1,3,5-triazine; 2-chloro-4-ethylamino-6-isopropylamino-1,3,5-triazine; 2-methylthio-4,6-bisethylamino-1, 3,
5-triazine; 2-methylthio-4,6-bisisopropylamino-1,3,5-triazine;
Triazine herbicides such as 4-amino-6-tert-butyl-3-methylthio-1,2,4-triazin-5-one, 3-(3,4-dichlorophenyl)-1,1-dimethylurea; 3 -(3,4
-dichlorophenyl)-1-methoxy-1-methylurea; 1-(2,2-dimethylbenzyl)-3
-p-tolylurea; 1,1-dimethyl-3-
Urea herbicides such as (3-trifluoromethylphenyl)urea, isopropyl N-(3-chlorophenyl)carbamate; carbamate herbicides such as methyl N-(3,4-dichlorophenyl)carbamate, S-(4- Chlorbenzyl)-N,N-
Diethylthiol carbamate; S-ethyl-
N,N-hexamethylenethiol carbamate;
Thiol carbamate herbicides such as S-ethyl-N,N-diisobutylthiol carbamate; S-ethyl-N,N-dinormalpropylthiol carbamate; S-normalpropyl-N,N-dinormalpropylthiol carbamate; 3.
4-dichloropropionanilide; N-methquinmethyl-2,6-diethyl-α-chloroacetanilide; 2-chloro-2',6'-diethyl-N-
(Butoxymethyl)-acetanilide; 2-chloro-2',6'-diethyl-N-(n-propoxyethyl)-acetanilide; N-chloroacetyl-N
-(2,6-diethylphenyl)-glycine ethyl ester; 2-chloro-N-(2-ethyl-6-
Acid anilide herbicides such as methylphenyl)-N-(2-methquin-1-methyl)acetamide, 5-
Bromo-3-secondary butyl-6-methyluracil; uracil-based herbicides such as 3-cyclohexyl-5,6-trimethyleneuracil; pyridinium chlorine-based herbicides such as 1,1'-dimethyl-4,4-bispyridinium chloride; agent, N,N-bis(phosphonomethyl)-glycine, O-ethyl-O-(2
-Nitro-5-methylphenyl)-N-secondary butylphosphoroamidothioate, S-(2
-methyl-1-piperidylcarbonylmethyl)
O,O-di-n-propyldithiophosphate;
Phosphorus herbicides such as S-(2-methyl-1-piperidylcarbonylmethyl)O,O-diphenyldithiophosphate, α,α,α-trifluoro-
Toluidine herbicides such as 2,6-dinitro-N,N-dipropyl-p-toluidine, 5-tert-butyl-3-(2,4-dichloro-5-isopropoxyphenyl) 1,3,4- Oxadiazolin-2-one; 3-isopropyl-1H-2,
1,3-Benzothiadiazin-(4)-3H-one-
2,2-dioxide, α-(β-naphthoxy)-propionanilide, 4-(2,4-dichlorobenzoyl)-1,3-dimethylpyrazole-5-
yl p-toluenesulfonate; 4'-phenylsulfonyl-1,1,1-trifluorosulfono-
o-Toluidide; 4-chloro-5-methylamino-2-(3-trifluoromethylphenyl)pyridazin-3(2H)-one, 1-methyl-3-phenyl-5-(3-trifluoromethylphenyl) enyl)pyridin-4(1H)-one, 2-methyl-4
-Phenylsulfonyltrifluoromethylsulfanilide, 2-(3,4-dichlorophenyl)-4
-Methyltetrahydro-1,2,4-oxadiazole-3,5-dione; 4-chloro-5-methylamino-2-(3-trifluoromethylphenyl)pyridazin-3(2H)-one, etc. However, it is not limited to these. Furthermore, the compound of the present invention can be used in combination with insecticides, nematicides, fungicides, plant growth regulators, fertilizers, etc., if necessary. Next, the present invention will be explained in more detail with reference to Examples, but it goes without saying that the present invention is not limited to these Examples. In each of the following Examples as a herbicide, the evaluation of the phytotoxicity to cultivated plants and the efficacy against weeds was all expressed as an evaluation value using an integer from 0 to 5 in accordance with the criteria described below. Measure the fresh weight of the above-ground parts of the plants that remained withered at the time of the survey, and compare it with the fresh weight of the plants in the untreated area (%)
Calculate. Cultivated plants and weeds were evaluated for chemical damage and herbicidal efficacy on a scale from 0 to 5 based on the criteria shown in the table below. An evaluation value of 0 or 1 for cultivated plants or an evaluation value of 5 or 4 for weeds is generally considered to be an appropriate cultivated plant protection effect or weed control effect.

[Table] In order to further clarify the properties of the present compound, the following compounds were used as comparative compounds. Comparison compound (a)

[Formula] mp153-154℃ Compound (b) of JP-A-52-83686, page 5, table 1, No. 19

[Formula] mp 96.8 to 98.3℃ US Patent No. 3,958,976 Compound within the scope of claims Example 1 Comparative test on efficacy of soil treatment before germination in field field Field soil was packed in a cylindrical plastic beaker with a diameter of 10 cm and a height of 10 cm. Weed seeds of barnyard grass, oat, mulva morning glory, and yamweed were sown. After covering with soil, a predetermined amount of the raw material was made into an emulsion, diluted with water, and the soil was treated with a hand sprayer. Thereafter, the plants were grown in a greenhouse, and the herbicidal efficacy was observed on the 20th day after treatment. The results are shown in Table 2.

【table】

[Table] Example 2 Post-germination foliage treatment efficacy comparative test A cylindrical plastic beaker with a diameter of 10 cm and a height of 10 cm was filled with field soil, and weed seeds of Japanese barnyard grass, oat, wild mustard, and Japanese grass were sown. After covering with soil and growing in a greenhouse for two weeks, a predetermined amount of the chemical was applied to the entire stem and leaves from above using a hand sprayer. After the leaf agent treatment, the plants were grown in a greenhouse for an additional three weeks, and then the herbicidal efficacy of each plant was investigated. The results are shown in Table 3. The processing agent was formulated into an emulsion, a predetermined amount of which was dispersed in water (including a spreading agent), and the test was conducted at a rate of 5 liters per are.

[Table] Example 3 Pre-germination treatment test A plastic tray measuring 35 cm in length, 25 cm in width and 15 cm in height was filled with field soil and planted with field soil, which was then used to plant soil in the field. of weeds, cotton and soybean crops were sown. A predetermined amount of the hydrating agent was dispersed in water, and the entire surface of the soil was sprayed from above the tray using a small sprayer at a rate of 5 liters per area. After treatment, the plants were placed in a greenhouse for 20 minutes and their phytotoxicity and herbicidal efficacy were investigated. The results are shown in Table 4.

[Table] Example 4 Weeding test on corn and wheat (post-emergence treatment) Field soil was packed into plastic trays measuring 35 cm in height, 25 cm in width, and 10 cm in height, and corn, wheat, Japanese yam, Japanese staghorn, Japanese mulberry morning glory, white locust, Japanese brilliance, After sowing chickweed and foxtail grass and growing them in a greenhouse for 2 to 3 weeks,
Arrange two of these trays in a frame measuring 50 cm, width 100 cm, and height 40 cm, and use a small sprayer from above the plants.
A predetermined amount of each drug was applied to the entire area within the frame. After being grown in a greenhouse for an additional three weeks after spraying the chemicals, each plant was examined for chemical damage or herbicidal efficacy. The results are shown in Table 5. The processing agent used was an emulsion prepared according to the recipe in Formulation Example 2, and the emulsion was emulsified in 25 ml of water to which a spreading agent was added. The size of the plants at the time of chemical treatment varied depending on the species, but they were approximately 1.5-20 cm tall at the 1-4 true leaf stage.

【table】

[Table] Example 5 Cyperus rotundus stem and foliage treatment test A plastic pot with a diameter of 10 cm is filled with field soil, tubers of Cyperus rotundus are planted at a depth of 2 cm from the soil surface, grown for 4 weeks in a greenhouse, and leaves are tested. Approximately 7 individual pieces of Japanese porcupine were obtained. A predetermined amount of the raw material was made into an emulsion, diluted with water, and treated with a hand sprayer from above the plants. After the chemical treatment, the soil was grown in a greenhouse for another 8 weeks, and the soil was washed with water to observe the above-ground parts (stem leaves) and the underground regenerated parts (rhizomes and tubers), and the herbicidal efficacy was evaluated as a number from 0 to 5. It was expressed as
The results are shown in Table 6.

【table】

[Table] Example 6 Paddy-like soil treatment test A 1/5000a Wagner pot was filled with Takarazuka paddy soil, seeds of annual weeds were mixed in at a depth of 2 to 3 cm from the soil surface layer, and the pot was flooded with water. After flooding, rice at the four-leaf stage was transplanted, and tubers and overwintering buds of perennial weeds were planted. Five days later, when each weed started to germinate, a predetermined amount of the chemical was dropped onto the water surface using an emulsion. Four weeks after the treatment, herbicidal efficacy and phytotoxicity were investigated, and the results are shown in Table 7.

【table】 [Brief explanation of the drawing]

FIG. 1 is a H-NMR chart showing compound (1), FIG. 2 is a compound (2), and FIG. 3 is a H-NMR chart showing compound (3). The measurement was performed using deuterated chloroform as the solvent, tetramethylsilane as the standard substance, and 60MHz.
It was done by machine. The horizontal axis of the figure represents δ (ppm), and the vertical axis represents the strength of the herbicide.

Claims (1)

[Claims] 1. General formula (In the formula, R represents a lower alkyl group having 1 to 3 carbon atoms.) A substituted phenylhydantoin derivative represented by the following formula. 2 General formula (In the formula, R represents a lower alkyl group having 1 to 3 carbon atoms, and M represents an alkali metal atom.) A substituted phenylhydantoin derivative characterized by ring-closing a urea derivative represented by the following in the presence of a mineral acid. Manufacturing method. 3 General formula (In the formula, R represents a lower alkyl group having 1 to 3 carbon atoms.) Reacting a substituted phenyl isocyanate derivative represented by the formula with an alkali metal salt of pipecolic acid,
general formula (In the formula, R represents a lower alkyl group having 1 to 3 carbon atoms, and M represents an alkali metal atom.) It is characterized by obtaining a urea derivative represented by the following formula, and then ring-closing the compound in the presence of a mineral acid. general formula (In the formula, R represents a lower alkyl group having 1 to 3 carbon atoms.) A method for producing a substituted phenylhydantoin derivative represented by the following formula. 4 General formula (In the formula, R represents a lower alkyl group having 1 to 3 carbon atoms.) A herbicide characterized by containing a substituted phenylhydantoin derivative represented by the following as an active ingredient.