Information
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Patent Grant
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5481022
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Patent Number
5,481,022
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Date Filed
Tuesday, July 19, 199430 years ago
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Date Issued
Tuesday, January 2, 199629 years ago
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Inventors
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Original Assignees
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Examiners
- Dees; Jose G.
- Frazier; Barbara S.
Agents
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CPC
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US Classifications
Field of Search
US
- 504 315
- 560 45
- 562 455
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International Classifications
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Abstract
The invention provides N-aryloxyacyl-N-phenyltetrahydrophthalamic acid derivatives represented by the general formula [I], a method of producing the same, and a herbicide containing the same as the effective components, ##STR1## wherein X and Y each individually represent hydrogen atoms or halogen atoms, Ar represents a substituted or unsubstituted phenyl group or naphthyl group, R.sup.1 represents a hydrogen atom, a halogen atom, a lower alkyl group, a lower alkoxy group, a lower alkenyloxy group, a lower alkynyloxy group, a lower alkoxyalkoxy group or a lower alkoxycarbonylalkoxy group, R.sup.2 represents a hydrogen atom or a lower alkyl group, R.sup.3 represents a hydroxyl, a lower alkoxy group, a lower alkenyloxy group, a lower alkynyloxy group, a lower alkoxyalkoxy group, a benzyloxy group or a lower alkoxycarbonylalkoxy group, and m is an integer ranging from 0 to 5. This herbicide which is very useful can be widely applied to upland, paddy field, orchard, turf, forest, non-crop land, etc., and is not harmful to crops.
Description
This application is a 371 of PCT/JP93/01756, filed Dec. 2, 1993.
TECHNOLOGICAL FIELD
This invention relates to herbicides, and more particularly to N-aryloxyacyl-N-phenyltetrahydrophthalamic acid derivatives which are novel compounds, to methods of producing the same and to herbicides containing the same as the effective components. N-aryloxyacyl-N-phenyl-tetrahydrophthalamic acid derivatives of the present invention exhibit excellent herbicidal activity. The derivatives are useful as a herbicide which can be widely applied to upland, paddy field, orchard, pasture, turf, forest, non-crop land, etc. The derivatives are not harmful to crops.
BACKGROUND TECHNOLOGY
Hitherto, herbicidal activity of tetrahydrophthalamic acid derivatives has been well known. For example, N-(4'-chlorophenyl)-3, 4, 5, 6.tetrahydrophthalamic acid methyl ester is known, as is disclosed in JP-A (Patent) 48-44425.
However, the conventional tetrahydrophthalamic acid derivatives are not necessarily sufficient in herbicidal activity, or are substantially limited in herbicidal spectrum against weeds. Furthermore, these derivatives are insufficient in selectivity between crops and weeds, thereby inducing problems of safety for crops. Compounds disclosed in JP-A (Patent) 4-803407 are known as those solving these problems and exhibiting excellent herbicidal activity. However, there is no description about compounds having N-aryloxyacyl group in N-acyl group part nor about biological activity of these compounds.
It is an object of the present invention to solve the aforementioned conventional problems, and to provide N-aryloxyacyl-N-phenyltetrahydrophthalamic acid derivatives as novel compounds exhibiting excellent herbicidal activity against various very harmful weeds and not being harmful to crops, methods of producing the same and herbicides containing the same as the effective components.
DISCLOSURE OF THE INVENTION
The inventors have found that novel tetrahydrophthalamic acid derivatives each having a specific substituent aryloxyacyl group bonded to an amide nitrogen atom are very excellent in herbicidal activity, selectivity and herbicidal spectrum, and completed the present invention.
The present invention provides N-aryloxyacyl-N-phenyltetrahydrophthalamic acid derivatives represented by the general formula [I], methods of producing the same, and herbicides containing the same as the effective components: ##STR2## wherein X and Y each individually represent hydrogen atoms or halogen atoms, Ar represents a substituted or unsubstituted phenyl group or naphthyl group, R.sup.1 represents a hydrogen atom, a halogen atom, a lower alkyl group, a lower alkoxy group, a lower alkenyloxy group, a lower alkynyloxy group, a lower alkoxyalkoxy group or a lower alkoxycarbonylalkoxy group, R.sup.2 represents a hydrogen atom or a lower alkyl group, R.sup.3 represents a hydroxyl, a lower alkoxy group, a lower alkenyloxy group, a lower alkynyloxy group, a lower alkoxyalkoxy group, a benzyloxy group or a lower alkoxycarbonylalkoxy group, and m is an integer ranging from 0 to 5.
N-aryloxyacyl-N-phenyltetrahydrophthalamic acid derivatives [I] as compounds of the present invention can be synthesized, for example, by the following method.
Firstly, imidoylchloride derivatives represented by the general formula [III] are obtained as an intermediate product by reacting a dehydrochlorinating agent such as polymer-carried triphenylphosphine and carbon tetrachloride with anilide derivatives represented by the general formula [II] without using any solvent, or in a solvent such as methylene chloride, chloroform, benzene, toluene, xylene, ethyl acetate, ether, dioxane, tetrahydrofuran, N,N-dimethylformamide, N,N-dimethylacetamide, dimethyl sulfoxide or sulfolane, at a temperature ranging from 0.degree. C. to 200.degree. C. and preferably from 0.degree. C. to 100 .degree. C.
Then, a carboxylic acid represented by the general formula [IV] and a suitable deacidifying agent such as an organic base such as triethylamine or pyridine or an inorganic base such as potassium hydroxide or sodium hydroxide are reacted with the imidoylchloride derivatives represented by the general formula [III], after the isolation and purification of the imidoylchloride derivatives or without the isolation and purification of the same, without using any solvent or in a solvent such as methylene chloride, chloroform, benzene, toluene, xylene, cumene, ethyl acetate, ether, dioxane, tetrahydrofuran, N,N-dimethylformamide, N,N-dimethylacetamide, dimethyl sulfoxide, sulfolane, acetone or methylethylketone, at a temperature ranging from -20.degree. C. to 250.degree. C. and preferably from 0 .degree. C. to 100.degree. C., thereby synthesizing N-aryloxyacyl-N-phenyl-tetrahydrophthalamic acid derivatives [I] which are compounds of the present invention. ##STR3## wherein X and Y each individually represent hydrogen atoms or halogen atoms, Ar represents a substituted or unsubstituted phenyl group or naphthyl group, R.sup.1 represents a hydrogen atom, a halogen atom, a lower alkyl group, a lower alkoxy group, a lower alkenyloxy group, a lower alkynyloxy group, a lower alkoxyalkoxy group or a lower alkoxycarbenylalkoxy group, R.sup.2 represents a hydrogen atom or a lower alkyl group, R.sup.3 represents a hydroxyl, a lower alkoxy group, a lower alkenyloxy group, a lower alkynyloxy group, a lower alkoxyalkoxy group, a benzyloxy group or a lower alkoxycarbonylalkoxy group, and m is an integer ranging from 0 to 5.
As preferable examples of the dehydrochlorinating agent used in the reaction, phosphorus pentachloride, phosphorus trichloride-chlorine, thionyl chloride, arylsulfonylchloride, phosgene, triphenylphosphine-carbon tetrachloride as well as polymer-carried triphenyl-phosphine-carbon tetrachloride can be cited.
Furthermore, as preferable examples of the solvent used in the reaction, halogenated hydrocarbons such as dichloroethane, carbon tetrachloride, chloroform and methylene chloride, aromatic hydrocarbons such as benzene, toluene, xylene and chlorobenzene, and polar solvents such as acetonitrile and dimethyl sulfoxide can be cited.
Anilide derivatives [II] which are necessary as a starting material to obtain N-aryloxyacyl-N-phenyltetrahydrophthalamic acid derivatives [I] which are compounds of the present invention can be easily produced, for example, by the following method.
That is, anilide derivatives [II] can be easily obtained by reacting aniline derivatives represented by the general formula [V] with aryloxycarboxylic acid derivatives represented by the general formula [VI], ##STR4## wherein X and Y each individually represent hydrogen atoms or halogen atoms, and R.sup.1 represents a hydrogen atom, a halogen atom, a lower alkyl group, a lower alkoxy group, a lower alkenyloxy group, a lower alkynyloxy group, a lower alkoxyalkoxy group or a lower alkoxycarbonylalkoxy group, ##STR5## wherein Ar represents a substituted or unsubstituted phenyl group or naphthyl group, R.sup.2 represents a hydrogen atom or a lower alkyl group, m is an integer ranging from 0 to 5, and Z represents a hydroxyl or a halogen atom.
THE BEST MODE TO CARRY OUT THE INVENTION
Hereinafter, the present invention will be described concretely with reference to Examples.
EXAMPLE 1.
Synthesis of N-phenoxyacetyl-N- [2-fluoro-4-chloro-5- (1-methylpropargloxy)phenyl]-3,4,5,6-tetrahydrophthalamic acid methyl ester (A compound which is represented by No. 1 in Table 1 and by the general formula [I])
First, 3.07 g of N- [2-fluoro-4-chloro-5- (1-methylpropargyloxy)phenyl]-phenoxyacetamide, 9.00 g of polystyrene-carried triphenylphosphine (3 mmol/g) and 10 ml of carbon tetrachloride were mixed in 45 ml of 1,2-dichloroethane, and then the reflux under heat was continued for 3.5 hr. After letting the solution stand to cool the same, polystyrene was filtered out. The solvent of the filtrate was distilled out under reduced pressure. Then, 1.66 g of 3,4,5,6-tetrahydrophthalamic acid monomethyl ester and 35 ml of benzene were added to the residue. 0.91 g of triethylamine dissolved in 5 ml of benzene was dropped into the solution at room temperature. stirring was continued for 4 hr at a temperature of 70 .degree. C. After letting the mixture stand to cool the same, it was poured into iced water, and then the organic layer was separated therefrom and washed with water. Then, it was dried with anhydrous magnesium sulfate. The solvent was distilled out. Then, the residue was purified by silica gel column chromatography (effluent: methylene chloride/n-hexane (v/v)=4/1) to obtain 1.20 g of N-phenoxyacetyl-N-[2-fluoro-4-chloro-5-(1-methylpropargyloxy)phenyl]-3,4,5,6-tetrahydrophthalamic acid methyl ester as a solid matter.
Table 1 shows N-aryloxyacyl-N-phenyltetrahydrophthalamic acid derivatives [I] which are compounds of the present inventions, each of which was obtained by a process analogous to the above process, and Table 2 shows .sup.1 H-NMR absorption spectrum values thereof. However, the compounds of the present invention are not limited to those shown in Table 1.
The compound Nos. in Tables 1 and 2 will be employed in the following examples and experiments.
TABLE 1______________________________________ ##STR6##Compound No. R.sup.2 Ar Form______________________________________1 H ##STR7## oil-like substance2 H ##STR8## oil-like substance3 CH.sub.3 ##STR9## solid matter4 H ##STR10## oil-like substance______________________________________
TABLE 2______________________________________Com-poundNo. .sup.1 H-NMR Absorption Spectrum Values .delta. (ppm,______________________________________ CDCl.sub.3)1 1.5.about.1.8(m, 4H), 1.70(d, J=6.6Hz, 3H), 2.1.about.2.5(m, 4H), 2.43(d, J=2.0Hz, 1H), 3.77(s, 3H), 4.6.about.5.2(m, 3H), 6.8.about.7.0(m, 3H), 7.1.about.7.4(m, 4H)3 1.5.about.1.8(m, 10H), 2.2.about.2.6(m, 5H), 3.76(s, 3H), 4.7.about.4.9 (m, 2H), 6.8.about.7.4(m, 7H)4 1.6.about.1.8(m, 4H), 1.70(d, J=6.4Hz, 3H), 2.3.about.2.6(m, 5H), 3.76(s, 3H), 4.7.about.5.1(m, 3H), 6.8.about.7.0(m, 4H), 7.1.about.7.3 (m, 5H)______________________________________
A herbicide of the present invention containing N-aryloxyacyl-N-phenyltetrahydrophthalamic acid derivatives [I] as the effective components, which are compounds of the present invention, has a superior herbicidal activity against various weeds causing problems upon the submerged soil treatment in paddy fields, such as gramineous weeds such as nobie (barnyardgrass, Echinochloa spp.), broad-leaved weeds such as azena (flase pimpernel, Lindernia pyxidaria), kikashigusa (toothcup, Rotala indica), mizohakobe (waterwort, Elatine triandra), cyperaceous weeds such as tamagayatsuri (small-flowered umbrellaplant, Cyperus difformis) and hotarui (bulrush, Scirpus juncoides), and weeds such as konagi (Monochoria vaginalis). Furthermore, the herbicide has a superior herbicidal activity against various weeds causing problems upon the foliage treatment and the soil treatment in uplands, such as broad-leaved weeds such as karashina (indian mustard, Brassica juncea), aobiyu (slender amaranth, Amaranthus viridis), hakobe (chickweed, Stellaria media), shiroza (common lambsquarters, Chenopodium album), onamomi (heartleaf cocklebur, Xanthium strumarium), maruba-asagao (tall morningglory, Ipomoea purpurea), yaemugura (catchweed bedstraw, Galium aparine), suberihiyu (common purslane, Portulaca oleracea), ichibi (velvetleaf, Abutilon theophrasti) , amerika-tsunokusanemu (hemp sesbania, Sesbania exaltata), ebisugusa (sicklepod, Cassia obtusifolia), inuhouzuki (black nightshade, Solanum nigrum), spedwells, smart weeds, violets, tade (Persicaria longiseta) and its relatives, and sumire (Viola mandshurica) and its relatives, gramineous weeds such as inubie (barnyardgrass, Echinochloa crus-galli), enokorogusa (green foxtail, Setaria viridis), karasumugi (wild oat, Avena fatua), mehishiba (henry crabgrass, Digitaria ciliaris), seibanmorokoshi (johnsongrass, Sorghum halepense) and enbaku (oat, Avena sativa), cyperaceous weeds such as kogomegayatsuri (rice flatsedge, Cyperus iria) and hamasuge (nut grass, Cyperus rotundus), and commelinaceous weeds such as tsuyukusa (dayflower, Commelina communis). The herbicide of the present invention hardly injures major crops such as rice, wheat, corn and soybean.
Therefore, the herbicide of the present invention can be widely applied to upland, paddy field, orchard, pasture, turf, forest and non-crop land.
It is possible to process the herbicide of the present invention containing N-aryloxyacyl-N-phenyl-tetrahydrophthalamic acid derivatives [I] which are the above compounds of the present invention as the effective components into an arbitrary form such as wettable powder, emulsion, granules, powder or flowable by using a pesticide adjuvant which is generally used in this field, such as an inactive solid carrier or liquid carrier and/or an emulsifying and dispersing agent and the like. As the inactive carriers, for example, talc, clay, bentonire, kaolin, diatomaceous earth, calcium carbonate, wood flour, starch, gum arabic, water, alcohol, kerosene, benzene, xylene, n-hexane, acetone, N,N-dimethylformamide, glycol ether, N-methyl-pyrrolidone can be cited.
Besides, it is possible to adequately incorporate auxiliary agents for formulation, such as spreader, diluent, surfactant and solvent.
Upon using N-aryloxyacyl-N-phenyltetrahydrophthalamic acid derivatives [I] which are compounds of the present invention as a herbicide, a suitable application dosage is variable according to related factors such as manner of application, object of application, time of application and occurrence condition of weeds, but in general the application dosage, as expressed as the amount of the effective component, is preferably from 0.1 g to 300 g, and particularly preferably from 1 g to 300 g, per 10 ares. If it is not greater than 0.1 g, a sufficient herbicidal effect can not be obtained. If it is not less than 300 g, it becomes unfavorable because it not only is economically disadvantageous but also may cause the occurrence of phytotoxicity.
Furthermore, to use the herbicide containing N-aryloxyacyl-N-phenyltetrahydrophthalamic acid derivatives [I] which are compounds of the present invention, it may be mixed with other herbicides, plant growth regulators, fungicides, insecticides, other pesticides, fertilizers and soil conditioners.
The following are Examples of herbicides according to the present invention, though compounds, carriers, adjuvants and the proportions of the ingredients are not limited to those in these examples. In these examples, the amount of each component is indicated by parts by weight.
EXAMPLE 2 (Wettable Powder)
______________________________________Compound No. 1 10 partsSodium lignin sulfonate 1.5 partsPolyoxyethylene alkylaryl ether 1.5 partsClay 87 parts______________________________________
These materials were mixed together until a uniform mixture was obtained, and the mixture was pulverized to obtain a wettable powder.
EXAMPLE 3 (Granules)
______________________________________Compound No. 1 7 partsBentonice 30 partsSodium alkylsulfonate 2 partsClay 61 parts______________________________________
These materials were mixed together and kneaded until a uniform mixture was obtained, and the mixture was granulated by an ordinary granulation method thereby to obtain granules.
EXAMPLE 4 (Emulsion)
______________________________________Compound No. 1 5 partsN-methylpyrrolidone 44 partsSolpol 7065 43 parts(product of Toho Kagaku Kogyo Co., Ltd.)Solpol 355 8 parts(product of Toho Kagaku Kogyo Co., Ltd.)______________________________________
These materials were mixed together until a uniform mixture was obtained, thereby to obtain an emulsion.
The following experiments are illustrative of the herbicidal effects of N-aryloxyacyl-N-phenyltetrahydrophthalamic derivatives [I] which are compounds of the present invention.
EXPERIMENT 1 (Flooded Soil Treatment)
Paddy soil (clay loam) was put into a pot so as to have a surface area of 1/15500 ares. Uniformly mixed seeds of several kinds of weeds, viz., nobie (barnyardgrass, Echinochloa spp.), broad-leaved weeds, hotarui (bulrush, Scirpus juncoides), tamagayacsuri (small-flowered umbrellaplant, Cyperus difformis) and konagi (monochoria, Monochoria vaginalis), were sown in the surface layer of the soil in each pot, and then paddy rice seedlings at the two- or three-leaved stage were transplanted into each pot to a depth of 2 cm, and water was fed into each pot so as to provide a 3 cm deep water layer on the soil surface. After 3 days, in other words, at the initial stage of germination of nobie (barnyardgrass, Echinochloa spp.), a predetermined amount of a selected compound in the form of diluted aqueous solution was dropped into the water layer in each pot. After that, the pots were kept in a glass chamber to allow the paddy rice and the weeds to grow, and after the lapse of 4 weeks from the treatment with the selected compounds, the herbicidal effects and the degree of injury to the paddy rice were evaluated. The results are shown in Table 3. In the table, the herbicidal effects and the degree of injury to the paddy rice are indicated by numerical values, which have the following meaning.
5: completely killed
4: seriously injured
3: considerably injured
2: somewhat injured
1: slightly injured
0.5: very slightly injured
0: not injured (normally grown)
EXPERIMENT 2 (Foliage Treatment)
Upon seedling stage (two- or three-leaved stage) of rice, cockspur (Panicum crus-galli), garden radish, aobiyu (slender amaranth, Amaranthus viridis) and mehishiba (henry crabgrass, Digitaria cliaris) which were grown on a cultivated soil put in pots of 1/15500 ares, a selected compound in suspended wettable powder was sprayed to each plant. After that, the pots were kept in a glass chamber to allow each plant to grow, and after the lapse of 4 weeks from the treatment with the selected compounds the herbicidal effects were evaluated. The results are shown in Table 4. The evaluation of the herbicidal effects was similarly conducted as to that of Experiment 1.
TABLE 3__________________________________________________________________________Quantity Of Injury Herbicidal EffectCompound Compound of broad-leaved tamagaya-No. g/10a Paddy nobie weed hotarui tsuri konagi__________________________________________________________________________1 6.25 0.5 5 5 4 5 5 3.125 0.5 5 5 4 5 52 6.25 0.5 5 5 3 5 5 3.125 0.5 5 5 3 5 53 6.25 0.5 5 5 5 5 5 3.125 0 5 5 5 5 54 6.25 0.5 5 5 4 5 5 3.125 0 5 5 3 5 5Compara- 6.25 0 4 4 4 5 5tive 3.125 0 2 3 1 5 5agent A__________________________________________________________________________ Comparative agentA: MO
TABLE 4______________________________________ Quanti- ty ofCom- Com-pound pound gardenNo. g/10a rice cockspur radish aobiyu mehishiba______________________________________1 16 1 1 5 5 1 8 1 1 5 5 12 16 1 1 5 5 1 8 1 0 5 5 03 16 1 0 5 5 1 8 1 0 5 5 14 16 2 0 4 5 0 8 1 0 3 5 0Com- 16 0 0 5 5 0parative 8 0 0 5 5 0agent B______________________________________ Comparative agentB: Propanil
INDUSTRIAL APPLICABILITY
N-aryloxyacyl-N-phenyltetrahydrophthalamic acid derivatives of the present invention, which are novel compounds, exhibit excellent herbicidal activity, and are useful as a herbicide which can be widely applied to upland, paddy field, orchard, turf, forest, non-crop land, etc., and which is not harmful to crops.
Claims
- 1. An N-aryloxyacyl-N-phenyltetrahydrophthalamic acid derivative represented by the general formula [I], ##STR11## wherein X and Y each individually represent hydrogen atoms or halogen atoms, Ar represents a substituted or unsubstituted phenyl group or naphthyl group, R.sup.1 represents a hydrogen atom, a halogen atom, a lower alkyl group, a lower alkoxy group, a lower alkenyloxy group, a lower alkynyloxy group, a lower alkoxyalkoxy group or a lower alkoxycarbonylalkoxy group, R.sup.2 represents a hydrogen atom or a lower alkyl group, R.sup.3 represents a hydroxyl, a lower alkoxy group, a lower alkenyloxy group, a lower alkynyloxy group, a lower alkoxyalkoxy group, a benzyloxy group or a lower alkoxycarbonylalkoxy group, and m is an integer ranging from 0 to 5.
- 2. A herbicide comprising, as an effective component, an N-aryloxyacyl-N-phenyltetrahydrophthalamic acid derivative which is represented by the general formula [I], ##STR12## wherein X and Y each individually represent hydrogen atoms or halogen atoms, Ar represents a substituted or unsubstituted phenyl group or naphthyl group, R.sup.1 represents a hydrogen atom, a halogen atom, a lower alkyl group, a lower alkoxy group, a lower alkenyloxy group, a lower alkynyloxy group, a lower alkoxyalkoxy group or a lower alkoxycarbonylalkoxy group, R.sup.2 represents a hydrogen atom or a lower alkyl group, R.sup.3 represents a hydroxyl, a lower alkoxy group, a lower alkenyloxy group, a lower alkynyloxy group, a lower alkoxyalkoxy group, a benzyloxy group or a lower alkoxycarbonylalkoxy group, and m is an integer ranging from 0 to 5.
- 3. A herbicide according to claim 2, which is in the form of a wettable powder comprising an inactive carrier.
- 4. A herbicide according to claim 2, which is in the form of granules comprising an inactive carrier.
- 5. A herbicide according to claim 2, which is in the form of an emulsion comprising an inactive carrier.
- 6. A herbicide according to claim 2, wherein said N-aryloxyacyl-N-phenyltetrahydrophthalamic acid derivative is N-phenoxyacetyl-N-[2-fluoro-4-chloro-5-(1-methylpropargyloxy)phenyl]-3,4,5,6-tetrahydrophthalamic acid methyl ester.
- 7. A herbicide according to claim 2, wherein said N-aryloxyacyl-N-phenyltetrahydrophthalamic acid derivative is N-(2,4-dichlorophenoxy)acetyl-N-[2-fluoro-4-chloro-5-(1-methylpropargyloxy)phenyl]-3,4,5,6-tetrahydrophthalamic acid methyl ester.
- 8. A herbicide according to claim 2, wherein said N-aryloxyacyl-N-phenyltetrahydrophthalamic acid derivative is N-2-phenoxypropionyl-N-[2-fluoro-4-chloro-5-(1-methylpropargyloxy)phenyl]-3,4,5,6-tetrahydrophthalamic acid methyl ester.
- 9. A herbicide according to claim 2, wherein said N-aryloxyacyl-N-phenyltetrahydrophthalamic acid derivative is N-.beta.-naphthoxyacetyl-N-[2-fluoro-4-chloro-5-(1-methylpropargyloxy)phenyl]-3,4,5,6-tetrahydrophthalamic acid methyl ester.
Priority Claims (1)
Number |
Date |
Country |
Kind |
4-323468 |
Dec 1992 |
JPX |
|
PCT Information
Filing Document |
Filing Date |
Country |
Kind |
102e Date |
371c Date |
PCT/JP93/01756 |
12/2/1993 |
|
|
7/19/1994 |
7/19/1994 |
Publishing Document |
Publishing Date |
Country |
Kind |
WO94/12469 |
6/9/1994 |
|
|
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