Claims
- 1. A compound of the formula ##STR8## wherein X is a cyano group,
- Y is a hydrogen atom, a halogen atom, or a trifluoromethyl group, and
- Z is a (C.sub.1 -C.sub.4) alkoxy group having one or more hydrogen atoms replaced by a (C.sub.2 -C.sub.4)alkenyl group or a (C.sub.2 -C.sub.4)alkynyl group.
- 2. A compound according to claim 1 wherein Y is a hydrogen atom.
- 3. A compound according to claim 2 wherein Z is a group of the formula ##STR9## wherein Z.sup.1 is a (C.sub.2 -C.sub.4)alkenyl group or a (C.sub.2 -C.sub.4)alkynyl group,
- Z.sup.2 is a hydrogen atom or (C.sub.1 -C.sub.3)alkyl group, and
- n is 0 or 1.
- 4. A compound according to claim 3 wherein Z.sup.2 is a methyl group and n is 0.
- 5. A compound according to claim 2 wherein Z is an allyloxy or (2-propynyl)oxy group.
- 6. A compound according to claim 5 wherein Z is an allyloxy group.
- 7. A compound according to claim 5 wherein Z is a (2-propynyl)oxy group.
- 8. A herbicidal composition which comprises a compound according to claim 1 and an agronomically-acceptable carrier.
- 9. A composition according to claim 8 which also comprises a surfactant.
- 10. A method of controlling weeds which comprises applying to the surface of the growth medium prior to the emergence of the weeds from the growth medium a compound according to claim 1 in an amount sufficient to control the growth of the weeds.
- 11. The method of claim 10 wherein the compound is applied at a rate of about 0.1 to about 12 pounds per acre.
- 12. A method of controlling weeds which comprises applying to weed seedlings a compound according to claim 1 in an amount sufficient to control the growth of the seedlings.
- 13. The method of claim 12 wherein the compound is applied at a rate of about 0.1 to about 12 pounds per acre.
CROSS REFERENCE TO RELATED APPLICATIONS
This is a division of application Ser. No. 881,227 filed Feb. 22, 1978 and now U.S. Pat. No. 4,220,468, which is a division of application Ser. No. 719,484 filed Aug. 31, 1976 and now U.S. Pat. No. 4,093,446, which is a continuation-in-part of application Ser. No. 617,560 filed Sept. 29, 1975 and now U.S. Pat. No. 4,063,929 and also a continuation-in-part of application Ser. No. 617,562 filed Sept. 29, 1975 and now U.S. Pat. No. 4,046,798, which are in turn a continuation-in-part and a division, respectively, of application Ser. No. 331,719 filed Feb. 12, 1973 and now U.S. Pat. No. 3,928,416, which is in turn a continuation-in-part of application Ser. No. 234,651 filed Mar. 14, 1972 and now U.S. Pat. No. 3,798,276.
This invention relates to novel compounds which show activity as herbicides, to novel herbicidal compositions which contain these compounds, and to new methods of controlling weeds with these herbicidal compositions.
Certain diphenyl ethers have been shown to be effective weed control agents. However, the herbicidal effectiveness of a given diphenyl ether cannot be predicted from an examination of the substituent groups attached to the phenyl rings in the ether, and often quite closely related compounds will have quite different weed control abilities. Various diphenyl ethers may have overlapping or complementary areas of activity or selectivity, and can thus be useful in combination to control a variety of weeds upon application of a single composition. Furthermore, the diphenyl ethers heretofore disclosed as herbicides are not completely effective. An ideal herbicide should give selective weed control, over the full growing season, with a single administration at low rates of application. It should be able to control all common weeds by killing them as the seed, the germinating seed, the seedling, and the growing plant. At the same time, the herbicide should not be phytotoxic to the crops to which it is applied and should decompose or otherwise be dissipated so as not to poison the soil permanently. The known diphenyl ether herbicides fall short of these ideals, and it would thus be desirable to have new herbicides which show even more selective control of undesirable plants among desirable crop plants or which complement the known diphenyl ethers in activity.
In accordance with the present invention, there is provided a new class of novel diphenyl ethers having the formula ##STR2## wherein X is a cyano group,
The term "amino group" as used in the present specification and claims is intended to include an unsubstituted amino group, --NH.sub.2, as well as amino groups having one or both hydrogen atoms replaced by substituent groups. Among the substituted amino groups which Z can represent are amino groups substituted with one or two alkyl groups, preferably having a total of up to 6 carbon atoms, halo-, hydroxy-, or alkoxy-substituted alkyl groups, preferably having a total of up to 6 carbon atoms, one or two alkylthio carbonyl groups, preferably having a total of up to 4 carbon atoms in the alkyl moiety, carboxy groups, carbalkoxy groups, preferably having up to 4 carbon atoms in the alkoxy group, carbamoyl groups, including alkyl or dialkylcarbamoyl groups, preferably having up to 4 carbon atoms in the alkyl moiety, alkylcarbonyl groups, preferably having up to 4 carbon atoms, or halo-substituted alkylcarbonyl groups, preferably having up to 4 carbon atoms. The substituted amino groups can also be heterocyclic amino groups, such as piperidino, piperazino, morpholino, pyrrolidinyl, and the like.
When the Z substituent is or contains a carboxy group, either the free acid or the salt form can be used. Typical salts are the agronomically-acceptable metal salts or ammonium salts. Among the metal salts are those in which the metal cation is an alkali metal cation, such as sodium, potassium, lithium, or the like, an alkaline earth metal cation, such as calcium, magnesium, barium, strontium, or the like, or a heavy metal cation, such as zinc, manganese cupric, cuprious, ferric, ferrous, titanium, aluminum or the like. Among the ammonium salts are those in which the ammonium cation has the formula NR.sup.1 R.sup.2 R.sup.3 R.sup.4, wherein each of R.sup.1, R.sup.2, R.sup.3, and R.sup.4 is individually a hydrogen atom, a hydroxy group, a (C.sub.1 -C.sub.4)alkoxy group, a (C.sub.1 -C.sub.20)alkyl group, a (C.sub.3 -C.sub.8)alkenyl group, a (C.sub.3 -C.sub.8)alkynyl group, a (C.sub.2 -C.sub.8),hydroxyalkyl group, a (C.sub.2 -C.sub.8)alkoxyalkyl group, a (C.sub.2 -C.sub.6)aminoalkyl group, a (C.sub.2 -C.sub.6)haloalkyl group, an amino group, a (C.sub.1 -C.sub.4)alkyl- or di(C.sub.1 -C.sub.4)alkylamino group, a substituted or unsubstituted phenyl group, a substituted or unsubstituted phenyl group, a substituted or unsubstituted phenylalkyl group, having up to 4 carbon atoms in the alkyl moiety, or any two of R.sup.1, R.sup.2, R.sup.3, or R.sup.4 can be taken together to form with the nitrogen atom a 5- or 6-member heterocyclic ring, optionally having up to one additional hetero oxygen, nitrogen, or sulfur atom in the ring, and preferably saturated, such as a piperidine, morpholino, pyrrolidino, or piperazino ring, or the like, or any three of R.sup.1, R.sup.2, R.sup.3, or R.sup.4 can be taken together for form with the nitrogen atom a 5- or 6-member aromatic heterocyclic ring, such as a piperazole or pyridine ring. When the ammonium group contains a substituted phenyl or substituted phenylalkyl group, the substituents will generally be selected from halogen atoms, (C.sub.1 -C.sub.8)alkyl groups, (C.sub.1 -C.sub.4)alkoxy groups, hydroxy groups, nitro groups, trifluoromethyl groups, cyano groups, amino groups, (C.sub.1 -C.sub.4)alkylthio groups, and the like. Such substituted phenyl groups preferably have up to two such substituents. Representative ammonium cations include ammonium, dimethylammonium, 2-ethylhexylammonium, bis(2-hydroxyethyl)ammonium, tris(2-hydroxyethyl)ammonium, dicyclohexylammonium, t-octylammonium, 2-hydroxyethylammonium, morpholinium, piperidinium, 2-phenethylammonium, 2-methylbenzylammonium, n-hexylammonium, triethylammonium, trimethylammonium, tri(n-butyl)ammonium, methoxyethylammonium, diisopropylammonium, pyridinium, diallylammonium, pyrazolium, propargylammonium, dimethylhydrazinium, hydroxyammonium, methoxyammonium, dodecylammonium, octadecylammonium, 4-dichlorophenylammonium, 4-nitrobenzylammonium, benzyltrimethylammonium, 2-hydroxyethyldimethyloctadecylammonium, 2-hydroxyethyldiethyloctylammonium, decyltrimethylammonium, hexyltriethylammonium, 4-methylbenzyltrimethylammonium, and the like.
When Z is an alkyl group, it may be optionally substituted with a hydroxy group, a (C.sub.1 -C.sub.4)alkoxy group, or a halogen atom, preferably a chlorine atom.
These novel compounds have been found to show unexpected activity as weed control agents. In a preferred embodiment of the invention, X is a halogen atom or a cyano group, Y is a hydrogen atom or a halogen atom, and Z is an alkoxy group.
Examples of the compounds of the invention embraced by Formula I include:
The novel diphenyl esters of the invention are useful both as preemergence and as postemergence herbicides. Preemergence herbicides are ordinarily used to treat the soil in which the desired crop is to be planted by application either before seeding, during seeding, or, as in most applications, after seeding and before the crop emerges. Postemergence herbicides ae those which are applied after the plants have emerged and during their growth period.
Among the crops on which the diphenyl ethers of the invention can be advantageously employed are, for example, cotton, soybeans, peanuts, safflower, beans, peas, carrots, corn, wheat, and other cereal crops.
Diphenyl ethers of the invention are useful for controlling weeds in rice crops. When used in transplanted rice crops, the ethers can be applied either preemergence or postemergence to the weeds--that is, they can be applied to the growth medium of the transplanted plants either before the weed plants have emerged or while they are in the their early stages of growth. The ethers can be applied to the growth medium either before or after the rice has been transplanted to that medium.
The diphenyl ethers of the invention can be applied in any amount which will give the required control of weeds. A preferred rate of application of the herbicides of the invention is from about 0.1 to about 12, and most preferably about 0.25 to 4, pounds of the diphenyl ether per acre.
Under some conditons, the diphenyl ethers of the invention may be advantageously incorporated into the soil or other growth medium prior to planting a crop. This incorporation can be carried out by any convenient means, including by simple mixing with the soil, by applying the diphenyl ether to the surface of the soil and then disking or dragging into the soil to the desired depth, or by employing a liquid carrier to accomplish the necessary penetration and impregnation.
A diphenyl ether of the invention can be applied to the growth medium or to plants to be treated either by itself or, as is generally done, as a component in a herbicidal composition or formulation which also comprises an agronomically acceptable carrier. By agronomically acceptable carrier is meant any substance which can be used to dissolve, disperse, or diffuse a herbicidal compound in the composition without impairing the effectiveness of the herbicidal compound and which by itself has no detrimental effect on the soil, equipment, crops, or agronomic environment. Mixtures of the diphenyl ethers of the invention may also be used in any of these herbicidal formulations. The herbicidal compositions of the invention can be either solid or liquid formulations or solutions. For example, the diphenyl ethers can be formulated as wettable powders, emulsifiable concentrates, dusts, granular formulations, aerosols, or flowable emulsion concentrates. In such formulations, the compounds are extended with a liquid or solid carrier and, when desired, suitable surfactants are incorporated.
It is usually desirable, particularly in postemergence applications, to include adjuvants, such as wetting agents, spreading agents, dispersing agents, stickers, adhesives, and the like, in accordance with agricultural practices. Examples of adjuvants which are commonly used in the art can be found in the John W. McCutcheon, Inc. publication "Detergents and Emulsifiers Annual".
The diphenyl ether compounds of this invention can be dissolved in any appropriate solvent. Examples of solvents which are useful in the practice of this invention include alcohols, ketones, aromatic hydrocarbons, halogenated hydrocarbons, dimethylformamide, dioxane, dimethyl sulfoxide, and the like. Mixtures of these solvents can also be used. The concentration of the solution can vary from about 2% to about 98% with a preferred range being about 25% to about 75%.
For the preparation of emulsifiable concentrates, the diphenyl ether can be dissolved in organic solvents, such as benzene, toluene, xylene, methylated naphthalene, corn oil, pine oil, o-dichlorobenzene, isophorone, cyclohexanone, methyl oleate, and the like, or in mixtures of these solvents, together with an emulsifying agent which permits dispersion in water. Suitable emulsifiers include, for example, the ethylene oxide derivatives of alkylphenols or long-chain alcohols, mercaptans, carboxylic acids, and reactive amines and partially esterified polyhydric alcohols. Solvent-soluble sulfates or sulfonates, such as the alkaline earth salts or amine salts of alkylbenzenesulfonates and the fatty alcohol sodium sulfates, having surface-active properties can be used as emulsifiers either alone or in conjunction with an ethylene oxide reaction product. Flowable emulsion concentrates are formulated similarly to the emulsifiable concentrates and include, in addition to the above components, water and a stabilizing agent such as a water-soluble cellulose derivative or a water-soluble salt of a polyacrylic acid. The concentration of the active ingredient in emulsifiable concentrates is usually about 10% to 60% and in flowable emulsion concentrates, this can be as high as about 75%.
Wettable powders suitable for spraying, can be prepared by admixing the compound with a finely divided solid, such as clays, inorganic silicates and carbonates, and silicas and incorporating wetting agents, sticking agents, and/or dispersing agents in such mixtures. The concentration of active ingredients in such formulations is usually in the range of about 20% to 98%, preferably about 40% to 75%. A dispersing agent can constitute about 0.5% to about 3% of the composition, and a wetting agent can constitute from about 0.1% to about 5% of the composition.
Dusts can be prepared by mixing the compounds of the invention with finely divided inert solids which may be organic or inorganic in nature. Materials useful for this purpose include, for example, botanical flours, silicas, silicates, carbonates and clays. One convenient method of preparing a dust is to dilute a wettable powder with a finely divided carrier. Dust concentrates containing about 20% to 80% of the active ingredient are commonly made and are subsequently diluted to about 1% to 10% use concentration.
Granular formulations can be prepared by impregnating a solid such as granular fuller's earch, vermiculite, ground corn cobs, seed hulls, including bran or other grain-hulls, or similar material. A solution of one or more of the diphenyl ethers in a volatile organic solvent can be sprayed or mixed with the granular solid and the solvent then removed by evaporation. The granular material can have may suitable size, with a preferable size range of 16 to 60 mesh. The diphenyl ether will usually comprise about 2 to 15% of the granular formulation.
The diphenyl ethers of the invention can also be mixed with fertilizers or fertilizing materials before their application. In one type of solid fertilizing composition in which the diphenyl ethers can be used, particles of a fertilizer or fertilizing ingredients, such as ammonium sulfate, ammonium nitrate, or ammonium phosphate, can be coated with one or more of the ethers. The solid diphenyl ethers and solid fertilizing material can also be admixed in mixing or blending equipment, or they can be incorporated with fertilizers in granular formulations. Any relative proportion of diphenyl ether and fertilizer can be used which is suitable for the crops and weeds to be treated. The diphenyl ether will commonly be from about 5% to about 25% of the fertilizing composition. These compositions provide fertilizing materials which promote the rapid growth of desired plants, and at the same time control the growth of undesired plants.
The diphenyl ethers of the invention can be applied as herbicidal sprays by methods commonly employed, such as conventional high-gallonage hydraulic sprays, low gallonage sprays, airblast spray, aerial sprays and dusts. For low volume applications a solution of the compound is usually used. The dilution and rate of application will usually depend upon such factors as the type of equipment employed, the method of application, the area to be treated and the type and stage of development of the weeds.
For some applications, it may be desirable to add one or more other herbicides along with diphenyl ethers of the invention. Examples of other herbicides which can be incorporated to provide additional advantages and effectiveness include:
The diphenyl ethers of the invention or their precursers can be prepared by reacting a suitably substituted phenol, or the potassium or sodium salt of the phenol, with a suitably substituted halobenzene, such as a chloro- or fluorobenzene in the presence of an alkaline agent. In addition, the substituted alkoxy diphenyl ethers or their precursors can be prepared by reacting the corresponding diphenyl ether precursor in which Z in Formula I is a good leaving group, such as a halogen atom, preferably a chlorine atom, a substituted phenoxy group, such as a 2-chloro-4-trifluoromethylphenoxy group, or the like, with an appropriate substituted carbinol, such as a carbinol of the formula ##STR3## wherein Z.sup.1, Z.sup.2, and n are as defined above. This reaction is generally carried out at a temperature of about 0.degree. to about 200.degree. C. The reaction can be carried out in any inert, preferably nonpolar, solvent in which the reactants are at least partially soluble, including benzene, dioxane, and the like, and usually in the presence of a base such as potassium hydroxide, potassium carbonate, or the like.
Diphenyl ethers prepared by the above techniques can also be used as precursors in preparing compounds of the invention. For example, the compounds of the invention in which Z is hydroxy may be converted to the .alpha.-oxymethylene carboxylic esters by condensation with .alpha.-halo esters in the presence of bases such as potassium carbonate or hydroxide to give compounds in which Z.sup.1 is carbalkoxy. These esters in turn may be converted by conventional techniques to the corresponding carboxylic acids, acid chlorides and amides. Other typical postreactions include the oxidation, for example using peracid, of 2-methylthioethoxy to 2-methylsulfonylethoxy and the hydration, for example using mercuric ion, of (1-ethynyl)ethoxy to 1-acetylethoxy, and the like. In addition, compounds of the invention can be made by nitration of suitable precursors without a nitro group prepared by the above techniques.
The salts of the invention can be prepared by any convenient art-recognized method, such as by reacting a metal hydroxide, a metal hydride, or an amine or ammonium salt, such as a halide, hydroxide, or alkoxide, with the free acid, or reacting a quaternary ammonium salt, such as a chloride, a bromide, nitrate, or the like with a metal salt of the invention in a suitable solvent. When metal hydroxides are used as reagents, useful solvents include water, glyme, dioxane, tetrahydrofuran, methanol, ethanol, isopropanol and the like. When metal hydrides are used as reagents, useful solvents include nonhydroxylic solvents such as dioxane, glyme, tetrahydrofuran, diethyl ether, hydrocarbon, including toluene, benzene, xylene, hexane, pentane, heptane, and octane, dimethylformamide, and the like. When amines are used as reagents, useful solvents include alcohols, such as methanol or ethanol, hydrocarbons, such as benzene, toluene, xylene, hexane, and the like, tetrahydrofuran, glyme, dioxane, or water. When ammonium salts are used as reagents, useful solvents include water, alcohols, such as methanol or ethanol, glyme, tetrahydrofuran, or the like. When the ammonium salt is other than a hydroxide or alkoxide, an additional base, such as a potassium or sodium hydroxide, hydride, or alkoxide is generally used. The particular choice of solvent will depend on the relative solubilities of the starting materials and the resultant salts, and slurries rather than solutions, of certain reagents may be used to obtain the salts. Generally, equivalent amounts of the starting reagents are used and the salt-forming reaction is carried out at about 0.degree. to about 100.degree. C., and preferably at about room temperature.
US Referenced Citations (11)
Divisions (3)
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Number |
Date |
Country |
| Parent |
881227 |
Feb 1978 |
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| Parent |
331719 |
Feb 1973 |
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| Parent |
719484 |
Aug 1976 |
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Continuation in Parts (2)
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Number |
Date |
Country |
| Parent |
234651 |
Mar 1972 |
|
| Parent |
617560 |
Sep 1975 |
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Patent Grant
4330324
