2-NITRO-5-(SUBSTITUTED-PHENOXY) BENZOATE ESTERS OF HYDROXYALKANOIC ACIDS AND DERIVATIVES THEREOF AS HERBICIDES

Abstract: Compounds of the formula wherein R₁ is selected from COOH; COOM where M is a cation selected from alkali metals, alkaline earth metals, ammonium, alkyl₁₋₅ and dialkyl₂₋₆ ammonium: and where R₄ and R₅ are selected from hydrogen and alkyl₁₋₅; R₂ and R₃ may be the same or different and each is selected from hydrogen; alkyl₁₋₅; QCOOR₆ where Q is alkyl₀₋₃, R₆ is alkyl1-5, hydrogen, a cation selected from alkali metals, alkaline earth metals, ammonium, alkyl₁₋₅ and dialkyl₂₋₆ ammonium; and and where R₁ may additionally be COOR₂, R₂ being alkyl₁₋₅ when (i) R₂ and R₃ are both alkyl or (ii) when at least one of R₂ and R₃ is selected from QCOOR₆ and have pre and post emergence herbicidal activity.

Description: 2-NITRO-5-tSU8STITUTED-PHENOXY) BENZOATE ESTERS OF HYDROXYALKANOIC AGIOS ANO DERIVATIVES THEREOF AS HERBICIDES This invention is concerned with certain herbicidal 2-nitro-5-(substituted-phenoxy) benzonate esters of hydroxy-alkanoic acids and derivatives thereof. Applicant Theissen herein has been granted a series of patents relating to 2-nitro-5-(substitutedphenoxy) benzoic acid derivatives including the salt, alkyl and cycloalkyl esters. U.S. Patent Nos. 3,652,645; 3,784,635; 3,873,302; 3,983,168 and 3,907,866 describe certain phenoxy benzoic acid derivatives which are useful as herbicides. We have now discovered further phenoxy benzoic acid derivatives which have good activity as herbicides. This invention relates to certain herbicidal compound within the class of 2-nitro-5-(substitutedphenoxy) benzoate esters of hydroxy alkanoic acids and derivatives thereof wherein there are up to six carbon atoms in the alkanoic acid moiety. Preferred members of this class are the a-hydroxy aikancia acids and derivatives which fall within the general formula: wherein EMI1.1 X1 is halogen, X2 is selected from halogen and hydrogen, and Z is a halogen-containing group such as a polyhalo1-9 a1ky114 group such as CF3, CHF2, C4F9, CF2CH2CH3 and CH2Cl. R1 is selected from COOH; COOM where M is a cation selected from alkali mettais, alkaline earth metals, ammoniumm alkyl1-5 and dialkyl2-6 ammonium; EMI2.1 where R4 and R5 are selected from hydrogen and alkyl1-5. R2 and Ra may be the same or different and each is selected from hydrogen; alkyl1-5; and QCOOR6 where Q is alkyl0-3, R6 is alkyl1-5, hydrogen, a cation selected from alkali metals, alkaline earth metals, ammonium, and alkyl1-5 and dialkyl1-5 ammonium or EMI2.2 R1 may additionally be COOR7 where R7 is alkyl1-5 when (i) R2 and R3 are both alkyl or (i) .when at least one of R2 and R3 is selected from QCOOR6 and EMI2.3 The term "alkyl" means straight or branched carbon chains where the carbon length is in the range set forth in the adjacent subscript. The specific 2-nitro-5-(substituted-phenoxy) benzoate ester compounds are described below. One method for preparing these compounds is the use of the Ullman ether synthesis reaction between the alkali metal (e.g., Na, K) salt of a suitable substituted phenol, e.g., m-hydroxy benzoic acid or m-cresol with an active halogen-substituted aromatic, e.g., 3,4-dicnlorobenzotrifluoride. The intermediate obtained may be nitrated and subsequently derivatized. Where m-cresol is used as a starting material, the produit obtained can be oxidized and subsequently nitrate before the derivatization. The derivatization steps may be carried out by known techniques. One such technique is the reaction of the appropriate halo-alkanoic acid or derivative with the salt of the particular 2-nitro-5(substituted phenoxy) benzoic acid. Another technique is the reaction of the desîred hydroxy alkanoic acid or derivative with the particular 2-nitro-5(substituted pnenoxy, ben#### ######. The following Examples are given by way of illustration. Compound 1 EMI3.1 Preparation of (2-propylaminocarbonyl) methyl 5-[2-chioro-4-(trifluoromethyl) phenoxyj-2-nitrobenzoate. To a solution of 5-[2-chloro-4-(trifluoromethyl) phenoxy)-2-nitrobenzoic acid (3.62 g., 0.01 mole) in methanol (25 mi) was added potassium t-butoxide (1.12 g., 0.01 mole). The solution was stirred for 0.5 hours as a solid formed. The solvent was stripped on a rotary evaporator. The resulting solid was then dissolved in dimethylacetamide (25 ml) and N-isopropyl a-chloro acetamide (1.36 g., 0.01 mole) was added. The stirred solution was heated to about 800C for 15 hours, cooled and poured into water (75 ml). A yellow solid formed and was filtered, washed and dried to give 4.17 g., m.p. 100-102 C. I.R. (nujol): C=O 1733 and 1665 cm-1 NMR (CDCi3): Doublet 1.18 ppm (J=4.0HZ, 6H) Multiplet 4.20 ppm (1H) Singlet 4.80 ppm (2H) Broad doublet 6;50 ppm (1H) Complex multiplet 7.1 - 8.0 ppm (6H) Doublet 8.20 ppm (J 0 4.1HZ, 1H) Compound 2 EMI4.1 Preparation of carboxymethyl 5-±2-chloro-4- (trifluoromethyl) phenoxy)-2-nitrobenzoate. To a stirred solution of 5-(2-chloro-4- (trifluoromethyl) phenoxy]-2-nitrobenzoyl chloride (19.0 g., 0.05 mole) in ether (50 ml) was added triethylamine (5.05 g., 0.05 mole) followed by the dropwise addition of a solution of glycolic acid (3.8 g., 0.05 mole) in ether (175 m1). There was an immediate heavy precipitate as the temperature rose to about 350C. The stirred solution was maintained at reflux for 22 hours, cooled and the precipitate of triethylamine hydrochloride filtered and dried to give 7.3 g., m.p. 235 2420. The ether solution was washed with saturated sodium chloride solution and then extracted twice with sodium carbonate solution. The acidified (HC1) basic solution gave 20.5 g of a tacky oil, which was dissolved in a 50:40 mixture of boiling heptane-benzene. The initial precipitate yielded some white solid corres- ponding to the acid of the tartina material. The second fraction consisted of a thick brown oii which slowly solidified givine 16.0 g. of a hard solid cake. The solid was broken up and triturated with hexane- ether. The resulting fluffy off-white solid was filtred and dried to aive 6.0 a.. m.p. 177-179 C. I.R. (nujol mull): C=O (broad)1610 and 1585 cm-1 NMR (D6MSO) : Broad Singlet 6.15 ppm (2H) Complex multiplet 7.0 - 8.2 ppm (7H) Compound 3 EMI5.1 Preparation of carboxymethyl 5-[2-chloro-4- (trifluoromethyl) phenoxy]-2-nitrobenzoate sodium salt. A -A solution of carboxymethyl 5-[2-chloro-4- (trifluoromethyl) phenoxy]-2-nitrobenzoate (2.1 g., 0.005 mole) and sodium methoxide (0.27 g., 0.005 mole) in absolute methanol was heated for 3 minutes at 500C. The solvent was removed on a rotary evaporator and the solid dried in a vacuum oven at 90-100 C for 2 hours giving a solid m.p. l80-l900C. I.R. (nujol): C=0 very broad 1600-1650 cm-1 Other illustrative &alpha;-hydroxy alkanoic acids and derivatives of the present invention are listed in Table I in accordance with the following formula: EMI6.1 TABLE I R1 R2 R3 COOC2H5 H COOC2H5 COOH CH2COOH CH2COOH CONHCH3 H H CON(C2H5)2 H H COOC4H9 CH3 CH3 COONH2(CH3)2 CH3 CH3 COOH CH3 CH3 CON(C3H7)2 H C2H5 COOH H C3H7 CONHC2H5 CH3 CH3 COOCH3 C4H9 C4H9 COOCH3 H (CH2)3COOCH3 COONa H CH2COONa COOC2H5 C2H5 CH3 CONH2 H CONH2 COOH H COOH COOH COOH CH3 Alkanoic acids and derivatives of the present invention also include those other than the a-hydroxy type described hereinabove. Such compounds would include unsaturated alkanoic acids and derivatives, e.g., where Q is an alkenyl of.two to six carbons. Other alkanoic acids and derivatives of the present invention include compound of Formula I wherein R1 is a carboxyalkyl group or derivative thereof such as where R1 is QCOOR6, Q being an alkyl of one to three carbons. The compound of this invention can be applied. in various ways to achieve herbicidal action. They can be applied per se, as solids or in vaporîzed form, but are preferably applied as the toxic components in pesticidal compositions of the compound and a carrier. These compositions are preferably applied directly to the soil and often incorporated therewith. The compositions can be applied as granulars or dusts; as liquid sprays, or as gas-propelled sprays and can contain, in addition to a carrier, additives such as emulsifying agents, binding agents, gases compressed to the liquid state, odorants, stabilizers, and the like. A wide variety of liquid and solid carriers can be used. Non-limiting examples of solid carriers include talc, bentonite, diatomaceous earth, pyrophyllite, fullers earth, gypsum, flours derived from cotton seeds and nut shells, and various natural and synthetic clays having a pH not exceeding about 9.5. Non-limiting examples of liquid carriers include water, organic solvents such as alcohols, ketones, light oils, and medium oils and vegetable oils such as cottonseed oil. In practice, herbicidal application is measured in terms of pounds of herbicide applied per acre. The compounds of this invention are effective herbicides when applied in herbicidal amounts, e.g., at rates between about 0.2 and 10 kg. per hectare. The pesticidal compositions comprising the active ingredient and the carrier may be suppliez either as ready-to use compositions or as concentrates. Concentrates generaliy contain a higher proportion of the active ingredient than the ready-to-use compositions and accordingly, require dilution prior to use. Both the ready-to-use compositions and the concentrates may be in liquid or solid form, i.e., with the active ingredient blended with a liquid or solid carrier, respectively. The amount of active ingredient in the composition will depend, primarily, upon whether the composition is a concentrate or a ready-to-use composition. Concentrates will generally contain from 5 to 95% by weight, preferably 10 to 80% by weight, of the active ingredient, The concentration of active ingredient in the ready-to-use compositions will vary according to the method of application for the compo sition in question and to the desired application rate. In general, ready-to-use compositions will contain from 0.001 to 1, preferably 0.01 to 0.1 percent by weight of the active ingredient. Thus, the compositions may contain from 0.001 to 95% by weight of active ingredient, the actual amount depending upon the nature of the composition and the method by which it shall be applied. Concentrates may be either liquid or solid and are usually extendable with water to form emulsions or suspensions containing a smaller proportion of the active ingredient. Alternatively, liquid or solid concentrates may be extended with liquid or solid carriers to give the final ready-to-use composition. Liquid concentrates preferably comprise the active ingredient and an emulsifying agent dissolved in a liquid solvent, e.g., an organic solvent of the type mentioned above. The emulsifier is suitably an anionic, cationic or non-ionic emulsifier, e.g., sodium dodecylbenzensulfonate or an ethylene oxide derivative of an alkyl pheonol, a mercaptan, an amine or a rboxylic acid liquid concentrates may contain from 10 to 30 weight percent, e.g., 25 weight percent of the active ingredient, e.g., 1 kg. of active ingredient per 4 kg. of concentrate. Wettable powders are another preferred form of concentrate and these suitably comprise the active ingredient, a finely-divided solid carrier and at least one surfactant to impart wettability or dispersability. Solid carriers which are suitable for preparing wettable powder formulations may be either organic or inorganic in nature. Suitable organic carriers are soybean, walnut, or wood flour or tobacco dust, and suitable inorganic ones are clays of the bentonite, kaolinite, or fuller's earth types; silicas such as diatomaceous earth; silicates such as talc, pyrophyllite, or alcaline earth silicates; and calcium and magnesium carbonates. The carrier may be a single substance or a mixture of finely divided solids. A surfactant or mixture of surfactants is generally present in an amount of 1 to 10 percent by weight of the wettable powder formulation. Suitable dispersing agents are sodium formaldehydenapthalene sulfonate or sodium lignin sulfonate. Wetting agents include higher alkylaryl sulfonates ("higher alkyl" meaning alkyl of at least 8 carbon atoms) such as calcium dodecylbenzenesulfonate, alcohol sulfates, alkylphenoxyethoxyethoxyethyl sodium sulfonates, sodium dioctyl sulfosuccinate, and ethylene oxide adducts with fattytalcohols, fatty acids, or with higher alkyl-phenols, such as octylphenoxypolyethoxyethanol. Sticking or spreading agents may be included such as glycerol mannitan laurate or a condensate of polyglycerol and oleic acid modified with phthalic anhydride. The active ingredient content of the wettable powder may be in the range of 20 to 80S by weight; however, the preferred range of concentrations is 30% to 80% Dusts may be made by incorporating the active ingredient into a solid carrier, such as finely powdered clays, talc, silica, and synthetic silicates, alkaline earth carbonates, and diluents of natural origin such as tobacco dust or walnut shell flour. Canular formulations can be made from similar type solid carriers except that the particle size is larger in the range of 15 to 60 mesh (U.S. Standard Sieve Series). A small amount of dispersing agent may be incorporated in these solid formulations. The concentration of active ingredients in these dust or granular formulations may be in the range of 1 to 20% by weight. The solid carriers used in these formulations may be essentially inert or they may consist wholly or in part of fertilizing materials such as ammonium sulfate, or other ammonium salts, urea, calcium phosphates, potassium chloride or dried blood. One particularly convenient method for making solid formulations is to treat the solid carrier with the active ingredients dissolved in a solvent and allow the solvent to evaporate off. This results in the carrier which is usually in the form of finely divided particles, being impregnated with the active ingredients. Another method is to apply the mixture of active ingredients in the molten state or by spraying. The concentration of the active ingredient in the final ready-to-use composition will depend not only upon the application rate desired (generally in the range of 0.2 to 10 kg. per hectare, as mentioned above), but also upon the application method which is to b used. Wettable powders and liquid concentrates are usually applied as aqueous sprays and applied at application rates varying from about 10 to 1500 liters per hectare. With ground equipment, the application rate will generally be in the range of 100 to 500 liters per hectare, whereas aerial spray equipment will generally apply 15 to 80 liters per hectare. Herbicidal Effectiveness Method of Propaqating Test Species Crop and weed species are planted in 8" x 10" disposable fiber flats containing potting soil to provide each flat with a 4" row of all test species. Crop species consist of field corn (CN), crabgrass (CG), cotton (CT), and soybeans (SB). The weed species consist of foxtail millet (FM), green foxtail (GF), veîvetleaf (VL), cocklebur (Ce), wild mustard (WM) and pigweed (PW). Cotton, corn, soybean, and cocklebur plantings consist of 4 to 5 seeds per row depending upon species. The smaller seeded species (velvetleaf, wild mustard, pigweed, foxtail millet and green foxtail) are planted in an uncounted but sufficient number to provide a solid row of seedlings. Plantings for the preand post-emergence portions of the test are identical as to seeding. The initial watering until emergence is done from the top. The post-emergence phase is propagated in advance so as to provide plants of the proper stage of development atthe time of treatment. Plantings for the pre-emergence phase are made not more than one day in advance of treatment. The desired stage of development for treatment of the post-emergence broadleaf species (CT, SB, CE, VL, WM, PW) is the one true leaf or first trifoliate leaf stage. The desired stage for corn would be a height of 3-4, while a 2 ###### would be grasses. Method of Treatment Spray applications are made with a handgun sprayer (aspirator type) simultaneously to one flat of established plants for the post-emergence phase and one newly seeded flat for the pre-emergence phase. The 10 lb./acre treatment rate consists of the uniform application of 116 milligrams of test compound to the combined area of the two flats (160 sq. inches). Application is made in a solvent mixture consisting of 40 ml acetone and 40 ml water and a surfactant concentration of 0.1%. Following spray application, flats are returned to the greenhouse where watering of the post-emergence phase is done only by subirrigation. The pre-emergence phase is top watered by sprinkling until after test species have emerged. Subsequent watering is by subirrigation. Two weeks after treatment, the pre- and postemergence injury and control is rated on a 0-100S injury and control scale. Special physiological effects are rated as to intensity also at this time. The herbicidal test data reported for compounds 1-3 was obtained at application rates of 10 lbs. down to 1/4 lb./acre. The following lists the metric equivalents for each rate. Application Rate US - lb./acre Metric - kg/ha 10.0 11.2 4.0 4.48 2.0 2.24 1.0 1.12 0.5 0.56 0.25 0.28 Test results are set forth in Table II(preemergence) and Table III (post-emergence). TABLE II Cpd. Dosage Post-Emergence No. Lbs./ Acre CG FM GF VL CB WM PW CT CN SB 1 2 - 90 90 20 60 100 100 10 0 1/2 - 90 90 10 30 90 100 20 10 0 1/4 - 60 30 10 0 90 90 0 0 0 2 10 - 100 100 100 50 100 60 70 80 0 4 - 100 100 90 20 100 100 30 40 0 2 - 100 90 90 20 100 100 40 10 0 1 - 90 90 80 0 100 100 0 0 0 1/2 - 90 90 50 0 100 90 0 0 0 1/4 - 0 10 20 0 80 90 10 10 0 3 10 - 100 100 100 100 100 0 90 90 0 4 - 100 100 100 90 100 100 40 70 0 2 - 100 100 90 90 100 100 20 60 0 1 - 100 100 60 30 100 100 10 40 0 1/2 - 90 90 20 0 100 90 10 0 0 1/4 - 70 60 70 10 100 20 0 10 0 TABLE III Cpd. Dosage Post-Emergence No. Lbs./ Acre CG FM GF VL CB WM PW CT CN SB 1 2 - 90 90 100 100 100 100 90 90 10 1/2 - 90 90 100 90 100 100 100 40 20 1/4 - 90 90 90 60 90 90 90 40 50 2 10 - 100 100 100 100 100 100 100 100 70 4 - 100 100 100 100 100 100 100 100 50 2 - 100 100 100 100 100 100 100 90 40 1 - 100 100 100 100 100 100 90 90 40 1/2 - 90 90 90 90 100 100 90 70 50 1/4 - 50 80 70 100 100 100 80 30 50 3 10 - 100 100 100 100 100 100 100 100 60 4 - 100 100 100 100 100 100 100 100 40 2 - 100 100 100 100 100 100 100 100 50 1 - 100 100 100 100 100 100 90 80 60 1/2 - 90 90 100 90 100 100 90 70 30 1/4 - 70 80 70 90 100 100 80 20 30

Claims: WHAT IS CLAIMED IS: 1. Herbicidal compounds of the formula EMI17.1 wherein R1 is selected from COOH; COOM where M is a cation selected from alkali metals, alkaline earth metals, ammonium, alkyl1-5 and dialkyl2-6 ammonium; EMI17.2 where R4 and R5 are selected from hydrogen and alkyl1-5; R2 and R3 may be the same or different and each is selected from hydrogen; alkyl1-5; QCOOR6 where Q is alkyl0-3, R6 is alkyl1-5, hydrogen, a cation selected from aikali metals, alkallne earth metals, ammonium, alkyl1-5 and dialkyl2-6 ammonium; EMI17.3 and where R1 may additionally be COOR7, R7 being alkyl1-5 when (i) R2 and R3 are both alkyl or (ii) when at least one of R2 and R3 is selected from QCOOR6 and EMI17.4 2. The compounds of Claim 2 wherein R2 and R3 are botn hydrogen. 3. The compounds of Claim 1 wherein R2 and R3 are both alkyl1-5. 4. The compound of Claim 3 wherein R1 is COOR7. 5. The compounds of Claim 3 wherein R2 and R3 are both ethyl 1-2 6. The compounds of Claim 1 wherein R2 is hydrogen and R3 is selected of the groups other than hydrogen. 7. The compounds of Claim 6 wherein R3 is QCOOR6. 8. The compounds of Claim 7 wherein R1 is COOR7. 9. The compounds of Claim 7 wherein Q is alkyl1-3. 10. The compounds of Claim 7 wherein R6 is selected from said cations. 11. The compounds of Claim 7 wherein R6 is hydrogen. 12. The compounds of Claim 7 wherein R6 is alkyll¯5. 13. The compounds of Claim 7 wherein Ra is COOR6. 14. The compounds of Claim 7 wherein R1 is COOH. 15. The compound of Claim 6 wherein R2 is alkyl1-5. 16. The compound of Claim 6 wherein R3 is EMI19.1 17. The compounds of Claim 1 wherein R2 and R3 are QCOOR6. 18. The compound of Claim 17 wherein R1 is COOR7. 19. A herbicidal composition comprising an herbicidally effective amount of a compound of Claim 1 and a carrier therefor. 20. A method for combating undesirable herbs, said method comprising contacting them with an herbicidally effective amount of a compound defined in Claim 1. 21. A method of preparing a compound as defined in Claim 1, which comprises reacting a compound of the formula EMI19.2 where X1, X2, M and Z are as defined in Claim 1, with an alkanoic acid or halide thereof cf the formula XCRlR2RD where R1, R2 and R3 are as defined in Claim 1 and X is halogen. 22. A method of preparing a compound as defined in Claim 1, which comprises reacting a compound of the formula EMI20.1 where X1, X2 and Z are as defined in Claim 1 and Y Is halogen, with an alkanoic acid of the formula HOCR1R2R wnere R1, R2 and R3 are as defined in Claim 1.

Inventors: THEISSEN, ROBERT JAMES
Applicants: RHONE-POULENC AGROCHIMIE
Application year: 1981
Main classification: C07C79
IPC codes: C07C201, C07C67, C07C205, C07C231, A01N37, C07C235