WO2024017762A1

WO2024017762A1 - Herbicidal compounds

Info

Publication number: WO2024017762A1
Application number: PCT/EP2023/069535
Authority: WO
Inventors: Sarah Armstrong; Paul Matthew BURTON; Ramya Rajan; Nicholas John Taylor
Original assignee: Syngenta Crop Protection Ag
Priority date: 2022-07-19
Filing date: 2023-07-13
Publication date: 2024-01-25

Abstract

The present invention related to compounds of Formula (I): or an agronomically acceptable salt thereof, wherein R¹, R², R³, R⁴ and R⁵ are as described herein. The invention further relates to compositions comprising said compounds, to methods of controlling weeds using said compositions, to the use of Compounds of Formula (I) as a herbicide, and intermediates used to make said compounds.

Description

HERBICIDAL COMPOUNDS

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

N-(tetrazol-5-yl)arylcarboxamides are disclosed in, for example, WO2012/028579, WO2021/204665 & WO2021/204669. The present invention relates to novel arylcarboxamides.

Thus, according to the present invention there is provided a compound of Formula (I):

or an agronomically acceptable salt thereof, wherein: -

R¹ is selected from the group consisting of Ci-C4alkyl-, Ci-C4haloalkyl-, Ci-C4alkoxy-Ci- C4alkyl- and Ci-C4haloalkoxy-Ci-C4alkyl-;

R² is selected from the group consisting of halogen, Ci-Cealkyl-, Ci-Qalkoxy-, Ci-Ce haloalkyl- and -S(O)_pCi-C6alkyl;

R³ is Ci-Cehaloalkyl; R⁴ is selected from the group consisting of hydrogen, Ci-C4alkyl, Cs-Cecycloalkyl-, Ci- C4haloalkyl, Ci-C4alkoxy-Ci-C4alkyl-, Ci-C4haloalkoxy-Ci-C4alkyl-, aryl or a 5- or 6- membered heteroaryl wherein the aryl or 5- or 6-membered heteroaryl is optionally substituted by one or more substituents independently selected from the group consisting of halogen, C1-C3 alkyl (e.g methyl), Ci-Cshaloalkyl, Ci-Csalkoxy- and -S(O)_pCi-C3alkyl; and

R⁵ is selected from the group consisting of hydrogen, Ci-C4alkyl, Cs-Cecycloalkyl-, Ci- C4haloalkyl, Ci-C4alkoxy-Ci-C4alkyl-, Ci-C4haloalkoxy-Ci-C4alkyl-, aryl or a 5- or 6- membered heteroaryl wherein the aryl or 5- or 6-membered heteroaryl is optionally substituted by one or more substituents independently selected from the group consisting of halogen, C1-C3 alkyl (e.g methyl), Ci-Cshaloalkyl, Ci-Csalkoxy- and -S(O)_pCi-C3alkyl; or

R⁴ and R⁵ together with the nitrogen atom to which they are attached form a saturated 4-, 5- or 6-membered heterocycle optionally containing one or two additional heteroatoms independently selected from O, N- and S(O)_P; and

Z is -CH₂- or -CH2CH2-; and p is independently 0, 1 or 2.

Ci-Cealkyl and Ci-C4alkyl groups include, for example, methyl (Me, CH3), ethyl (Et, C2H5), w-propyl (z?-Pr), isopropyl (z-Pr), rz-butyl (z?-Bu), isobutyl (z-Bu), .sec-butyl and tert-butyl (t-Bu).

Cs-Cecycloalkyl- includes cyclopropyl (c-propyl (c-Pr)), cyclobutyl (c-butyl (c-Bu)), cyclopentyl (c-pentyl) and cyclohexyl (c-hexyl).

Ci-O, alkoxy- includes, for example, methoxy- and ethoxy-. Halogen (or halo) encompasses fluorine, chlorine, bromine or iodine. The same correspondingly applies to halogen in the context of other definitions, such as haloalkyl.

Ci-Cehaloalkyl includes, for example, fluoromethyl-, difluoromethyl-, trifluoromethyl-, chloromethyl-, di chloromethyl-, trichloromethyl-, 2,2,2-trifluoroethyl-, 2,2-difluoroethyl, 1,1- difluoroethyl, 1 , 1 ,2,2-tetrafluoroethyl, 2-fluoroethyl-, 2-chloroethyl-, pentafluoroethyl-, 1,1- difluoro-2,2,2-trichloroethyl-, 2,2,3,3-tetrafluoroethyl-, 2,2,2-trichloroethyl-, heptafluoro-n- propyl and perfluoro-n-hexyl. Ci-C4haloalkyl includes, for example, fluoromethyl-, difluoromethyl-, trifluoromethyl-, chloromethyl-, dichloromethyl-, trichloromethyl-, 2,2,2- trifluoroethyl-, 2-fluoroethyl-, 2-chloroethyl-, pentafluoroethyl-, l,l-difluoro-2,2,2- trichloroethyl-, 2,2,3,3-tetrafluoroethyl-, 2,2,2-trichloroethyl- and heptafluoro-n-propyl-.

Ci-C4alkoxy-Ci-C4alkyl- includes, for example, methoxyethyl-.

Ci-C4haloalkoxy-Ci-C4alkyl- includes, for example, trifluoromethoxyethyl-.

Ci-Cealkyl-S- (alkylthio) is, for example, methylthio, ethylthio, propylthio, isopropylthio, w-butylthio, isobutylthio, sec-butylthio or tert-butylthio, preferably methylthio or ethylthio.

Ci-Cealkyl-S(O)- (alkylsulfinyl) is, for example, methylsulfinyl, ethylsulfinyl, propylsulfinyl, isopropylsulfinyl, n-butylsulfinyl, isobutylsulfinyl, sec-butylsulfinyl or tertbutylsulfinyl, preferably methylsulfinyl or ethylsulfinyl.

Ci-C6alkyl-S(O)2- (alkylsulfonyl) is, for example, methylsulfonyl, ethylsulfonyl, propylsulfonyl, isopropylsulfonyl, n-butylsulfonyl, isobutylsulfonyl, sec-butylsulfonyl or tertbutylsulfonyl, preferably methylsulfonyl or ethylsulfonyl.

In a preferred embodiment of the present invention, R¹ is selected from the group consisting of methyl, ethyl and /?-propyl, preferably methyl. In a preferred embodiment of the present invention, R² is selected from the group consisting of methyl, Cl, -CF3 and -SChmethyl, more preferably Cl.

In another preferred embodiment of the present invention, R³ is -CF3 or -CHF2.

In one embodiment of the present invention, R⁴ is aryl wherein the aryl is phenyl, more preferably 4-fluorophenyl or 4-MeO-phenyl.

In another embodiment of the present invention, R⁴ is a 5- or 6-membered heteroaryl which contains one, two or three heteroatoms independently selected from the group consisting of O, N and S and wherein said heteroaryl is optionally substituted as previously described. In a more specific embodiment, the 5- or 6-membered heteroaryl is selected from the group consisting of R^4a, R^4b, R^4C, R^4d, R^4e, R^4f, R^4g, R⁴¹¹, R⁴ⁱ, R^4j and R^4k:

In another embodiment of the present invention R⁴ is selected from the group consisting of Ci-Cealkyl- (preferably methyl or ethyl), Ci-C4alkoxy-Ci-C4alkyl- (preferably methoxymethyl-) and Cs-Cecycloalkyl- (preferably cyclopropyl).

In another embodiment of the present invention R⁵ is hydrogen or Ci-Cealkyl- (preferably methyl), most preferably methyl.

In one embodiment of the present invention, R⁴ is selected from the group consisting of methyl, ethyl, methoxyethyl- and cyclopropyl and R⁵ is hydrogen.

In another embodiment of the present invention R⁴ and R⁵ together with the nitrogen atom to which they are bonded form a saturated 4-, 5- or 6-membered heterocycle optionally containing one or two additional heteroatoms independently selected from O, N- and S(O)_P. In a more specific embodiment, R⁴ and R⁵ are represented by -C(O)-CH2CH2CH2CH2-, -CH2CH2OCH2CH2-, - C(O)CH2CH₂CH2-, -CH2CH2CH2CH2CH2- or -CH2CH2CH2CH2-.

In one embodiment of the present invention, Z is -CH2-. In another embodiment of the present invention, Z is -CH2CH2-

Compounds of Formula (I) (and certain intermediate compounds used to synthesise compound of Formula (I)) may contain asymmetric centres and may be present as a single enantiomer, pairs of enantiomers in any proportion or, where more than one asymmetric centre are present, contain diastereoisomers in all possible ratios. Typically one of the enantiomers has enhanced biological activity compared to the other possibilities.

The present invention also includes all possible geometric and tautomeric forms of a compound of formula (I).

The present invention also includes agronomically acceptable salts that the compounds of Formula (I) may form with amines (for example ammonia, dimethylamine and triethylamine), alkali metal and alkaline earth metal bases or quaternary ammonium bases. Among the alkali metal and alkaline earth metal hydroxides, oxides, alkoxides and hydrogen carbonates and carbonates used as salt formers, emphasis is to be given to the hydroxides, alkoxides, oxides and carbonates of lithium, sodium, potassium, magnesium and calcium, but especially those of sodium, magnesium and calcium. The corresponding trimethylsulfonium salt may also be used.

The compounds of Formula (I) according to the invention can be used as herbicides by themselves, but they are generally formulated into herbicidal compositions using formulation adjuvants, such as carriers, solvents and surface-active agents (SFAs). Thus, the present invention further provides a herbicidal composition comprising a herbicidal compound of the present invention and an agriculturally acceptable formulation adjuvant. The composition can be in the form of concentrates which are diluted prior to use, although ready-to-use compositions can also be made. The final dilution is usually made with water, but can be made instead of, or in addition to, water, with, for example, liquid fertilisers, micronutrients, biological organisms, oil or solvents.

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 compositions can be chosen from a number of formulation types, many of which are known from the Manual on Development and Use of FAO Specifications for Plant Protection Products, 5th Edition, 1999. These include dustable powders (DP), soluble powders (SP), water soluble granules (SG), water dispersible granules (WG), wettable powders (WP), granules (GR) (slow or fast release), soluble concentrates (SL), oil miscible liquids (OL), ultra low volume liquids (UL), emulsifiable concentrates (EC), dispersible concentrates (DC), emulsions (both oil in water (EW) and water in oil (EO)), micro-emulsions (ME), suspension concentrates (SC), aerosols, capsule suspensions (CS) and seed treatment formulations. The formulation type chosen in any instance will depend upon the particular purpose envisaged and the physical, chemical and biological properties of the compound of Formula (I).

Dustable powders (DP) may be prepared by mixing a compound of Formula (I) with one or more solid diluents (for example natural clays, kaolin, pyrophyllite, bentonite, alumina, montmorillonite, kieselguhr, chalk, diatomaceous earths, calcium phosphates, calcium and magnesium carbonates, sulphur, lime, flours, talc and other organic and inorganic solid carriers) and mechanically grinding the mixture to a fine powder.

Soluble powders (SP) may be prepared by mixing a compound of Formula (I) with one or more water-soluble inorganic salts (such as sodium bicarbonate, sodium carbonate or magnesium sulphate) or one or more water-soluble organic solids (such as a polysaccharide) and, optionally, one or more wetting agents, one or more dispersing agents or a mixture of said agents to improve water dispersibility/solubility. The mixture is then ground to a fine powder. Similar compositions may also be granulated to form water soluble granules (SG).

Wettable powders (WP) may be prepared by mixing a compound of Formula (I) with one or more solid diluents or carriers, one or more wetting agents and, preferably, one or more dispersing agents and, optionally, one or more suspending agents to facilitate the dispersion in liquids. The mixture is then ground to a fine powder. Similar compositions may also be granulated to form water dispersible granules (WG).

Granules (GR) may be formed either by granulating a mixture of a compound of Formula (I) and one or more powdered solid diluents or carriers, or from pre-formed blank granules by absorbing a compound of Formula (I) (or a solution thereof, in a suitable agent) in a porous granular material (such as pumice, attapulgite clays, fuller's earth, kieselguhr, diatomaceous earths or ground corn cobs) or by adsorbing a compound of Formula (I) (or a solution thereof, in a suitable agent) on to a hard core material (such as sands, silicates, mineral carbonates, sulphates or phosphates) and drying if necessary. Agents which are commonly used to aid absorption or adsorption include solvents (such as aliphatic and aromatic petroleum solvents, alcohols, ethers, ketones and esters) and sticking agents (such as polyvinyl acetates, polyvinyl alcohols, dextrins, sugars and vegetable oils). One or more other additives may also be included in granules (for example an emulsifying agent, wetting agent or dispersing agent).

Dispersible Concentrates (DC) may be prepared by dissolving a compound of Formula (I) in water or an organic solvent, such as a ketone, alcohol or glycol ether. These solutions may contain a surface active agent (for example to improve water dilution or prevent crystallisation in a spray tank).

Emulsifiable concentrates (EC) or oil-in-water emulsions (EW) may be prepared by dissolving a compound of Formula (I) in an organic solvent (optionally containing one or more wetting agents, one or more emulsifying agents or a mixture of said agents). Suitable organic solvents for use in ECs include aromatic hydrocarbons (such as alkylbenzenes or alkylnaphthalenes, exemplified by SOLVESSO 100, SOLVESSO 150 and SOLVESSO 200; SOLVESSO is a Registered Trade Mark), ketones (such as cyclohexanone or methylcyclohexanone) and alcohols (such as benzyl alcohol, furfuryl alcohol or butanol), N- alkylpyrrolidones (such as N-methylpyrrolidone or N-octylpyrrolidone), dimethyl amides of fatty acids (such as Cs-Cio fatty acid dimethylamide) and chlorinated hydrocarbons. An EC product may spontaneously emulsify on addition to water, to produce an emulsion with sufficient stability to allow spray application through appropriate equipment. Preparation of an EW involves obtaining a compound of Formula (I) either as a liquid (if it is not a liquid at room temperature, it may be melted at a reasonable temperature, typically below 70°C) or in solution (by dissolving it in an appropriate solvent) and then emulsifying the resultant liquid or solution into water containing one or more SFAs, under high shear, to produce an emulsion. Suitable solvents for use in EWs include vegetable oils, chlorinated hydrocarbons (such as chlorobenzenes), aromatic solvents (such as alkylbenzenes or alkylnaphthalenes) and other appropriate organic solvents which have a low solubility in water.

Microemulsions (ME) may be prepared by mixing water with a blend of one or more solvents with one or more SFAs, to produce spontaneously a thermodynamically stable isotropic liquid formulation. A compound of Formula (I) is present initially in either the water or the solvent/SFA blend. Suitable solvents for use in MEs include those hereinbefore described for use in in ECs or in EWs. An ME may be either an oil-in-water or a water-in-oil system (which system is present may be determined by conductivity measurements) and may be suitable for mixing water-soluble and oil-soluble pesticides in the same formulation. An ME is suitable for dilution into water, either remaining as a microemulsion or forming a conventional oil-in-water emulsion.

Suspension concentrates (SC) may comprise aqueous or non-aqueous suspensions of finely divided insoluble solid particles of a compound of Formula (I). SCs may be prepared by ball or bead milling the solid compound of Formula (I) in a suitable medium, optionally with one or more dispersing agents, to produce a fine particle suspension of the compound. One or more wetting agents may be included in the composition and a suspending agent may be included to reduce the rate at which the particles settle. Alternatively, a compound of Formula (I) may be dry milled and added to water, containing agents hereinbefore described, to produce the desired end product.

Aerosol formulations comprise a compound of Formula (I) and a suitable propellant (for example w-butane). A compound of Formula (I) may also be dissolved or dispersed in a suitable medium (for example water or a water miscible liquid, such as /?-propanol) to provide compositions for use in non-pressurised, hand-actuated spray pumps.

Capsule suspensions (CS) may be prepared in a manner similar to the preparation of EW formulations but with an additional polymerisation stage such that an aqueous dispersion of oil droplets is obtained, in which each oil droplet is encapsulated by a polymeric shell and contains a compound of Formula (I) and, optionally, a carrier or diluent therefor. The polymeric shell may be produced by either an interfacial polycondensation reaction or by a coacervation procedure. The compositions may provide for controlled release of the compound of Formula (I) and they may be used for seed treatment. A compound of Formula (I) may also be formulated in a biodegradable polymeric matrix to provide a slow, controlled release of the compound.

The composition may include one or more additives to improve the biological performance of the composition, for example by improving wetting, retention or distribution on surfaces; resistance to rain on treated surfaces; or uptake or mobility of a compound of Formula (I). Such additives include surface active agents (SFAs), spray additives based on oils, for example certain mineral oils or natural plant oils (such as soy bean and rape seed oil), and blends of these with other bio-enhancing adjuvants (ingredients which may aid or modify the action of a compound of Formula (I).

Wetting agents, dispersing agents and emulsifying agents may be SFAs of the cationic, anionic, amphoteric or non-ionic type.

Suitable SFAs of the cationic type include quaternary ammonium compounds (for example cetyltrimethyl ammonium bromide), imidazolines and amine salts.

Suitable anionic SFAs include alkali metals salts of fatty acids, salts of aliphatic monoesters of sulphuric acid (for example sodium lauryl sulphate), salts of sulphonated aromatic compounds (for example sodium dodecylbenzenesulphonate, calcium dodecylbenzenesulphonate, butylnaphthalene sulphonate and mixtures of sodium di-Aopropyl- and tri-Aopropyl -naphthalene sulphonates), ether sulphates, alcohol ether sulphates (for example sodium laureth-3 -sulphate), ether carboxylates (for example sodium laureth-3-carboxylate), phosphate esters (products from the reaction between one or more fatty alcohols and phosphoric acid (predominately mono-esters) or phosphorus pentoxide (predominately di-esters), for example the reaction between lauryl alcohol and tetraphosphoric acid; additionally these products may be ethoxylated), sulphosuccinamates, paraffin or olefine sulphonates, taurates and lignosulphonates.

Suitable SFAs of the amphoteric type include betaines, propionates and glycinates.

Suitable SFAs of the non-ionic type include condensation products of alkylene oxides, such as ethylene oxide, propylene oxide, butylene oxide or mixtures thereof, with fatty alcohols (such as oleyl alcohol or cetyl alcohol) or with alkylphenols (such as octylphenol, nonylphenol or octylcresol); partial esters derived from long chain fatty acids or hexitol anhydrides; condensation products of said partial esters with ethylene oxide; block polymers (comprising ethylene oxide and propylene oxide); alkanolamides; simple esters (for example fatty acid polyethylene glycol esters); amine oxides (for example lauryl dimethyl amine oxide); and lecithins.

Suitable suspending agents include hydrophilic colloids (such as polysaccharides, polyvinylpyrrolidone or sodium carboxymethylcellulose) and swelling clays (such as bentonite or attapulgite).

The herbicidal 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, bensulfuron (including bensulfuron-methyl), bentazone, bicyclopyrone, bilanafos, 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, diquat dibromide, diuron, epyrifenacil, ethalfluralin, ethofumesate, fenoxaprop (including fenoxaprop-P- ethyl), fenoxasulfone, 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 the ammonium salt thereof), glyphosate (including the diammonium, isopropylammonium and potassium salts thereof), halauxifen (including halauxifen-methyl), haloxyfop (including haloxyfop-methyl), hexazinone, hydantocidin, 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), 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, 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-l-methoxy-5-methyl-3-[4-(trifluoromethyl)-2-pyridyl]imidazolidin-2-one, 4- hydroxy-l,5-dimethyl-3-[4-(trifluoromethyl)-2-pyridyl]imidazolidin-2-one, 5 -ethoxy -4-hydroxy- l-methyl-3-[4-(trifluoromethyl)-2-pyridyl]imidazolidin-2-one, 4-hydroxy-l-methyl-3-[4- (trifluoromethyl)-2-pyridyl]imidazolidin-2-one, 4-hydroxy-l ,5-dimethyl-3-[l -methyl-5-

(trifluoromethyl)pyrazol-3-yl]imidazolidin-2-one, (4R)l-(5-tert-butylisoxazol-3-yl)-4-ethoxy-5- hydroxy-3-methyl-imidazolidin-2-one, 3-[2-(3,4-dimethoxyphenyl)-6-methyl-3-oxo-pyridazine- 4-carbonyl]bicyclo[3.2. l]octane-2, 4-dione, 2-[2-(3,4-dimethoxyphenyl)-6-methyl-3-oxo- pyridazine-4-carbonyl]-5-methyl-cyclohexane-l, 3-dione, 2-[2-(3,4-dimethoxyphenyl)-6-methyl- 3-oxo-pyridazine-4-carbonyl]cyclohexane-l, 3-dione, 2-[2-(3,4-dimethoxyphenyl)-6-methyl-3- oxo-pyridazine-4-carbonyl]-5,5-dimethyl-cyclohexane-l,3-dione, 6-[2-(3,4-dimethoxyphenyl)-6- methyl-3-oxo-pyridazine-4-carbonyl]-2,2,4,4-tetramethyl-cyclohexane-l,3,5-trione, 2-[2-(3,4- dimethoxyphenyl)-6-methyl-3-oxo-pyridazine-4-carbonyl]-5-ethyl-cyclohexane-l, 3-dione, 2-[2- (3,4-dimethoxyphenyl)-6-methyl-3-oxo-pyridazine-4-carbonyl]-4,4,6,6-tetramethyl- cyclohexane- 1,3 -dione, 2-[6-cyclopropyl-2-(3,4-dimethoxyphenyl)-3-oxo-pyridazine-4- carbonyl]-5-methyl-cyclohexane-l, 3-dione, 3-[6-cyclopropyl-2-(3,4-dimethoxyphenyl)-3-oxo- pyridazine-4-carbonyl] bicyclo [3.2.1] octane-2, 4-dione, 2-[6-cyclopropyl-2-(3 ,4- dimethoxyphenyl)-3-oxo-pyridazine-4-carbonyl]-5,5-dimethyl-cyclohexane-l, 3-dione, 6-[6- cyclopropyl-2-(3,4-dimethoxyphenyl)-3-oxo-pyridazine-4-carbonyl]-2,2,4,4-tetramethyl- cyclohexane-1, 3, 5-trione, 2-[6-cyclopropyl-2-(3,4-dimethoxyphenyl)-3-oxo-pyridazine-4- carbonyl] cyclohexane- 1, 3-dione, 4-[2-(3,4-dimethoxyphenyl)-6-methyl-3-oxo-pyridazine-4- carbonyl]-2,2,6,6-tetramethyl-tetrahydropyran-3,5-dione, 4-[6-cyclopropyl-2-(3,4- dimethoxyphenyl)-3-oxo-pyridazine-4-carbonyl]-2,2,6,6-tetramethyl-tetrahydropyran-3,5- dione, 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-lH-indol-6-yl)pyridine-2-carboxylate), 3-ethylsulfanyl-N-(l,3,4-oxadiazol- 2-yl)-5-(trifluoromethyl)-[l,2,4]triazolo[4,3-a]pyridine-8-carboxamide, 3-

(isopropylsulfanylmethyl)-N-(5-methyl-l,3,4-oxadiazol-2-yl)-5-(trifluoromethyl)- [l,2,4]triazolo[4,3-a]pyridine-8-carboxamide, 3-(isopropylsulfonylmethyl)-N-(5-methyl-l,3,4- oxadiazol-2-yl)-5-(trifluoromethyl)-[l,2,4]triazolo[4,3-a]pyridine-8-carboxamide, 3-

(ethylsulfonylmethyl)-N-(5-methyl-l,3,4-oxadiazol-2-yl)-5-(trifluoromethyl)-[l,2,4]triazolo[4,3- a]pyridine-8-carboxamide and ethyl 2-[[3-[[3-chloro-5-fhroro-6-[3-methyl-2,6-dioxo-4-

(trifhioromethyl)pyrimidin-l-yl] -2 -pyridyl] oxy] acetate.

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, Sixteenth Edition, British Crop Protection Council, 2012.

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).

The compounds or mixtures of the present invention can also be used in combination with one or more herbicide safeners. Examples of such safeners include benoxacor, cloquintocet (including cloquintocet-mexyl), cyprosulfamide, dichlormid, fenchlorazole (including fenchlorazole-ethyl), fenclorim, fluxofenim, furilazole, isoxadifen (including isoxadifen-ethyl), mefenpyr (including mefenpyr-diethyl), metcamifen and oxabetrinil. Particularly preferred are mixtures of a compound of Formula I with cyprosulfamide, isoxadifen-ethyl, cloquintocet-mexyl and/or metcamifen.

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, 16^th Edition (BCPC), 2012. 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 present invention still further provides a method of controlling weeds at a locus said method comprising application to the locus of a weed controlling amount of a composition comprising a compound of Formula (I). Moreover, the present invention further provides a method of selectively controlling weeds at a locus comprising crop plants and weeds, wherein the method comprises application to the locus of a weed controlling amount of a composition according to the present invention. ‘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. Some crop plants may be inherently tolerant to herbicidal effects of compounds of Formula (I). However, in some instances tolerance may need to be engineered into the crop plant, for example by way of genetic engineering. Thus, it is possible that the crop plant is rendered tolerant to HPPD-inhibitors via genetic engineering. Methods of rending crop plants tolerant to HPPD-inhibitors are known, for example from WO0246387. Thus in an even more preferred embodiment the crop plant is transgenic in respect of a polynucleotide comprising a DNA sequence which encodes an HPPD-inhibitor resistant HPPD enzyme derived from a bacterium, more particularly from Pseudomonas fluorescens or Shewanella colwelliana, or from a plant, more particularly, derived from a monocot plant or, yet more particularly, from a barley, maize, wheat, rice, Brachiaria, Cenchrus, Lolium, Festuca, Setaria, Eleusine, Sorghum or Avena species. Several HPPD-tolerant soybean transgenic “events” are known and include for example SYHT04R (WO2012/082542), SYHT0H2 (WO2012/082548) and FG72. Other polynucleotide sequences that can be used to provide plants which are tolerant to the compounds of the present invention are disclosed in, for example, W02010/085705 and WO2011/068567. Crop plants in which the composition according to the invention can be used thus 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.

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- or post-emergence; seed dressing; 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.

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.

Crop plants are to be understood as also including those crop plants 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®. Crop plants 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® andProtexcta®. 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.

Crop plants 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.

The compositions can be used to control unwanted plants (collectively, ‘weeds’). The weeds to be controlled may be both monocotyledonous species, for example Agrostis, Alopecurus, Avena, Brachiaria, Bromus, Cenchrus, Cyperus, Digitaria, Echinochloa, Eleusine, Lolium, Monochoria, Rottboellia, Sagittaria, Scirpus, Setaria and Sorghum, and dicotyledonous species, for example Abutilon, Amaranthus, Ambrosia, Chenopodium, Chrysanthemum, Conyza, Galium, Ipomoea, Nasturtium, Sida, Sinapis, Solanum, Stellaria, Veronica, Viola and Xanthium. Weeds can also include plants which may be considered crop plants but which are growing outside a crop area (‘escapes’), or which grow from seed left over from a previous planting of a different crop (‘volunteers’). Such volunteers or escapes may be tolerant to certain other herbicides.

The compounds of the present invention can be prepared according to the following schemes. Compounds of formula (I) may be prepared from acids of formula (II) and amines of formula (III).

Following the above scheme, the benzoic acid of Formula (II) and the amine of Formula (III) are treated with a suitable amide coupling reagent in a suitable solvent. An additive to increase the reaction rate may optionally be added. An example of a suitable amide coupling reagent is thionyl chloride. An example of a suitable solvent is pyridine. An example of a suitable additive is N- methylimidazole.

Compounds of formula (II) may be prepared from compounds of formula (IV), where “Aik” is defined as a Ci-Ce alkyl group.

The compound of formula (IV) is treated with a hydroxide base, for example sodium hydroxide, in a suitable solvent, for example 3:1 ethanol: water, to give the compound of formula (II).

Compounds of formula (IV) where R² is not chloro may be prepared from compounds of formula (IV) where R² is chloro.

The reagents to convert compounds of formula (IV) where R² is chloro to the compound of formula (IV) where R² is not chloro will vary depending on the nature of R² and will be familiar to the skilled person. For example, a compound of Formula (VII) where R² = chloro may be treated with [1,3 -bis(2,6-diisopropy lphenyl)imidazol-2-ylidene] (3 -chloropyridy l)palladium(II) di chloride, trimethyl boroxine and potassium carbonate, in a suitable solvent, for example 1,4-di oxane, to give the corresponding compound of Formula (VII) where R² = methyl.

Compounds of formula (IV) where R² is chloro may be prepared from carboxylic acids of formula (V) and amines of formula (VI).

The carboxylic acid of formula (V) and the amine of formula (VI) are treated with a suitable amide coupling reagent, for example l-ethyl-3-(3-dimethylaminopropyl)carbodiimide in a suitable solvent, for example dichloromethane.

Compounds of formula (V) where Z = -CH2CH2- may be prepared from compounds of formula (VII)

According to the above stream, the compound of formula (VII) is treated with hydrogen gas and a suitable catalyst, for example palladium on carbon. Compounds of formula (VII) may be prepared from compounds of formula (VIII)

The compound of formula (VIII) is treated with benzyl 2-dimethoxyphosphorylacetate, lithium chloride and l,8-diazabicyclo[5.4.0]undec-7-ene to give the compound of formula (VII).

Aldehydes of formula (VIII) may be prepared alcohols of formula (IX).

The alcohol of formula (IX) is treated with an oxidant, for example Dess-Martin Periodinane, in a suitable solvent, for example benzotrifluoride, to give the compound of formula (VIII). Compounds of formula (IX) may be prepared by carbonylation of aryl bromides of formula (X).

The compound of formula (X) is treated in an autoclave with carbon monoxide gas at a suitable pressure, for example 10 bar, with a suitable catalyst, for example [1,1'- bis(diphenylphosphino)ferrocene]dichloropalladium(II) and a suitable base, for example triethylamine. The solvent is Alk-OH. For example, if the solvent is methanol, “Aik” as shown in the scheme above will be methyl.

Compounds of formula (X) may be prepared from compounds of formula (XI).

The compound of formula (XI) is treated with a reducing agent, for example sodium borohydride, in a suitable solvent, for example methanol.

Compounds of formula (XI) may be prepared from different methods depending on the nature of R³. The skilled person will be able to recognize which method is required. As one example, if R³ is trifluoromethyl, compounds of formula (X) may be prepared from commercially available 1- bromo-2-chloro-4-(trifluoromethoxy)benzene.

l-Bromo-2-chloro-4-(trifluoromethoxy)benzene is treated with a base, for example lithium diisopropylamide, in a suitable solvent, for example tetrahydrofuran. Then, N,N- dimethylformamide is added to the reaction to give the compound of formula (XI).

If R3 is not trifluoromethyl, the compound of formula (X) may be prepared from commercially available 5-bromo-6-chloro-2-hydroxybenzaldehyde.

5-bromo-6-chloro-2-hydroxybenzaldehyde is treated with a reagent which will depend on the nature of R³. The skilled person will be familiar with these reagents and which correspond to which R³. For example, if R³ is difluoromethyl, an example of a suitable reagent is diethyl (bromodifluoromethyl)phosphonate.

Compounds of formula (V) where Z = -CH2- may be prepared from compounds of formula (XII)

The compound of formula (XII) is treated with trifluoroacetic acid and water to give the compound of formula (V) where Z = -CH2-.

Compounds of formula (XII) may be prepared from compounds of formula (XIII).

The compound of formula (XIII) is treated with N-formylsaccharine and a suitable palladium catalyst, for example palladium(II) acetate, and a suitable ligand, for example XantPhos, to give the compound of formula (XII).

Compounds of formula (XIII) may be prepared from compound of formula (XIV)

The compound of formula (XIV) is treated with di-tert-butyl dicarbonate and 4-

(dimethylamino)pyridine to give the compound of formula (XIII).

Compounds of formula (XIV) may be prepared from formula (XV)

The compound of formula (XV) is treated with potassium permanganate in a solvent mixture of acetic acid and water to give the compound of formula (XIV).

Compounds of formula (XV) may be prepared from compounds of formula (XVI).

The compound of formula (XVI) is treated with lithium diisopropylamide and allyl chloride.

Compounds of formula (XVI) may be commercially available, for example where R3 is trifluoromethyl, or they may be prepared from 3-chloro-4-bromophenol.

The method used will depend on the nature of R³. The skilled person will be familiar with these reagents and which correspond to which R³. For example, if R³ is difluoromethyl, an example of a suitable reagent is diethyl (bromodifluoromethyl)phosphonate. According to the present invention there is further provided a compound of Formula (II)

wherein R², R³, R⁴ and R⁵ are as defined in the compound of Formula (I).

According to the present invention there is further provided a compound of Formula (IV)

wherein “Aik” is Ci-Ce alkyl and R², R³, R⁴ and R⁵ are as defined in the compound of Formula (I).

The following non-limiting examples provide specific synthesis methods for representative compounds of the present invention, as referred to the Table(s) provided herein.

Example 1: Preparation of 2-chloro-3-[2-(dimethylamino)-2-oxo-ethyl]-N-(l-methyltetrazol- 5-yl)-4-(trifluoromethoxy)benzamide (Compound 1.001).

Step 1: Preparation of 3-allyl-l-bromo-2-chloro-4-(trifluoromethoxy)benzene

To a solution of diisopropylamine (9.22 mL, 65.3 mmol, 1.2 eq.) in anhydrous tetrahydrofuran (188 mL) under an atmosphere of nitrogen at -78 °C was added dropwise w-butyllithium solution (2.5 M in hexanes, 26.2 mL, 65.3 mmol, 1.2 eq.), maintaining the reaction temperature below - 70 °C. The mixture was stirred at -78 °C for a further 25 minutes. l-bromo-2-chloro-4- (trifluoromethoxy)benzene (15.0 g, 54.5 mmol, 1.0 eq.) was then added dropwise, and the reaction mixture was allowed to stir at -78 °C for one hour. Allyl bromide (9.4 mL, 108 mmol, 2.0 eq.) was added dropwise and the mixture was stirred at -78 °C for a further 30 minutes. The mixture was allowed to warm to room temperature and was then added to sat. aq. NH4CI solution (300 mL). After 2 minutes, this mixture was transferred to a separating funnel, rinsing with further sat. aq. NH4CI solution (50 mL). EtOAc (400 mL) was added and the phases were separated. The aqueous phase was extracted with EtOAc (2 x 500 mL). The combined organic phases were washed with brine (200 mL), dried (MgSO4) and filtered. Silica (60 g) was added to the filtrate and the solvent was removed under reduced pressure. The crude product was purified by reverse phase flash chromatography (acetonitrile+0.1% formic acid/water+0.1% formic acid gradient 70:30 to 100:0). Product-containing fractions were combined and the mixture was partially concentrated in vacuo to remove acetonitrile. The mixture was extracted with EtOAc (3 x 400 mL). The organic layers were combined, washed with brine, dried (MgSC ) and filtered. The solvent was removed under reduced pressure yielding 3-allyl-l-bromo-2-chloro-4-(trifluoromethoxy)benzene (10.8 g, 34.2 mmol, 63%) as a yellow oil. ^JH NMR (400 MHz, methanol-d4) 5 ppm 7.70 (d, 1H), 7.20 - 7.27 (m, 1H), 5.79 - 5.93 (m, 1H), 5.07 (dq, 1H) 4.97 (dq, 1H) 3.65 (dt, 2H).

Step 2: Preparation of 2-[3-bromo-2-chloro-6-(trifluoromethoxy)phenyl]acetic acid

To 3-allyl-l-bromo-2-chloro-4-(trifluoromethoxy)benzene (2.95 g, 9.35 mmol) in acetic acid (44 mL) and water (8.9 mL) at 2-3 °C (ice- water bath) was added portion wise potassium permanganate (4.43 g, 28.1 mmol) over 20 minutes. The mixture was stirred at 2-3 °C for a further 2 hours. The mixture was then quenched into 10% aq sodium metabisulfite solution (100 mL). The reaction flask was washed with EtOAc (2 x 25 mL) and the washings were added to the metabisulfite solution. The mixture was then added to a separating funnel with ethyl acetate (150 mL). The phases were separated. The organic phase was concentrated under reduced pressure yielding a colourless oil. This oil was dissolved in 1 M aq. NaOH solution (150 mL) and washed with EtOAc (2 x 150 mL). The aqueous phase was then acidified with 2 M aq. HC1 (100 mL). The mixture was diluted with ethyl acetate (150 mL) and added to a separating funnel. The phases were separated. The aqueous phase was further extracted with ethyl acetate (20 mL). The combined organic phases were washed with brine, dried (MgSO4), filtered and adsorbed onto C18-silica. The crude product was purified by reverse phase flash chromatography (acetonitrile+0.1 % formic acid/water+0.1% formic acid gradient 50:50 to 100:0). Product-containing fractions were combined, partially concentrated in vacuo to remove acetonitrile and lyophilised to afford 2-[3-bromo-2-chloro-6- (trifluoromethoxy)phenyl]acetic acid (2.12 g, 6.34 mmol, 68%) as a white solid. 'H NMR (400 MHz, chloroform-d) 5 ppm 7.65 (d, 1H) 7.13 (dq, 1H) 4.00 (s, 2H).

Step 3: Preparation of tert-butyl 2-[3-bromo-2-chloro-6-(trifluoromethoxy)phenyl]acetate

To 2-[3-bromo-2-chloro-6-(trifhioromethoxy)phenyl]acetic acid (8.38 g, 25.1 mmol), di-tert-butyl dicarbonate (8.23 g, 37.7 mmol) and 4-(dimethylamino)pyridine (461 mg, 3.77 mmol) under an atmosphere of nitrogen was added tert-butanol (75 mL). The reaction mixture was heated to 70 °C for 3.5 hours. The reaction mixture was cooled to room temperature and added portionwise to 2 M aq. HC1 solution (200 mL) at 0 °C with a stream of nitrogen across the top of the solution to dilute the isobutene formed during the workup. The reaction flask was washed with 2 M aq. HC1 (50 mL) and this washing was added to the quenched mixture. The mixture was transferred to a separating funnel and extracted with ethyl acetate (2 x 100 mL). The combined organic phases were washed with brine, dried (MgSCU) and filtered. Silica (30 g) was added to the filtrate and the solvent was removed under reduced pressure. The crude product was purified by reverse phase flash chromatography (acetonitrile+0.1 % formic acid/water+0.1% formic acid gradient 80:20 to 100:0). Product-containing fractions were combined, partially concentrated in vacuo to remove acetonitrile and lyophilised to afford tert-butyl 2-[3-bromo-2-chloro-6- (trifhioromethoxy)phenyl]acetate (6.87 g, 17.6 mmol, 70%) as an orange-red oil. ^JH NMR (400 MHz, methanol-d4) 5 ppm 7.76 (d, 1H), 7.27 (dq, 1H), 3.88 (s, 2H), 1.43 (s, 9H).

Step 4: Preparation of 3-(2-/e/7-butoxy-2-oxo-ethyl)-2-chloro-4-(trifluoromethoxy)benzoic acid To a vessel containing NMP (10 mL) was added palladium(II) acetate (40 mg, 0.18 mmol), XantPhos (214 mg, 0.359 mmol), N-formylsaccharine (853 mg, 4.04 mmol) and tert-butyl 2-[3- bromo-2-chloro-6-(trifluoromethoxy)phenyl]acetate (700 mg, 1.80 mmol). To a second vessel was added triethylamine (1.13 mL, 8.09 mmol), NMP (10 mL) and water (1.17 mL). The reaction was carried out in a Uniqsis FlowSyn. The two solutions were pumped through a T-piece and then round a 20 mL stainless steel coil heated to 170 oC. The flow rate was set so that the total residence time was 15 min. The reaction mixture was cooled to room temperature and diluted with 2 M aq. HC1 (100 mL) and EtOAc (150 mL). The phases were separated. The aqueous was extracted with EtOAc (100 mL x 2). The combined organic phases were concentrated under reduced pressure and the residue was adsorbed onto reversed phase silica (4.5 g). The crude product was partially purified by reverse phase flash chromatography (acetonitrile+0.1 % formic acid/water+0.1% formic acid gradient 10:90 to 70:30). Product-containing fractions were combined and partially concentrated in vacuo to remove acetonitrile. The mixture was basified by addition of sat. aq. NaHCO, solution (400 mL) and was washed with EtOAc. The organic phase was extracted with further sat. aq. NaHCO-, solution (100 mL). The aqueous phases were combined and acidified with cone. HC1 (ca. 20 mL) until pH < 3. The aqueous phase was then extracted with EtOAc (3 x 150 mL). The combined organic phases were washed with brine (100 mL), dried (MgSO4) and filtered. The filtrate was adsorbed onto reversed phase silica (5 g). The partially purified material was further purified by reverse phase flash chromatography (acetonitrile+0.1 % formic acid/water+0.1% formic acid gradient 50:50 to 80:20). Product-containing fractions were combined and partially concentrated in vacuo to remove acetonitrile. The aqueous phase was extracted with ethyl acetate (3 x 150 mL). The combined organic phases were washed with brine, dried (MgSC ) and filtered. The solvent was removed under reduced pressure and the sample was further dried under high-vacuum to afford 3-(2-/ /7-butoxy-2-oxo-ethyl)-2-chloro-4- (trifluoromethoxy)benzoic acid (203 mg, 0.572 mmol, 32%) as a white solid.

NMR (400 MHz, chloroform-d) 5 ppm 7.99 (d, 1H), 7.30 (dq, 1H), 3.90 (s, 2H), 1.45 (s, 9H).

Step 5: Preparation of tert-butyl 2-[2-chloro-3-[(l-methyltetrazol-5-yl)carbamoyl]-6- (trifluoromethoxy)phenyl]acetate

To 3-(2-tert-butoxy-2-oxo-ethyl)-2-chloro-4-(trifluoromethoxy)benzoic acid (1.85 g, 5.22 mmol) was added pyridine (37 mL), 1 -methylimidazole (0.416 mL, 5.22 mmol), triethylamine (1.090 mL, 7.82 mmol) and l-methyltetrazol-5-amine (775 mg, 7.82 mmol). The resulting solution was sparged with nitrogen for 5 minutes. The solution was then cooled to ~5 °C using a ice-water bath and thionyl chloride (0.757 mL, 10.4 mmol) was added dropwise over 10 minutes. The mixture was stirred at ~5 °C for 1.5 hours then at room temperature for a further 16 hours. The reaction was then quenched into 2 M aq. HC1 (200 mL) portionwise. The mixture was extracted with ethyl acetate (3 x 250 mL). The organic phase was washed with brine (150 mL), dried (MgSCL) and filtered. The filtrate was adsorbed onto silica. The compound was partially purified by flash column chromatography (EtOAc/cyclohexane gradient 30:70 to 50:50) Product containing fractions were combined and the solvent was removed under reduced pressure to afford a yellow oil. This partially purified material was adsorbed onto C18-silica (8 g) using acetone (100 mL). The partially purified material was further purified by reversed phase flash chromatography (acetonitrile+0.1% formic acid/water+0.1% formic acid gradient 45:55 to 70:30). Productcontaining fractions were combined and partially concentrated in vacuo to remove acetonitrile. The mixture was then extracted with ethyl acetate (3 x 150 mL). The combined organic phases were washed with brine (150 mL), dried (MgSCU) and filtered. The solvent was removed from the filtrate under reduced pressure and the sample was further dried under high-vacuum overnight affording /crz-butyl 2-[2-chloro-3-[(l -methyltetrazol-5-yl)carbamoyl]-6-

(trifhioromethoxy)phenyl]acetate (1.46 g, 3.36 mmol, 64%) as an off white solid. 'H NMR (400 MHz, methanol-d4) 5 ppm 7.75 (d, 1H), 7.45 - 7.54 (m, 1H), 4.07 (s, 3H), 3.92 (s, 2H), 1.45 (s, 9H).

Step 6: Preparation of 2-[2-chloro-3-[(l-methyltetrazol-5-yl)carbamoyl]-6-

(trifluoromethoxy)phenyl]acetic acid

To tert-butyl 2-[2-chloro-3-[(l -methyltetrazol-5-yl)carbamoyl]-6-

(trifluoromethoxy)phenyl]acetate (1.18 g, 2.70 mmol) was added trifluoroacetic acid (14 mb) and water (7 mL). The mixture was stirred at room temperature for 3.5 hours. The reaction mixture was then diluted with water. The organic solvent was removed under reduced pressure and water was removed via freeze drying. The crude product was adsorbed onto C18-silica and purified via reversed phase flash chromatography (acetonitrile+0.1 % formic acid/water+0.1% formic acid gradient 20:80 to 40:60). Product-containing fractions were combined and partially concentrated in vacuo to remove acetonitrile. The mixture was then extracted with ethyl acetate (3 x 150 mL). The combined organic phases were washed with brine (150 mL), dried (MgSCU) and filtered. The solvent was removed from the filtrate under reduced pressure and the sample was further dried under high-vacuum overnight to afford 2-[2-chloro-3-[(l-methyltetrazol-5-yl)carbamoyl]-6- (trifluoromethoxy)phenyl] acetic acid (852 mg, 2.24 mmol, 83%) as a white solid. 'H NMR (400 MHz, methanol-d4) 5 ppm 7.74 (d, 1H), 7.46 - 7.53 (m, 1H), 4.07 (s, 3H), 3.97 (s, 2H).

Step 7: Preparation of 2-chloro-3-[2-(dimethylamino)-2-oxo-ethyl]-N-(l-methyltetrazol-5-yl)-4- (trifluoromethoxy)benzamide

To a solution of 2-[2-chloro-3-[(l-methyltetrazol-5-yl)carbamoyl]-6- (trifhioromethoxy)phenyl]acetic acid (120 mg, 0.316 mmol), 3-(ethyliminomethyleneamino)- N,N-dimethyl-propan-l -amine hydrochloride (72.7 mg, 0.379 mmol), 4-(dimethylamino)pyridine (3.8 mg, 0.032 mmol) in anhydrous di chloromethane (3.6 mL) was added dimethylamine solution (5.6 M in ethanol, 0.11 mL). The mixture was stirred at room temperature for 5 hours. The reaction was quenched by the addition of 2 M aq. HC1 (20 mL). The organic solvent was removed under reduced pressure. The aqueous phase was extracted with EtOAc (2 x 30 mL). The combined organic phases were washed with brine (40 mL), dried (MgSCL) and filtered. The filtrate was adsorbed onto Cl 8-silica. The crude product was purified via reversed phase flash chromatography (acetonitrile+0.1% formic acid/water+0.1% formic acid gradient 20:80 to 40:60). Product- containing fractions were combined and partially concentrated in vacuo to remove acetonitrile, then the mixture was lyophilised to afford 2-chloro-3-[2-(dimethylamino)-2-oxo-ethyl]-N-(l- methyhetrazol-5-yl)-4-(trifhioromethoxy)benzamide (40 mg, 0.098 mmol, 31%) as a yellow oil. ¹ H NMR (400 MHz, methanol-d4) 5 7.72 (d, 1H), 7.48 (m, 1H), 4.11 - 4.04 (m, 5H), 3.24 (s, 3H), 2.99 (s, 3H)

Example 2: Preparation of 2-chloro-3-[3-(dimethylamino)-3-oxo-propyl]-N-(l- methyltetrazol-5-yl)-4-(trifluoromethoxy)benzamide (Compound 1.005)

Step 1: Preparation of Methyl 3-[(E)-3-benzyloxy-3-oxo-prop-l-enyl]-2-chloro-4-

(trifluoromethoxy)benzoate

To a 3 -necked flask, equipped with a thermometer, containing anhydrous acetonitrile (40mL) was added dry lithium chloride (0.18 g, 4.25mmol), benzyl 2-dimethoxyphosphorylacetate (1.1g, 4.25 mmol), l,8-diazabicyclo[5.4.0]undec-7-ene (3.54 mmol) and methyl 2-chloro-3-formyl-4- (trifluoromethoxy)benzoate (1 g, 3.54 mmol). The reaction mixture was stirred overnight at room temperature. The reaction is cooled to 0 °C using a dry ice/acetone bath quenched by the dropwise addition of saturated NaHCO, solution. This was extracted with ethyl acetate x 3 and the organics were collected and reduced in vacuo to afford methyl 3-[(E)-3-benzyloxy-3-oxo-prop-l-enyl]-2- chloro-4-(trifluoromethoxy)benzoate (1.55 g, 3.74 mmol) as a yellow gum. 1H NMR (400 MHz, chloroform) 5 = 7.90 - 7.80 (m, 1H), 7.80 - 7.72 (m, 1H), 7.45 - 7.27 (m, 7H), 7.46 - 7.27 (m, 7H), 6.63 - 6.54 (m, 1H), 4.00 - 3.91 (m, 3H)

Step 2: Preparation of 3-[2-chloro-3-methoxycarbonyl-6-(trifluoromethoxy)phenyl]propanoic acid

Reaction carried out in SyTracks COware vessel fitted with H caps.Pd/C (50% wet) (0.05 mmol, 0.2 g) was added into chamber B of the COware vessel, followed by addition of a solution of methyl 3-[(E)-3-benzyloxy-3-oxo-prop-l-enyl]-2-chloro-4-(trifluoromethoxy)benzoate (1.5 g, 3.6 mmol) in 10 mL Ethyl Acetate. A stirrer bar was added & Chamber B was sealed using an H-cap. Granular zinc, 20 mesh (1.52g, 23.3 mmol) was added into chamber A of the COware vessel and the vessel was placed behind a blast shield. 2ml 6M HC1 was added by syringe to chamber A, chamber A was then sealed with an H-cap. Reaction stirred at room temperature behind a blast shield for 10 days. Contents of chamber B are filtered through a small plug of celite, washing with EtOAc. The filtrate was concentrated under reduced pressure and purified using normal phase column chromatography (0-70% Ethyl Acetate in Cyclohexane). Combined fractions are reduced in vacuo to afford 3-[2-chloro-3-methoxycarbonyl-6-(trifluoromethoxy)phenyl]propanoic acid (630mg, 1.92mmol, 53% yield) as a white solid. 1H NMR (400 MHz, chloroform) 5 = 7.73 - 7.67 (m, 1H), 7.27 - 7.22 (m, 2H), 3.97 - 3.90 (m, 3H), 3.29 - 3.23 (m, 1H), 3.27 - 3.20 (m, 2H), 2.68 - 2.56 (m, 2H)

Step 3: Preparation of Methyl 2-chloro-3-[3-(dimethylamino)-3-oxo-propyl]-4- (trifluoromethoxy)benzoate

To a 5 mL flask under an atmosphere of Nitrogen, was added 3-[2-chloro-3-methoxycarbonyl-6- (trifhioromethoxy)phenyl]propanoic acid (0.315 g, 0.96 mmol), 3-(ethyliminomethyleneamino)-

N,N-dimethyl-propan-l-amine;hydrochloride (0.22g, 1.16 mmol), N,N-dimethylpyridin-4-amine (0.011 g, 0.096 mmol), and dichloromethane (9.45 ml). To the reaction mixture is added dimethylamine (1.2 mL, 2.41 mmol, 2 mol/L), in THF and the reaction was stirred at room temperature overnight. The reaction was quenched by the addition of 2 M HC1 and extracted with ethyl acetate X2. The organic layers were separated, reduced in vacuo and was purified via normal phase column chromatography (0-70% Ethyl Acetate in cyclohexane) to afford Methyl 2-chloro- 3-[3-(dimethylamino)-3-oxo-propyl]-4-(trifluoromethoxy)benzoate as a colourless gum (210 mg,

O.59mmol, 62%). 1H NMR (400 MHz, chloroform) 5 = 7.71 - 7.61 (m, 1H), 7.26 - 7.16 (m, 1H), 4.01 - 3.85 (m, 3H), 3.30 - 3.17 (m, 2H), 3.03 - 2.92 (m, 6H), 2.58 - 2.46 (m, 2H)

Step 4: Preparation of 2-chloro-3-[3-(dimethylamino)-3-oxo-propyl]-4-(trifluoromethoxy)benzoic acid

To a stirred solution of methyl 2-chloro-3-[3-(dimethylamino)-3-oxo-propyl]-4- (trifluoromethoxy)benzoate (210 mg, 0.59 mmol) in Tetrahydrofuran (2.5 mL) and Methanol (2.5 mL), a solution of lithium hydroxide (43 mg, 1.8 mmol) in water (0.5 mL) was added and the reaction mixture stirred at room temperature for 12 hr. The reaction mass was concentrated in vacuo and the residue diluted with IM HC1 (10ml) and extracted into Ethyl acetate (10ml) X 2. The organics are collected and reduced in vacuo to afford 2-chloro-3-[3-(dimethylamino)-3-oxo- propyl]-4-(trifluoromethoxy)benzoic acid (150mg, 0.42mmol, 71% yield) as a white solid. 1H NMR (400 MHz, chloroform) 5 = 7.85 - 7.77 (m, 1H), 7.25 - 7.20 (m, 1H), 3.29 - 3.21 (m, 2H), 3.02 (d, J = 10.9 Hz, 6H), 2.65 - 2.55 (m, 2H)

Step 5: Preparation of 2-chloro-3-[3-(dimethylamino)-3-oxo-propyl]-N-(l-methyltetrazol-5-yl)-4- (trifluoromethoxy)benzamide (Compound 1.005)

To a 3 neck flask, equipped with a thermometer, containing anhydrous Pyridine (2 mL) (that was purged and filled with N2) was added 2-chloro-3-[3-(dimethylamino)-3-oxo-propyl]-4- (trifluoromethoxy)benzoic acid (A, 150 mg, 0.44mmol) and 1 -methyltetrazol-5 -amine (53 mg, 0.53 mmol). The reaction mixture was stirred at room temperature for 10 min, followed by the addition of 1 -Methylimidazole (0.036 mL, 0.45 mmol). The Reaction was stirred for 30 minutes at room temperature and then cooled to 0°C using a dry ice/acetone bath. Thionyl Chloride (0.065 mL, 0.89 mmol) was added dropwise over 30 mins. The reaction mixture is allowed to warm to room temperature and stirred overnight. The reaction was cooled to 0°C using a dry ice/acetone bath, water (5ml) added and quenched by addition of 11 M HC1 solution. The mixture is transferred to a separating funnel and followed by Ethyl acetate extraction X3. The organic phase was concentrated in vacuo and purified by reverse phase column chromatography (30-70% MeCN in H2O gradient with 0.1% formic acid) to afford 2-chloro-3-[3-(dimethylamino)-3-oxo-propyl]-N- (l-methyltetrazol-5-yl)-4-(trifluoromethoxy)benzamide (25 mg, 0.06 mmol, 14%). lH NMR (d4- methanol) 5: 7.55-7.66 (m, 1H), 7.37-7.45 (m, 1H), 4.02 (s, 3H), 3.14-3.25 (m, 2H), 2.98-3.08 (m, 3H), 2.95 (s, 3H), 2.60-2.69 (m, 2H)

TABLE 1 - Examples of herbicidal compounds of the present invention.

Biological Examples

Seeds of a variety of test species are sown in standard soil in pots (Lolium perenne (LOLPE), Amaranthus retoflexus (AMARE), Amaranthus palmeri (AMAPA), Setaria faberi (SETFA), Echinochloa crus-galli (ECHCG), Ipomoea hederacea (IPOHE)). After cultivation for one day (pre-emergence) or after 8 days cultivation (post-emergence) under controlled conditions in a glasshouse (at 24/16°C, day/night; 14 hours light; 65 % humidity), the plants are sprayed with an aqueous spray solution derived from the formulation of the technical active ingredient in acetone / water (50:50) solution containing 0.5% Tween 20 (poly oxy ethelyene sorbitan mono laurate, CAS RN 9005-64-5). Compounds are applied at 130 g/h unless otherwise indicated. The test plants are then grown in a glasshouse under controlled conditions in a glasshouse (at 24/16°C, day/night; 14 hours light; 65 % humidity) and watered twice daily. After 13 days for pre and post-emergence, the test is evaluated for the percentage damage caused to the plant. The biological activities are shown in the following table on a five-point scale (5 = 80-100%; 4 = 60-79%; 3=40-59%; 2=20- 39%; 7=0-19%).

TABLE Bl

Claims

1. A compound of F ormula (I) :

or an agronomically acceptable salt thereof, wherein: -

R³ is Ci-Cehaloalkyl;

R⁴ is selected from the group consisting of hydrogen, Ci-C4alkyl, Cs-Cecycloalkyl-, Ci- C4haloalkyl, Ci-C4alkoxy-Ci-C4alkyl-, Ci-C4haloalkoxy-Ci-C4alkyl-, aryl or a 5- or 6- membered heteroaryl wherein the aryl or 5- or 6-membered heteroaryl is optionally substituted by one or more substituents independently selected from the group consisting of halogen, C1-C3 alkyl (e.g methyl), Ci-Cshaloalkyl, Ci-Csalkoxy- and -S(O)_pCi-C3alkyl; and R⁵ is selected from the group consisting of hydrogen, Ci-C4alkyl, Cs-Cecycloalkyl-, Ci- C4haloalkyl, Ci-C4alkoxy-Ci-C4alkyl-, Ci-C4haloalkoxy-Ci-C4alkyl-, aryl or a 5- or 6- membered heteroaryl wherein the aryl or 5- or 6-membered heteroaryl is optionally substituted by one or more substituents independently selected from the group consisting of halogen, C1-C3 alkyl (e.g methyl), Ci-Cshaloalkyl, Ci-Csalkoxy- and -S(O)_pCi-C3alkyl; or

Z is -CH2- or -CH2CH2-; and p is independently 0, 1 or 2.

2. A compound according to claim 1, wherein R¹ is selected from the group consisting of methyl, ethyl and n -propyl.

3. A compound according to any one of the previous claims, wherein R² is selected from the group consisting of methyl, Cl, -CF3 and -SO₂methyl.

4. A compound according to claim 3, wherein R² is Cl.

5. A compound according to any one of the previous claims, wherein R³ is -CF3 or -CHF2.

6. A compound according to any one of the previous claims, wherein R⁴ is selected from the group consisting of hydrogen, Ci-Cealkyl-, Ci-C4haloalkoxy-Ci-C4alkyl- and C3- Cecycloalkyl-.

7. A compound according to claim 6, wherein R⁴ is selected from the group consisting of methyl, ethyl, methoxyethyl- and cyclopropyl.

8. A compound according to any one of the previous claims, wherein R⁵ is hydrogen or Ci- C4alkyl-.

9. A compound according to any one of the previous claims wherein R⁴ is selected from the group consisting of methyl, ethyl, methoxyethyl- and cyclopropyl and R⁵ is hydrogen.

10. A compound according to any one of the claims 1 to 5, wherein R⁴ and R⁵ together with the nitrogen atom to which they are attached form a saturated 4-, 5- or 6-membered heterocycle optionally containing one or two additional heteroatoms independently selected from O, N- and S(O)_P.

11. A herbicidal composition comprising a compound according to any one of the previous claims and an agriculturally acceptable formulation adjuvant.

12. A herbicidal composition according to claim 11, further comprising at least one additional pesticide.

13. A herbicidal composition according to claim 12, wherein the additional pesticide is a herbicide or herbicide safener.

14. A method of controlling weeds at a locus comprising application to the locus of a weed controlling amount of a composition according to any one of claims 11 to 13.

15. Use of a compound of Formula (I) as defined in claim 1 as a herbicide.

16. A compound of F ormula (II)

wherein R², R³, R⁴ and R⁵ are as defined in the compound of Formula (I) in any one of claims 1 to 10 above. A compound of Formula (IV)

wherein “Aik” is Ci-Ce alkyl and R², R³, R⁴ and R⁵ are as defined in the compound of Formula (I) in any one of claims 1 to 10 above.