WO2024099889A1 - Weed control method - Google Patents

Abstract

A compound of Formula I Formula (I) wherein: R1, R2, R3, R4 and R5 are independently selected from the group consisting of hydrogen, halogen, amino, cyano, nitro, hydroxyl, C1-5alkyl, C3-6cycloalkyl, C1-2haloalkyl, cyanomethyl, C1-2alkoxyC1-2alkyl, C1-4alkoxy, C1-2haloalkoxy, C2-3alkenyl, C2-3alkynyl, halophenyl, C1- 2alkoxycarbonyl, C1-2alkylsulfanyl, C1-2alkylsulphinyl and C1-2alkylsulfonyl; or R1 and R2 together with the carbon atoms to which they are attached form a 5- or 6-membered ring, which may optionally be substituted by one or more groups selected from halogen, cyano, hydroxyl, C1-5alkyl, C1-2haloalkyl, and C1-4alkoxy, and wherein the 6-membered ring contains zero, one or two nitrogen atoms and wherein the 5-membered ring contains one or two heteroatoms independently selected from the group consisting of nitrogen and oxygen; R6 is selected from the group consisting of hydrogen, C1-6alkyl and arylC1-2alkyl, and wherein at least one of R1 to R5 is hydrogen and at least one of R1 to R5 is not hydrogen, or an agronomically acceptable salt of said compound.

Description

WEED CONTROL METHOD

The present invention relates to the use of certain compounds as herbicides, to herbicidal compositions which comprise the compounds, and to their use for controlling weeds, in particular in crops of useful plants, or for inhibiting plant growth.

The present invention is based on the finding that certain chlorofluoro phenylacetic acids of formula (I) as defined herein, exhibit surprisingly good herbicidal activity. Thus, according to the present invention there is provided a compound of Formula (I),

wherein:

R¹, R², R³, R⁴ and R⁵ are independently selected from the group consisting of hydrogen, halogen, amino, cyano, nitro, hydroxyl, Ci-salkyl, Cs-ecycloalkyl, Ci-2haloalkyl, cyanomethyl, Ci-2alkoxyCi-2alkyl, Ci-4alkoxy, Ci-2haloalkoxy, C2-3alkenyl, C2-3alkynyl, halophenyl, Ci- 2alkoxycarbonyl, Ci-2alkylsulfanyl, Ci-2alkylsulphinyl and Ci-2alkylsulfonyl; or

R¹ and R² together with the carbon atoms to which they are attached form a 5- or 6-membered ring, which may optionally be substituted by one or more groups selected from halogen, cyano, hydroxyl, Ci-salkyl, Ci-2haloalkyl, and Ci-4alkoxy, and wherein the 6-membered ring contains zero, one or two nitrogen atoms and wherein the 5-membered ring contains one or two heteroatoms independently selected from the group consisting of nitrogen and oxygen;

R⁶ is selected from the group consisting of hydrogen, Ci-ealkyl and arylCi-2alkyl; and wherein at least one of R¹ to R⁵ is hydrogen and at least one of R¹ to R⁵ is not hydrogen, or an agronomically acceptable salt of said compound. According to a second aspect of the invention, there is provided the use of a compound of Formula I as a herbicide.

According to a third aspect of the invention, there is provided an agrochemical composition comprising a herbicidally effective amount of a compound of formula (I) and an agrochemically-acceptable diluent or carrier. Such an agricultural composition may further comprise at least one additional active ingredient.

According to a fourth aspect of the invention, there is provided a method of controlling or preventing undesirable plant growth, wherein a herbicidally effective amount of a compound of formula (I), or a composition comprising this compound as active ingredient, is applied to the plants, to parts thereof or the locus thereof.

As used herein, the term "halogen" or “halo” refers to fluorine (fluoro), chlorine (chloro), bromine (bromo) or iodine (iodo), preferably fluorine, chlorine or bromine.

As used herein, cyano means a -CN group.

As used herein, hydroxy or hydroxyl means an -OH group.

As used herein, nitro means an -NO2 group.

As used herein, amino means an -NH2 group.

As used herein, the term "C1-C5 alkyl" refers to a straight or branched hydrocarbon chain radical consisting solely of carbon and hydrogen atoms, containing no unsaturation, having from one to five carbon atoms, and which is attached to the rest of the molecule by a single bond. Ci-Csalkyl and Ci-C2alkyl are to be construed accordingly. Examples of Ci-Csalkyl include, but are not limited to, methyl (Me), ethyl (Et), n-propyl, 1-methylethyl (iso-propyl), n- butyl, and 1 -dimethylethyl (f-butyl).

As used herein, the term "C3-8 cycloalkyl" refers to a stable, monocyclic ring radical which is saturated and contains 3 to 8 carbon atoms. Cs-ecycloalkyl is to be construed accordingly. Examples of Cs-scycloalkyl include, but are not limited to, cyclopropyl, cyclobutyl, cyclopentyl and cyclohexyl. As used herein, the term "C1-C4 alkoxy" refers to a radical of the formula -OR_a where R_a is a Ci-C4alkyl radical as generally defined above. C1-C2 alkoxy is to be construed accordingly. Examples of Ci-4alkoxy include, but are not limited to, methoxy, ethoxy, propoxy, iso-propoxy and f-butoxy.

As used herein, the term "C1-2 alkoxyCi-2alkyl" refers to a radical of the formula Rb-O-Ra- wherein Rb is a Ci-2alkyl radical as generally defined above, and Ra is a Ci-2alkylene radical as generally defined above.

As used herein, the term "C1-C2 haloalkyl" refers to a Ci-C2alkyl radical as generally defined above substituted by one or more of the same or different halogen atoms. C2haloalkyl is to be construed accordingly. Examples of Ci-C2haloalkyl include, but are not limited to chloromethyl, fluoromethyl, fluoroethyl, difluoromethyl, trifluoromethyl and 2,2,2-trifluoroethyl.

As used herein, the term "C2-C3 alkenyl" refers to a straight or branched hydrocarbon chain radical group consisting solely of carbon and hydrogen atoms, containing at least one double bond that can be of either the (E)- or (^-configuration, having from two to three carbon atoms, which is attached to the rest of the molecule by a single bond. Examples of C2-C3alkenyl include, but are not limited to ethenyl, prop-1 -enyl and allyl (prop-2-enyl).

As used herein, the term "C2-C3 alkynyl" refers to a straight or branched hydrocarbon chain radical group consisting solely of carbon and hydrogen atoms, containing at least one triple bond, having from two to three carbon atoms, and which is attached to the rest of the molecule by a single bond. Examples of C2-C3alkynyl include, but are not limited to ethynyl, prop-1 -ynyl and propargyl (prop-2-ynyl).

As used herein, the term "C1-C2 haloalkoxy" refers to a Ci-C2alkoxy group as defined above substituted by one or more of the same or different halogen atoms. Examples of C1- C2haloalkoxy include, but are not limited to fluoromethoxy, difluoromethoxy, fluoroethoxy, trifluoromethoxy and trifluoroethoxy.

As used herein, the term “C1-2 alkylsulfanyl” refers to a radical of the formula - SR_a wherein R_a is a Ci-2alkyl radical as generally defined above.

As used herein, the term “C1-2 alkylsulfinyl” refers to a radical of the formula -

S(O)R_a wherein R_a is a Ci-2alkyl radical as generally defined above. As used herein, the term “C1-2 alkylsulfonyl” refers to a radical of the formula - S(0)2R_a wherein R_a is a Ci-2alkyl radical as generally defined above.

As used herein, the term “Ci-2alkoxycarbonyl” refers to a radical of the formula RaOC(O)-, wherein Ra is a Ci-2alkyl radical as generally defined above.

As used herein, the term “Ci-3alkoxycarbonylCi-3alkyl” refers to a radical of the formula - RbC(O)OR_a, wherein R_a is a C1-3 alkyl radical as generally defined above and Rb is a Cisalkylene radical as generally defined above.

As used herein, the term "arylCi-2alkyl" refers to a aryl ring as defined above which is attached to the rest of the molecule by a Ci-2alkylene radical as defined above.

As used herein, the term “cyanoCi-ealkyl” refers to a Ci-ealkyl radical as generally defined above substituted by one or more cyano groups. CyanoCi-4alkyl is to be construed accordingly. Examples of cyanoCi-ealkyl include, but are not limited to, cyanomethyl.

The presence of one or more possible asymmetric carbon atoms in a compound of formula (I) means that the compounds may occur in chiral isomeric forms, i.e., enantiomeric or diastereomeric forms. Also atropisomers may occur as a result of restricted rotation about a single bond. Formula (I) is intended to include all those possible isomeric forms and mixtures thereof. The present invention includes all those possible isomeric forms and mixtures thereof for a compound of formula (I). Likewise, formula (I) is intended to include all possible tautomers (including lactam-lactim tautomerism and keto-enol tautomerism) where present. The present invention includes all possible tautomeric forms for a compound of formula (I). Similarly, where there are di-substituted alkenes, these may be present in E or Z form or as mixtures of both in any proportion. The present invention includes all these possible isomeric forms and mixtures thereof for a compound of formula (I).

The compounds of formula (I) will typically be provided in the form of an agronomically acceptable salt, a zwitterion or an agronomically acceptable salt of a zwitterion. This invention covers all such agronomically acceptable salts, zwitterions and mixtures thereof in all proportions.

Suitable agronomically acceptable salts of the present invention can be with cations that include but are not limited to, metals, conjugate acids of amines and organic cations. Examples of suitable metals include aluminium, calcium, cesium, copper, lithium, magnesium, manganese, potassium, sodium, iron and zinc. Examples of suitable amines include allylamine, ammonia, amylamine, arginine, benethamine, benzathine, butenyl-2-amine, butylamine, butylethanolamine, cyclohexylamine, decylamine, diamylamine, dibutylamine, diethanolamine, diethylamine, diethylenetriamine, diheptylamine, dihexylamine, diisoamylamine, diisopropylamine, dimethylamine, dioctylamine, dipropanolamine, dipropargylamine, dipropylamine, dodecylamine, ethanolamine, ethylamine, ethylbutylamine, ethylenediamine, ethylheptylamine, ethyloctylamine, ethylpropanolamine, heptadecylamine, heptylamine, hexadecylamine, hexenyl-2-amine, hexylamine, hexylheptylamine, hexyloctylamine, histidine, indoline, isoamylamine, isobutanolamine, isobutylamine, isopropanolamine, isopropylamine, lysine, meglumine, methoxyethylamine, methylamine, methylbutylamine, methylethylamine, methylhexylamine, methylisopropylamine, methylnonylamine, methyloctadecylamine, methylpentadecylamine, morpholine, N,N- diethylethanolamine, N-methylpiperazine, nonylamine, octadecylamine, octylamine, oleylamine, pentadecylamine, pentenyl-2-amine, phenoxyethylamine, picoline, piperazine, piperidine, propanolamine, propylamine, propylenediamine, pyridine, pyrrolidine, secbutylamine, stearylamine, tallowamine, tetradecylamine, tributylamine, tridecylamine, trimethylamine, triheptylamine, trihexylamine, triisobutylamine, triisodecylamine, triisopropylamine, trimethylamine, tripentylamine, tripropylamine, tris(hydroxymethyl)aminomethane, and undecylamine. Examples of suitable organic cations include benzyltributylammonium, benzyltrimethylammonium, benzyltriphenylphosphonium, choline, tetrabutylammonium, tetrabutylphosphonium, tetraethylammonium, tetraethylphosphonium, tetramethylammonium, tetramethylphosphonium, tetrapropylammonium, tetrapropylphosphonium, tributylsulfonium, tributylsulfoxonium, triethylsulfonium, triethylsulfoxonium, trimethylsulfonium, trimethylsulfoxonium, tripropylsulfonium and tripropylsulfoxonium.

In a preferred embodiment, the agrochemically acceptable salt is selected from the group consisting of sodium, potassium, aluminium, dimethylamine (DMA), diglycolamine (DGA) and choline salt. In an especially preferred embodiment, the agrochemically acceptable salt is choline salt.

The following list provides definitions, including preferred definitions, for substituents R¹, R², R³, R⁴, R⁵ and R⁶ with reference to the compounds of formula (I) according to the invention. For any one of these substituents, any of the definitions given below may be combined with any definition of any other substituent given below or elsewhere in this document. Preferably R¹ is selected from the group consisting of hydrogen, halogen, amino, cyano, nitro, hydroxyl, Ci-4alkyl, C3-4cycloalkyl, Ci-2haloalkyl, Ci-4alkoxy, Ci-2haloalkoxy, C2-3alkenyl, C2- salkynyl, halophenyl and Ci-2alkylsulfanyl, more preferably hydrogen, fluorine, chlorine, bromine, amino, cyano, Ci-4alkyl, cyclopropyl, halomethyl, Ci-3alkoxy, Cihaloalkoxy, vinyl, ethynyl and methylsulfanyl, most preferably chlorine, bromine, cyano, methyl, ethyl, cyclopropyl, difluoromethyl, trifluoromethyl, methoxy, ethoxy, vinyl and ethynyl.

Preferably R² is selected from the group consisting of hydrogen, halogen, amino, cyano, nitro, hydroxyl, Ci-4alkyl, C3-4cycloalkyl, Ci-2haloalkyl, Ci-4alkoxy, Ci-2haloalkoxy, C2-3alkenyl, C2- salkynyl, halophenyl and Ci-2alkylsulfanyl, more preferably hydrogen, fluorine, chlorine, bromine, cyano, Ci-4alkyl, cyclopropyl, halomethyl, Ci-3alkoxy, Cihaloalkoxy, vinyl, ethynyl, fluorophenyl and methylsulfanyl, most preferably hydrogen, chlorine, bromine, cyano, methyl, cyclopropyl, difluoromethyl, trifluoromethyl, methoxy, vinyl and ethynyl.

Preferably R¹ and R² together with the carbon atoms to which they are attached form a 5- membered ring containing one or two heteroatoms independently selected from the group consisting of nitrogen and oxygen, more preferably the 5-membered ring contains two oxygen atoms. Preferably the 5-membered ring is partially saturated, most preferably the 5-membered ring is saturated. Preferably the 5-membered ring is substituted by one or two substituents independently selected from the group consisting of fluorine, chlorine and methyl, more preferably the 5-membered ring is substituted by two fluorine.

Preferably R¹ and R² together with the carbon atoms to which they are attached form a 6- membered ring containing zero, one or two nitrogen atoms, more preferably the 6-membered ring contains zero or one nitrogen, with the proviso that any nitrogen in the 6-membered ring is next to the benzene ring in structure (I). Preferably the 6-membered ring is aromatic.

Preferably the 6-membered ring is substituted by zero or one substituent. If substituted, the substituent is preferably chlorine.

Preferably R³ is selected from the group consisting of hydrogen, halogen, amino, cyano, hydroxyl, Ci-Csalkyl, Ci-2haloalkyl, Ci-C4alkoxy, C2-C3alkenyl, C2-C3alkynyl, Ci-C2haloalkoxy and halophenyl, more preferably hydrogen, halogen, amino, trifluoromethoxy, trifluoromethyl, methyl, tert-butyl and methoxy, most preferably hydrogen, fluorine and chlorine.

Preferably R⁴ is selected from the group consisting of hydrogen, amino, fluorine, chlorine, methoxy, more preferably hydrogen. Preferably R⁵ is selected from the group consisting of hydrogen, fluorine, chlorine, amino, nitro and methoxy, more preferably hydrogen, chlorine and methoxy.

Preferably R⁶ is selected from the group consisting of hydrogen, Ci-Csalkyl and benzyl, more preferably hydrogen.

Preferably, if only one of R¹ to R⁵ is hydrogen then R³ is hydrogen.

Preferably, R¹ is not methyl when each of R² to R⁵ is hydrogen; R² is not methyl when each of R¹ and R³ to R⁵ is hydrogen; and R³ is not F or NChwhen each of R¹, R², R³ and R⁴ is hydrogen.

Advantageously, there is provided the use of a compound of Formula I as a herbicide, wherein R¹ is methyl and each of R² to R⁵ is hydrogen; R² is methyl and each of R¹ and R³ to R⁵ is hydrogen; and R³ is F or NO2 and each of R¹, R², R³ and R⁴ is hydrogen.

Table of Examples

Table 1 below discloses 818 specific compounds of formula (I), designated compound numbers 1-1 to 1-818 respectively, wherein R⁶ is hydrogen.

Table 1

818 compounds of formula (I), wherein R⁶ is methyl and the values of R¹-R⁵ are as given in Table 1 for compounds 1-1 to 1-818, are designated as compound numbers 2-1 to 2-818 respectively. 818 compounds of formula (I), wherein R⁶is ethyl and the values of R¹-R⁵ are as given in Table 1 for compounds 1-1 to 1-818, are designated as compound numbers 3-1 to 3-818 respectively.

818 compounds of formula (I), wherein R⁶ is benzyl and the values of R¹-R⁵ are as given in Table 1 for compounds 1-1 to 1-818, are designated as compound numbers 4-1 to 4-818 respectively.

818 compounds of formula (I), wherein R⁶ is lithium and the values of R¹-R⁵ are as given in Table 1 for compounds 1-1 to 1-818, are designated as compound numbers 5-1 to 5-818 respectively.

818 compounds of formula (I), wherein R⁶ is sodium and the values of R¹-R⁵ are as given in Table 1 for compounds 1-1 to 1-818, are designated as compound numbers 6-1 to 6-818 respectively.

818 compounds of formula (I), wherein R⁶ is ammonium and the values of R¹-R⁵ are as given in Table 1 for compounds 1-1 to 1-818, are designated as compound numbers 7-1 to 7-818 respectively.

818 compounds of formula (I), wherein R⁶ is diisopropylammonium and the values of R¹-R⁵ are as given in Table 1 for compounds 1-1 to 1-818, are designated as compound numbers 8-1 to 8-818 respectively.

818 compounds of formula (I), wherein R⁶ is N,N,N-trimethylethanolammonium and the values of R¹-R⁵ are as given in Table 1 for compounds 1-1 to 1-818, are designated as compound numbers 9-1 to 9-818 respectively.

Compounds of formula (I) may be prepared from esters of formula (A) as shown in reaction scheme 1.

Reaction scheme 1

(A) (I)

For example, a compound of formula (A), wherein R6 represents methyl or ethyl, may be treated with a base, such as lithium hydroxide, in a suitable solvent such as a mixture of methanol and water.

Compounds of formula (A) may be prepared from compounds of formula (B) as shown in reaction scheme 2.

Reaction scheme 2

(B) (A)

For example, a mixture of a compound of formula (B), wherein R6 represents methyl or ethyl, in a suitable solvent such as tetra hydrofuran, may be treated with a base such as sodium bis(trimethylsilyl)amide, followed by a chlorinating reagent such as /V-chlorosuccinimide.

Compounds of formula (B) may be prepared from aryl halides of formula (C) as shown in reaction scheme 3.

Reaction scheme 3

(C) (D) (B)

For example, a mixture of a compound of formula (C), wherein X represents iodo or bromo, and a compound of formula (D), wherein R6 represents methyl or ethyl, may be treated with a catalyst such as nickel(ll) iodide, a ligand such as 5,5’-dimethyl-2,2’-bipyridine, a metal such as zinc and a metallic species such as dichloromagnesium in a suitable solvent such as /V,/V- dimethylacetamide.

Aryl halides of formula (C) are commercially available or may be prepared by methods well known in the literature.

Compounds of formula (D) are commercially available or may be prepared by methods well known in the literature.

Compounds of formula (B) may also be prepared from aryl acetic esters of formula (E) as shown in reaction scheme 4.

Reaction scheme 4

For example, a compound of formula (E), wherein R6 represents methyl or ethyl, may be treated with a base such as sodium bis(trimethylsilyl)amide, followed by a fluorinating reagent such as /V-fluorobenzenesulfonimide, in a suitable solvent such as tetrahydrofuran.

Aryl acetic esters of formula (E) are commercially available or may be prepared by methods well known in the literature. Compounds of formula (B) may also be prepared from compounds of formula (F) as shown in reaction scheme 5.

Reaction scheme 5

For example, a compound of formula (F), wherein R6 represents methyl or ethyl, may be treated with a fluorinating reagent such as diethylaminosulfur trifluoride, in a suitable solvent such as dichloromethane.

Compounds of formula (F) are commercially available or may be prepared by methods well known in the literature.

The compounds according to the invention can be used as herbicidal agents in unmodified form, but they are generally formulated into compositions in various ways using formulation adjuvants, such as carriers, solvents and surface-active substances. The formulations can be in various physical forms, e.g. in the form of dusting powders, gels, wettable powders, water- dispersible granules, water-dispersible tablets, effervescent pellets, emulsifiable concentrates, microemulsifiable concentrates, oil-in-water emulsions, oil-flowables, aqueous dispersions, oily dispersions, suspo-emulsions, capsule suspensions, emulsifiable granules, soluble liquids, water-soluble concentrates (with water or a water-miscible organic solvent as carrier), impregnated polymer films or in other forms known e.g. from the Manual on Development and Use of FAO and WHO Specifications for Pesticides, United Nations, First Edition, Second Revision (2010). For water-soluble compounds, soluble liquids, water-soluble concentrates or water soluble granules are preferred. Such formulations can either be used directly or diluted prior to use. The dilutions can be made, for example, with water, liquid fertilisers, micronutrients, biological organisms, oil or solvents.

The formulations can be prepared e.g. by mixing the active ingredient with the formulation adjuvants in order to obtain compositions in the form of finely divided solids, granules, solutions, dispersions or emulsions. The active ingredients can also be formulated with other adjuvants, such as finely divided solids, mineral oils, oils of vegetable or animal origin, modified oils of vegetable or animal origin, organic solvents, water, surface-active substances or combinations thereof.

The active ingredients can also be contained in very fine microcapsules. Microcapsules contain the active ingredients in a porous carrier. This enables the active ingredients to be released into the environment in controlled amounts (e.g. slow-release). Microcapsules usually have a diameter of from 0.1 to 500 microns. They contain active ingredients in an amount of about from 25 to 95 % by weight of the capsule weight. The active ingredients can be in the form of a monolithic solid, in the form of fine particles in solid or liquid dispersion or in the form of a suitable solution. The encapsulating membranes can comprise, for example, natural or synthetic rubbers, cellulose, styrene/butadiene copolymers, polyacrylonitrile, polyacrylate, polyesters, polyamides, polyureas, polyurethane or chemically modified polymers and starch xanthates or other polymers that are known to the person skilled in the art. Alternatively, very fine microcapsules can be formed in which the active ingredient is contained in the form of finely divided particles in a solid matrix of base substance, but the microcapsules are not themselves encapsulated.

The formulation adjuvants that are suitable for the preparation of the compositions according to the invention are known perse. As liquid carriers there may be used: water, toluene, xylene, petroleum ether, vegetable oils, acetone, methyl ethyl ketone, cyclohexanone, acid anhydrides, acetonitrile, acetophenone, amyl acetate, 2-butanone, butylene carbonate, chlorobenzene, cyclohexane, cyclohexanol, alkyl esters of acetic acid, diacetone alcohol, 1 ,2- dichloropropane, diethanolamine, p-diethylbenzene, diethylene glycol, diethylene glycol abietate, diethylene glycol butyl ether, diethylene glycol ethyl ether, diethylene glycol methyl ether, /V,/V-dimethylformamide, dimethyl sulfoxide, 1 ,4-dioxane, dipropylene glycol, dipropylene glycol methyl ether, dipropylene glycol dibenzoate, diproxitol, alkylpyrrolidone, ethyl acetate, 2-ethylhexanol, ethylene carbonate, 1 ,1 ,1 -trichloroethane, 2-heptanone, alphapinene, d-limonene, ethyl lactate, ethylene glycol, ethylene glycol butyl ether, ethylene glycol methyl ether, gamma-butyrolactone, glycerol, glycerol acetate, glycerol diacetate, glycerol triacetate, hexadecane, hexylene glycol, isoamyl acetate, isobornyl acetate, isooctane, isophorone, isopropylbenzene, isopropyl myristate, lactic acid, laurylamine, mesityl oxide, methoxypropanol, methyl isoamyl ketone, methyl isobutyl ketone, methyl laurate, methyl octanoate, methyl oleate, methylene chloride, m-xylene, n-hexane, n-octylamine, octadecanoic acid, octylamine acetate, oleic acid, oleylamine, o-xylene, phenol, polyethylene glycol, propionic acid, propyl lactate, propylene carbonate, propylene glycol, propylene glycol methyl ether, p-xylene, toluene, triethyl phosphate, triethylene glycol, xylenesulfonic acid, paraffin, mineral oil, trichloroethylene, perchloroethylene, ethyl acetate, amyl acetate, butyl acetate, propylene glycol methyl ether, diethylene glycol methyl ether, methanol, ethanol, isopropanol, and alcohols of higher molecular weight, such as amyl alcohol, tetrahydrofurfuryl alcohol, hexanol, octanol, ethylene glycol, propylene glycol, glycerol, /V-methyl-2-pyrrolidone and the like.

Suitable solid carriers are, for example, talc, titanium dioxide, pyrophyllite clay, silica, attapulgite clay, kieselguhr, limestone, calcium carbonate, bentonite, calcium montmorillonite, cottonseed husks, wheat flour, soybean flour, pumice, wood flour, ground walnut shells, lignin and similar substances.

A large number of surface-active substances can advantageously be used in both solid and liquid formulations, especially in those formulations which can be diluted with a carrier prior to use. Surface-active substances may be anionic, cationic, non-ionic or polymeric and they can be used as emulsifiers, wetting agents or suspending agents or for other purposes. Typical surface-active substances include, for example, salts of alkyl sulfates, such as diethanolammonium lauryl sulfate; salts of alkylarylsulfonates, such as calcium dodecylbenzenesulfonate; alkylphenol/alkylene oxide addition products, such as nonylphenol ethoxylate; alcohol/alkylene oxide addition products, such as tridecylalcohol ethoxylate; soaps, such as sodium stearate; salts of alkylnaphthalenesulfonates, such as sodium dibutylnaphthalenesulfonate; dialkyl esters of sulfosuccinate salts, such as sodium di(2- ethylhexyl)sulfosuccinate; sorbitol esters, such as sorbitol oleate; quaternary amines, such as lauryltrimethylammonium chloride, polyethylene glycol esters of fatty acids, such as polyethylene glycol stearate; block copolymers of ethylene oxide and propylene oxide; and salts of mono- and di-alkylphosphate esters; and also further substances described e.g. in McCutcheon's Detergents and Emulsifiers Annual, MC Publishing Corp., Ridgewood New Jersey (1981).

Further adjuvants that can be used in pesticidal formulations include crystallisation inhibitors, viscosity modifiers, suspending agents, dyes, anti-oxidants, foaming agents, light absorbers, mixing auxiliaries, antifoams, complexing agents, neutralising or pH-modifying substances and buffers, corrosion inhibitors, fragrances, wetting agents, take-up enhancers, micronutrients, plasticisers, glidants, lubricants, dispersants, thickeners, antifreezes, microbicides, and liquid and solid fertilisers.

The compositions according to the invention can include an additive comprising an oil of vegetable or animal origin, a mineral oil, alkyl esters of such oils or mixtures of such oils and oil derivatives. The amount of oil additive in the composition according to the invention is generally from 0.01 to 10 %, based on the mixture to be applied. For example, the oil additive can be added to a spray tank in the desired concentration after a spray mixture has been prepared. Preferred oil additives comprise mineral oils or an oil of vegetable origin, for example rapeseed oil, olive oil or sunflower oil, emulsified vegetable oil, alkyl esters of oils of vegetable origin, for example the methyl derivatives, or an oil of animal origin, such as fish oil or beef tallow. Preferred oil additives comprise alkyl esters of C8-C22 fatty acids, especially the methyl derivatives of C12-C18 fatty acids, for example the methyl esters of lauric acid, palmitic acid and oleic acid (methyl laurate, methyl palmitate and methyl oleate, respectively). Many oil derivatives are known from the Compendium of Herbicide Adjuvants, 10^th Edition, Southern Illinois University, 2010.

The herbicidal compositions generally comprise from 0.1 to 99 % by weight, especially from 0.1 to 95 % by weight, compounds of formula (I) and from 1 to 99.9 % by weight of a formulation adjuvant which preferably includes from 0 to 25 % by weight of a surface-active substance. The inventive compositions generally comprise from 0.1 to 99 % by weight, especially from 0.1 to 95 % by weight, of compounds of the present invention and from 1 to 99.9 % by weight of a formulation adjuvant which preferably includes from 0 to 25 % by weight of a surface-active substance. Whereas commercial products may preferably be formulated as concentrates, the end user will normally employ dilute formulations.

The rates of application vary within wide limits and depend on the nature of the soil, the method of application, the crop plant, the pest to be controlled, the prevailing climatic conditions, and other factors governed by the method of application, the time of application and the target crop. As a general guideline compounds may be applied at a rate of from 1 to 2000 l/ha, especially from 10 to 1000 l/ha.

Preferred formulations can have the following compositions (weight %): Emulsifiable concentrates: active ingredient: 1 to 95 %, preferably 60 to 90 % surface-active agent: 1 to 30 %, preferably 5 to 20 % liquid carrier: 1 to 80 %, preferably 1 to 35 %

Dusts: active ingredient: 0.1 to 10 %, preferably 0.1 to 5 % solid carrier: 99.9 to 90 %, preferably 99.9 to 99 % Suspension concentrates: active ingredient: 5 to 75 %, preferably 10 to 50 % water: 94 to 24 %, preferably 88 to 30 % surface-active agent: 1 to 40 %, preferably 2 to 30 %

Wettable powders: active ingredient: 0.5 to 90 %, preferably 1 to 80 % surface-active agent: 0.5 to 20 %, preferably 1 to 15 % solid carrier: 5 to 95 %, preferably 15 to 90 %

Granules: active ingredient: 0.1 to 30 %, preferably 0.1 to 15 % solid carrier: 99.5 to 70 %, preferably 97 to 85 %

The composition of the present may further comprise at least one additional pesticide. For example, the compounds according to the invention can also be used in combination with other herbicides or plant growth regulators. In a preferred embodiment the additional pesticide is a herbicide and/or herbicide safener.

The compounds of present invention can also be used in mixture with one or more additional herbicides and/or plant growth regulators. Examples of such additional herbicides or plant growth regulators include acetochlor, acifluorfen (including acifluorfen-sodium), aclonifen, ametryn, amicarbazone, aminopyralid, aminotriazole, atrazine, beflubutamid-M, benquitrione, bensulfuron (including bensulfuron-methyl), bentazone, bicyclopyrone, bilanafos, bipyrazone, bispyribac-sodium, bixlozone, bromacil, bromoxynil, butachlor, butafenacil, carfentrazone (including carfentrazone-ethyl), cloransulam (including cloransulam-methyl), chlorimuron (including chlorimuron-ethyl), chlorotoluron, chlorsulfuron, cinmethylin, clacyfos, clethodim, clodinafop (including clodinafop-propargyl), clomazone, clopyralid, cyclopyranil, cyclopyrimorate, cyclosulfamuron, cyhalofop (including cyhalofop-butyl), 2,4-D (including the choline salt and 2-ethylhexyl ester thereof), 2,4-DB, desmedipham, dicamba (including the aluminium, aminopropyl, bis-aminopropylmethyl, choline, dichloroprop, diglycolamine, dimethylamine, dimethylammonium, potassium and sodium salts thereof) diclosulam, diflufenican, diflufenzopyr, dimethachlor, dimethenamid-P, dioxopyritrione, diquat dibromide, diuron, epyrifenacil, ethalfluralin, ethofumesate, fenoxaprop (including fenoxaprop-P-ethyl), fenoxasulfone, fenpyrazone, fenquinotrione, fentrazamide, flazasulfuron, florasulam, florpyrauxifen (including florpyrauxifen-benzyl), fluazifop (including fluazifop-P-butyl), flucarbazone (including flucarbazone-sodium), flufenacet, flumetsulam, flumioxazin, fluometuron, flupyrsulfuron (including flupyrsulfuron-methyl-sodium), fluroxypyr (including fluroxypyr-meptyl), fomesafen, foramsulfuron, glufosinate (including L-glufosinate and the ammonium salts of both), glyphosate (including the diammonium, isopropylammonium and potassium salts thereof), halauxifen (including halauxifen-methyl), haloxyfop (including haloxyfop-methyl), hexazinone, hydantocidin, imazamox (including R-imazamox), imazapic, imazapyr, imazethapyr, indaziflam, iodosulfuron (including iodosulfuron-methyl-sodium), iofensulfuron (including iofensulfuron-sodium), ioxynil, isoproturon, isoxaflutole, lancotrione, MCPA, MCPB, mecoprop-P, mesosulfuron (including mesosulfuron-methyl), mesotrione, metamitron, metazachlor, methiozolin, metolachlor, metosulam, metribuzin, metsulfuron, napropamide, nicosulfuron, norflurazon, oxadiazon, oxasulfuron, oxyfluorfen, paraquat dichloride, pendimethalin, penoxsulam, phenmedipham, picloram, pinoxaden, pretilachlor, primisulfuron-methyl, prometryne, propanil, propaquizafop, propyrisulfuron, propyzamide, prosulfocarb, prosulfuron, pyraclonil, pyraflufen (including pyraflufen-ethyl), pyrasulfotole, pyridate, pyriftalid, pyrimisulfan, pyroxasulfone, pyroxsulam, quinclorac, quinmerac, quizalofop (including quizalofop-P-ethyl and quizalofop-P-tefuryl), rimisoxafen, rimsulfuron, saflufenacil, sethoxydim, simazine, S-metalochlor, sulfentrazone, sulfosulfuron, tebuthiuron, tefuryltrione, tembotrione, terbuthylazine, terbutryn, tetflupyrolimet, thiencarbazone, thifensulfuron, tiafenacil, tolpyralate, topramezone, tralkoxydim, triafamone, triallate, triasulfuron, tribenuron (including tribenuron-methyl), triclopyr, trifloxysulfuron (including trifloxysulfuron-sodium), trifludimoxazin, trifluralin, triflusulfuron, tripyrasulfone, 3-(2-chloro-4- fluoro-5-(3-methyl-2,6-dioxo-4-trifluoromethyl-3,6-dihydropyrimidin-1 (2H)-yl)phenyl)-5- methyl-4,5-dihydroisoxazole-5-carboxylic acid ethyl ester, 4-hydroxy-1-methoxy-5-methyl-3- [4-(trifluoromethyl)-2-pyridyl]imidazolidin-2-one, 4-hydroxy-1 ,5-dimethyl-3-[4-(trifluoromethyl)- 2-pyridyl]imidazolidin-2-one, 5-ethoxy-4-hydroxy-1-methyl-3-[4-(trifluoromethyl)-2- pyridyl]imidazolidin-2-one, 4-hydroxy-1-methyl-3-[4-(trifluoromethyl)-2-pyridyl]imidazolidin-2- one, 4-hydroxy-1 ,5-dimethyl-3-[1-methyl-5-(trifluoromethyl)pyrazol-3-yl]imidazolidin-2-one, (4R)1-(5-tert-butylisoxazol-3-yl)-4-ethoxy-5-hydroxy-3-methyl-imidazolidin-2-one, 4-amino-3- chloro-5-fluoro-6-(7-fluoro-1 H-indol-6-yl)pyridine-2-carboxylic acid (including agrochemically acceptable esters thereof, for example, methyl 4-amino-3-chloro-5-fluoro-6-(7-fluoro-1 H-indol- 6-yl)pyridine-2-carboxylate, prop-2-ynyl 4-amino-3-chloro-5-fluoro-6-(7-fluoro-1 H-indol-6- yl)pyridine-2-carboxylate and cyanomethyl 4-amino-3-chloro-5-fluoro-6-(7-fluoro-1 H-indol-6- yl)pyridine-2-carboxylate), 3-ethylsulfanyl-N-(1 ,3,4-oxadiazol-2-yl)-5-(trifluoromethyl)- [1 ,2,4]triazolo[4,3-a]pyridine-8-carboxamide, 3-(isopropylsulfanylmethyl)-N-(5-methyl-1 ,3,4- oxadiazol-2-yl)-5-(trifluoromethyl)-[1 ,2,4]triazolo[4,3-a]pyridine-8-carboxamide, 3-

(isopropylsulfonylmethyl)-N-(5-methyl-1 ,3,4-oxadiazol-2-yl)-5-(trifluoromethyl)-

[1 ,2,4]triazolo[4,3-a]pyridine-8-carboxamide, 3-(ethylsulfonylmethyl)-N-(5-methyl-1 ,3,4- oxadiazol-2-yl)-5-(trifluoromethyl)-[1 ,2,4]triazolo[4,3-a]pyridine-8-carboxamide, ethyl 2-[[3-[[3- chloro-5-fluoro-6-[3-methyl-2,6-dioxo-4-(trifluoromethyl)pyrimidin-1 -yl]-2-pyridyl]oxy]acetate and 6-chloro-4-(2,7-dimethyl-1-naphthyl)-5-hydroxy-2-methyl-pyridazin-3-one.

The mixing partners of the compound of formula (I) may also be in the form of esters or salts, as mentioned e.g. in The Pesticide Manual, Fourteenth Edition, British Crop Protection Council, 2006.

The compound of formula (I) can also be used in mixtures with other agrochemicals such as fungicides, nematicides or insecticides, examples of which are given in The Pesticide Manual. The mixing ratio of the compound of formula (I) to the mixing partner is preferably from 1 : 100 to 1000:1.

The mixtures can advantageously be used in the above-mentioned formulations (in which case "active ingredient" relates to the respective mixture of compound of formula (I) with the mixing partner).

Compounds of formula (I) of the present invention may also be combined with herbicide safeners. Examples of such safeners include benoxacor, cloquintocet (including cloquintocetmexyl), cyprosulfamide, dichlormid, fenchlorazole (including fenchlora zoleethyl), fenclorim, fluxofenim, furilazole, isoxadifen (including isoxadifenethyl), mefenpr (in eluding mefenpyr-diethyl), metcamifen and oxabetrinil.

Particularly preferred are mixtures of a compound of formula (I) with cyprosulfamide, isoxadifen (including isoxadifen-ethyl), cloquintocet (including cloquintocet-mexyl) and/or N- (2-methoxybenzoyl)-4-[(methyl-aminocarbonyl)amino]benzenesulfonamide.

The safeners of the compound of formula (I) may also be in the form of esters or salts, as mentioned e.g. in The Pesticide Manual, 14^th Edition (BCPC), 2006. The reference to cloquintocet-mexyl also applies to a lithium, sodium, potassium, calcium, magnesium, aluminium, iron, ammonium, quaternary ammonium, sulfonium or phosphonium salt thereof as disclosed in WO 02/34048, and the reference to fenchlorazole-ethyl also applies to fenchlorazole, etc.

Preferably the mixing ratio of compound of formula (I) to safener is from 100:1 to 1 :10, especially from 20: 1 to 1 : 1 . The mixtures can advantageously be used in the above-mentioned formulations (in which case "active ingredient" relates to the respective mixture of compound of formula (I) with the safener).

The compounds of formula (I) of this invention are useful as herbicides. The present invention therefore further comprises a method for controlling unwanted plants comprising applying to the said plants or a locus comprising them, an effective amount of a compound of the invention or a herbicidal composition containing said compound. ‘Controlling’ means killing, reducing or retarding growth or preventing or reducing germination. Generally the plants to be controlled are unwanted plants (weeds). ‘Locus’ means the area in which the plants are growing or will grow.

The rates of application of compounds of formula (I) may vary within wide limits and depend on the nature of the soil, the method of application (pre-emergence; post-emergence; application to the seed furrow; no tillage application etc.), the crop plant, the weed(s) to be controlled, the prevailing climatic conditions, and other factors governed by the method of application, the time of application and the target crop. The compounds of formula (I) according to the invention are generally applied at a rate of from 10 to 2000 g/ha, especially from 50 to 1000 g/ha. A preferred range is 10-200g/ha.

The application is generally made by spraying the composition, typically by tractor mounted sprayer for large areas, but other methods such as dusting (for powders), drip or drench can also be used.

Useful plants in which the composition according to the invention can be used include crops such as cereals, for example barley and wheat, cotton, oilseed rape, sunflower, maize, rice, soybeans, sugar beet, sugar cane and turf.

Crop plants can also include trees, such as fruit trees, palm trees, coconut trees or other nuts. Also included are vines such as grapes, fruit bushes, fruit plants and vegetables.

Crops are to be understood as also including those crops which have been rendered tolerant to herbicides or classes of herbicides (e.g. ALS-, GS-, EPSPS-, PPO-, ACCase- and HPPD- inhibitors) by conventional methods of breeding or by genetic engineering. An example of a crop that has been rendered tolerant to imidazolinones, e.g. imazamox, by conventional methods of breeding is Clearfield® summer rape (canola). Examples of crops that have been rendered tolerant to herbicides by genetic engineering methods include e.g. glyphosate- and glufosinate-resistant maize varieties commercially available under the trade names RoundupReady® and LibertyLink®.

Crops are also to be understood as being those which have been rendered resistant to harmful insects by genetic engineering methods, for example Bt maize (resistant to European corn borer), Bt cotton (resistant to cotton boll weevil) and also Bt potatoes (resistant to Colorado beetle). Examples of Bt maize are the Bt 176 maize hybrids of NK® (Syngenta Seeds). The Bt toxin is a protein that is formed naturally by Bacillus thuringiensis soil bacteria. Examples of toxins, or transgenic plants able to synthesise such toxins, are described in EP-A-451 878, EP-A-374 753, WO 93/07278, WO 95/34656, WO 03/052073 and EP-A-427 529. Examples of transgenic plants comprising one or more genes that code for an insecticidal resistance and express one or more toxins are KnockOut® (maize), Yield Gard® (maize), NuCOTIN33B® (cotton), Bollgard® (cotton), NewLeaf® (potatoes), NatureGard® and Protexcta®. Plant crops or seed material thereof can be both resistant to herbicides and, at the same time, resistant to insect feeding ("stacked" transgenic events). For example, seed can have the ability to express an insecticidal Cry3 protein while at the same time being tolerant to glyphosate.

Crops are also to be understood to include those which are obtained by conventional methods of breeding or genetic engineering and contain so-called output traits (e.g. improved storage stability, higher nutritional value and improved flavour).

Other useful plants include turf grass for example in golf-courses, lawns, parks and roadsides, or grown commercially for sod, and ornamental plants such as flowers or bushes.

Compounds of formula (I) and compositions of the invention can typically be used to control a wide variety of monocotyledonous and dicotyledonous weed species. Examples of monocotyledonous species that can typically be controlled include Alopecurus myosuroides, Avena fatua, Brachiaria plantag inea, Brom us tectorum, Cyperus esculentus, Digitaria sanguinalis, Echinochloa crus-galli, Lolium perenne, Lolium multiflorum, Panicum miliaceum, Poa annua, Setaria viridis, Setaria faberi and Sorghum bicolor Examples of dicotyledonous species that can be controlled include Abutilon theophrasti, Amaranthus retroflexus, Bidens pilosa, Chenopodium album, Euphorbia heterophylla, Galium aparine, Ipomoea hederacea, Kochia scoparia, Polygonum convolvulus, Sida spinosa, Sinapis arvensis, Solanum nigrum, Stellaria media, Veronica persica and Xanthium strumarium. The compounds of formula (I) are also useful for pre-harvest desiccation in crops, for example, but not limited to, potatoes, soybean, sunflowers and cotton. Pre-harvest desiccation is used to desiccate crop foliage without significant damage to the crop itself to aid harvesting.

Compounds/compositions of the invention are particularly useful in non-selective burn-down applications, and as such may also be used to control volunteer or escape crop plants.

Various aspects and embodiments of the present invention will now be illustrated in more detail by way of example. It will be appreciated that modification of detail may be made without departing from the scope of the invention. The Examples which follow serve to illustrate, but do not limit, the invention

Examples

SYNTHESIS EXAMPLES

Example 1 Preparation of 2-chloro-2-(3-chloro-2-methoxy-phenyl)-2-fluoro-acetic acid (Compound 1-681)

Step 1 Synthesis of ethyl 2-(3-chloro-2-methoxy-phenyl)-2-fluoro-acetate

1-Chloro-3-iodo-2-methoxybenzene (0.900 g, 3.29 mmol), nickel(ll) iodide (0.103 g, 0.329 mmol), zinc (0.065 g, 9.86 mmol), 5,5’-dimethyl-2,2’-bipyridine (0.060 g, 0.329 mmol) and magnesium chloride (0.494 g, 4.93 mmol) were stirred in /V,/V-dimethylacetamide (16 mL). Ethyl chlorofluoroacetate (0.952 g, 6.57 mmol) was added. The reaction was stirred at 80 °C under nitrogen for 1 hour. The reaction mixture was filtered through a plug of silica washing with ethyl acetate and concentrated onto celite for purification. The product was purified by normal phase chromatography (0-50% ethyl acetate/cyclohexane to afford ethyl 2-(3-chloro-

2-methoxy-phenyl)-2-fluoro-acetate (0.447 g, 1.81 mmol, 55%) as a colourless oil. ¹H NMR (400 MHz, chloroform) 5 = 7.49 - 7.42 (m, 1 H), 7.36 - 7.28 (m, 1 H), 7.19 - 7.07 (m, 1 H), 6.12 - 5.92 (m, 1H), 4.36 - 4.21 (m, 2H), 3.94 (s, 3H), 1.31 - 1.23 (t, 3H)

Step 2 Synthesis of ethyl 2-chloro-2-(3-chloro-2-methoxy-phenyl)-2-fluoro-acetate

(Compound 3-681)

Ethyl 2-(3-chloro-2-methoxy-phenyl)-2-fluoro-acetate (0.438 g, 1.78 mmol) was stirred in tetrahydrofuran (9 mL) at -78 °C. Sodium bis(trimethylsilyl)amide in tetrahydrofuran (1 mol/L, 2.13 mL, 2.13 mmol) was added dropwise. The reaction was stirred for 1 hour before the addition of /V-chlorosuccinimide (0.287 g, 2.13 mmol) in tetrahydrofuran (1 mL). The reaction mixture was slowly warmed to room temperature and stirred overnight. The reaction was quenched with water and extracted twice with ethyl acetate. The organics were washed with brine, dried (MgSCL), filtered and concentrated under vacuum to afford ethyl 2-chloro-2-(3- chloro-2-methoxy-phenyl)-2-fluoro-acetate (Compound 3-681) (0.500 g, 1.78 mmol, 100%) as a pale yellow oil. The product was used in the next step without further purification.

¹H NMR (400 MHz, chloroform) 5 = 7.80 (br d, 1 H), 7.51 (dt, 1H), 7.18 (m, 1 H), 4.32 (m, 2H), 3.90 (s, 3H), 1.26 (t, 3H)

Also prepared by this general method were:

Ethyl 2-chloro-2-(2-chloro-3-methyl-phenyl)-2-fluoro-acetate (Compound 3-139)

¹H NMR (400 MHz, chloroform) 5 = 7.27 - 7.40 (m, 3H), 4.33 - 4.38 (m, 2H), 2.42 (s, 3H), 1.32 (t, 3H)

Ethyl 2-chloro-2-(2-cyano-3-methoxy-phenyl)-2-fluoro-acetate (Compound 3-640)

¹H NMR (400 MHz, chloroform) 5 = 7.58 - 7.65 (t, 1 H), 7.44 - 7.49 (d, 1 H), 7.08 - 7.14 (d, 1 H), 4.34 - 4.47 (m, 2H), 3.98 (s, 3H), 1.37 (t, 3H)

Ethyl 2-chloro-2-(3-cyano-2-methyl-phenyl)-2-fluoro-acetate (Compound 3-248) ¹H NMR (400 MHz, chloroform) 5 = 7.99 - 8.05 (d, 1 H), 7.71 - 7.76 (d, 1 H), 7.39 - 7.45 (t, 1 H), 4.32 - 4.40 (m, 2H), 2.59 (s, 3H), 1.34 (t, 3H)

Ethyl 2-chloro-2-(2,3-dichlorophenyl)-2-fluoro-acetate (Compound 3-37)

¹H NMR (400 MHz, chloroform) 5 = 7.83 - 7.88 (m, 1 H), 7.58 - 7.61 (m, 1 H), 7.31 - 7.37 (t, 1 H), 4.33 - 4.40 (M, 2H), 1 .32 (t, 3H)

Ethyl 2-chloro-2-(3-chloro-2-ethyl-phenyl)-2-fluoro-acetate (Compound 3-288)

¹H NMR (400 MHz, chloroform) 5 = 7.71 (d, 1 H), 7.42 (m, 1 H), 7.22 (t, 1 H), 4.34 (m, 2H), 2.97 - 2.81 (m, 1 H), 2.79 - 2.68 (m, 1 H), 1.27 (t, 3H), 1.18 (t, 3H)

Ethyl 2-chloro-2-(3-chloro-2-methyl-phenyl)-2-fluoro-acetate (Compound 3-238)

¹H NMR (400 MHz, chloroform) 5 = 7.72 (d, 1 H), 7.43 (d, 1 H), 7.22 (t, 1 H), 4.42 (m, 2H), 2.36 (s, 3H), 1.31 (t, 3H)

Ethyl 2-chloro-2-(2-chloro-4-fluoro-phenyl)-2-fluoro-acetic acid (Compound 3-132)

¹H NMR (400 MHz, chloroform) 5 = 8.11 (dd, 1 H), 7.95 (dd, 1 H), 7.85 (dd, 1 H), 4.34 (m, 2H), 1.29 (t, 3H)

Step 3 Synthesis of 2-chloro-2-(3-chloro-2-methoxy-phenyl)-2-fluoro-acetic acid (Compound 1-681)

Ethyl 2-chloro-2-(3-chloro-2-methoxy-phenyl)-2-fluoro-acetate (0.500 g, 1.78 mmol) was dissolved in tetra hydrofuran (9 mL) and water (9 mL). Lithium hydroxide (0.130 g, 5.34 mmol) was added. The reaction was stirred vigorously at room temperature for 2 hours. The reaction was quenched with 2M HCI and extracted twice with ethyl acetate. The organics were washed with brine, dried (MgSCL), filtered and concentrated under vacuum. The crude mixture was purified by HPLC to afford 2-chloro-2-(3-chloro-2-methoxy-phenyl)-2-fluoro-acetic acid (Compound 1-681) (0.132 g, 0.522 mmol, 29%) as a colourless solid.

¹H NMR (400 MHz, DMSO-d6) 6 = 7.81 (td, 1 H), 7.71 (td, 1 H), 7.32 (dt, 1 H), 3.81 (s, 3H) Also prepared by this general method were:

2-Chloro-2-(2-chloro-3-methyl-phenyl)-2-fluoro-acetic acid (Compound 1-139)

¹H NMR (400 MHz, chloroform) 5 = 7.83 (d, 1 H), 7.42 - 7.37 (m, 1 H), 7.33 - 7.28 (m, 1 H), 5.59

- 5.25 (br s, 1 H), 2.43 (s, 3H)

2-Chloro-2-(2-cyano-3-methoxy-phenyl)-2-fluoro-acetic acid (Compound 1-640)

¹H NMR (400 MHz, DMSO-d6) 5 = 7.86 - 7.78 (m, 1 H), 7.49 - 7.44 (m, 2H), 3.98 (s, 3H)

2-Chloro-2-(2-chloro-4-fluoro-phenyl)-2-fluoro-acetic acid (Compound 1-132)

¹H NMR (400 MHz, DMSO-d6) 5 = 8.00 (ddd, 1 H), 7.66 (dd, 1 H), 7.40 (dt, 1 H)

2-Chloro-2-(3-chloro-2-methyl-phenyl)-2-fluoro-acetic acid (Compound 1-238)

¹H NMR (400 MHz, DMSO-d6) 5 = 7.75 (d, 1 H), 7.63 (d, 1 H), 7.44 - 7.35 (m, 1 H), 2.34 (d, 3H)

2-Chloro-2-(3-cyano-2-methyl-phenyl)-2-fluoro-acetic acid (Compound 1-248)

¹H NMR (400 MHz, DMSO-d6) 5 = 8.07 (d, 1 H), 7.98 (d, 1 H), 7.58 (t, 1 H)

2-Chloro-2-(3-chloro-2-ethyl-phenyl)-2-fluoro-acetic acid (Compound 1-288)

¹H NMR (400 MHz, chloroform) 5 = 7.76 (d, 1 H), 7.51 (d, 1 H), 7.24 (br d, 1 H), 2.96 - 2.87 (m, 1 H), 2.80 - 2.70 (m, 1 H), 1 .21 (t, 3H)

Example 2 Preparation of 2-chloro-2-fluoro-2-(8-quinolyl)acetic acid (Compound 1-799)

Step 1 Synthesis of ethyl 2-fluoro-2-(8-quinolyl)acetate

Ethyl 2-(8-quinolyl)acetate (0.290 g, 1.35 mmol) was stirred in tetra hydrofuran (2.7 mL) at - 78 °C to which sodium bis(trimethylsilyl)amide in tetrahydrofuran (1 mol/L, 1.62 mL, 1.62 mmol) was added dropwise. The reaction was stirred for 30 mins before addition of /V- fluorobenzenesulfonimide (0.492 g, 1.48 mmol) in 4 mL of tetra hydrofuran. The reaction mixture was slowly warmed to room temperature and stirred for 1 hour. The reaction was quenched with 1 M HCI and extracted twice with ethyl acetate. The organics were washed with brine, dried (MgSCL), filtered and concentrated under vacuum. The crude product was purified by reverse phase chromatography (40-80% acetonitrile/water) to give ethyl 2-fluoro- 2-(8-quinolyl)acetate (0.220 g, 0.943 mmol, 70%) as a yellow oil.

¹H NMR (400 MHz, chloroform) 5 = 8.97 (dd, 1 H), 8.20 (dd, 1 H), 7.94 - 7.85 (m, 2H), 7.64 - 7.57 (m, 1 H), 7.47 (dd, 1 H), 7.10 - 6.93 (m, 1 H), 4.28 (dddd, 2H), 1.23 (t, 3H)

Step 2 Synthesis of ethyl 2-chloro-2-fluoro-2-(8-quinolyl)acetate (Compound 3-799)

Ethyl 2-fluoro-2-(8-quinolyl)acetate (0.230 g, 0.986 mmol) was stirred in tetrahydrofuran (5 mL) at -78 °C to which sodium bis(trimethylsilyl)amide in tetrahydrofuran (1 mol/L, 1.18 mL, 1.18 mmol) was added dropwise. The reaction was stirred for 1 hour before addition of /V- chlorosuccinimide (0.160 g, 1.18 mmol) in tetra hydrofuran (1 mL). The reaction mixture was slowly warmed to room temperature and stirred overnight. The reaction was quenched with water and extracted twice with ethyl acetate. The organics were washed with brine, dried (MgSCL), filtered and concentrated under vacuum to afford crude ethyl 2-chloro-2-fluoro-2-(8- quinolyl)acetate (Compound 3-799) as a pale yellow oil, which was used without further purification in the next step.

¹H NMR (400 MHz, DMSO-d6) 5 = 8.86 - 8.89 (m, 1 H), 8.32 - 8.40 (m, 1 H), 8.18 - 8.22 (m, 1 H), 7.94 - 7.99 (m, 1 H), 7.63 - 7.68 (m, 1 H), 7.44 - 7.49 (m, 1 H), 4.28 - 4.38 (m, 2H), 1.22 (t, 3H)

Also prepared by this general method were:

Methyl 2-chloro-2-(3-chlorophenyl)-2-fluoro-acetic acid (Compound 2-017)

Methyl 2-chloro-2-(2,3-dichlorophenyl)-2-fluoro-acetate (Compound 2-137)

¹H NMR (400 MHz, DMSO-d6) 5 = 7.99 (d, 1 H), 7.91 (d, 1 H), 7.61 (t, 1 H), 3.88 (s, 3H) Methyl 2-(4-bromophenyl)-2-chloro-2-fluoro-acetate (Compound 2-003) ¹H NMR (400 MHz, chloroform) 5 = 7.62 - 7.54 (m, 4H), 3.78 (s, 3H) Step 3 Synthesis of 2-chloro-2-fluoro-2-(8-quinolyl)acetic acid (Compound 1-799)

Ethyl 2-chloro-2-fluoro-2-(8-quinolyl)acetate (0.264 g, 0.986 mmol) was dissolved in tetra hydrofuran (5 mL) and water (9 mL) to which lithium hydroxide (0.072 g, 2.96 mmol) was added. The reaction was stirred vigorously at room temperature for 2 hours. The reaction was quenched with 2M HCI and extracted twice with ethyl acetate. The organics were washed with brine, dried (MgSOt), filtered and concentrated under vacuum. The crude product was purified by HPLC to afford 2-chloro-2-fluoro-2-(8-quinolyl)acetic acid (Compound 1-799) (0.059 g, 0.25 mmol, 25%) as a pale brown solid.

¹H NMR (400 MHz, DMSO-d6) 5 = 8.91 (dd, 1 H), 8.50 (dd, 1 H), 8.31 (td, 1 H), 8.20 (d, 1 H), 7.75 (t, 1 H), 7.64 (dd, 1 H)

Also prepared by this general method were:

2-Chloro-2-(3-chlorophenyl)-2-fluoro-acetic acid (Compound 1-017)

¹H NMR (400 MHz, DMSO-d6) 5 = 7.60 (s, 1 H), 7.53 (d, 1 H), 7.42 - 7.38 (m, 2H)2-(4- Bromophenyl)-2-chloro-2-fluoro-acetic acid (Compound 1-003)

2-Chloro-2-(2,3-dichlorophenyl)-2-fluoroacetic acid (Compound 1-137)

¹H NMR (400 MHz, DMSO-d6) 5 = 7.94 (dd, 1 H), 7.89 - 7.83 (m, 1 H), 7.61 - 7.51 (m, 1 H)

Example 3 Preparation of 2-chloro-2-(2-chlorophenyl)-2-fluoro-acetic acid (Compound 1-125)

Step 1 Synthesis of methyl 2-(2-chlorophenyl)-2-fluoro-acetate

Diethylaminosulfur trifluoride (0.89 g, 5.5 mmol) was added dropwise to a stirred solution of ethyl 2-(2-chlorophenyl)-2-hydroxy-acetate (552 mg, 2.75 mmol) in dry dichloromethane (14 mL) at 0 °C under nitrogen. The resulting mixture was stirred at ambient temperature for 17 hours, then saturated aqueous sodium bicarbonate added to bring the pH to >7. The resulting mixture was extracted with dichloromethane and the organic extract passed through a phase separation cartridge and concentrated under reduced pressure to leave a yellow oil, which was purified by flash column chromatography (0-70% EtOAc/c-hexane) to provide methyl 2- (2-chlorophenyl)-2-fluoro-acetate (484 mg) as a pale yellow liquid.

¹H NMR (400 MHz, chloroform) 5 = 7.41 - 7.33 (m, 1 H), 7.31 - 7.25 (m, 1 H), 7.24 - 7.12 (m, 2H), 6.19 - 5.99 (m, 1 H), 3.63 (s, 3H)

Step 2 Synthesis of methyl 2-chloro-2-(2-chlorophenyl)-2-fluoro-acetic acid (Compound 2- 125)

Sodium bis(trimethylsilyl)amide in tetrahydrofuran (1 mol/L, 3.32 mL, 3.32 mmol) was added dropwise to a stirred solution of methyl 2-(2-chlorophenyl)-2-fluoro-acetate (600 mg, 2.96 mmol) in tetrahydrofuran (10 mL) at -78 °C under nitrogen. The resulting solution was stirred for 30 minutes at -78 °C, then /V-chlorosuccinimide (430 mg, 3.22 mmol) added portionwise. The resulting mixture was slowly warmed to room temperature and stirred for 5 hours, then saturated aqueous ammonium chloride (15 ml) was added and the mixture extracted with ethyl acetate (3 x 10 ml). The combined organic extracts were washed with water and brine, dried over sodium sulphate, filtered and concentrated under vacuum to leave a residue which was purified by column chromatography, eluting with 0-20% ethyl acetate in petroleum ether, to provide methyl 2-chloro-2-(2-chlorophenyl)-2-fluoro-acetic acid (Compound 2-125) (400 mg) as a yellow oil.

Step 3 Synthesis of 2-chloro-2-(2-chlorophenyl)-2-fluoro-acetic acid (Compound 1-125)

Lithium hydroxide monohydrate (186 mg, 4.43 mmol) was added to a solution of methyl 2- chloro-2-(3-chlorophenyl)-2-fluoro-acetic acid (350 mg, 1.48 mmol) in tetra hydrofuran (8 mL), methanol (2 ml) and water (9 mL). The resulting mixture was stirred at ambient temperature for 6 hours, then concentrated under reduced pressure and 2N hydrochloric acid added to adjust the pH to 2-3. The resulting mixture was extracted ethyl acetate (3 x 5 ml) and the combined organic extracts washed with water and brine, dried over sodium sulphate, filtered and concentrated under vacuum to leave a residue which was purified by HPLC to afford 2- chloro-2-(2-chlorophenyl)-2-fluoro-acetic acid (Compound 1-125) (35 mg) as a white solid.

¹H NMR (400 MHz, DMSO-d6) 5 = 7.95 (d, 1 H), 7.62 - 7.51 (m, 3H)

BIOLOGICAL EXAMPLES

Pre-emergence biological efficacy

Seeds of weeds and/or crops were sown in standard soil in pots. After cultivation for one day under controlled conditions in a glasshouse (at 24/19°C, day/night; 16 hours light), the plants were sprayed with an aqueous spray solution derived from the formulation of the technical active ingredient in a small amount of acetone and a special solvent and emulsifier mixture referred to as IF50 (11.12% Emulsogen EL360 TM + 44.44% N-methylpyrrolidone + 44.44% Dowanol DPM glycol ether), to create a 50g/l solution which was then diluted using 0.2% Genapol XO80 as diluent to give the desired final dose of test compound.

The test plants were then grown under controlled conditions in the glasshouse (at 24/18°C, day/night; 15 hours light; 50 % humidity) and watered twice daily. After 13 days the test was evaluated (100 = total damage to plant; 0 = no damage to plant). The results are shown in Table 2 below.

Table 2

Post-emergence biological efficacy

Seeds of weeds and/or crops were sown in standard soil in pots. After cultivation for 14 days under controlled conditions in a glasshouse (at 24/19°C, day/night; 16 hours light), the plants were sprayed with an aqueous spray solution derived from the formulation of the technical active ingredient in a small amount of acetone and a special solvent and emulsifier mixture referred to as IF50 (11.12% Emulsogen EL360 TM + 44.44% N-methylpyrrolidone + 44.44% Dowanol DPM glycol ether), to create a 50g/l solution which was then diluted using 0.2% Genapol XO80 as diluent to give the desired final dose of test compound.

The test plants were then grown under controlled conditions in the glasshouse (at 24/18°C, day/night; 15 hours light; 50 % humidity) and watered twice daily. After 13 days the test was evaluated (100 = total damage to plant; 0 = no damage to plant). The results are shown in Table 3 below.

Table 3

The invention is defined by the claims.

Claims

Claims

1 . A compound of Formula I

wherein:

R¹, R², R³, R⁴ and R⁵ are independently selected from the group consisting of hydrogen, halogen, amino, cyano, nitro, hydroxyl, Ci-salkyl, Cs-ecycloalkyl, Ci- 2haloalkyl, cyanomethyl, Ci-2alkoxyCi-2alkyl, Ci-4alkoxy, Ci-2haloalkoxy, C2-3alkenyl, C2- salkynyl, halophenyl, Ci-2alkoxycarbonyl, Ci-2alkylsulfanyl, Ci-2alkylsulphinyl and C1- 2alkylsulfonyl; or

R¹ and R² together with the carbon atoms to which they are attached form a 5- or 6- membered ring, which may optionally be substituted by one or more groups selected from halogen, cyano, hydroxyl, Ci-salkyl, Ci-2haloalkyl, and Ci-4alkoxy, and wherein the 6-membered ring contains zero, one or two nitrogen atoms and wherein the 5- membered ring contains one or two heteroatoms independently selected from the group consisting of nitrogen and oxygen;

R⁶ is selected from the group consisting of hydrogen, Ci-ealkyl and arylCi-2alkyl; and wherein at least one of R¹ to R⁵ is hydrogen and at least one of R¹ to R⁵ is not hydrogen, or an agronomically acceptable salt of said compound.

2. A compound according to claim 1 , wherein R¹ is selected from the group consisting of hydrogen, halogen, amino, cyano, nitro, hydroxyl, Ci-4alkyl, C3-4cycloalkyl, C1- 2haloalkyl, Ci-4alkoxy, Ci-2haloalkoxy, C2-3alkenyl, C2-3alkynyl, halophenyl and C1- 2alkylsulfanyl, more preferably hydrogen, fluorine, chlorine, bromine, amino, cyano, Ci- 4alkyl, cyclopropyl, halomethyl, Ci-3alkoxy, Cihaloalkoxy, vinyl, ethynyl and methylsulfanyl, most preferably chlorine, bromine, cyano, methyl, ethyl, cyclopropyl, difluoromethyl, trifluoromethyl, methoxy, ethoxy, vinyl and ethynyl. A compound according to claim 1 or 2, wherein R² is selected from the group consisting of hydrogen, halogen, amino, cyano, nitro, hydroxyl, Ci-4alkyl, C3-4cycloalkyl, Ci- 2haloalkyl, Ci-4alkoxy, Ci-2haloalkoxy, C2-3alkenyl, C2-3alkynyl, halophenyl and Ci- 2alkylsulfanyl, more preferably hydrogen, fluorine, chlorine, bromine, cyano, Ci-4alkyl, cyclopropyl, halomethyl, Ci-3alkoxy, Cihaloalkoxy, vinyl, ethynyl, fluorophenyl and methylsulfanyl, most preferably hydrogen, chlorine, bromine, cyano, methyl, cyclopropyl, difluoromethyl, trifluoromethyl, methoxy, vinyl and ethynyl. A compound according to claim 1 , wherein R¹ and R² together with the carbon atoms to which they are attached form a 5-membered ring containing one or two heteroatoms independently selected from the group consisting of nitrogen and oxygen, preferably the 5-membered ring contains two oxygen atoms. A compound according to claim 4, wherein the 5-membered ring is partially or fully saturated. A compound according to any of the preceding claims, wherein R³ is selected from the group consisting of hydrogen, halogen, amino, cyano, hydroxyl, Ci-Csalkyl, Ci- 2haloalkyl, Ci-C4alkoxy, C2-C3alkenyl, C2-C3alkynyl, Ci-C2haloalkoxy and halophenyl, more preferably hydrogen, halogen, amino, trifluoromethoxy, trifluoromethyl, methyl, tert-butyl and methoxy, most preferably hydrogen, fluorine and chlorine. A compound according to any of the preceding claims, wherein R⁴ is selected from the group consisting of hydrogen, amino, fluorine, chlorine, methoxy; preferably hydrogen. A compound according to any of the preceding claims, wherein R⁵ is selected from the group consisting of hydrogen, fluorine, chlorine, amino, nitro and methoxy; preferably selected from hydrogen, chlorine and methoxy. A compound according to any of the preceding claims, wherein R⁶ is selected from the group consisting of hydrogen, Ci-Csalkyl and benzyl; preferably hydrogen. Use of a compound according to any of claims 1 to 9 as a herbicide. A herbicidal composition according to claim 10, further comprising at least one additional pesticide. A herbicidal composition according to claim 11 , wherein the additional pesticide is a herbicide or herbicide safener. A method of controlling weeds at a locus comprising application to the locus of a weed controlling amount of a compound of Formula (I) or an agronomically acceptable salt of said compound as defined in any one of claims 1 to 9 or a herbicidal composition according to any one of claims 10 to 12.