WO2025114014A1 - Herbicidal compounds - Google Patents

Abstract

The application relates to compounds of Formula (I), or an agronomically acceptable salt of said compounds, to herbicidal compositions which comprise a compound of Formula (I) and to the use of compounds of Formula (I) for controlling weeds, in particular in crops of useful plants.

Description

HERBICIDAL COMPOUNDS

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

Herbicidal 3-isoxazolidinones are known from US 4,405,357. Herbicidal isoxazolidine-3, 5-diones are known from US 4,302,238. W02023/020274 describes the 3- isoxazolidinone compound Broclozone and its use as a herbicide. The present invention relates to novel 3-isoxazolidinone and isoxazolidine-3, 5-dione compounds. Thus, according to the present invention there is provided a compound of Formula (I):

or a salt thereof, wherein:

A¹ is CHR¹ or C(O); R¹ is selected from the group consisting of hydrogen, halogen, hydroxy, Ci-Cealkoxy, Ci-Cealkoxy-Ci-Cealkoxy-, Ci-C3alkyl-C(O)O-, HOC(O)Ci-Cealkoxy- , Ci-C6alkoxy-C(O)-Ci-Cealkoxy-, Ci-C3alkyl-S(O)_p- and Ci-C3alkyl-S(O)_pCi-C6alkoxy-; R³ and R⁴ are each independently Ci-Csalkyl; X¹ is O or S; and Q is Q¹ or Q²

wherein the jagged line denotes the point of attachment to the rest of the molecule; X² is bromo or fluoro; R⁵ and R⁶ are each independently selected from the group consisting of hydrogen, halogen, Ci-Cealkyl, Ci-Cehaloalkyl, Cs-Cecycloalkyl and Ci-Cealkoxy-; or R⁵ and R⁶ together are =0 or -(CH2)n-; n is an integer of 2, 3, 4 ,5 or 6; A² and A³ are each independently selected from the group consisting of CR⁷R⁸, C(O), O, S(O)_P and N(R⁹); each R⁷ is independently selected from the group consisting of hydrogen, halogen, Ci-Cealkyl, Ci-Cehaloalkyl, Cs-Cecycloalkyl and Ci-Cealkoxy-; and each R⁸ is independently selected from the group consisting of hydrogen, halogen, Ci- Cealkyl, Ci-Cehaloalkyl, Cs-Cecycloalkyl and Ci-Cealkoxy-; or R⁷ and R⁸ together with the carbon atom to which they are bonded form a 3- to 7-membered carbocyclic ring; each R⁹ is hydrogen or Ci-Csalkyl; A⁵, A⁶ and A⁷ are each independently selected from the group consisting of C(R¹⁰), N(R¹¹)_q, S and O, each q is an integer or 0 or 1 ; each R¹⁰ is independently selected from the group consisting of hydrogen, halogen, Ci-Csalkyl, aryl, Ci-Cshaloalkyl, Ci-Cshaloalkoxy-, Ci-Csalkoxy-, and Cs-Cecycloalkyl; each R¹¹ is independently selected from the group consisting of hydrogen, Ci-Csalkyl- and Ci- Cshaloalkyl, and each p is independently an integer of 0, 1 or 2.

In a second aspect there is provided a herbicidal composition comprising a compound of Formula (I) as described herein, and an agriculturally acceptable formulation adjuvant.

In a third aspect the invention provides the use of a compound of Formula (I) or a composition of the invention as a herbicide.

In a third aspect, the invention provides a method of controlling plants, comprising applying to the plants or to the locus of the plants, a herbicidally effective amount of a compound or composition of the invention.

In a fourth aspect, the invention provides a method of inhibiting plant growth, comprising applying to the plants or to the locus thereof, a herbicidally effective amount of a compound or composition of the invention.

In a fifth aspect, the invention provides a method of controlling weeds in crops of useful plants, comprising applying to the weeds or to the locus of the weeds, or to the useful plants or to the locus of the useful plants, a herbicidally effective amount of a compound or composition of the invention.

In a sixth aspect, the invention provides a method of selectively controlling grasses and/or weeds in crops of useful plants which comprises applying to the useful plants or locus thereof or to the area of cultivation a herbicidally effective amount of a compound or composition of the invention.

The term Ci-Cealkyl- includes, for example, methyl (Me, CH3), ethyl (Et, C2H5), n- propyl (n-Pr), isopropyl (/-Pr), n-butyl (n-Bu), isobutyl (/-Bu), sec-butyl and tert-butyl (t-Bu). Ci-Csalkyl includes methyl (Me, CH3), ethyl (Et, C2H5) and propyl (Pr e.g /so-propyl and n- propyl).

Halogen (or halo) includes, for example, 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, dichloromethyl, trichloromethyl, 2,2,2-trifluoroethyl, 2-fluoroethyl, 2- chloroethyl, pentafluoroethyl, 1 , 1-difluoro-2,2,2-trichloroethyl, 2,2,3,3-tetrafluoropropyl and 2,2,2-trichloroethyl and heptafluoro-n-propyl. Ci-C2haloalkyl is, for example, fluoromethyl, difluoromethyl, trifluoromethyl, chloromethyl, dichloromethyl, trichloromethyl, 2,2,2- trifluoroethyl, 2-fluoroethyl, 2-chloroethyl, pentafluoroethyl, or 1 , 1-difluoro-2,2,2- trichloroethyl.

Ci-Cealkoxy includes methoxy, ethoxy and iso-propoxy-.

Ci-Cehaloalkoxy- includes, for example, fluoromethoxy, difluoromethoxy, trifluoromethoxy, 2,2,2-trifluoroethoxy, 1 ,1 ,2,2-tetrafluoroethoxy, 2-fluoroethoxy, 2- chloroethoxy, 2,2-difluoroethoxy or 2,2,2-trichloroethoxy, preferably difluoromethoxy, 2- chloroethoxy or trifluoromethoxy.

Ci-Cealkoxy-Ci-Cealkoxy- includes for example methoxym ethoxy- and ethoxymethoxy-.

Ci-C3alkyl-C(O)O- includes methyl-C(O)O- and ethyl-C(O)O-.

Ci-C6alkoxy-C(O)-Ci-Cealkoxy- includes methoxy-C(O)-methoxy- and ethoxy-C(O)- m ethoxy-.

Ci-C3alkyl-S(O)_pCi-C6alkoxy- includes methyl-S(O)_pmethoxy- and ethyl- S(O)_pmethoxy-.

Cs-Cecycloalkyl includes cyclopropyl, cyclopentyl and cyclohexyl.

Ci-C4alkyl-S- (alkylthio) includes, for example, methylthio, ethylthio, propylthio, isopropylthio, n-butylthio, isobutylthio, sec-butylthio or tert-butylthio, preferably methylthio or ethylthio.

Ci-C4alkyl-S(O)- (alkylsulfinyl) includes, for example, methylsulfinyl, ethylsulfinyl, propylsulfinyl, isopropylsulfinyl, n-butylsulfinyl, isobutylsulfinyl, sec-butylsulfinyl or tertbutylsulfinyl, preferably methylsulfinyl or ethylsulfinyl.

Ci-C4alkyl-S(O)2- (alkylsulfonyl) includes, for example, methylsulfonyl, ethylsulfonyl, propylsulfonyl, isopropylsulfonyl, n-butylsulfonyl, isobutylsulfonyl, sec-butylsulfonyl or tertbutylsulfonyl, preferably methylsulfonyl or ethylsulfonyl.

The term aryl as used herein includes phenyl, tolyl, xylyl, and naphthyl, but preferably refers to phenyl. Preferred values of A¹, Q, X¹, R¹, R³, R⁴, and p, as well as of the substituents comprised within these moieties (i.e. Q¹, Q², A², A³, A⁵ A⁶ A⁷, X², R⁵, R⁶, R⁷, R⁸, R⁹, R¹⁰, R¹¹, and n) and a compound of formula (I) according to, and for use in, the invention may comprise any combination of said values. The skilled man will appreciate that values for any specified set of embodiments may combined with values for any other set of embodiments where such combinations are not mutually exclusive.

As stated herein, X¹ may be O or S, however in one set of embodiments it is preferred that X¹ is O.

A¹ is defined as CHR¹or C(O). In embodiments where A¹ is CHR¹, it is preferred that R¹ is hydrogen, hydroxy, or Ci-Cealkoxy. Such embodiments may be referred to as compounds of Formula (la)

wherein R³, R⁴ X¹ and Q are as defined herein. In such embodiments it is preferred that R¹ is hydrogen or Ci-Cealkoxy, and it is particularly preferred that R¹ is hydrogen.

In alternative embodiments A¹ is C(O), and such embodiments may be referred to as compounds of Formula (lb)

wherein R³, R⁴ X¹ and Q are as defined herein.

Preferably R³ is methyl or ethyl, more preferably methyl.

Preferably R⁴ is methyl or ethyl, more preferably methyl. In one set of embodiments both R³ and R⁴ are methyl.

In compounds of the invention Q may be Q¹ or Q² as defined supra. The substituent X² is common to both Q moieties (i.e. common to Q¹ and Q²) and is defined as either bromo or fluoro. In both Q moieties it is preferred that X² is bromo. In those embodiments where Q is Q¹,

A² and A³ are each independently selected from the group consisting of CR⁷R⁸, C(O), O, S(O)_P and N(R⁹). Preferably A² and A³ are each independently selected from CR⁷R⁸, C(O), and O. In one set of preferred embodiments A² is O, and A³ is selected from CR⁷R⁸, C(O), and O. In a further set of preferred embodiments A² and A³ are both O.

Preferably R⁵ and R⁶ are independently selected from the group consisting of hydrogen, methyl and fluoro, more preferably from the group consisting of methyl and fluoro. Thus, in one set of embodiments R⁵ and R⁶ are both methyl, whilst in another set of embodiments R⁵ and R⁶ are both fluoro, and in a third set of embodiments R⁵ is methyl and R⁶ or fluoro, or R⁶ is fluoro and R⁵ is methyl.

Each R⁷ is preferably independently selected from the group consisting of hydrogen, halogen, Ci-Csalkyl, Ci-Cshaloalkyl, C3-C4cycloalkyl and Ci-Csalkoxy-. More preferably each R⁷ is independently hydrogen, halogen (preferably chloro or fluoro), methyl, ethyl, n- propyl, c-propyl, Ci-Cshaloalkyl, methoxy or ethoxy. More preferably still, each R⁷ is independently hydrogen or halogen (in particular fluoro).

Each R⁸ is preferably independently selected from the group consisting of hydrogen, halogen, Ci-Csalkyl, Ci-Cshaloalkyl, C3-C4cycloalkyl and Ci-Csalkoxy-. More preferably each R⁷ is independently hydrogen, halogen (preferably chloro or fluoro), methyl, ethyl, n- propyl, c-propyl, Ci-Cshaloalkyl, methoxy or ethoxy.

In one set of embodiments at least one CR⁷R⁸ is CH2.

In a further set of embodiments, R⁷ and R⁸ together with the carbon atom to which they are bonded form a 3- to 7-membered carbocyclic ring. In such embodiments, the carbocyclic ring is preferably formed only at one of A² or A³.

In those embodiments where Q is Q²

A⁵, A⁶ and A⁷ are each independently selected from the group consisting of C(R¹⁰), N(R¹¹)n, S and O; where each R¹⁰ is independently selected from the group consisting of hydrogen, halogen, Ci-Csalkyl, aryl, Ci-Cshaloalkyl, Ci-Cshaloalkoxy-, Ci-Csalkoxy-, and Cs-Cecycloalkyl; and each R¹¹ is independently selected from the group consisting of hydrogen, Ci-Csalkyl- and Ci-Cshaloalkyl.

Preferred sets of embodiments comprise A⁵, A⁶ and A⁷ as follows: (i) A⁵ is O, A⁶ is C(R¹⁰) and A⁷ is N(R¹¹), and (ii) A⁵ is N(R¹¹), A⁶ is N(R¹¹) and A⁷ is N(R¹¹). Preferably each R¹⁰ is selected from hydrogen, Ci-Csalkyl, Cs-Cecyloalkyl, phenyl, benzyl, Ci-Cshaloalkyl, Ci-Cshaloalkoxy-, and Ci-Csalkoxy-. More preferably each R¹⁰ is independently selected from the group consisting of hydrogen, methyl, ethyl, cyclopropyl and difluoromethyl, more preferably from the group consisting of methyl, cyclopropyl and difluoromethyl. In one set of embodiments R¹⁰ is methyl.

Preferably each R¹¹ is independently selected from the group consisting of hydrogen, methyl, ethyl, and cyclopropyl.

Compounds 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 provides agronomically acceptable salts of compounds of Formula (I). Salts that the compounds of Formula (I) may form with amines, including primary, secondary and tertiary amines (for example ammonia, dimethylamine and triethylamine), alkali metal and alkaline earth metal bases, transition metals or quaternary ammonium bases are preferred.

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 (SAA). Thus, the present invention further provides a herbicidal composition comprising a herbicidal compound of Formula (I) as described herein 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. These include an emulsion concentrate (EC), a suspension concentrate (SC), a suspo-emulsion (SE), a capsule suspension (CS), a water dispersible granule (WG), an emulsifiable granule (EG), an emulsion, water in oil (EG), an emulsion, oil in water (EW), a micro-emulsion (ME), an oil dispersion (OD), an oil miscible flowable (OF), an oil miscible liquid (OL), a soluble concentrate (SL), an ultra-low volume suspension (Sil), an ultra-low volume liquid (UL), a technical concentrate (TK), a dispersible concentrate (DC), a soluble powder (SP), a wettable powder (WP) and a soluble granule (SG). 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).

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 SAAs, 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 SAAs, to produce spontaneously a thermodynamically stable isotropic liquid formulation. A compound of Formula (I) is present initially in either the water or the solvent/SAA 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 n-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 n-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 (SAAs), spray additives based on oils, for example certain mineral oils or natural plant oils (such as soy bean and rape seed oil), modified plant oils such as methylated rape seed oil (MRSO), 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 SAAs of the cationic, anionic, amphoteric or non-ionic type. Suitable SAAs of the cationic type include quaternary ammonium compounds (for example cetyltrimethyl ammonium bromide), imidazolines and amine salts.

Suitable anionic SAAs 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- /sopropyl- and tri-/sopropyl-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, lignosulphonates and phosphates I sulphates of tristyrylphenols.

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

Suitable SAAs 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); lecithins and sorbitans and esters thereof, alkyl polyglycosides and tristyrylphenols.

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

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, broclozone, 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), fluchloraminopyr (including fluchloramino- tefuryl), flufenacet, flufenoximacil, flumetsulam, flumioxazin, fluometuron, fomesafen flupyrsulfuron (including flupyrsulfuron-methyl-sodium), fluroxypyr (including fluroxypyr- meptyl), flusulfinam, 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, icafolin (including icafolin-methyl), imazamox (including R-imazamox), imazapic, imazapyr, imazethapyr, indaziflam, indolauxipyr (including indolauxipyr-cyanomethyl), iodosulfuron (including iodosulfuron-methyl-sodium), iofensulfuron (including iofensulfuron-sodium), ioxynil, iptriazopyrid, 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), pyraquinate, pyrasulfotole, pyridate, pyriftalid, pyriflubenzoxim, 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, (1RS,5SR)-3-[2-methoxy-4-(prop-1-yn-1- yl)phenyl]-4-oxobicyclo[3.2.1]oct-2-en-2-yl methyl carbonate, ethyl-2-[[3-[[3-chloro-5- fluoro-6-[3-methyl-2,6-dioxo-4-(trifluoromethyl)pyrimidin-1-yl]-2- pyridyl]oxy]acetate, methyl 2-[2-[2-bromo-4-fluoro-5-[3-methyl-2,6-dioxo-4- (trifluoromethyl)pyrimidin-1-yl]phenoxy]phenoxy]-2-methoxy-acetate, 6-chloro-4-(2,7- dimethyl-1-naphthyl)-5-hydroxy-2-methyl-pyridazin-3-one, (2-fluorophenyl)methyl 6-amino- 5-chloro-2-(4-chloro-2-fluoro-3-methoxy-phenyl)pyrimidine-4-carboxylate, 6-amino-5- chloro-2-(4-chloro-2-fluoro-3-methoxy-phenyl)pyrimidine-4-carboxylic acid, and methyl 3- [2-chloro-5-[3,6-dihydro-3-methyl-2,6-dioxo-4-(trifluoromethyl)-1(2H)-pyrimidinyl]-4- fluorophenyl]-3a,4,5,6-tetrahydro-6-methyl-6aH-cyclopent[d]isoxazole-6a-carboxylate.

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. Thus in a further aspect there is provided a compound of Formula (I) (or a composition comprising a compound of Formula (I)) and at least one further pesticide, wherein the pesticide is selected from a herbicide, fungicide, nematicide, insecticide, and herbicide safener. Preferably the additional pesticide is a herbicide or a herbicide safener.

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.

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 present invention still further provides a method of controlling weeds at a locus said method comprising applying to the locus a weed controlling amount of a composition comprising a compound of Formula (I). Moreover, the present invention may further provide 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. Application to a locus encompasses application to the weed and/or the area surrounding said weed and/or the locus where a weed seed is located. ‘Controlling’ means killing, reducing or retarding growth or preventing or reducing germination. It is noted that the compounds of the present invention show a much-improved selectivity compared to know, structurally similar compounds. Generally the plants to be controlled are unwanted plants (weeds). ‘Locus’ means the area in which the plants are growing or will grow. The application may be applied to the locus preemergence and/or postemergence of the crop plant. Some crop plants may be inherently tolerant to herbicidal effects of compounds of Formula (I). Preferred crop plants include maize, wheat, barley soybean and rice.

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 2500 g/ha, especially from 25 to 1000 g/ha, more especially from 25 to 250 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 other herbicides or classes of herbicides (e.g. ALS-, GS-, EPSPS- , PPO-, HPPD-, -PDS , -SDPS and ACCase-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® 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.

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).

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, Brachia ria, Brom us, 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.

In a further aspect of the present invention there is provided the use of a compound of Formula (I) as defined herein as a herbicide.

Processes for preparation of compounds, e.g. a compound of Formula (I) (which optionally can be an agrochemically acceptable salt thereof), are now described, and form further aspects of the present invention. SCHEME 1

In embodiments where A¹ is -CHR¹- and X¹ is O, compounds of formula (1) may be prepared from compounds of formula (2), where LG represents a suitable leaving group (for example Br or Cl), and compounds of formula (3).

Compounds of formula (2) are treated with isoxazolidinones of formula (3), a carbonate base, for example potassium carbonate, and optionally a suitable additive, for example sodium iodide, in a suitable solvent, for example acetone.

SCHEME 2

Compounds of formula (2) may be prepared from compounds of formula (4).

For example, where LG is Cl, compounds of formula (4) are treated with a chlorinating agent, for example thionyl chloride, either neat or in a suitable solvent, for example dichloromethane.

SCHEME 3

In an alternative approach, in embodiments where A¹ is -CHR¹- and X¹ is O, compounds of formula (1) may be prepared from compounds of formula (4).

(4) (3) (1) Compounds of formula (4) are treated with isoxazolidinones of formula (3), triphenylphosphine and a suitable azodicarboxylate reagent, for example diisopropyl azodicarboxylate, in a suitable solvent, for example 2-methyltetrahydrofuran.

SCHEME 4

Compounds of formula (4) may be prepared from compounds of formula (5), where Z is H or O-alkyl.

For example, where Z is H, compounds of formula (5) are treated with a reducing agent, for example sodium borohydride, in a suitable solvent, for example a tetrahydrofuran/methanol mixture.

SCHEME 5

The synthesis routes used to access compounds of formula (5) will vary depending on the nature of Z and Q. For example, compounds of formula (6) may be prepared from compounds of formula (7).

Compounds of formula (6) are reacted under suitable formylation conditions, for example by treatment with titanium tetrachloride and dichloro(methoxy)methane in a suitable solvent, for example dichloromethane.

SCHEME 6

In an alternative approach, compounds of formula (8) may be prepared from compounds of formula (9).

Compounds of formula (9) are treated with a brominating agent, for example / - bromosuccinimide, in a suitable solvent, for example acetonitrile. SCHEME ?

Compounds of formula (9) may be prepared from compounds of formula (10), where

Z is H or O-alkyl.

For example, where Z is H, compounds of formula (10) are treated with a reducing agent, for example sodium borohydride, in a suitable solvent, for example water.

SCHEME 8

In a further alternative approach, compounds of formula (4) may be prepared from compounds of formula (11) and compounds of formula (12) where PG represents a suitable protecting group, for example -CH2CH2(Si(CH3)3), according to the following scheme.

Compounds of formula (12) are available from commercial sources. Compounds of formula (11) are reacted with compounds of formula (12) in the presence of a suitable catalyst system and a suitable base in a suitable solvent to give compounds of formula (13). For example, where PG is -CH2CH2(Si(CH3)3), compounds of formula (11) are reacted with potassium trifluoro(2-trimethylsilylethoxymethyl)boranuide in the presence of a suitable (pre-)catalyst/ligand combination, for example palladium^ I) acetate and RuPhos, and a suitable base, for example cesium carbonate, in a suitable solvent, for example a 1 ,4- dioxane/water mixture. Compounds of formula (13) are reacted under suitable deprotection conditions to give compounds of formula (4). For example, compounds of formula (13) where PG is -CH2CH2(Si(CH3)3) are treated with boron trifluoride diethyl etherate in a suitable solvent, for example dichloromethane.

SCHEME 9

Compounds of formula (11) may be prepared from compounds of formula (7).

Compounds of formula (7) are treated with a brominating agent, for example /V- bromosuccinimide, in a suitable solvent, for example acetonitrile.

SCHEME 10

Compounds of formula (5), formula (7), formula (9), formula (10) and formula (11) may be commercially available. Alternatively, they may be prepared utilising ring synthesis strategies known in the literature. The synthetic route adopted will vary depending on the nature of Z and Q. For example, where Q is Q¹, A² is O, A³ is CH2, R⁵ is H, Ci-Cealkyl, C1- Cehaloalkyl or Cs-Cecycloalkyl and R⁶ is Ci-Cealkyl, Ci-Cehaloalkyl or Cs-Cecycloalkyl, compounds of formula (14) may be prepared from compounds of formula (15) according to the following scheme. Compounds of formula (15) are available from commercial sources or may pe prepared according to strategies known in the literature.

(15) (17) (1⁴)

Compounds of formula (15) are treated with a suitable Grignard reagent (16) (where X³ is a suitable halogen), for example methylmagnesium chloride, in a suitable solvent, for example tetrahydrofuran, to give compounds of formula (17). Compounds of formula (17) are treated with a suitable base, for example potassium terf-butoxide, in a suitable solvent, for example tetrahydrofuran, to give compounds of formula (14).

SCHEME 11

Compounds of formula (18) may be prepared from compounds of formula (19).

2,2-Dimethylmalonyl chloride

For example, where R³ and R⁴ are methyl, compounds of formula (19) are treated with 2,2-dimethylmalonyl chloride and a suitable base, for example pyridine, in a suitable solvent, for example dichloromethane. SCHEME 12

Compounds of formula (19) may be prepared from compounds of formula (6) according to the following scheme.

Hydroxylamine source

Solvent Solvent

(6) (20) (19) Compounds of formula (6) are treated with a suitable source of hydroxylamine, for example hydroxylamine hydrochloride, and optionally a suitable base, for example sodium acetate, in a suitable solvent, for example ethanol, to give compounds of formula (20). Compounds of formula (20) are treated with a suitable reducing agent, for example sodium cyanoborohydride, and a suitable acid, for example 4 M hydrochloric acid in 1 ,4-dioxane, in a suitable solvent, for example methanol, to give compounds of formula (19).

SCHEME 13

Compounds of formula (3) may be commercially available. For example, the compound of formula (3) where R³ and R⁴ are methyl and R¹ is hydrogen is commercially available (CAS no 81778-07-6). Alternatively, compounds of formula (3) may be prepared synthetically. For example, where R³ and R⁴ are methyl and R¹ is Ci-Cealkoxy, Ci-Cealkoxy- Ci-Cealkoxy-, HOC(O)Ci-Cealkoxy-, Ci-C6alkoxy-C(O)-Ci-Cealkoxy- or Ci-C3alkyl-S(O)_pCi- Cealkoxy-, compounds of formula (3) may be prepared from 3,3-dichloro-2,2- dimethylpropanoic acid (21) according to the following scheme.

3,3-Dichloro-2,2-dimethylpropanoic acid (21) is treated with a suitable chlorinating agent, for example thionyl chloride, to give 3,3-dichloro-2,2-dimethylpropanoyl chloride (22). 3,3-Dichloro-2,2-dimethylpropanoyl chloride (22) is treated with a suitable source of hydroxylamine, for example hydroxylamine (50% in H2O), to give 3,3-dichloro-2,2-dimethyl- propanehydroxamic acid (23). 3,3-Dichloro-2,2-dimethyl-propanehydroxamic acid (23) is treated with an alcohol and a suitable base, for example 1 ,8-diazabicyclo(5.4.0)undec-7- ene, to give compounds of formula (3).

The following non-limiting examples provide specific synthesis methods for representative compounds of the present invention, as referred to in Table 1 below. PREPARATION EXAMPLES

Example 1 : Preparation of Compound 1.001

Step 1 : Preparation of 1-(4-bromo-2-fluoro-phenyl)-2-methyl-propan-2-ol

To a stirred solution of 1-(4-bromo-2-fluoro-phenyl)propan-2-one (5.00 g, 21.6 mmol) in dry tetrahydrofuran (140 ml), was added methylmagnesium chloride (3.00 M, 21.6 mL, 64.9 mmol) dropwise over 20 min at -78 °C. The reaction was stirred at room temperature overnight. The reaction mixture was quenched by the addition of sat. aq. ammonium chloride and the aqueous phase was extracted with ethyl acetate (x2). The combined organic portions were washed with brine, dried over Na2SC>4 and concentrated. Purification by flash column chromatography afforded 1-(4-bromo-2-fluoro-phenyl)-2- methyl-propan-2-ol (2.30 g, 9.31 mmol, 43%). ¹H NMR (400 MHz, CDCI₃) 6 ppm 7.26 - 7.20 (m, 2H), 7.16 - 7.10 (m, 1 H), 2.78 (s, 2H), 1.24 (s, 6H).

Step 2: Preparation of 6-bromo-2,2-dimethyl-3/7-benzofuran

A mixture of 1-(4-bromo-2-fluoro-phenyl)-2-methyl-propan-2-ol (2.30 g, 9.31 mmol) and potassium ferf-butoxide (1.00 M, 23.3 mL, 23.3 mmol) in tetrahydrofuran (50 mL) was stirred at 65 °C for 18 h. The reaction was quenched by addition of 1 M aq. hydrochloric acid until a pH of pH = 3 was reached. Ethyl acetate was added and the phases were separated. The organic phase was dried over Na2SC>4 and concentrated. Purification by flash column chromatography afforded 6-bromo-2,2-dimethyl-3/7-benzofuran (1.53 g, 6.73 mmol, 72%). ¹H NMR (400 MHz, CDCI₃) 5 ppm 6.98 - 6.91 (m, 2H), 6.87 - 6.84 (m, 1 H), 2.93 (s, 2H), 1.45 (s, 6H).

Step 3: Preparation of 6-bromo-2,2-dimethyl-3/7-benzofuran-5-carbaldehyde

To a solution of dichloro(methoxy)methane (1.17 mL, 12.9 mmol) and titanium tetrachloride (1.71 mL, 15.5 mmol) in dichloromethane (23 mL) was added a solution of 6- bromo-2,2-dimethyl-3/7-benzofuran (1.54 g, 6.44 mmol) in dichloromethane (7.7 mL) at 0 °C. The stirred mixture was then allowed to warm temperature. After 1 h, the mixture was cooled to 0 °C and quenched by the addition of 2 M aq. hydrochloric acid (15 mL). The mixture was allowed to warm to room temperature and was stirred for an additional 15 min. The mixture was diluted with dichloromethane and water and the phases were separated. The aqueous phase was extracted with dichloromethane and the combined organic phases were passed through a hydrophobic frit. The filtrate was adsorbed onto silica and purified by flash column chromatography (5-25% ethyl acetate in cyclohexane) to afford 6-bromo- 2,2-dimethyl-3/-/-benzofuran-5-carbaldehyde (1.31 g, 4.88 mmol, 76%). ¹H NMR (400 MHz, CDCI₃) 6 ppm 10.20 (s, 1 H), 7.75 (s, 1 H), 6.97 (s, 1 H), 3.00 (s, 2H), 1.51 (s, 6H). Step 4: Preparation of (6-bromo-2,2-dimethyl-3/7-benzofuran-5-yl)methanol

To a solution of 6-bromo-2,2-dimethyl-3/7-benzofuran-5-carbaldehyde (1.26 g, 4.69 mmol) in tetrahydrofuran (6.3 mL) and methanol (6.3 mL) was added sodium borohydride (148 mg, 3.52 mmol) at 0 °C. After 5 min, a second portion of sodium borohydride (148 mg, 3.52 mmol) was added. After a further 25 minutes, the reaction was quenched by the addition of sat. aq. ammonium chloride (10 mL). The mixture was allowed to warm to room temperature and stir for a further 15 min. The mixture was diluted with ethyl acetate and water and the phases were separated. The aqueous phase was extracted with ethyl acetate and the combined organic phases were dried over MgSCL, filtered and concentrated. Purification by flash column chromatography (5-25% ethyl acetate in cyclohexane) afforded (6-bromo-2,2-dimethyl-3/7-benzofuran-5-yl)methanol (1.15 g, 4.25 mmol, 91%). ¹H NMR (400 MHz, CDCI₃) 6 ppm 7.22 (s, 1 H), 6.93 (s, 1 H), 4.67 (s, 2H), 2.96 (s, 2H), 1.97 (br s, 1 H), 1.47 (s, 6H).

Step 5: Preparation of 2-[(6-bromo-2,2-dimethyl-3/7-benzofuran-5-yl)methyl]-4,4-dimethyl- isoxazolidin-3-one

To a solution of (6-bromo-2,2-dimethyl-3/7-benzofuran-5-yl)methanol (686 mg, 2.53 mmol), 4,4-dimethylisoxazolidin-3-one (321 mg, 2.79 mmol) and triphenylphosphine (814 mg, 3.04 mmol) in 2-methyltetrahydrofuran (10 mL) at 0 °C was added diisopropyl azodicarboxylate (0.560 mL, 2.79 mmol) dropwise. The reaction was allowed to warm to room temperature and was stirred under a nitrogen atmosphere for 1.5 h. The reaction mixture was quenched by the addition of a few drops of water and the mixture was then concentrated. Purification by reverse phase flash column chromatography (50-100% acetonitrile in water, both modified with 0.1% formic acid) afforded 2-[(6-bromo-2,2- dimethyl-3/7-benzofuran-5-yl)methyl]-4,4-dimethyl-isoxazolidin-3-one. ¹H NMR (400 MHz, CDCh) 6 ppm 7.10 (s, 1 H), 6.93 (s, 1 H), 4.75 (s, 2H), 4.01 (s, 2H), 2.95 (s, 2H), 1.47 (s, 6H), 1.26 (s, 6H).

Example 2: Preparation of Compound 1.003

Step 1 : Preparation of 5-bromo-6-fluoro-2-methyl-1 ,3-benzoxazole 2-Amino-4-bromo-5-fluoro-phenol (2.00 g, 9.71 mmol) and triethyl orthoacetate (20.0 mL) were heated at 120 °C for 6 h. The reaction mixture was concentrated onto silica gel and purified by flash column chromatography (0-10% ethyl acetate in cyclohexane) to afford 5-bromo-6-fluoro-2-methyl-1 ,3-benzoxazole (1.73 g, 7.52 mmol, 77%). ¹H NMR (400 MHz, CDCh) 6 ppm 7.81 (d, 1 H), 7.29 (d, 1 H), 2.62 (s, 3H). Step 2: Preparation of 2-[(6-fluoro-2-methyl-1 ,3-benzoxazol-5-yl)methoxy]ethyl-trimethyl- silane

5-Bromo-6-fluoro-2-methyl-1 ,3-benzoxazole (250 mg, 1.09 mmol), potassium trifluoro(2-trimethylsilylethoxymethyl)boranuide (518 mg, 2.17 mmol), palladium(ll) acetate (26.0 mg, 0.109 mmol), RuPhos (103 mg, 0.217 mmol), cesium carbonate (1.06 g, 3.26 mmol), 1 ,4-dioxane (3.0 mL) and water (0.30 mL) were heated at 150 °C for 30 min by microwave irradiation. The reaction mixture was diluted with water and extracted with ethyl acetate (x3). The organic portions were combined, washed with brine, dried over MgSC>4 and concentrated. Purification by flash column chromatography (0-20% ethyl acetate in cyclohexane) afforded 2-[(6-fluoro-2-methyl-1 ,3-benzoxazol-5-yl)methoxy]ethyl-trimethyl- silane (75% purity, 151 mg, 0.402 mmol, 37%). ¹H NMR (400 MHz, CDCI₃) 5 ppm 7.65 (d, 1 H), 7.15 (d, 1 H), 4.58 (s, 2H), 3.60 (t, 2H), 2.60 (s, 3H), 0.98 (t, 2H), 0.00 (s, 9H).

Step 3: Preparation of (6-fluoro-2-methyl-1 ,3-benzoxazol-5-yl)methanol

Boron trifluoride diethyl etherate (0.31 mL, 1.21 mmol) was added dropwise to a solution of 2-[(6-fluoro-2-methyl-1 ,3-benzoxazol-5-yl)methoxy]ethyl-trimethyl-silane (75% purity, 151 mg, 0.402 mmol) in dichloromethane (3.0 mL) under an atmosphere of nitrogen. The reaction was stirred at room temperature for 4 h then quenched with sat. aq. NaHCCh and extracted with ethyl acetate (x3). The organic portions were combined, washed with brine, dried over MgSCU and concentrated onto silica gel. Purification by flash column chromatography (0-100% ethyl acetate in cyclohexane) afforded (6-fluoro-2-methyl-1 ,3- benzoxazol-5-yl)methanol (60 mg, 0.331 mmol, 82%). ¹H NMR (400 MHz, CDCI3) 6 ppm 7.68 (d, 1 H), 7.21 (d, 1 H), 4.82 (d, 2H), 2.62 (s, 3H), 1.88 (t, 1 H).

Step 4: Preparation of 5-(chloromethyl)-6-fluoro-2-methyl-1 ,3-benzoxazole

(6-Fluoro-2-methyl-1 ,3-benzoxazol-5-yl)methanol (60 mg, 0.331 mmol) and thionyl chloride (5.0 mL) were stirred at room temperature overnight under an atmosphere of nitrogen. The reaction mixture was added dropwise to water then extracted with ethyl acetate (x3). The organic portions were combined, washed with water and brine, dried over MgSCL and concentrated to afford crude 5-(chloromethyl)-6-fluoro-2-methyl-1 ,3- benzoxazole (83 mg). ¹H NMR (400 MHz, CDCh) 6 ppm 7.65 (d, 1 H), 7.21 (d, 1 H), 4.72 (s, 2H), 2.62 (s, 3H).

Step 5: Preparation of 2-[(6-fluoro-2-methyl-1 ,3-benzoxazol-5-yl)methyl]-4,4-dimethyl- isoxazolidin-3-one 5-(Chloromethyl)-6-fluoro-2-methyl-1 ,3-benzoxazole (crude from Step 4; 83 mg),

4.4-dimethylisoxazolidin-3-one (46 mg, 0.40 mmol), sodium iodide (5.0 mg, 0.033 mmol), potassium carbonate (169 mg, 1.16 mmol) and acetone (2.0 mL) were combined and stirred at room temperature overnight. The reaction mixture was diluted with water and extracted with ethyl acetate (x3). The organic portions were combined, washed with brine, dried over MgSC>4 and concentrated onto silica gel. Purification by flash chromatography (0-100% ethyl acetate in cyclohexane) afforded 2-[(6-fluoro-2-methyl-1,3-benzoxazol-5-yl)methyl]-

4.4-dimethyl-isoxazolidin-3-one. ¹H NMR (400 MHz, CDCI₃) 5 ppm 7.59 (d, 1 H), 7.20 (d, 1 H), 4.83 (s, 2H), 3.99 (s, 2H), 2.61 (s, 3H), 1.23 (s, 6H).

Example 3: Preparation of Compound 1.004

Step 1 : Preparation of (6-bromo-2-methyl-1 ,3-benzoxazol-5-yl)methanol

To a stirred solution of (2-methyl-1 ,3-benzoxazol-5-yl)methanol (0.619 g, 3.79 mmol) in acetonitrile (9.3 mL) was added /V-bromosuccinimide (0.689 g, 3.79 mmol). The reaction mixture was heated at 65 °C for 3 h then diluted with water and extracted with ethyl acetate (x3). The combined organic layers were washed with brine, dried over Mg2SC>4 and concentrated. Purification by flash column chromatography (0-100% ethyl acetate in cyclohexane) afforded (6-bromo-2-methyl-1 ,3-benzoxazol-5-yl)methanol (0.280 g, 1.16 mmol, 30%). ¹H NMR (400 MHz, CDCI₃) 6 ppm 7.80 (s, 1 H), 7.70 (s, 1 H), 4.84 (d, 2H), 2.65 (s, 3H), 2.15 (br t, 1 H).

Step 2: Preparation of 6-bromo-5-(chloromethyl)-2-methyl-1 ,3-benzoxazole

Thionyl chloride (3.26 g, 2.00 mL, 27.3 mmol) and (6-bromo-2-methyl-1 ,3- benzoxazol-5-yl)methanol (134 mg, 0.55 mmol) were combined and stirred at room temperature overnight. The reaction mixture was cooled to 0 °C then quenched by the addition of water and extracted with ethyl acetate (x3). The combined organic layers were washed with brine, dried over Mg2SC>4 and concentrated to afford 6-bromo-5- (chloromethyl)-2-methyl-1 ,3-benzoxazole (0.131 g, 0.50 mmol, 90%). ¹H NMR (400 MHz, CDCI₃) 6 ppm 7.78 (s, 1H), 7.75 (s, 1 H), 4.80 (s, 2H), 2.64 (s, 3H).

Step 3: Preparation of 2-[(6-bromo-2-methyl-1 ,3-benzoxazol-5-yl)methyl]-4,4-dimethyl- isoxazolidin-3-one

Potassium carbonate (106 mg, 0.75 mmol) and 4,4-dimethylisoxazolidin-3-one (70 mg, 0.60 mmol) were added to a solution of 6-bromo-5-(chloromethyl)-2-methyl-1 ,3- benzoxazole (131 mg, 0.50 mmol) in acetone (3.9 mL). The reaction was stirred over a weekend at room temperature then sodium iodide (7 mg, 0.05 mmol) was added and the reaction mixture was stirred at room temperature overnight. The reaction mixture was diluted with water and extracted with ethyl acetate (x3). The combined organic layers were washed with brine, dried over MgSC>4 and concentrated. Purification by flash column chromatography (0-50% ethyl acetate in cyclohexane) afforded 2-[(6-bromo-2-methyl-1,3- benzoxazol-5-yl)methyl]-4,4-dimethyl-isoxazolidin-3-one. ¹H NMR (400 MHz, CDCh) 5 ppm 7.70 (s, 1 H), 7.61 (s, 1 H), 4.90 (s, 2H), 4.06 (s, 2H), 2.65 (s, 3H), 1.30 (s, 6H).

Additional compounds of the invention, made in an analogous manner to those described above in Examples 1 to 3 are shown in Table 1 below.

Table 1. Compounds of the present invention

BIOLOGICAL EXAMPLES

Seeds of a variety of test species are sown in standard soil in pots Leptochloa chinesis (LEFCH), Echinochloa crus-galli (ECHCG) and Cyperus esculentus (CYPES). After cultivation for one day (pre-emergence) or after 13 days cultivation (post-emergence) under controlled conditions in a glasshouse (at 30/20°C, day/night; 18 hours light; 75% humidity), the plants are sprayed with an aqueous spray solution derived from the dissolution 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, which was then diluted to required concentration using 0.2% Genapol XO80 (CAS No.9043-30-5) in water as the diluent. Compounds are applied at 500 g/ha. The test plants are then grown in a glasshouse under controlled conditions in a glasshouse (at 30/20°C, day/night; 18 hours light; 75% 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 = 81-100%; 4 = 61-80%; 3=41-60%; 2=21-40%; 1=0-20%).

Claims

1. A compound of Formula (I),

or a salt thereof, wherein:

A¹ is CHR¹or C(O);

R¹ is selected from the group consisting of hydrogen, halogen, hydroxy, Ci- Cealkoxy, Ci-Cealkoxy-Ci-Cealkoxy-, Ci-C3alkyl-C(O)O-, HOC(O)Ci-Cealkoxy-, Ci- C6alkoxy-C(O)-Ci-Cealkoxy-, Ci-C3alkyl-S(O)_p- and Ci-C3alkyl-S(O)_pCi-C6alkoxy-;

R³ and R⁴ are each independently Ci-Csalkyl;

X¹ is O or S; and

Q is Q¹ or Q²

wherein the jagged line denotes the point of attachment to the rest of the molecule; X² is bromo or fluoro;

R⁵ and R⁶ are each independently selected from the group consisting of hydrogen, halogen, Ci-Cealkyl, Ci-Cehaloalkyl, Cs-Cecycloalkyl and Ci-Cealkoxy-; or

R⁵ and R⁶ together are =0 or -(CH2)n-; n is independently an integer of 2, 3, 4 ,5 or 6;

A² and A³ are each independently selected from the group consisting of CR⁷R⁸, C(O), O, S(O)_p and N(R⁹); each R⁷ is independently selected from the group consisting of hydrogen, halogen, Ci-Cealkyl, Ci-Cehaloalkyl, Cs-Cecycloalkyl and Ci-Cealkoxy-; and each R⁸ is independently selected from the group consisting of hydrogen, halogen, Ci-Cealkyl, Ci-Cehaloalkyl, Cs-Cecycloalkyl and Ci-Cealkoxy-; or R⁷ and R⁸ together with the carbon atom to which they are bonded form a 3- to 7-membered carbocyclic ring; each R⁹ is hydrogen or Ci-Csalkyl;

A⁵, A⁶ and A⁷ are each independently selected from the group consisting of C(R¹⁰), N(R¹¹)q, S and O, each q is an integer or 0 or 1 ; each R¹⁰ is independently selected from the group consisting of hydrogen, halogen, Ci-Csalkyl, aryl, Ci-Cshaloalkyl, Ci-Cshaloalkoxy-, Ci-Csalkoxy-, and C3- Cecycloalkyl; each R¹¹ is independently selected from the group consisting of hydrogen, C1- Csalkyl- and Ci-Cshaloalkyl; and, each p is independently an integer of 0, 1 or 2;

2. The compound of Formula (I) according to claim 1 , wherein X¹ is O.

3. The compound of Formula (I) according to claim 1 or claim 2, wherein R³ and R⁴ are methyl.

4. The compound of Formula (I) according to any one of the previous claims, wherein A¹ is CHR¹.

5. The compound of Formula (I) according to claim 4, wherein R¹ is hydrogen, hydroxy, or Ci-Cealkoxy.

6. The compound of Formula (I) according to any one of claims 1 to 3, wherein A¹ is C(O).

7. The compound according to any one of the previous claims, wherein Q is Q¹.

8. The compound according to claim 7, wherein A² is O.

9. The compound according to claim 7 or claim 8, wherein A² and A³ are both O.

10. The compound according to any one of claims 7 to 9, wherein R⁵ and R⁶ are independently selected from the group consisting of hydrogen, methyl and fluoro.

11. The compound according to any one of claims 1 to 6, wherein Q is Q².

12. The compound according to claim 11 , wherein each R¹⁰ is independently selected from the group consisting of hydrogen, Ci-Csalkyl, Cs-Cecyloalkyl, phenyl, benzyl, Ci-Cshaloalkyl, Ci-Cshaloalkoxy-, and Ci-Csalkoxy-.

13. The compound according to claim 11 or 12, wherein each R¹¹ is independently selected from the group consisting of hydrogen, methyl, ethyl and cyclopropyl.

14. A herbicidal composition comprising a compound of Formula (I) according to any one of the previous claims and an agriculturally acceptable formulation adjuvant.

15. A method of controlling weeds at a locus comprising applying to the locus a weed controlling amount of a compound as defined in any one of claims 1 to 13 or a weed controlling amount of a composition as defined in claim 14.

16. Use of a compound of Formula (I) as defined in any one of claims 1 to 13 as a herbicide.