The present invention relates to herbicidally active pyridazine derivatives, as well as to processes and intermediates used for the preparation of such derivatives. The invention further extends to herbicidal compositions comprising such derivatives, as well as to the use of such compounds and compositions for controlling undesirable plant growth: in particular the use for controlling weeds, in crops of useful plants.

The present invention is based on the finding that pyridazine derivatives of formula (I) as defined herein, exhibit surprisingly good herbicidal activity. Thus, according to the present invention there is provided a compound of formula (I) or an agronomically acceptable salt or zwitterionic species thereof:

wherein

R ¹ is selected from the group consisting of hydrogen, halogen, Ci-C6alkyl, C2-C6alkenyl, C2- Cealkynyl, Cs-Cecycloalkyl, Ci-C ₆ haloalkyl, -OR ⁷ , -OR ^15a , -N(R ⁶ )S(0) ₂ R ¹⁵ , -N(R ⁶ )C(0)R ¹⁵ , - N(R ⁶ )C(0)0R ¹⁵ , -N(R ⁶ )C(0)NR ¹⁶ R ¹⁷ , -N(R ⁶ )CHO, -N(R ^7a ) ₂ and -S(0) _r R ¹⁵ ;

R ² is selected from the group consisting of hydrogen, halogen, Ci-C6alkyl and Ci-C6haloalkyl;

and wherein when R ¹ is selected from the group consisting of -OR ⁷ , -OR ^15a , -N(R ⁶ )S(0) ₂ R ¹⁵ , - N(R ⁶ )C(0)R ¹⁵ , -N(R ⁶ )C(0)0R ¹⁵ , -N(R ⁶ )C(0)NR ¹⁶ R ¹⁷ , -N(R ⁶ )CHO, -N(R ^7a ) ₂ and -S(0) _r R ¹⁵ , then R ² is selected from the group consisting of hydrogen and Ci-C6alkyl; or

R ¹ and R ² together with the carbon atom to which they are attached form a C3-C6cycloalkyl ring or a 3- to 6- membered heterocyclyl, which comprises 1 or 2 heteroatoms individually selected from N and O;

Q is (CR ^1a R ^2b ) _m ;

m is 0, 1 , 2 or 3;

each R ^1a and R ^2b are independently selected from the group consisting of hydrogen, halogen, Ci-Cealkyl, Ci-C ₆ haloalkyl, -OH, -OR ⁷ , -OR ^15a , -NH ₂ , -NHR ⁷ , -NHR ^15a , -N(R ⁶ )CHO, -NR ^7b R ^7c and - S(0) _r R ¹⁵ ; or

each R ^1a and R ^2b together with the carbon atom to which they are attached form a C3- C6cycloalkyl ring or a 3- to 6- membered heterocyclyl, which comprises 1 or 2 heteroatoms individually selected from N and O;

R ³ , R ⁴ and R ⁵ are independently selected from the group consisting of hydrogen, halogen, cyano, nitro, -S(0) _r R ¹⁵ , Ci-C6alkyl, Ci-C6fluoroalkyl, Ci-C6fluoroalkoxy, Ci-C6alkoxy, C3-C6cycloalkyl and -N(R ⁶ ) ₂ ;

each R ⁶ is independently selected from hydrogen and Ci-C6alkyl;

each R ⁷ is independently selected from the group consisting of Ci-C6alkyl, -S(0) ₂ R ¹⁵ , -C(0)R ¹⁵ , -C(0)0R ¹⁵ and -C(0)NR ¹⁶ R ¹⁷ ; each R ^7a is independently selected from the group consisting of -S(0) ₂ R ¹⁵ , -C(0)R ¹⁵ , -C(0)0R ¹⁵ -C(0)NR ¹⁶ R ¹⁷ and -C(0)NR ⁶ R ^15a ;

R ^7b and R ^7c are independently selected from the group consisting of Ci-C6alkyl, -S(0) ₂ R ¹⁵ , - C(0)R ¹⁵ , -C(0)0R ¹⁵ , -C(0)NR ¹⁶ R ¹⁷ and phenyl, and wherein said phenyl is optionally substituted by 1 , 2 or 3 R ⁹ substituents, which may be the same or different; or

R ^7b and R ^7c together with the nitrogen atom to which they are attached form a 4- to 6-membered heterocyclyl ring which optionally comprises one additional heteroatom individually selected from N, O and S; and

A is a six-membered heterocyclic aromatic ring containing 1 , 2 or 3 nitrogen atoms in the ring and having one keto group on a ring carbon atom, wherein one nitrogen atom is substituted with the group R ³⁰ and optionally substituted with p R ⁸ substituents on ring carbon atoms, which may be the same or different,

p is 0, 1 , 2 or 3;

and wherein when p is 1 or 2, then each R ⁸ is independently selected from the group consisting of halogen, nitro, cyano, -NH ₂ , -NHR ⁷ , -N(R ⁷ ) ₂ , -OH, -OR ⁷ , -S(0) _r R ¹⁵ , -NR ⁶ S(0) ₂ R ¹⁵ , - C(0)OR ¹⁰ , -C(0)R ¹⁵ , -C(0)NR ¹⁶ R ¹⁷ , -S(0) ₂ NR ¹⁶ R ¹⁷ , Ci-C ₆ alkyl, Ci-C ₆ haloalkyl, Cs-Cecycloalkyl, C ₃ - Cehalocycloalkyl, C3-C6cycloalkoxy, C2-C6alkenyl, C2-C6haloalkenyl, C2-C6alkynyl, Ci-C3alkoxyCi- C3alkyl-, Ci-C6alkoxy, hydroxyCi-Cealkyl-, Ci-C3alkoxyCi-C3alkoxy-, Ci-C6haloalkoxy, Ci- C3haloalkoxyCi-C3alkyl-, C3-C6alkenyloxy, C3-C6alkynyloxy, N-C3-C6cycloalkylamino, -C(R ⁶ )=NOR ⁶ , Ci-C ₄ haloalkylthio, Ci-C ₄ haloalkylsulfinyl, Ci-C ₄ haloalkylsulfonyl, Ci-C ₄ Sulfonyloxy, C1-C4- halosulfonyloxy, Ci-C ₄ alkylthioCi-C ₄ alkyl, Ci-C ₄ alkylsulfinylCi-C ₄ alkyl, Ci-C ₄ alkylsulfonylCi-C ₄ alkyl, phenyl, a 3- to 6- membered heterocyclyl, which comprises 1 or 2 heteroatoms individually selected from N and O, and a 5- or 6- membered heteroaryl, which comprises 1 , 2, 3 or 4 heteroatoms individually selected from N, O and S, and wherein said phenyl, heterocyclyl or heteroaryl are optionally substituted by 1 , 2 or 3 R ⁹ substituents, which may be the same or different;

and when p is 3, then each R ⁸ is independently selected from the group consisting of halogen, nitro, cyano, -NH ₂ , -NHR ⁷ , -N(R ⁷ ) ₂ , -OR ⁷ , S(0) _r R ¹⁵ , -NR ⁶ S(0) ₂ R ¹⁵ , -C(0)OR ¹⁰ , -C(0)R ¹⁵ , -C(0)NR ¹⁶ R ¹⁷ , -S(0) ₂ NR ¹⁶ R ¹⁷ , Ci-C6alkyl, Ci-C6haloalkyl, C3-C6cycloalkyl, Ci-C3alkoxyCi-C3alkyl-, Ci-C6alkoxy, hydroxyCi-Cealkyl-, Ci-C ₄ alkylthioCi-C ₄ alkyl, Ci-C ₄ alkylsulfinylCi-C ₄ alkyl, Ci-C ₄ alkylsulfonylCi-C ₄ alkyl; and each R ⁹ is independently selected from the group consisting of halogen, cyano, -OH, -N(R ⁶ )2, Ci- C ₄ alkyl, Ci-C ₄ alkoxy, Ci-C ₄ haloalkyl and Ci-C ₄ haloalkoxy;

X is selected from the group consisting of C3-C6cycloalkyl, phenyl, a 5- or 6- membered heteroaryl, which comprises 1 , 2, 3 or 4 heteroatoms individually selected from N, O and S, and a 4- to 6- membered heterocyclyl, which comprises 1 , 2 or 3 heteroatoms individually selected from N, O and S, and wherein said cycloalkyl, phenyl, heteroaryl or heterocyclyl moieties are optionally independently substituted by 1 or 2 substituents R ⁹ , and wherein the aforementioned CR ¹ R ² , Q and Z moieties may be attached at any position of said cycloalkyl, phenyl, heteroaryl or heterocyclyl moieties;

n is 0 or 1 ;

Z is selected from the group consisting of -C(0)OR ¹⁰ , -CH2OH, -CHO, -C(0)NH0R ¹¹ , - C(0)NHCN, -0C(0)NH0R ¹¹ , -0C(0)NHCN, -NR ⁶ C(0)NH0R ¹¹ , -NR ⁶ C(0)NHCN, -C(0)NHS(0) ₂ R ¹² , - 0C(0)NHS(0) ₂ R ¹² , -NR ⁶ C(0)NHS(0) ₂ R ¹² , -S(0) ₂ 0R ¹⁰ , -0S(0) ₂ 0R ¹⁰ , -NR ⁶ S(0) ₂ 0R ¹⁰ , -NR ⁶ S(0)OR ¹⁰ , -NHS(0) ₂ R ¹⁴ , -S(0)OR ¹⁰ , -OS(0)OR ¹⁰ , -S(0) ₂ NHCN, -S(0) ₂ NHC(0)R ¹⁸ , -S(0) ₂ NHS(0) ₂ R ¹² , - 0S(0) ₂ NHCN, -0S(0) ₂ NHS(0) ₂ R ¹² , -0S(0) ₂ NHC(0)R ¹⁸ , -NR ⁶ S(0) ₂ NHCN, -NR ⁶ S(0) ₂ NHC(0)R ¹⁸ , - N(0H)C(0)R ¹⁵ , -0NHC(0)R ¹⁵ , -NR ⁶ S(0) ₂ NHS(0) ₂ R ¹² , -P(0)(R ¹³ )(OR ¹⁰ ), -P(0)H(OR ¹⁰ ), -

0P(0)(R ¹³ )(0R ¹ °), -NR ⁶ P(0)(R ¹³ )(OR ¹⁰ ) and tetrazole;

R ¹⁰ is selected from the group consisting of hydrogen, Ci-C6alkyl, phenyl and benzyl, and wherein said phenyl or benzyl are optionally substituted by 1 , 2 or 3 R ⁹ substituents, which may be the same or different;

R ¹¹ is selected from the group consisting of hydrogen, Ci-C6alkyl and phenyl, and wherein said phenyl is optionally substituted by 1 , 2 or 3 R ⁹ substituents, which may be the same or different;

R ¹² is selected from the group consisting of Ci-C6alkyl, Ci-C6haloalkyl, Ci-C6alkoxy, -OH, - N(R ⁶ ) ₂ and phenyl, and wherein said phenyl is optionally substituted by 1 , 2 or 3 R ⁹ substituents, which may be the same or different;

R ¹³ is selected from the group consisting of -OH, Ci-C6alkyl, Ci-C6alkoxy and phenyl;

R ¹⁴ is Ci-Cehaloalkyl;

R ¹⁵ is selected from the group consisting of Ci-C6alkyl and phenyl, and wherein said phenyl is optionally substituted by 1 , 2 or 3 R ⁹ substituents, which may be the same or different;

R ^15a is phenyl, wherein said phenyl is optionally substituted by 1 , 2 or 3 R ⁹ substituents, which may be the same or different;

R ¹⁶ and R ¹⁷ are independently selected from the group consisting of hydrogen and Ci-C6alkyl; or R ¹⁶ and R ¹⁷ together with the nitrogen atom to which they are attached form a 4- to 6-membered heterocyclyl ring which optionally comprises one additional heteroatom individually selected from N, O and S;

R ¹⁸ is selected from the group consisting of hydrogen, Ci-C6alkyl, Ci-C6haloalkyl, Ci-C6alkoxy, -N(R ⁶ ) ₂ and phenyl, and wherein said phenyl is optionally substituted by 1 , 2 or 3 R ⁹ substituents, which may be the same or different;

R ³⁰ is selected from the group consisting of -OH, -OR ⁷ , -S(0) _r R ¹⁵ , -C(0)OR ¹⁰ , -C(0)R ¹⁵ , - C(0)NR ¹⁶ R ¹⁷ , -S(0) ₂ NR ¹⁶ R ¹⁷ , -NH ₂ , -NHR ⁷ , N(R ⁷ ) ₂ , R ¹⁵ S(0) _r Ci-C ₃ alkyl-, R ¹⁶ R ¹⁷ NS(0) ₂ Ci-C ₃ alkyl-, R ¹⁵ C(0)Ci-C ₃ alkyl-, R ¹⁰ OC(O)Ci-C ₃ alkyl-, R ¹⁶ R ¹⁷ NC(0)Ci-C ₃ alkyi-, H ₂ NCi-C ₃ alkyl-, R ⁷ HNCi-C ₃ alkyl-, (R ⁷ ) ₂ NCi-C ₃ alkyl-, Ci-C6alkyl, Ci-C6haloalkyl, C ₃ -C6cycloalkyl, C ₃ -C6cycloalkoxy, C ₃ -C6cycloalkylCi- C ₃ alkyl-, C ₃ -C6cycloalkylCi-C ₃ alkoxy-, C ₂ -C6alkenyl, C ₂ -C6haloalkenyl, C ₂ -C6alkynyl, Ci-C ₃ alkoxyCi- C ₃ alkyl-, Ci-C6alkoxy, hydroxyCi-Cealkyl-, cyanoCi-Cealkyl-, Ci-C ₃ alkoxyCi-C ₃ alkoxy-, Ci-C6haloalkoxy, Ci-C ₃ haloalkoxyCi-C ₃ alkyl-, C ₃ -C6alkenyloxy, C ₃ -C6alkynyloxy, -C(R ⁶ )=NOR ⁶ , phenyl, phenylCi- C ₂ alkyl-, heterocyclyl, heterocyclylCi-C ₂ alkyl-, wherein the heterocyclyl moiety is a 4- to 6-membered saturated or partially saturated ring which comprises 1 , 2 or 3 heteroatoms individually selected from N, O and S(0)r, heteroaryl and heteroarylCi-C ₂ alkyl-, wherein the heteroaryl is a 5- or 6- membered aromatic ring, which comprises 1 , 2, 3 or 4 heteroatoms independently selected from N, O and S, and wherein said C ₃ -C6cycloalkyl, C ₃ -C6cycloalkylCi-C ₃ alkyl-, phenyl, phenylCi-C ₂ alkyl-, heterocyclyl, heterocyclylCi-C ₂ alkyl-, heteroaryl or heteroarylCi-C ₂ alkyl-, are optionally substituted by 1 , 2 or 3 R ⁹ substituents, which may be the same or different; and

r is 0, 1 or 2. According to a second aspect of the invention, there is provided an agrochemical composition comprising a herbicidally effective amount of a compound of formula (I) and an agrochemically- acceptable diluent or carrier. Such an agricultural composition may further comprise at least one additional active ingredient.

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

According to a fourth aspect of the invention, there is provided the use of a compound of formula (I) as a herbicide.

According to a fifth aspect of the invention, there is provided a process for the preparation of compounds of formula (I).

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

As used herein, cyano means a -CN group.

As used herein, hydroxy means an -OH group.

As used herein, nitro means an -NO ₂ group.

As used herein, the term "Ci-C6alkyl" refers to a straight or branched hydrocarbon chain radical consisting solely of carbon and hydrogen atoms, containing no unsaturation, having from one to six carbon atoms, and which is attached to the rest of the molecule by a single bond. Ci-C4alkyl and Ci- C ₂ alkyl are to be construed accordingly. Examples of Ci-C6alkyl include, but are not limited to, methyl (Me), ethyl (Et), n-propyl, 1 -methylethyl (iso-propyl), n-butyl, and 1 -dimethylethyl (f-butyl).

As used herein, the term "Ci-C6alkoxy" refers to a radical of the formula -OR _a where R _a is a Ci- C6alkyl radical as generally defined above. Ci-C4alkoxy is to be construed accordingly. Examples of Ci- 4alkoxy include, but are not limited to, methoxy, ethoxy, propoxy, iso-propoxy and f-butoxy.

As used herein, the term "Ci-C6haloalkyl" refers to a Ci-C6alkyl radical as generally defined above substituted by one or more of the same or different halogen atoms. Ci-C4haloalkyl is to be construed accordingly. Examples of Ci-C6haloalkyl include, but are not limited to chloromethyl, fluoromethyl, fluoroethyl, difluoromethyl, trifluoromethyl and 2,2,2-trifluoroethyl.

As used herein, the term "C ₂ -C6alkenyl" refers to a straight or branched hydrocarbon chain radical group consisting solely of carbon and hydrogen atoms, containing at least one double bond that can be of either the (E)- or (^-configuration, having from two to six carbon atoms, which is attached to the rest of the molecule by a single bond. C2-C4alkenyl is to be construed accordingly. Examples of C ₂ -C6alkenyl include, but are not limited to, prop-1 -enyl, allyl (prop-2-enyl) and but-1 -enyl.

As used herein, the term“C ₂ -C6haloalkenyl” refers to a C ₂ -C6alkenyl radical as generally defined above substituted by one or more of the same or different halogen atoms. Examples of C ₂ -C6haloalkenyl include, but are not limited to chloroethylene, fluoroethylene, 1 ,1 -difluoroethylene, 1 ,1 -dichloroethylene and 1 ,1 ,2-trichloroethylene.

As used herein, the term "C ₂ -C6alkynyl" refers to a straight or branched hydrocarbon chain radical group consisting solely of carbon and hydrogen atoms, containing at least one triple bond, having from two to six carbon atoms, and which is attached to the rest of the molecule by a single bond. C2-C4alkynyl is to be construed accordingly. Examples of C2-C6alkynyl include, but are not limited to, prop-1 -ynyl, propargyl (prop-2-ynyl) and but-1 -ynyl.

As used herein, the term "Ci-C6haloalkoxy" refers to a Ci-C6alkoxy group as defined above substituted by one or more of the same or different halogen atoms. Ci-C ₄ haloalkoxy is to be construed accordingly. Examples of Ci-C6haloalkoxy include, but are not limited to, fluoromethoxy, difluoromethoxy, fluoroethoxy, trifluoromethoxy and trifluoroethoxy.

As used herein, the term "Ci-C3haloalkoxyCi-C3alkyl" refers to a radical of the formula Rb-0-R _a - where Rb is a Ci-C3haloalkyl radical as generally defined above, and R _a is a Ci-C3alkylene radical as generally defined above.

As used herein, the term "Ci-C3alkoxyCi-C3alkyl" refers to a radical of the formula Rb-0-R _a - where Rb is a Ci-C3alkyl radical as generally defined above, and R _a is a Ci-C3alkylene radical as generally defined above.

As used herein, the term " Ci-C3alkoxyCi-C3alkoxy-" refers to a radical of the formula Rb-0-R _a - O- where Rb is a Ci-C3alkyl radical as generally defined above, and R _a is a Ci-C3alkylene radical as generally defined above.

As used herein, the term "C3-C6alkenyloxy" refers to a radical of the formula -OR _a where R _a is a C3-C6alkenyl radical as generally defined above.

As used herein, the term "C3-C6alkynyloxy" refers to a radical of the formula -OR _a where R _a is a C3-C6alkynyl radical as generally defined above.

As used herein, the term“hydroxyCi-Cealkyl” refers to a Ci-C6alkyl radical as generally defined above substituted by one or more hydroxy groups.

As used herein, the term "Ci-C6alkylcarbonyl" refers to a radical of the formula -C(0)R _a where R _a is a Ci-C6alkyl radical as generally defined above.

As used herein, the term "Ci-C6alkoxycarbonyl" refers to a radical of the formula -C(0)0R _a where R _a is a Ci-C6alkyl radical as generally defined above.

As used herein, the term“aminocarbonyl” refers to a radical of the formula -C(0)NH ₂ .

As used herein, the term "C3-C6cycloalkyl" refers to a stable, monocyclic ring radical which is saturated or partially unsaturated and contains 3 to 6 carbon atoms. C3-C ₄ cycloalkyl is to be construed accordingly. Examples of C3-C6cycloalkyl include, but are not limited to, cyclopropyl, cyclobutyl, cyclopentyl and cyclohexyl.

As used herein, the term "C3-C6halocycloalkyl" refers to a C3-C6cycloalkyl radical as generally defined above substituted by one or more of the same or different halogen atoms. C3-C ₄ halocycloalkyl is to be construed accordingly.

As used herein, the term "C3-C6cycloalkoxy" refers to a radical of the formula -OR _a where R _a is a C3-C6cycloalkyl radical as generally defined above.

As used herein, the term“N-C3-C6cycloalkylamino” refers to a radical of the formula -NHR _a where R _a is a C3-C6cycloalkyl radical as generally defined above.

As used herein, except where explicitly stated otherwise, the term "heteroaryl" refers to a 5- or 6- membered monocyclic aromatic ring which comprises 1 , 2, 3 or 4 heteroatoms individually selected from nitrogen, oxygen and sulfur. The heteroaryl radical may be bonded to the rest of the molecule via a carbon atom or heteroatom. Examples of heteroaryl include, furyl, pyrrolyl, imidazolyl, thienyl, pyrazolyl, thiazolyl, isothiazolyl, oxazolyl, isoxazolyl, triazolyl, tetrazolyl, pyrazinyl, pyridazinyl, pyrimidyl or pyridyl.

As used herein, except where explicitly stated otherwise, the term "heterocyclyl" or "heterocyclic" refers to a stable 4- to 6-membered non-aromatic monocyclic ring radical which comprises 1 , 2, or 3 heteroatoms individually selected from nitrogen, oxygen and sulfur. The heterocyclyl radical may be bonded to the rest of the molecule via a carbon atom or heteroatom. Examples of heterocyclyl include, but are not limited to, pyrrolinyl, pyrrolidyl, tetrahydrofuryl, tetrahydrothienyl, tetrahydrothiopyranyl, piperidyl, piperazinyl, tetrahydropyranyl, dihydroisoxazolyl, dioxolanyl, morpholinyl or d-lactamyl.

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

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

For example a compound of formula (I) wherein Z comprises an acidic proton, may exist as a zwitterion, a compound of formula (l-l), or as an agronomically acceptable salt, a compound of formula (l-ll) as shown below:

wherein, Y represents an agronomically acceptable anion and j and k represent integers that may be selected from 1 , 2 or 3, dependent upon the charge of the respective anion Y.

A compound of formula (I) may also exist as an agronomically acceptable salt of a zwitterion, a compound of formula (l-lll) as shown below: (l-lll)

wherein, Y represents an agronomically acceptable anion, M represents an agronomically acceptable cation (in addition to the pyridazinium cation) and the integers j, k and q may be selected from 1 , 2 or 3, dependent upon the charge of the respective anion Y and respective cation M.

Thus where a compound of formula (I) is drawn in protonated form herein, the skilled person would appreciate that it could equally be represented in unprotonated or salt form with one or more relevant counter ions.

In one embodiment of the invention there is provided a compound of formula (l-ll) wherein k is 2, j is 1 and Y is selected from the group consisting of halogen, trifluoroacetate and pentafluoropropionate. In this embodiment a nitrogen atom comprised in R ¹ , R ² , R ³ , R ⁴ , R ⁵ , A, Q or X may be protonated.

Suitable agronomically acceptable salts of the present invention, represented by an anion Y, include but are not limited chloride, bromide, iodide, fluoride, 2-naphthalenesulfonate, acetate, adipate, methoxide, ethoxide, propoxide, butoxide, aspartate, benzenesulfonate, benzoate, bicarbonate, bisulfate, bitartrate, butylsulfate, butylsulfonate, butyrate, camphorate, camsylate, caprate, caproate, caprylate, carbonate, citrate, diphosphate, edetate, edisylate, enanthate, ethanedisulfonate, ethanesulfonate, ethylsulfate, formate, fumarate, gluceptate, gluconate, glucoronate, glutamate, glycerophosphate, heptadecanoate, hexadecanoate, hydrogen sulfate, hydroxide, hydroxynaphthoate, isethionate, lactate, lactobionate, laurate, malate, maleate, mandelate, mesylate, methanedisulfonate, methylsulfate, mucate, myristate, napsylate, nitrate, nonadecanoate, octadecanoate, oxalate, pelargonate, pentadecanoate, pentafluoropropionate, perchlorate, phosphate, propionate, propylsulfate, propylsulfonate, succinate, sulfate, tartrate, tosylate, tridecylate, triflate, trifluoroacetate, undecylinate and valerate.

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

Preferred compounds of formula (I), wherein Z comprises an acidic proton, can be represented as either (l-l) or (l-ll). For compounds of formula (l-ll) emphasis is given to salts when Y is chloride, bromide, iodide, hydroxide, bicarbonate, acetate, pentafluoropropionate, triflate, trifluoroacetate, methylsulfate, tosylate and nitrate, wherein j and k are 1 . Preferably, Y is chloride, bromide, iodide, hydroxide, bicarbonate, acetate, trifluoroacetate, methylsulfate, tosylate and nitrate, wherein j and k are 1 . For compounds of formula (l-ll) emphasis is also given to salts when Y is carbonate and sulfate, wherein j is 2 and k is 1 , and when Y is phosphate, wherein j is 3 and k is 1 .

Where appropriate compounds of formula (I) may also be in the form of (and/or be used as) an N-oxide.

Compounds of formula (I) wherein m is 0 and n is 0 may be represented by a compound of formula (l-la) as shown below:

(l-la)

wherein R ¹ , R ² , R ³ , R ⁴ , R ⁵ , A and Z are as defined for compounds of formula (I).

Compounds of formula (I) wherein m is 1 and n is 0 may be represented by a compound of formula (l-lb) as shown below:

(l-lb)

wherein R ¹ , R ² , R ^1a , R ^2b , R ³ , R ⁴ , R ⁵ , A and Z are as defined for compounds of formula (I). Compounds of formula (I) wherein m is 2 and n is 0 may be represented by a compound of formula (l-lc) as shown below:

(l-lc)

wherein R ¹ , R ² , R ^1a , R ^2b , R ³ , R ⁴ , R ⁵ , A and Z are as defined for compounds of formula (I).

Compounds of formula (I) wherein m is 3 and n is 0 may be represented by a compound of formula (l-ld) as shown below:

(l-ld)

wherein R ¹ , R ² , R ^1a , R ^2b , R ³ , R ⁴ , R ⁵ , A and Z are as defined for compounds of formula (I).

The following list provides definitions, including preferred definitions, for substituents n, m, p, r, A, Q, X, Z, R ¹ , R ² , R ^1a , R ^2b , R ³ , R ⁴ , R ⁵ , R ⁶ , R ⁷ , R ^7a , R ^7b , R ^7c , R ⁸ , R ⁹ , R ¹⁰ , R ¹¹ , R ¹² , R ¹³ , R ¹⁴ , R ¹⁵ , R ^15a , R ¹⁶ , R ¹⁷ , R ¹⁸ and R ³⁰ with reference to the compounds of formula (I) according to the invention. For any one of these substituents, any of the definitions given below may be combined with any definition of any other substituent given below or elsewhere in this document.

Preferably, R ¹ is selected from the group consisting of hydrogen, halogen, Ci-C6alkyl, Ci- Cefluoroalkyl, -OR ⁷ , -NHS(0) ₂ R ¹⁵ , -NHC(0)R ¹⁵ , -NHC(0)0R ¹⁵ , -NHC(0)NR ¹⁶ R ¹⁷ , -N(R ^7a ) ₂ and - S(0)rR ¹⁵ . More preferably, R ¹ is selected from the group consisting of hydrogen, halogen, Ci-C6alkyl, Ci-C6fluoroalkyl, -OR ⁷ and -N(R ^7a ) ₂ . Even more preferably, R ¹ is selected from the group consisting of hydrogen, Ci-C6alkyl, -OR ⁷ and -N(R ^7a ) ₂ . Even more preferably still, R ¹ is hydrogen or Ci-C6alkyl. Yet even more preferably still, R ¹ is hydrogen or methyl. Most preferably R ¹ is hydrogen.

Preferably, R ² is selected from the group consisting of hydrogen, Ci-C6alkyl and Ci-C6fluoroalkyl. More preferably, R ² is hydrogen or Ci-C6alkyl. Even more preferably, R ² is hydrogen or methyl. Most preferably R ² is hydrogen.

Preferably, when R ¹ is selected from the group consisting of -OR ⁷ , -NHS(0) ₂ R ¹⁵ , -NHC(0)R ¹⁵ , - NHC(0)0R ¹⁵ , -NHC(0)NR ¹⁶ R ¹⁷ , -N(R ^7a ) ₂ and -S(0) _r R ¹⁵ , then R ² is selected from the group consisting of hydrogen and methyl.

Preferably when, R ¹ and R ² together with the carbon atom to which they are attached form a C3- C6cycloalkyl ring or a 3- to 6- membered heterocyclyl, which comprises 1 or 2 heteroatoms individually selected from N and O then R ¹ and R ² together with the carbon atom to which they are attached form a C3-C6cycloalkyl ring. In this case more preferably, R ¹ and R ² together with the carbon atom to which they are attached form a cyclopropyl ring. In another embodiment R ¹ is methyl and R ² is hydrogen.

In another embodiment R ¹ is methyl and R ² is methyl.

In a preferred embodiment R ¹ and R ² are hydrogen.

Q is (CR ^1a R ^2b )m. m is 0, 1 , 2 or 3. Preferably, m is 0,1 or 2. More preferably, m is 0 or 1 . Most preferably, m is 1 .

Each R ^1a and R ^2b are independently selected from the group consisting of hydrogen, halogen, Ci- Cealkyl, Ci-C ₆ haloalkyl, -OH, -OR ⁷ , -OR ^15a , -NH ₂ , -NHR ⁷ , -NHR ^15a , -N(R ⁶ )CHO, -NR ^7b R ^7c and -S(0) _r R ¹⁵ .

Preferably, each R ^1a and R ^2b are independently selected from the group consisting of hydrogen, halogen, Ci-C6alkyl, Ci-C6fluoroalkyl, -OH, -NH ₂ and -NHR ⁷ . More preferably, each R ^1a and R ^2b are independently selected from the group consisting of hydrogen, Ci-C6alkyl, -OH and -NH ₂ . Even more preferably, each R ^1a and R ^2b are independently selected from the group consisting of hydrogen, methyl, -OH and -NH ₂ . Even more preferably still, each R ^1a and R ^2b are independently selected from the group consisting of hydrogen and methyl. Most preferably R ^1a and R ^2b are hydrogen.

In another embodiment each R ^1a and R ^2b are independently selected from the group consisting of hydrogen and Ci-C6alkyl.

Alternatively, each R ^1a and R ^2b together with the carbon atom to which they are attached form a C3-C6cycloalkyl ring or a 3- to 6- membered heterocyclyl, which comprises 1 or 2 heteroatoms individually selected from N and O. Preferably, each R ^1a and R ^2b together with the carbon atom to which they are attached form a C3-C6cycloalkyl ring. More preferably, each R ^1a and R ^2b together with the carbon atom to which they are attached form a cyclopropyl ring.

Preferably, R ³ , R ⁴ and R ⁵ are independently selected from the group consisting of hydrogen, Ci- Cealkyl, Ci-C6fluoroalkyl, Ci-C6fluoroalkoxy, Ci-C6alkoxy, C3-C6cycloalkyl and -N(R ⁶ ) ₂ . More preferably, R ³ , R ⁴ and R ⁵ are independently selected from the group consisting of hydrogen, Ci-C6alkyl and Ci- Cealkoxy. Even more preferably, R ³ , R ⁴ and R ⁵ are independently selected from the group consisting of hydrogen and Ci-C6alkyl. Even more preferably still, R ³ , R ⁴ and R ⁵ are independently selected from the group consisting of hydrogen and methyl. Most preferably, R ³ , R ⁴ and R ⁵ are hydrogen.

Preferably, each R ⁶ is independently selected from hydrogen and methyl.

Preferably, each R ⁷ is independently selected from the group consisting of Ci-C6alkyl, -C(0)R ¹⁵ and - C(0)NR ¹⁶ R ¹⁷ . More preferably, each R ⁷ is Ci-C6alkyl. Most preferably, each R ⁷ is methyl.

Preferably, each R ^7a is independently -C(0)R ¹⁵ or -C(0)NR ¹⁶ R ¹⁷ .

Preferably, R ^7b and R ^7c are independently selected from the group consisting of Ci-C6alkyl, - C(0)R ¹⁵ and -C(0)NR ¹⁶ R ¹⁷ . More preferably, R ^7b and R ^7c are Ci-C6alkyl. Most preferably, R ^7b and R ^7c are methyl.

Alternatively, R ^7b and R ^7c together with the nitrogen atom to which they are attached form a 4- to 6-membered heterocyclyl ring which optionally comprises one additional heteroatom individually selected from N, O and S. Preferably, R ^7b and R ^7c together with the nitrogen atom to which they are attached form a 5- to 6-membered heterocyclyl ring which optionally comprises one additional heteroatom individually selected from N and O. More preferably, R ^7b and R ^7c together with the nitrogen atom to which they are attached form an pyrrolidyl, oxazolidinyl, imidazolidinyl, piperidyl, piperazinyl or morpholinyl group. A is preferably selected from the group consisting of of pyridinone, pyridazinone, pyrimidinone, pyrazinone and triazinone, more preferably pyridinone, pyridazinone, pyrimidinone and pyrazinone. Most preferably A is pyridinone or pyridazinone.

Examples of A are Al to AXXXI.

p is 1 , 2 or 3 and the maximum value for p depends on the available carbon atoms in the ring. Preferably p is 0, 1 or 2, more preferably 0 or 1 , most preferably 0. Preferably, when p is 1 or 2, each R ⁸ is independently selected from the group consisting of halogen, nitro, cyano, -NH ₂ , -NHR ⁷ , -N(R ⁷ ) ₂ , -OH, -OR ⁷ , -S(0) _r R ¹⁵ , -NR ⁶ S(0) ₂ R ¹⁵ , -C(0)OR ¹⁰ , - C(0)R ¹⁵ , -C(0)NR ¹⁶ R ¹⁷ , -S(0) ₂ NR ¹⁶ R ¹⁷ , Ci-C ₆ alkyl, Ci-C ₆ haloalkyl, Cs-Cecycloalkyl, Ci-C ₃ alkoxyCi- C3alkyl-, hydroxyCi-Cealkyl-, Ci-C3alkoxyCi-C3alkoxy-, Ci-C6haloalkoxy, phenyl and a 6- membered heteroaryl, which comprises 1 or 2 nitrogen atoms, and wherein said phenyl or heteroaryl are optionally substituted by 1 or 2 R ⁹ substituents, which may be the same or different.

More preferably, when p is 1 or 2, each R ⁸ is independently selected from the group consisting of halogen, nitro, cyano, -NH ₂ , -NHR ⁷ , -N(R ⁷ ) ₂ , -OH, -OR ⁷ , -S(0) _r R ¹⁵ , -NR ⁶ S(0) ₂ R ¹⁵ , -C(0)OR ¹⁰ , - C(0)R ¹⁵ , -C(0)NR ¹⁶ R ¹⁷ , -S(0) ₂ NR ¹⁶ R ¹⁷ , Ci-C ₆ alkyl, Ci-C ₆ haloalkyl, Cs-Cecycloalkyl, Ci-C ₆ alkoxy, hydroxyCi-Cealkyl-, Ci-C6haloalkoxy and a 6- membered heteroaryl, which comprises 1 or 2 nitrogen atoms, and wherein said heteroaryl is optionally substituted by 1 R ⁹ substituent.

Even more preferably, when p is 1 or 2, each R ⁸ is independently selected from the group consisting of halogen, nitro, cyano, -NH ₂ , -NHR ⁷ , -N(R ⁷ ) ₂ , -OH, -OR ⁷ , -S(0) _r R ¹⁵ , -NR ⁶ S(0) ₂ R ¹⁵ , - C(0)OR ¹⁰ , -C(0)R ¹⁵ , -C(0)NR ¹⁶ R ¹⁷ , -S(0) ₂ NR ¹⁶ R ¹⁷ , Ci-C ₆ alkyl and Ci-C ₆ haloalkyl.

Even more preferably still, when p is 1 or 2, each R ⁸ is independently selected from the group consisting of chloro, fluoro, cyano, -NH ₂ , -NMe ₂ , -OH, -OMe, -S(0) ₂ Me, -C(0)0Me, -C(0)0H, -C(0)Me, -C(0)NH ₂ , -C(0)NHMe, -C(0)NMe ₂ , methyl and trifluoromethyl.

Most preferably, when p is 1 or 2, each R ⁸ is independently selected from the group consisting of chloro, fluoro, cyano, -NH ₂ , -NMe ₂ , -OMe, -S(0) ₂ Me, -C(0)NHMe, -C(0)NMe ₂ , methyl and trifluoromethyl.

Preferably when p is 3, then each R ⁸ is independently selected from the group consisting of chloro, fluoro, cyano, -S(0) _r R ¹⁵ , -C(0)NR ¹⁶ R ¹⁷ , -S(0) ₂ NR ¹⁶ R ¹⁷ , methyl, methoxy and trifluoromethyl. More preferably, when p is 3 then each R ⁸ is independently selected from the group consisting cyano, - S(0)rR ¹⁵ , -C(0)NR ¹⁶ R ¹⁷ , -S(0) ₂ NR ¹⁶ R ¹⁷ , methyl and methoxy. Even more preferably still, when p is 3, then each R ⁸ is independently selected from the group consisting of -C(0)NR ¹⁶ R ¹⁷ , methyl and methoxy.

Preferably, each R ⁹ is independently selected from the group consisting of halogen, cyano, - N(R ⁶ ) ₂ , Ci-C ₄ alkyl, Ci-C ₄ alkoxy, Ci-C ₄ haloalkyl and Ci-C ₄ haloalkoxy. More preferably, each R ⁹ is independently selected from the group consisting of halogen, Ci-C ₄ alkyl, Ci-C ₄ alkoxy and Ci- C ₄ haloalkyl. Even more preferably, each R ⁹ is independently selected from the group consisting of halogen and Ci-C ₄ alkyl.

X is selected from the group consisting of C3-C6cycloalkyl, phenyl, a 5- or 6- membered heteroaryl, which comprises 1 , 2, 3 or 4 heteroatoms individually selected from N, O and S, and a 4- to 6- membered heterocyclyl, which comprises 1 , 2 or 3 heteroatoms individually selected from N, O and S, and wherein said cycloalkyl, phenyl, heteroaryl or heterocyclyl moieties are optionally substituted by 1 or 2 substituents, which may be the same or different, selected from R ⁹ , and wherein the aforementioned CR ¹ R ² , Q and Z moieties may be attached at any position of said cycloalkyl, phenyl, heteroaryl or heterocyclyl moieties.

Preferably, X is selected from the group consisting of phenyl and a 4- to 6- membered heterocyclyl, which comprises 1 or 2 heteroatoms individually selected from N and O, and wherein said phenyl or heterocyclyl moieties are optionally substituted by 1 or 2 substituents, which may be the same or different, selected from R ⁹ , and wherein the aforementioned CR ¹ R ² , Q and Z moieties may be attached at any position of said phenyl or heterocyclyl moieties.

More preferably, X is a 4- to 6- membered heterocyclyl, which comprises 1 or 2 heteroatoms individually selected from N and O, and wherein said heterocyclyl moieties is optionally substituted by 1 or 2 substituents, which may be the same or different, selected from R ⁹ , and wherein the aforementioned CR ¹ R ² , Q and Z moieties may be attached at any position of said heterocyclyl moiety.

In one embodiment, X is a 5-membered heterocyclyl, which comprises 1 heteroatom, wherein said heteroatom is N, and wherein the aforementioned CR ¹ R ² , Q and Z moieties may be attached at any position of said heterocyclyl moiety. Preferably, X is a 5-membered heterocyclyl, which comprises 1 heteroatom, wherein said heteroatom is N, and wherein the aforementioned CR ¹ R ² and Q moieties are attached adjacent to the N atom and the Z moiety is attached to the N atom.

In another embodiment, X is phenyl optionally substituted by 1 or 2 substituents, which may be the same or different, selected from R ⁹ , and wherein the aforementioned CR ¹ R ² , Q and Z moieties may be attached at any position of said phenyl moiety. Preferably, X is phenyl and the aforementioned CR ¹ R ² and Q moieties are attached in a postion para to the Z moiety.

n is 0 or 1 . Preferably, n is 0.

Preferably, Z is selected from the group consisting of -C(0)OR ¹⁰ , -C(0)NH0R ¹¹ , - 0C(0)NH0R ¹¹ , -NR ⁶ C(0)NH0R ¹¹ , -C(0)NHS(0) ₂ R ¹² , -0C(0)NHS(0) ₂ R ¹² , -NR ⁶ C(0)NHS(0) ₂ R ¹² , - S(0) ₂ 0R ¹⁰ , -0S(0) ₂ 0R ¹⁰ , -NR ⁶ S(0) ₂ 0R ¹⁰ , -NR ⁶ S(0)OR ¹⁰ , -NHS(0) ₂ R ¹⁴ , -S(0)OR ¹⁰ , -OS(0)OR ¹⁰ , - S(0) ₂ NHC(0)R ¹⁸ , -S(0) ₂ NHS(0) ₂ R ¹² , -0S(0) ₂ NHS(0) ₂ R ¹² , -0S(0) ₂ NHC(0)R ¹⁸ , -NR ⁶ S(0) ₂ NHC(0)R ¹⁸ , -N(0H)C(0)R ¹⁵ , -0NHC(0)R ¹⁵ , -NR ⁶ S(0) ₂ NHS(0) ₂ R ¹² , -P(0)(R ¹³ )(OR ¹⁰ ), -P(0)H(OR ¹⁰ ), -

0P(0)(R ¹³ )(0R ¹ °) and -NR ⁶ P(0)(R ¹³ )(OR ¹⁰ ).

More preferably, Z is selected from the group consisting of -C(0)OR ¹⁰ , -C(0)NH0R ¹¹ , - C(0)NHS(0) ₂ R ¹² , -S(0) ₂ 0R ¹⁰ , -0S(0) ₂ 0R ¹⁰ , -NR ⁶ S(0) ₂ 0R ¹⁰ , -NHS(0) ₂ R ¹⁴ , -S(0)OR ¹⁰ and - P(0)(R ¹³ )(OR ¹⁰ ).

Even more preferably Z is selected from the group consisting of -C(0)OR ¹⁰ , -C(0)NHS(0) ₂ R ¹² , -S(0) ₂ 0R ¹⁰ , and -P(0)(R ¹³ )(OR ¹⁰ ).

Even more preferably still Z is selected from the group consisting of -C(0)0H, -C(0)0CH3, - C(0)0CH ₂ CH ₃ , -C(0)0CH(CH ₃ ) ₂ , -C(0)0C(CH ₃ ) ₃ , -C(0)0CH ₂ C ₆ H ₅ , -C(0)0C ₆ H ₅ , -C(0)NHS(0) ₂ CH ₃ , - S(0) ₂ 0H, -P(0)(0H)( OCH ₂ CH ₃ ) and -P(0)(0CH ₂ CH ₃ )(0CH ₂ CH ₃ ).

Most preferably Z is -C(0)0H or -S(0) ₂ 0H.

Preferably, R ¹⁰ is selected from the group consisting of hydrogen, Ci-C6alkyl, phenyl and benzyl. More preferably, R ¹⁰ is selected from the group consisting of hydrogen and Ci-C6alkyl. Most preferably, R ¹⁰ is hydrogen.

Preferably, R ¹¹ is selected from the group consisting of hydrogen, Ci-C6alkyl and phenyl. More preferably, R ¹¹ is selected from the group consisting of hydrogen and Ci-C6alkyl. Even more preferably, R ¹¹ is Ci-C6alkyl. Most preferably, R ¹¹ is methyl.

Preferably, R ¹² is selected from the group consisting of Ci-C6alkyl, Ci-C6haloalkyl, Ci-C6alkoxy, -OH, - N(R ⁶ ) ₂ and phenyl. More preferably, R ¹² is selected from the group consisting of Ci-C6alkyl, Ci- Cehaloalkyl and -N(R ⁶ ) ₂ . Even more preferably, R ¹² is selected from the group consisting of methyl, - N(Me) ₂ and trifluoromethyl. Most preferably, R ¹² is methyl. Preferably R ¹³ is selected from the group consisting of -OH, Ci-C6alkyl and Ci-C6alkoxy. More preferably, R ¹³ is selected from the group consisting of -OH and Ci-C6alkoxy. Even more preferably, R ¹³ is selected from the group consisting of -OH, methoxy and ethoxy. Most preferably, R ¹³ is -OH.

Preferably, R ¹⁴ is trifluoromethyl.

Preferably, R ¹⁵ is selected from the group consisting of Ci-C6alkyl and phenyl. More preferably, R ¹⁵ is Ci-C6alkyl. Most preferably R ¹⁵ is methyl.

Preferably, R ^15a is phenyl optionally substituted by 1 R ⁹ substituent. More preferably, R ^15a is phenyl.

R ¹⁶ and R ¹⁷ are independently selected from the group consisting of hydrogen and Ci-C6alkyl. Preferably, R ¹⁶ and R ¹⁷ are independently selected from the group consisting of hydrogen and methyl. Alternatively, R ¹⁶ and R ¹⁷ together with the nitrogen atom to which they are attached form a 4- to 6- membered heterocyclyl ring which optionally comprises one additional heteroatom individually selected from N, O and S. Preferably, R ¹⁶ and R ¹⁷ together with the nitrogen atom to which they are attached form a 5- to 6-membered heterocyclyl ring which optionally comprises one additional heteroatom individually selected from N and O. More preferably, R ¹⁶ and R ¹⁷ together with the nitrogen atom to which they are attached form an pyrrolidyl, oxazolidinyl, imidazolidinyl, piperidyl, piperazinyl or morpholinyl group.

Preferably, R ¹⁸ is selected from the group consisting of hydrogen, Ci-C6alkyl, Ci-C6haloalkyl, Ci-C6alkoxy, -N(R ⁶ )2 and phenyl. More preferably, R ¹⁸ is selected from the group consisting of hydrogen, Ci-C6alkyl and Ci-C6haloalkyl. Further more preferably, R ¹⁸ is selected from the group consisting of Ci- C6alkyl and Ci-C6haloalkyl. Most preferably, R ¹⁸ is methyl or trifluoromethyl.

Preferably R ³⁰ is selected from the group consisting Ci-C6alkyl, Ci-C6haloalkyl, C3-C6cycloalkyl, C3- C6cycloalkylCi-C3alkyl-, C2-C6alkenyl, C2-C6alkynyl, Ci-C3alkoxyCi-C3alkyl-, Ci-C6alkoxy, and hydroxyCi-C6alkyl-, more preferably Ci-C6alkyl, Ci-C6haloalkyl, C3-C6cycloalkylCi-C3alkyl-, C2- C6alkenyl, C2-C6alkynyl, Ci-C3alkoxyCi-C3alkyl-, and hydroxyCi-Cealkyl-, even more preferably Ci- Cealkyl, C2-C6alkynyl, and Ci-C3alkoxyCi-C3alkyl-, even still more preferably Ci-C6alkyl and most preferably methyl.

Preferably, r is 0 or 2.

In a set of preferred embodiments, in a compound according to formula (I) of the invention,

R ¹ is hydrogen or Ci-C6alkyl;

R ² is hydrogen or methyl;

Q is (CR ^1a R ^2b ) _m ;

m is 0,1 or 2;

R ^1a and R ^2b are independently selected from the group consisting of hydrogen, Ci-C6alkyl, -OH and -NH2;

R ³ , R ⁴ and R ⁵ are independently selected from the group consisting of hydrogen and Ci-C6alkyl; each R ⁶ is independently selected from hydrogen and methyl;

each R ⁷ is Ci-C6alkyl;

A is selected from the group consisting of pyridinone, pyridazinone, pyrimidinone, pyrazinone and triazinone;

P is 0 or 1 each R ⁸ is independently selected from the group consisting of chloro, fluoro, cyano, -NH ₂ , - NMe ₂ , -OH, -OMe, -S(0) ₂ Me, -C(0)0Me, -C(0)0H, -C(0)Me, -C(0)NH ₂ , -C(0)NHMe, - C(0)NMe ₂ , methyl and trifluoromethyl

n is 0;

Z is selected from the group consisting of -C(0)OR ¹⁰ , -C(0)NHS(0) ₂ R ¹² , -S(0) ₂ OR ¹⁰ , and - P(0)(R ¹³ )(OR ¹⁰ );

R ¹⁰ is selected from the group consisting of hydrogen, Ci-C6alkyl, phenyl and benzyl;

R ¹² is selected from the group consisting of Ci-C6alkyl, Ci-C6haloalkyl and -N(R ⁶ ) ₂ ;

R ¹³ is selected from the group consisting of -OH and Ci-C6alkoxy;

R ¹⁵ is Ci-Cealkyl;

R ¹⁶ and R ¹⁷ are independently selected from the group consisting of hydrogen and methyl;

R ³⁰ is Ci-C6alkyl; and

r is 0 or 2.

More preferably,

R ¹ is hydrogen or methyl;

R ² is hydrogen or methyl;

Q is (CR ^1a R ^2b ) _m ;

m is 1 or 2;

R ^1a and R ^2b are independently selected from the group consisting of hydrogen and methyl;

R ³ , R ⁴ and R ⁵ are independently selected from the group consisting of hydrogen and methyl;

A is selected from the group consisting of pyridinone and pyridazinone;

each R ⁸ is independently selected from the group consisting of chloro, fluoro, cyano, -NH ₂ , -

NMe ₂ , -OMe, -S(0) ₂ Me, -C(0)NHMe, -C(0)NMe ₂ , methyl and trifluoromethyl;

n is 0;

R ³⁰ is methyl; and

Z is selected from the group consisting of -C(0)0H, -C(0)0CH3, -C(0)0CH ₂ CH3, - C(0)0CH(CH ₃ ) ₂ , -C(0)0C(CH ₃ )3, -C(0)0CH ₂ C ₆ H ₅ , -C(0)0C ₆ H ₅ , -C(0)NHS(0) ₂ CH ₃ , - S(0) ₂ 0H, -P(0)(0H)( OCH ₂ CH ₃ ) and -R(0)(OOH ₂ OH ₃ )(OOH ₂ OH ₃ ).

There is also provided a process for the preparation of compounds of formula (I):

(I) wherein Q, Z, X, n, R ¹ , R ² , R ³ , R ⁴ , R ⁵ and

A are as defined herein; said process comprising

(i) either

(a) reacting a compound of formula (H) A— Hal formula (H)

wherein

A is as defined herein and Hal is a halogen or pseudo halogen, with a compound of formula (J)

wherein

R ³ , R ⁴ and R ⁵ are as defined herein and M’ is an organostannane or an organoborane (e.g organoboronic acid, organoboronic ester or organ otrifluoro borate), in the presence of a palladium catalyst, to give a compound of formula (X)

formula (X )

or

(b) reacting a compound of formula (K)

formula (K)

wherein R ³ , R ⁴ and R ⁵ are as defined herein and Hal is a halogen or pseudo halogen, with a compound of formula (L)

A— M' formula (L)

wherein

A is as defined herein and M’ is an organostannane or an organoborane (e.g organoboronic acid, organoboronic ester or organotrifluoroborate), in the presence of a palladium catalyst, to give a compound of formula (X);

(ii) reacting a compound of formula (X) with an alkylating agent of formula (W) formula (W)

wherein R ¹ , R ² , Q, X, Z and n are as defined herein, and LG is a suitable leaving group, in an inert solvent or mixture of inert solvents, at a temperature of from -78 °C to 150 °C, to give a compound of formula (I);

(iii) optionally,

partially or fully hydrolysing a compound of formula (I) in the presence of a suitable acid.

According to the invention there is also provided the use of a compound of formula (J) as defined herein, in a process for the manufacture of a compound of formula (I) as defined herein. Preferably, in a compound of formula (J) M’ is an organostannane, organoboronic acid, organoboronic ester or organotrifluoroborate. More preferably, in a compound of formula (J) M’ is an organostannane. Most preferably, in a compound of formula (J) M’ is tributylstannane.

In another embodiment of the invention there is also provided the use of a compound of formula (X) as defined herein, in a process for the manufacture of a compound of formula (I) as defined herein.

Compounds of formula (I) may exist/be manufactured in‘procidal form’, wherein they comprise a group‘G’. Such compounds are referred to herein as compounds of formula (l-IV).

G is a group which may be removed in a plant by any appropriate mechanism including, but not limited to, metabolism and chemical degradation to give a compound of formula (l-l), (l-ll) or (l-lll) wherein Z contains an acidic proton, for example see the scheme below:

Whilst such G groups may be considered as‘procidal’, and thus yield active herbicidal compounds once removed, compounds comprising such groups may also exhibit herbicidal activity in their own right. In such cases in a compound of formula (l-IV), Z-G may include but is not limited to, any one of (G1) to (G7) below and E indicates the point of attachment to the remaining part of a compound of formula (I): G is C

wherein said phenyl moiety is optionally substituted by 1 to 5 substituents independently selected from halo, cyano, nitro, Ci-C6alkyl, Ci-C6haloalkyl or Ci-C6alkoxy.

R ¹⁹ is Ci-C6alkyl or phenyl,

R ²⁰ is hydroxy, Ci-C6alkyl, Ci-C6alkoxy or phenyl,

R ²¹ is hydrogen or methyl,

R ²² is hydrogen or methyl,

R ²³ is hydrogen or Ci-C6alkyl.

The compounds in Tables 1 to 65 below illustrate the compounds of the invention. The skilled person would understand that the compounds of formula (I) may exist as an agronomically acceptable salt, a zwitterion or an agronomically acceptable salt of a zwitterion as described hereinbefore. Table 1 :

This table discloses 53 specific compounds of the formula (T-1):

wherein m, Q, R ³ , R ⁴ , R ⁵ and Z are as defined in Table 1 , R ¹ and R ² are hydrogen and n is 0.

Table 2:

This table discloses 49 specific compounds of the formula (T-2):

wherein m, Q, R ³ , R ⁴ , R ⁵ and Z are as defined in Table 2, R ¹ and R ² are hydrogen and n is 0.

Table 3:

This table discloses 49 specific compounds of the formula (T-3):

wherein m, Q, R ³ , R ⁴ , R ⁵ and Z are as defined in Table 3, R ¹ and R ² are hydrogen and n is 0.

Table 4:

This table discloses 53 specific compounds of the formula (T-4):

wherein m, Q, R ³ , R ⁴ , R ⁵ and Z are as defined above in Table 1 , R ¹ and R ² are hydrogen and n is 0.

Table 5:

This table discloses 49 specific compounds of the formula (T-5):

wherein m, Q, R ³ , R ⁴ , R ⁵ and Z are as defined above in Table 2, R ¹ and R ² are hydrogen and n is 0. Table 6:

This table discloses 49 specific compounds of the formula (T-6):

wherein m, Q, R ³ , R ⁴ , R ⁵ and Z are as defined above in Table 3, R ¹ and R ² are hydrogen and n is 0.

Table 7:

This table discloses 53 specific compounds of the formula (T-7):

wherein m, Q, R ³ , R ⁴ , R ⁵ and Z are as defined above in Table 1 , R ¹ and R ² are hydrogen and n is 0. Table 8:

This table discloses 49 specific compounds of the formula (T-8):

wherein m, Q, R ³ , R ⁴ , R ⁵ and Z are as defined above in Table 2, R ¹ and R ² are hydrogen and n is 0. Table 9:

This table discloses 49 specific compounds of the formula (T-9):

wherein m, Q, R ³ , R ⁴ , R ⁵ and Z are as defined above in Table 3, R ¹ and R ² are hydrogen and n is 0. Table 10:

This table discloses 53 specific compounds of the formula (T-10):

(T-10) wherein m, Q, R ³ , R ⁴ , R ⁵ and Z are as defined above in Table 1 , R ¹ and R ² are hydrogen and n is 0.

Table 11 :

This table discloses 49 specific compounds of the formula (T-11):

(T-11)

wherein m, Q, R ³ , R ⁴ , R ⁵ and Z are as defined above in Table 2, R ¹ and R ² are hydrogen and n is 0.

Table 12:

This table discloses 49 specific compounds of the formula (T-12):

(T-12)

wherein m, Q, R ³ , R ⁴ , R ⁵ and Z are as defined above in Table 3, R ¹ and R ² are hydrogen and n is 0. Table 13:

This table discloses 53 specific compounds of the formula (T-13):

wherein m, Q, R ³ , R ⁴ , R ⁵ and Z are as defined above in Table 1 , R ¹ and R ² are hydrogen and n is 0. Table 14:

This table discloses 49 specific compounds of the formula (T-14):

Table 15:

This table discloses 49 specific compounds of the formula (T-15):

Table 16:

This table discloses 53 specific compounds of the formula (T-16):

wherein m, Q, R ³ , R ⁴ , R ⁵ and Z are as defined above in Table 1 , R ¹ and R ² are hydrogen and n is 0. Table 17:

This table discloses 49 specific compounds of the formula (T-17):

wherein m, Q, R ³ , R ⁴ , R ⁵ and Z are as defined above in Table 2, R ¹ and R ² are hydrogen and n is 0.

Table 18:

This table discloses 49 specific compounds of the formula (T-18):

wherein m, Q, R ³ , R ⁴ , R ⁵ and Z are as defined above in Table 3, R ¹ and R ² are hydrogen and n is 0.

Table 19:

This table discloses 53 specific compounds of the formula (T-19):

wherein m, Q, R ³ , R ⁴ , R ⁵ and Z are as defined above in Table 1 , R ¹ and R ² are hydrogen and n is 0.

Table 20:

This table discloses 49 specific compounds of the formula (T-20):

wherein m, Q, R ³ , R ⁴ , R ⁵ and Z are as defined above in Table 2, R ¹ and R ² are hydrogen and n is 0.

Table 21 :

This table discloses 49 specific compounds of the formula (T-21):

wherein m, Q, R ³ , R ⁴ , R ⁵ and Z are as defined above in Table 3, R ¹ and R ² are hydrogen and n is 0. Table 22:

This table discloses 53 specific compounds of the formula (T-22):

wherein m, Q, R ³ , R ⁴ , R ⁵ and Z are as defined above in Table 1 , R ¹ and R ² are hydrogen and n is 0.

Table 23:

This table discloses 49 specific compounds of the formula (T-23):

wherein m, Q, R ³ , R ⁴ , R ⁵ and Z are as defined above in Table 2, R ¹ and R ² are hydrogen and n is 0.

Table 24:

This table discloses 49 specific compounds of the formula (T-24):

wherein m, Q, R ³ , R ⁴ , R ⁵ and Z are as defined above in Table 3, R ¹ and R ² are hydrogen and n is 0. Table 25:

This table discloses 53 specific compounds of the formula (T-25):

wherein m, Q, R ³ , R ⁴ , R ⁵ and Z are as defined above in Table 1 , R ¹ and R ² are hydrogen and n is 0.

Table 26:

This table discloses 49 specific compounds of the formula (T-26):

wherein m, Q, R ³ , R ⁴ , R ⁵ and Z are as defined above in Table 2, R ¹ and R ² are hydrogen and n is 0.

Table 27:

This table discloses 49 specific compounds of the formula (T-27):

wherein m, Q, R ³ , R ⁴ , R ⁵ and Z are as defined above in Table 3, R ¹ and R ² are hydrogen and n is 0. Table 28:

This table discloses 53 specific compounds of the formula (T-28):

(T-28)

wherein m, Q, R ³ , R ⁴ , R ⁵ and Z are as defined above in Table 1 , R ¹ and R ² are hydrogen and n is 0. Table 29:

This table discloses 49 specific compounds of the formula (T-29):

(T-29)

wherein m, Q, R ³ , R ⁴ , R ⁵ and Z are as defined above in Table 2, R ¹ and R ² are hydrogen and n is 0.

Table 30:

This table discloses 49 specific compounds of the formula (T-30):

(T-30)

wherein m, Q, R ³ , R ⁴ , R ⁵ and Z are as defined above in Table 3, R ¹ and R ² are hydrogen and n is 0.

Table 31:

This table discloses 53 specific compounds of the formula (T-31):

wherein m, Q, R ³ , R ⁴ , R ⁵ and Z are as defined above in Table 1 , R ¹ and R ² are hydrogen and n is 0. Table 32:

This table discloses 49 specific compounds of the formula (T-32):

wherein m, Q, R ³ , R ⁴ , R ⁵ and Z are as defined above in Table 2, R ¹ and R ² are hydrogen and n is 0.

Table 33:

This table discloses 49 specific compounds of the formula (T-33):

wherein m, Q, R ³ , R ⁴ , R ⁵ and Z are as defined above in Table 3, R ¹ and R ² are hydrogen and n is 0.

Table 34:

This table discloses 53 specific compounds of the formula (T-34):

wherein m, Q, R ³ , R ⁴ , R ⁵ and Z are as defined above in Table 1 , R ¹ and R ² are hydrogen and n is 0.

Table 35:

This table discloses 49 specific compounds of the formula (T-35):

wherein m, Q, R ³ , R ⁴ , R ⁵ and Z are as defined above in Table 2, R ¹ and R ² are hydrogen and n is 0. Table 36:

This table discloses 49 specific compounds of the formula (T-36):

wherein m, Q, R ³ , R ⁴ , R ⁵ and Z are as defined above in Table 3, R ¹ and R ² are hydrogen and n is 0.

Table 37:

This table discloses 53 specific compounds of the formula (T-37):

wherein m, Q, R ³ , R ⁴ , R ⁵ and Z are as defined above in Table 1 , R ¹ and R ² are hydrogen and n is 0.

Table 38:

This table discloses 49 specific compounds of the formula (T-38):

(T-38)

wherein m, Q, R ³ , R ⁴ , R ⁵ and Z are as defined above in Table 2, R ¹ and R ² are hydrogen and n is 0. Table 39:

This table discloses 49 specific compounds of the formula (T-39):

wherein m, Q, R ³ , R ⁴ , R ⁵ and Z are as defined above in Table 3, R ¹ and R ² are hydrogen and n is 0.

Table 40:

This table discloses 53 specific compounds of the formula (T-40):

wherein m, Q, R ³ , R ⁴ , R ⁵ and Z are as defined above in Table 1 , R ¹ and R ² are hydrogen and n is 0.

Table 41 :

This table discloses 49 specific compounds of the formula (T-41):

wherein m, Q, R ³ , R ⁴ , R ⁵ and Z are as defined above in Table 2, R ¹ and R ² are hydrogen and n is 0. Table 42:

This table discloses 49 specific compounds of the formula (T-42):

wherein m, Q, R ³ , R ⁴ , R ⁵ and Z are as defined above in Table 3, R ¹ and R ² are hydrogen and n is 0.

Table 43:

This table discloses 53 specific compounds of the formula (T-43):

(T-43)

wherein m, Q, R ³ , R ⁴ , R ⁵ and Z are as defined above in Table 1 , R ¹ and R ² are hydrogen and n is 0. Table 44:

This table discloses 49 specific compounds of the formula (T-44):

(T-44)

wherein m, Q, R ³ , R ⁴ , R ⁵ and Z are as defined above in Table 2, R ¹ and R ² are hydrogen and n is 0.

Table 45:

This table discloses 49 specific compounds of the formula (T-45):

(T-45)

wherein m, Q, R ³ , R ⁴ , R ⁵ and Z are as defined above in Table 3, R ¹ and R ² are hydrogen and n is 0. Table 46:

This table discloses 53 specific compounds of the formula (T-46):

wherein m, Q, R ³ , R ⁴ , R ⁵ and Z are as defined above in Table 1 , R ¹ and R ² are hydrogen and n is 0.

Table 47:

This table discloses 49 specific compounds of the formula (T-47):

wherein m, Q, R ³ , R ⁴ , R ⁵ and Z are as defined above in Table 2, R ¹ and R ² are hydrogen and n is 0.

Table 48:

This table discloses 49 specific compounds of the formula (T-48):

wherein m, Q, R ³ , R ⁴ , R ⁵ and Z are as defined above in Table 3, R ¹ and R ² are hydrogen and n is 0.

Table 49:

This table discloses 53 specific compounds of the formula (T-49):

(T-49)

wherein m, Q, R ³ , R ⁴ , R ⁵ and Z are as defined above in Table 1 , R ¹ and R ² are hydrogen and n is 0.

Table 50: This table discloses 49 specific compounds of the formula (T-50):

(T-50)

wherein m, Q, R ³ , R ⁴ , R ⁵ and Z are as defined above in Table 2, R ¹ and R ² are hydrogen and n is 0.

Table 51:

This table discloses 49 specific compounds of the formula (T-51):

(T-51)

wherein m, Q, R ³ , R ⁴ , R ⁵ and Z are as defined above in Table 3, R ¹ and R ² are hydrogen and n is 0.

Table 52:

This table discloses 53 specific compounds of the formula (T-52):

wherein m, Q, R ³ , R ⁴ , R ⁵ and Z are as defined above in Table 1 , R ¹ and R ² are hydrogen and n is 0. Table 53:

This table discloses 49 specific compounds of the formula (T-53):

wherein m, Q, R ³ , R ⁴ , R ⁵ and Z are as defined above in Table 2, R ¹ and R ² are hydrogen and n is 0.

Table 54:

This table discloses 49 specific compounds of the formula (T-54):

wherein m, Q, R ³ , R ⁴ , R ⁵ and Z are as defined above in Table 3, R ¹ and R ² are hydrogen and n is 0.

Table 55:

This table discloses 53 specific compounds of the formula (T-55):

wherein m, Q, R ³ , R ⁴ , R ⁵ and Z are as defined above in Table 1 , R ¹ and R ² are hydrogen and n is 0. Table 56:

This table discloses 49 specific compounds of the formula (T-56):

wherein m, Q, R ³ , R ⁴ , R ⁵ and Z are as defined above in Table 2, R ¹ and R ² are hydrogen and n is 0. Table 57:

This table discloses 49 specific compounds of the formula (T-57):

wherein m, Q, R ³ , R ⁴ , R ⁵ and Z are as defined above in Table 3, R ¹ and R ² are hydrogen and n is 0.

Table 58:

This table discloses 53 specific compounds of the formula (T-58):

wherein m, Q, R ³ , R ⁴ , R ⁵ and Z are as defined above in Table 1 , R ¹ and R ² are hydrogen and n is 0.

Table 59:

This table discloses 49 specific compounds of the formula (T-59):

wherein m, Q, R ³ , R ⁴ , R ⁵ and Z are as defined above in Table 2, R ¹ and R ² are hydrogen and n is 0. Table 60:

This table discloses 49 specific compounds of the formula (T-60):

wherein m, Q, R ³ , R ⁴ , R ⁵ and Z are as defined above in Table 3, R ¹ and R ² are hydrogen and n is 0. Table 61:

This table discloses 53 specific compounds of the formula (T-61):

(T-61)

wherein m, Q, R ³ , R ⁴ , R ⁵ and Z are as defined above in Table 1 , R ¹ and R ² are hydrogen and n is 0.

Table 62:

This table discloses 49 specific compounds of the formula (T-62):

(T-62)

wherein m, Q, R ³ , R ⁴ , R ⁵ and Z are as defined above in Table 2, R ¹ and R ² are hydrogen and n is 0.

Table 63:

This table discloses 49 specific compounds of the formula (T-63):

(T-63)

wherein m, Q, R ³ , R ⁴ , R ⁵ and Z are as defined above in Table 3, R ¹ and R ² are hydrogen and n is 0. Table 64:

This table discloses 17 specific compounds of the formula (T-64):

Wherein R ³ , R ⁴ , R ⁵ and R ⁸ are hydrogen.

Table 65:

This table discloses 17 specific compounds of the formula (T-65):

wherein R ³ , R ⁴ , R ⁵ and R ⁸ are hydrogen.

The compounds of the present invention may be prepared according to the following schemes in which the substituents m, n, r, R ¹ , R ² , R ³ , R ⁴ , R ⁵ , R ⁶ , R ⁷ , R ⁸ , R ⁹ , R ¹⁰ , R ¹¹ , R ¹² , R ¹³ , R ¹⁴ , R ¹⁵ , R ¹⁶ , R ¹⁷ , R ¹⁸ , R ^1a , R ^2b , Q, X and Z are as defined hereinbefore unless explicitly stated otherwise. The compounds of the preceeding Tables 1 to 65 may thus be obtained in an analogous manner.

The compounds of formula (I) may be prepared by the alkylation of compounds of formula (X), wherein R ³ , R ⁴ , R ⁵ and A are as defined for compounds of formula (I), with a suitable alkylating agent of formula (W), wherein n, R ¹ , R ² , Q, X and Z are as defined for compounds of formula (I) and LG is a suitable leaving group, for example, halide or pseudohalide such as triflate, mesylate or tosylate, in a suitable solvent at a suitable temperature, as described in reaction scheme 1 . Example conditions include stirring a compound of formula (X) with an alkylating agent of formula (W) in a solvent, or mixture of solvents, such as acetone, dichloromethane, dichloroethane, A/,A/-dimethylformamide, acetonitrile, 1 ,4-dioxane, water, acetic acid or trifluroacetic acid at a temperature between -78°C and 150°C. An alkylating agent of formula (W) may include, but is not limited to, bromoacetic acid, methyl bromoacetate, 3-bromopropionoic acid, methyl 3-bromopropionate, 2-bromo-A/-methoxyacetamide, sodium 2- bromoethanesulphonate, 2,2-dimethylpropyl 2-(trifluoromethylsulfonyloxy)ethanesulfonate, 2-bromo-A/- methanesulfonylacetamide, 3-bromo-A/-methanesulfonylpropanamide, dimethoxyphosphorylmethyl trifluoromethanesulfonate, dimethyl 3-bromopropylphosphonate, 3-chloro-2, 2-dimethyl-propanoic acid and diethyl 2-bromoethylphosphonate. Such alkylating agents and related compounds are either known in the literature or may be prepared by known literature methods. Compounds of formula (I) which may be described as esters of N- alkyl acids, which include, but are not limited to, esters of carboxylic acids, phosphonic acids, phosphinic acids, sulfonic acids and sulfinic acids, may be subsequently partially or fully hydrolysed by treament with a suitable reagent, for example, aqueous hydrochloric acid or trimethylsilyl bromide, in a suitable solvent at a suitable temperature between 0°C and 100°C.

Reaction scheme 1

formula (X)

formula (I) Additonally, compounds of formula (I) may be prepared by reacting compounds of formula (X), wherein R ³ , R ⁴ , R ⁵ , R ¹⁰ , R ¹¹ , R ¹³ and A are as defined for compounds of formula (I), with a suitably activated electrophilic alkene of formula (B), wherein R ¹ , R ² and R ^1a are as defined for compounds of formula (I) and Z is SO3R ¹¹ , P(0)(R ¹³ )(OR ¹⁰ ) or C(0)OR ¹⁰ , in a suitable solvent at a suitable temperature. Compounds of formula (B) are known in the literature, or may be prepared by known methods. Example reagents include, but are not limited to, acrylic acid, methacrylic acid, crotonic acid, 3,3-dimethylacrylic acid, methyl acrylate, ethene sulfonic acid, isopropyl ethylenesulfonate, 2,2-dimethylpropyl ethenesulfonate and dimethyl vinylphosphonate. The direct products of these reactions, which may be described as esters of N-alkyl acids, which include, but are not limited to, esters of carboxylic acids, phosphonic acids, phosphinic acids, sulfonic acids and sulfinic acids, may be subsequently partially or fully hydrolysed by treament with a suitable reagent in a suitable solvent at a suitable temperature, as described in reaction scheme 2.

Reaction scheme 2

formula (I), wherein formula (I), wherein formula (X)

m=1 , n=0 and m=1 , n=0 and

Z=S0 ₃ R ^{1 1} , P(0)(R ¹³ )(0R ¹⁰ ), Z=S0 ₃ H, P(0)(R ¹³ )(0H), C(0)0R ¹⁰ C(0)0H

In a related reaction compounds of formula (I), wherein Q is C(R ^1a R ^2b ), m is 1 , 2 or 3, n=0 and Z is SO3H, OSO3H or NR ⁶ SC>3H, may be prepared by the reaction of compounds of formula (X), wherein R ³ , R ⁴ , R ⁵ and A are as defined for compounds of formula (I), with a cyclic alkylating agent of formula (E), (F) or (AF), wherein Y is C(R ^1a R ^2b ), O or NR ⁶ and R ¹ , R ² , R ^1a and R ^2b are as defined for compounds of formula (I), in a suitable solvent at a suitable temperature, as described in reaction scheme 3. Suitable solvents and suitable temperatures are as previously described. An alkylating agent of formula (E) or (F) may include, but is not limited to, 1 ,3-propanesultone, 1 ,4-butanesultone, ethylenesulfate, 1 ,3-propylene sulfate and 1 ,2,3-oxathiazolidine 2,2-dioxide. Such alkylating agents and related compounds are either known in the literature or may be prepared by known literature methods. Reaction scheme 3

formula (E) or

Z = S0 ₃ H, OSO _g H or

formula (AF) NR ⁶ SO ₃ H

Where m=1 and

n=0 A compound of formula (I), wherein m is 0, n is 0 and Z is SO3H, may be prepared from a compound of formula (I), wherein m is 0, n is 0 and Z is C(0)OR ¹⁰ , by treatment with trimethylsilylchlorosulfonate in a suitable solvent at a suitable temperature, as described in reaction scheme 4. Preferred conditions include heating the carboxylate precursor in neat trimethylsilylchlorosulfonate at a temperature between

25°C and 150°C.

Reaction scheme 4

formula (I), wherein formula (I), wherein m=0, n=0 m=0, n=0

and Z=C(0)OR ^{1 0} and Z=S0 ₃ H Furthermore, compounds of formula (I) may be prepared by reacting compounds of formula (X), wherein R ³ , R ⁴ , R ⁵ and A are as defined for compounds of formula (I), with a suitable alcohol of formula (WW), wherein R ¹ , R ² , Q, X and Z are as defined for compounds of formula (I), under Mitsunobu-type conditions such as those reported by Petit et al, Tet. Lett. 2008, 49 (22), 3663. Suitable phosphines include triphenylphosphine, suitable azodicarboxylates include diisopropylazodicarboxylate and suitable acids include fluoroboric acid, triflic acid and bis(trifluoromethylsulfonyl)amine, as described in reaction scheme 5. Such alcohols are either known in the literature or may be prepared by known literature methods. Reaction scheme 5

Compounds of formula (I) may also be prepared by reacting compounds of formula (C), wherein Q, Z, X, R ¹ , R ² , R ³ , R ⁴ , R ⁵ and A are as defined for compounds of formula (I), with a hydrazine of formula (D) in a suitable solvent or mixture of solvents, in the presence of a suitable acid at a suitable temperature, between -78°C and 150°C, as described in reaction scheme 6. Suitable solvents, or mixtures thereof, include, but are not limited to, alcohols, such as methanol, ethanol and isopropanol, water, aqueous hydrochloric acid, aqueous sulfuric acid, acetic acid and trifluoroacetic acid. Hydrazine compounds of formula (D), for example 2,2-dimethylpropyl 2- hydrazinoethanesulfonate, are either known in the literature or may be prepared by known literature procedures.

Reaction scheme 6

formula (C)

R' = H, C ₁ -C ₄ alkyl, formula (I)

C C ₄ alkyl carbonyl Compounds of formula (C) may be prepared by reacting compounds of formula (G), wherein R ³ , R ⁴ , R ⁵ and A are as defined for compounds of formula (I), with an oxidising agent in a suitable solvent at a suitable temperature, between -78°C and 150°C, optionally in the presence of a suitable base, as described in reaction scheme 7. Suitable oxidising agents include, but are not limited to, bromine and suitable solvents include, but are not limited to alcohols such as methanol, ethanol and isopropanol. Suitable bases include, but are not limited to, sodium bicarbonate, sodium carbonate, potassium bicarbonate, potassium carbonate and potassium acetate. Similar reactions are known in the literature (for example Hufford, D. L; Tarbell, D. S.; Koszalka, T. R. J. Amer. Chem. Soc., 1952, 3014). Furans of formula (G) are known in the literature or may be prepared using literature methods. Example methods include, but are not limited to, transition metal cross-couplings such as Stille (for example Farina, V.; Krishnamurthy, V.; Scott, W. J. Organic Reactions, Vol. 50. 1997, and Gazzard, L. et al. J. Med. Chem., 2015, 5053), Suzuki-Miyaura (for example Ando, S.; Matsunaga, H.; Ishizuka, T. J. Org. Chem. 2017, 1266-1272, and Ernst, J. B.; Rakers, L.; Glorius, F. Synthesis, 2017, 260), Negishi (for example Yang, Y.; Oldenhius, N. J.; Buchwald, S. L. Angew. Chem. Int. Ed. 2013, 615, and Braendvang, M.; Gundersen, L. Bioorg. Med. Chem. 2005, 6360), and Kumada (for example Heravi, M. M.; Hajiabbasi, P. Monatsh. Chem., 2012, 1575). The coupling partners may be selected with reference to the specific cross-coupling reaction and target product. Transition metal catalysts, ligands, bases, solvents and temperatures may be selected with reference to the desired cross-coupling and are known in the literature. Cross-coupling reactions using pseudo halogens, including but not limited to, triflates, mesylates, tosylates and anisoles, may also be achieved under related conditions.

Reaction scheme 7

formula (G) R' = H, C ₁ -C ₄ alkyl,

C C ₄ alkyl carbonyl

In another approach a compound of formula (I), wherein Q, Z, X, R ¹ , R ² , R ³ , R ⁴ , R ⁵ and A are as defined for compounds of formula (I), may be prepared from a compound of formula (R) and an oxidant, in a suitable solvent at a suitable temperature, as outlined in reaction scheme 8. Example oxidants include, but are not limited to, 2,3-dichloro-5,6-dicyano-1 ,4-benzoquinone, tetrachloro-p- benzoquinone, potassium permanganate, manganese dioxide, 2,2,6,6-tetramethyl-1 -piperidinyloxy and bromine. Related reactions are known in the literature. Reaction scheme 8

formula (R) formula (I)

A compound of formula (R), wherein Q, Z, X, R ¹ , R ² , R ³ , R ⁴ , R ⁵ and A are as defined for compounds of formula (I), may be prepared from a compound of formula (S) and an organometallic of formula (T), which includes, but is not limited to, organomagnesium, organolithium, organocopper and organozinc reagents, in a suitable solvent at a suitable temperature, optionally in the presence of an additonal transition metal additive, as outlined in reaction scheme 9. Example conditions include treating a compound of formula (S) with a Grignard of formula (T), in the presence of 0.05-100% copper iodide, in a solvent such as tetrahydrofuran at a temperature between -78°C and 100°C.

Organometallics of formula (T) are known in the literature, or may be prepared by known literature methods. Compounds of formula (S) may be prepared by analogous reactions to those for the preparation of compounds of formula (I).

Reaction scheme 9

formula (S) formula (R)

Biaryl pyridazines of formula (X) are known in the literature or may be prepared using literature methods. Example methods include, but are not limited to, the transition metal cross-coupling of compounds of formula (H) and formula (J), or alternatively compounds of formula (K) and formula (L), in which compounds of formula (J) and formula (L) are either an organostannane, organoboronic acid or ester, organotrifluoroborate, organomagnesium, organocopper or organozinc, as outlined in reaction scheme 10. Hal is defined as a halogen or pseudo halogen, for example triflate, mesylate and tosylate. Such cross-couplings include Stille (for example Sauer, J.; Heldmann, D. K. Tetrahedron, 1998, 4297), Suzuki-Miyaura (for example Luebbers, T.; Flohr, A.; Jolidon, S.; David-Pierson, P.; Jacobsen, H.; Ozmen, L.; Baumann, K. Bioorg. Med. Chem. Lett.,

201 1 , 6554), Negishi (for example Imahori, T.; Suzawa, K.; Kondo, Y. Heterocycles, 2008, 1057), and Kumada (for example Heravi, M. M.; Hajiabbasi, P. Monatsh. Chem., 2012, 1575). The coupling partners may be selected with reference to the specific cross-coupling reaction and target product. Transition metal catalysts, ligands, bases, solvents and temperatures may be selected with reference to the desired cross-coupling and are known in the literature. Compounds of formula (K) are known in the literature, or may be prepared by known literature methods. Compounds of formula (H) are also known in the literature, or may be prepared by known methods (see for example Higuchi, H.; Hattori, M.; Ohmiya, S. Heterocycles (2000), 52(1), 253, Modak, A.; Rana, S.; Maiti, D. J. Org. Chem. (2015), 80(1), 296, Najib, A.; Tabuchi, S.; Hirano, K.; Miura, M. Heterocycles, (2016), 92(7), 1 187, Gazzard et al WO 2012080284 and Yi, X.; Chen, J.; Xu, X.; Ma, Y. Synth. Commun. 2017, 47(9), 872). A compound of formula (L) may be prepared from a compound of formual (H) by an analogous transformation to that described for the convernsion of a compound of formula (K) into a compound of formula (J), as decribed in the literature or by known literature methods.

Reaction scheme 10

An organometallic of formula (J), which is either an organostannane, organoboronic acid or ester, organotrifluoroborate, organomagnesium, organocopper or organozinc, may be prepared from a compound of formula (XX), wherein R ³ , R ⁴ and R ⁵ are as defined for compounds of formula (I), by metallation, as outlined in reaction scheme 1 1 . Similar reactions are known in the literature (for example Ramphal et al, WO2015153683, Unsinn et al., Organic Letters, 15(5), 1 128-1 131 ; 2013, Sadler et al., Organic & Biomolecular Chemistry, 12(37), 7318-7327; 2014. Alternatively, an organometallic of formula (J) may be prepared from compounds of formula (K), wherein R ³ , R ⁴ , R ⁵ are as defined for compounds of formula (I), and Hal is defined as a halogen or pseudo halogen, for example triflate, mesylate and tosylate, as described in scheme 9. Example conditions to prepare an organostannane of formula (J) include treatment of a compound of formula (K) with lithium tributyl tin in an appropriate solvent at an appropriate temperature (for example see WO 2010038465). Example conditions to prepare an organoboronic acid or ester of formula (J) include treatment of a compound of formula (K) with bis(pinacolato)diboron, in the presence of an appropriate transition metal catalyst, appropriate ligand, appropriate base, in an appropriate solvent at an appropriate temperature (for example KR 2015135626). Compounds of formula (K) and formula (XX) are either known in the literature or can be prepared by known methods. Reaction scheme 11

formula (K) formula (J) formula (XX)

In another approach, an organometallic of formula (J), in which M’ is either an organostannane or organoboronic acid or ester, may be prepared from a compound of formula (N) and a compound of formula (O), wherein R ³ , R ⁴ and R ⁵ are as defined for compounds of formula (I), as outlined in reaction scheme 12. Examples of such a reaction are known in the literature, for example, Helm et al., Org. and Biomed. Chem., 2006, 4 (23), 4278, Sauer et al., Eur. J. Org. Chem., 1998, 12, 2885, and Helm, M. D.; Moore, J. E.; Plant, A.; Harrity, J. P. A., Angew. Chem. Int. Ed., 2005, 3889. Compounds of formula (N) and formula (O) are known in the literature.

Reaction scheme 12

formula (N) formula (O) formula (J)

Compounds of formula (X), wherein R ³ , R ⁴ , R ⁵ and A are as previously defined, may be prepared from compounds of formula (P) and formula (O), in an appropriate solvent, at an appropriate temperature, as outlined in reaction scheme 13. Examples of such a reaction are known in the literature, for example, Sauer et al., Eur. J. Org. Chem., 1998, 12, 2885. Compounds of formula (P) are known in the literature, or may be prepared by known methods.

Reaction scheme 13

formula (P) formula (O) formula (X)

In a further approach a compound of formula (X), wherein R ³ , R ⁴ , R ⁵ and A are as defined for compounds of formula (I), may be prepared from compounds of formula (C) and hydrazine, in an appropriate solvent, at an appropriate temperature, as outlined in reaction scheme 14. This reaction may also optionally be performed in the presence of an acid, for example aqueous sulfuric acid or aqueous hydrochloric acid. Similar reactions are known in the literature (for example DE 102005029094, and Chen, B.; Bohnert, T.; Zhou, X.; Dedon, P. C. Chem. Res. Toxicol., 2004, 1406). Compounds of formula (C) may be prepared as previously outlined.

Reaction scheme 14

formula (C) formula (X)

R' = H, C1 -C4alkyl,

C1 -C4alkyl carbonyl

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

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

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

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

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

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

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

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

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

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

Emulsifiable concentrates:

active ingredient: 1 to 95 %, preferably 60 to 90 %

surface-active agent: 1 to 30 %, preferably 5 to 20 %

liquid carrier: 1 to 80 %, preferably 1 to 35 %

Dusts:

active ingredient: 0.1 to 10 %, preferably 0.1 to 5 %

solid carrier: 99.9 to 90 %, preferably 99.9 to 99 % Suspension concentrates:

active ingredient: 5 to 75 %, preferably 10 to 50 %

water: 94 to 24 %, preferably 88 to 30 %

surface-active agent: 1 to 40 %, preferably 2 to 30 %

Wettable powders:

active ingredient: 0.5 to 90 %, preferably 1 to 80 %

surface-active agent: 0.5 to 20 %, preferably 1 to 15 %

solid carrier: 5 to 95 %, preferably 15 to 90 %

Granules:

active ingredient: 0.1 to 30 %, preferably 0.1 to 15 %

solid carrier: 99.5 to 70 %, preferably 97 to 85 %

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

Thus, compounds of formula (I) can be used in combination with one or more other herbicides to provide various herbicidal mixtures. Specific examples of such mixtures include (wherein “I” represents a compound of formula (I)):- 1 + acetochlor; I + acifluorfen (including acifluorfen-sodium); I + aclonifen; I + alachlor; I + alloxydim; I + ametryn; I + amicarbazone; I + amidosulfuron; I + aminocyclopyrachlor ; I + aminopyralid; I + amitrole; I + asulam; I + atrazine; I + bensulfuron (including bensulfuron-methyl); I + bentazone; I + bicyclopyrone; I + bilanafos; I + bifenox; I + bispyribac-sodium;

I + bixlozone; I + bromacil; I + bromoxynil; I + butachlor; I + butafenacil; I + cafenstrole; I + carfentrazone (including carfentrazone-ethyl); cloransulam (including cloransulam-methyl); I + chlorimuron (including chlorimuron-ethyl); I + chlorotoluron; I + cinosulfuron; I + chlorsulfuron; I + cinmethylin; I + clacyfos; I + clethodim; I + clodinafop (including clodinafop-propargyl); I + clomazone; I + clopyralid; I + cyclopyranil;

I + cyclopyrimorate; I + cyclosulfamuron; I + cyhalofop (including cyhalofop-butyl); I + 2,4-D (including the choline salt and 2-ethylhexyl ester thereof); I + 2,4-DB; I + daimuron; I + desmedipham; I + dicamba (including the aluminum, aminopropyl, bis-aminopropylmethyl, choline, dichloroprop, diglycolamine, dimethylamine, dimethylammonium, potassium and sodium salts thereof); I + diclofop-methyl; I + diclosulam; I + diflufenican; I + difenzoquat; I + diflufenican; I + diflufenzopyr; I + dimethachlor; I + dimethenamid-P; I + diquat dibromide; I + diuron; I + esprocarb; I + ethalfluralin; I + ethofumesate; I + fenoxaprop (including fenoxaprop-P-ethyl); I + fenoxasulfone; I + fenquinotrione; I + fentrazamide; I + flazasulfuron; I + florasulam; I + florpyrauxifen; I + fluazifop (including fluazifop-P-butyl); I + flucarbazone (including flucarbazone-sodium);; I + flufenacet; I + flumetralin; I + flumetsulam; I + flumioxazin; I + flupyrsulfuron (including flupyrsulfuron-methyl-sodium);; I + fluroxypyr (including fluroxypyr-meptyl);; I + fluthiacet-methyl; I + fomesafen; I + foramsulfuron; I + glufosinate (including the ammonium salt thereof);

I + glyphosate (including the diammonium, isopropylammonium and potassium salts thereof); I + halauxifen (including halauxifen-methyl); I + halosulfuron-methyl; I + haloxyfop (including haloxyfop- methyl); I + hexazinone; I + hydantocidin; I + imazamox; I + imazapic; I + imazapyr; I + imazaquin; I + imazethapyr; I + indaziflam; I + iodosulfuron (including iodosulfuron-methyl-sodium); I + iofensulfuron; I + iofensulfuron-sodium; I + ioxynil; I + ipfencarbazone; I + isoproturon; I + isoxaben; I + isoxaflutole; I + lactofen; I + lancotrione; I + linuron; I + MCPA; I + MCPB; I + mecoprop-P; I + mefenacet; I + mesosulfuron; I + mesosulfuron-methyl; I + mesotrione; I + metamitron; I + metazachlor; I + methiozolin; I + metobromuron; I + metolachlor; I + metosulam; I + metoxuron; I + metribuzin; I + metsulfuron; I + molinate; I + napropamide; I + nicosulfuron; I + norflurazon; I + orthosulfamuron; I + oxadiargyl; I + oxadiazon; I + oxasulfuron; I + oxyfluorfen; I + paraquat dichloride; I + pendimethalin; I + penoxsulam; I + phenmedipham; I + picloram; I + picolinafen; I + pinoxaden; I + pretilachlor; I + primisulfuron-methyl; I + prodiamine; I + prometryn; I + propachlor; I + propanil; I + propaquizafop; I + propham; I + propyrisulfuron, I + propyzamide; I + prosulfocarb; I + prosulfuron; I + pyraclonil; I + pyraflufen (including pyraflufen-ethyl): I + pyrasulfotole; I + pyrazolynate, I + pyrazosulfuron-ethyl; I + pyribenzoxim; I + pyridate; I + pyriftalid; I + pyrimisulfan, I + pyrithiobac-sodium; I + pyroxasulfone; I + pyroxsulam ; I + quinclorac; I + quinmerac; I + quizalofop (including quizalofop-P-ethyl and quizalofop-P-tefuryl),; I + rimsulfuron; I + saflufenacil; I + sethoxydim; I + simazine; I + S-metolachlor; I + sulcotrione; I + sulfentrazone; I + sulfosulfuron; I + tebuthiuron; I + tefuryltrione; I + tembotrione; I + terbuthylazine; I + terbutryn; I + thiencarbazone; I + thifensulfuron; I + tiafenacil; I + tolpyralate; I + topramezone; I + tralkoxydim; I + triafamone; I + triallate; I + triasulfuron; I + tribenuron (including tribenuron-methyl); I + triclopyr; I + trifloxysulfuron (including trifloxysulfuron-sodium); I + trifludimoxazin; I + trifluralin; I + triflusulfu ron; I + tritosulfuron; I + 4-hydroxy-1 -methoxy-5-methyl-3-[4-(trifluoromethyl)-2- pyridyl]imidazolidin-2-one; I + 4-hydroxy-1 ,5-dimethyl-3-[4-(trifluoromethyl)-2-pyridyl]imidazolidin-2- one; I + 5-ethoxy-4-hydroxy-1 -methyl-3-[4-(trifluoromethyl)-2-pyridyl]imidazolidin-2-one; I + 4-hydroxy-1 - methyl-3-[4-(trifluoromethyl)-2-pyridyl]imidazolidin-2-one; I + 4-hydroxy-1 ,5-dimethyl-3-[1 -methyl-5- (trifluoromethyl)pyrazol-3-yl]imidazolidin-2-one; I + (4R)1 -(5-tert-butylisoxazol-3-yl)-4-ethoxy-5-hydroxy-

3-methyl-imidazolidin-2-one; I + 3-[2-(3,4-dimethoxyphenyl)-6-methyl-3-oxo-pyridazine-4- carbonyl]bicyclo[3.2.1 ]octane-2,4-dione; I + 2-[2-(3,4-dimethoxyphenyl)-6-methyl-3-oxo-pyridazine-4- carbonyl]-5-methyl-cyclohexane-1 ,3-dione; I + 2-[2-(3,4-dimethoxyphenyl)-6-methyl-3-oxo-pyridazine-

4-carbonyl]cyclohexane-1 ,3-dione; I + 2-[2-(3,4-dimethoxyphenyl)-6-methyl-3-oxo-pyridazine-4- carbonyl]-5,5-dimethyl-cyclohexane-1 ,3-dione; I + 6-[2-(3,4-dimethoxyphenyl)-6-methyl-3-oxo- pyridazine-4-carbonyl]-2,2,4,4-tetramethyl-cyclohexane-1 ,3,5-trione; I + 2-[2-(3,4-dimethoxyphenyl)-6- methyl-3-oxo-pyridazine-4-carbonyl]-5-ethyl-cyclohexane-1 ,3-dione; I + 2-[2-(3,4-dimethoxyphenyl)-6- methyl-3-oxo-pyridazine-4-carbonyl]-4,4,6,6-tetramethyl-cycl ohexane-1 ,3-dione; I + 2-[6-cyclopropyl-2- (3, 4-dimethoxyphenyl)-3-oxo-pyridazine-4-carbonyl]-5-methyl-cyc lohexane-1 ,3-dione; I + 3-[6- cyclopropyl-2-(3,4-dimethoxyphenyl)-3-oxo-pyridazine-4-carbo nyl]bicyclo[3.2.1 ]octane-2,4-dione; I + 2- [6-cyclopropyl-2-(3,4-dimethoxyphenyl)-3-oxo-pyridazine-4-ca rbonyl]-5,5-dimethyl-cyclohexane-1 ,3- dione; I + 6-[6-cyclopropyl-2-(3,4-dimethoxyphenyl)-3-oxo-pyridazine-4- carbonyl]-2,2,4,4-tetramethyl- cyclohexane-1 ,3,5-trione; I + 2-[6-cyclopropyl-2-(3,4-dimethoxyphenyl)-3-oxo-pyridazine-4- carbonyl]cyclohexane-1 ,3-dione; I + 4-[2-(3,4-dimethoxyphenyl)-6-methyl-3-oxo-pyridazine-4-carbo nyl]- 2,2,6,6-tetramethyl-tetrahydropyran-3,5-dione and I + 4-[6-cyclopropyl-2-(3,4-dimethoxyphenyl)-3-oxo- pyridazine-4-carbonyl]-2,2,6,6-tetramethyl-tetrahydropyran-3 ,5-dione.

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

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

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

Compounds of formula (I) of the present invention may also be combined with herbicide safeners. Preferred combinations (wherein“I” represents a compound of formula (I)) include:- I + benoxacor, I + cloquintocet (including cloquintocet-mexyl); I + cyprosulfamide; I + dichlormid; I + fenchlorazole (including fenchlorazole-ethyl); I + fenclorim; I + fluxofenim; l+ furilazole I + isoxadifen (including isoxadifen-ethyl); I + mefenpyr (including mefenpyr-diethyl); I + metcamifen; I + N-(2- methoxybenzoyl)-4-[(methylaminocarbonyl)amino] benzenesulfonamide and I + oxabetrinil.

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

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

Preferably the mixing ratio of compound of formula (I) to safener is from 100:1 to 1 :10, especially from 20:1 to 1 :1 .

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

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

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

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

Useful plants in which the composition according to the invention can be used include crops such as cereals, for example barley and wheat, cotton, oilseed rape, sunflower, maize, rice, soybeans, sugar beet, sugar cane and turf. Crop plants can also include trees, such as fruit trees, palm trees, coconut trees or other nuts. Also included are vines such as grapes, fruit bushes, fruit plants and vegetables.

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

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

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

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

Compounds of formula (I) and compositions of the invention can typically be used to control a wide variety of monocotyledonous and dicotyledonous weed species. Examples of monocotyledonous species that can typically be controlled include Alopecurus myosuroides, Avena fatua, Brachiaria plantaginea, Bromus tectorum, Cyperus esculentus, Digitaria sanguinalis, Echinochloa crus-galli, Lolium perenne, Lolium multiflorum, Panicum miliaceum, Poa annua, Setaria viridis, Setaria faberi and Sorghum bicolor. Examples of dicotyledonous species that can be controlled include Abutilon theophrasti, Amaranthus retroflexus, Bidens pilosa, Chenopodium album, Euphorbia heterophylla, Galium aparine, Ipomoea hederacea, Kochia scoparia, Polygonum convolvulus, Sida spinosa, Sinapis arvensis, Solanum nigrum, Stellaria media, Veronica persica and Xanthium strumarium.

The compounds of formula (I) are also useful for pre-harvest desiccation in crops, for example, but not limited to, potatoes, soybean, sunflowers and cotton. Pre-harvest desiccation is used to desiccate crop foliage without significant damage to the crop itself to aid harvesting.

Compounds/compositions of the invention are particularly useful in non-selective burn-down applications, and as such may also be used to control volunteer or escape crop plants. Various aspects and embodiments of the present invention will now be illustrated in more detail by way of example. It will be appreciated that modification of detail may be made without departing from the scope of the invention.

EXAMPLES

The Examples which follow serve to illustrate, but do not limit, the invention.

FORMULATION EXAMPLES

Wettable powders a) b) c)

active ingredients 25 % 50 % 75 %

sodium lignosulfonate 5 % 5 %

sodium lauryl sulfate 3 % 5 %

sodium diisobutylnaphthalenesulfonate 6 % 10 %

phenol polyethylene glycol ether 2 %

(7-8 mol of ethylene oxide)

highly dispersed silicic acid 5 % 10 % 10 %

Kaolin 62 % 27 %

The combination is thoroughly mixed with the adjuvants and the mixture is thoroughly ground in a suitable mill, affording wettable powders that can be diluted with water to give suspensions of the desired concentration.

Emulsifiable concentrate

active ingredients 10 %

octylphenol polyethylene glycol ether 3 %

(4-5 mol of ethylene oxide)

calcium dodecylbenzenesulfonate 3 %

castor oil polyglycol ether (35 mol of ethylene oxide) 4 %

Cyclohexanone 30 %

xylene mixture 50 %

Emulsions of any required dilution, which can be used in plant protection, can be obtained from this concentrate by dilution with water.

Dusts a) b) c)

Active ingredients 5 % 6 % 4 %

Talcum 95 %

Kaolin - 94 %

mineral filler - - 96 %

Ready-for-use dusts are obtained by mixing the combination with the carrier and grinding the mixture in a suitable mill. Extruder granules

Active ingredients 15 %

sodium lignosulfonate 2 %

carboxymethylcellulose 1 %

Kaolin 82 %

The combination is mixed and ground with the adjuvants, and the mixture is moistened with water. The mixture is extruded and then dried in a stream of air.

Coated granules

Active ingredients 8 %

polyethylene glycol (mol. wt. 200) 3 %

Kaolin 89 %

The finely ground combination is uniformly applied, in a mixer, to the kaolin moistened with polyethylene glycol. Non-dusty coated granules are obtained in this manner.

Suspension concentrate

active ingredients 40 %

propylene glycol 10 %

nonylphenol polyethylene glycol ether (15 mol of ethylene oxide) 6 %

Sodium lignosulfonate 10 %

carboxymethylcellulose 1 %

silicone oil (in the form of a 75 % emulsion in water) 1 %

Water 32 %

The finely ground combination is intimately mixed with the adjuvants, giving a suspension concentrate from which suspensions of any desired dilution can be obtained by dilution with water. Slow Release Capsule Suspension

28 parts of the combination are mixed with 2 parts of an aromatic solvent and 7 parts of toluene diisocyanate/polymethylene-polyphenylisocyanate-mixture (8:1). This mixture is emulsified in a mixture of 1 .2 parts of polyvinylalcohol, 0.05 parts of a defoamer and 51 .6 parts of water until the desired particle size is achieved. To this emulsion a mixture of 2.8 parts 1 ,6-diaminohexane in 5.3 parts of water is added. The mixture is agitated until the polymerization reaction is completed.

The obtained capsule suspension is stabilized by adding 0.25 parts of a thickener and 3 parts of a dispersing agent. The capsule suspension formulation contains 28% of the active ingredients. The medium capsule diameter is 8-15 microns.

The resulting formulation is applied to seeds as an aqueous suspension in an apparatus suitable for that purpose. List of Abbreviations:

Boc = fe/f-butyloxycarbonyl

br = broad

CDCh = chloroform-d

CD3OD = methanol-d

°C = degrees Celsius

D2O = water-d

DCM = dichloromethane

d = doublet

dd = double doublet

dt = double triplet

DMSO = dimethylsulfoxide

EtOAc = ethyl acetate

h = hour(s)

HCI = hydrochloric acid

HPLC = high-performance liquid chromatography (description of the apparatus and the methods used for HPLC are given below)

m = multiplet

M = molar

min = minutes

MHz = mega hertz

mL = millilitre

mp = melting point

ppm = parts per million

q = quartet

quin = quintet

rt = room temperature

s = singlet

t = triplet

THF = tetrahydrofuran

LC/MS = Liquid Chromatography Mass Spectrometry

Preparative Reverse Phase HPLC Method:

Compounds purified by mass directed preparative HPLC using ES+/ES- on a Waters FractionLynx Autopurification system comprising a 2767 injector/collector with a 2545 gradient pump, two 515 isocratic pumps, SFO, 2998 photodiode array (Wavelength range (nm): 210 to 400), 2424 ELSD and QDa mass spectrometer. A Waters Atlantis T3 5micron 19x10mm guard column was used with a Waters Atlantis T3 OBD, 5micron 30x100mm prep column. Ionisation method: Electrospray positive and negative: Cone (V) 20.00, Source Temperature (°C) 120, Cone Gas Flow (L/Hr.) 50

Mass range (Da): positive 100 to 800, negative 115 to 800.

The preparative HPLC was conducted using an 11.4 minute run time (not using at column dilution, bypassed with the column selector), according to the following gradient table:

515 pump Oml/min Acetonitrile (ACD)

515 pump 1 ml/min 90% Methanol/10% Water (make up pump)

Solvent A: Water with 0.05% Trifluoroacetic Acid

Solvent B: Acetonitrile with 0.05% Trifluoroacetic Acid

Example 1 : Preparation of 3-[4-(1 -methyl-2 -oxo-4-pyridyl)pyridazin-1-ium-1-yl]propanoic acid 2,2,2-trifluoroacetate A5

Step 1 : Preparation of tributyl(pyridazin-4-yl)stannane

To a solution of lithium diisopropylamide (125 ml_, 1 M solution in tetrahydrofuran) at -78°C was added a solution of pyridazine (10g) and tri-n-butyltin chloride (44.6 g) in THF (100 ml_) drop wise under a nitrogen atmosphere. The reaction mixture was stirred at -78°C for 1 hour, then warmed to room temperature and quenched with saturated aqueous ammonium chloride (100 ml_) and extracted with ethyl acetate (3x150 ml_). The combined organic layers were dried over sodium sulfate, concentrated and purified by silica gel chromatography eluting with 30% ethyl acetate in hexanes to afford tributyl(pyridazin-4-yl)stannane as a pale brown liquid.

Ή NMR (400MHz, CDCb) 9.17 (t, 1 H) 9.02 (dd, 1 H) 7.54 (dd, 1 H) 1 .57-1 .49 (m, 6H) 1 .37-1 .29 (m, 6H) 1 .19-1 .13 (m, 6H) 0.92-0.86 (m, 9H)

Step 2: Preparation of 1 -methyl-4-pyridazin-4-yl-pyridin-2-one

A mixture of 4-bromo-1 -methyl-pyridin-2-one (100 mg) in 1 ,4-dioxane (2 ml_) was degassed with nitrogen for 20 minutes. To this was added tributyl(pyridazin-4-yl)stannane (0.235 g), tetrakis(triphenylphosphine)palladium(0) (0.062 g) and the reaction mixture was heated at 80°C for 16 hours under nitrogen atmosphere. The reaction mixture was concentrated and purified by silica gel chromatography eluting with 10% methanol in dichloromethane to afford 1 -methyl-4-pyridazin-4-yl- pyridin-2-one.

Ή NMR (400MHz, CD ₃ OD) 9.55 (s, 1 H), 9.31 (br d, 1 H), 8.03 (dd, 1 H), 7.85 (d, 1 H), 7.00 (s, 1 H), 6.79- 6.81 (m, 1 H), 3.63 (s, 3H)

Step 3: Preparation of 3-[4-(1 -methyl-2-oxo-4-pyridyl)pyridazin-1 -ium-1 -yl]propanoic acid 2,2,2- trifluoroacetate A5

A mixture of 1 -methyl-4-pyridazin-4-yl-pyridin-2-one (0.3 g), water (6 ml_) and 3-bromopropionic acid (0.253 g) was heated at 80°C for 16 hours. The reaction mixture was cooled, concentrated and purified by preparative reverse phase HPLC (trifluoroacetic acid was present in the eluent) to afford 3-[4-(1 - methyl-2-oxo-4-pyridyl)pyridazin-1 -ium-1 -yl]propanoic acid 2,2,2-trifluoroacetate

Ή NMR (400MHz, D2O) 9.89 (d, 1 H), 9.83 (s, 1 H), 8.88 (dd, 1 H), 7.97 (d, 1 H), 7.23 (d, 1 H), 7.00 (dd, 1 H), 5.20 (t, 2H), 3.70 (s, 3H), 3.34 (t, 2H) (CO2H proton missing)

Example 2: Preparation of 3-[4-(1-methyl-6-oxo-pyridazin-3-yl)pyridazin-1-ium-1-yl]pro panoic acid 2,2,2-trifluoroacetate A1

Step 1 : Preparation of 6-chloro-2-methyl-pyridazin-3-one

To a solution of 6-chloropyridazin-3-ol (2 g) in A/,A/-dimethylformamide (20 ml_) was added potassium carbonate (4.15 g) followed by iodomethane (1 .85 ml_) and the mixture was stirred at room temperature for 16 hours. The reaction mixture was partitioned between water and ethyl acetate. The organic layer was washed with water and brine, dried over sodium sulfate, concentrated then purified by silica gel chromatography eluting with 50-60% ethyl acetate in cyclohexane to give 6-chloro-2-methyl-pyridazin- 3-one.

Ή NMR (400MHz, CDCb) 7.18 (d, 1 H), 6.90 (d, 1 H), 3.72 (s, 3H)

Step 2: Preparation of 2-methyl-6-pyridazin-4-yl-pyridazin-3-one

A mixture of 6-chloro-2-methyl-pyridazin-3-one (1 .6 g) in 1 ,4-dioxane (16 ml_) was degassed with nitrogen for 20 minutes. To this was added tributyl(pyridazin-4-yl)stannane (4.9 g), tetrakis(triphenylphosphine)palladium(0) (1 .3 g) and the reaction mixture was heated at 1 10°C for 12 hours under nitrogen atmosphere. The reaction mixture was concentrated and purified by silica gel chromatography eluting with 10% methanol in dichloromethane to afford 2-methyl-6-pyridazin-4-yl- pyridazin-3-one.

Ή NMR (400 MHz, DMSO-de) 9.73 (dd, 1 H), 9.35 (dd, 1 H), 8.23 (d, 1 H), 8.12 (dd, 1 H), 7.15 (d, 1 H), 3.79 (s, 3H)

Step 3: Preparation of ethyl 3-[4-(1 -methyl-6-oxo-pyridazin-3-yl)pyridazin-1 -ium-1 -yl]propanoate bromide

A mixture of 2-methyl-6-pyridazin-4-yl-pyridazin-3-one (0.6 g), acetonitrile (6 ml_) and ethyl 3- bromopropanoate (0.613 ml_) was heated at 85°C for 12 hours. The reaction mixture was concentrated, washed with cyclohexane and fe/f-butyl methyl ether to afford crude ethyl 3-[4-(1 -methyl-6-oxo- pyridazin-3-yl)pyridazin-1 -ium-1 -yl]propanoate bromide which was used without further purification.

Step 4: Preparation of 3-[4-(1 -methyl-6-oxo-pyridazin-3-yl)pyridazin-1 -ium-1 -yl]propanoic acid 2,2,2- trifluoroacetate A1

A solution of crude ethyl 3-[4-(1 -methyl-6-oxo-pyridazin-3-yl)pyridazin-1 -ium-1 -yl]propanoate bromide (800 mg) in 2M hydrogen chloride in diethyl ether (8 ml_) was stirred at room temperature for 3 days. The reaction mixture was concentrated, washed with cyclohexane and fe/f-butyl methyl ether and purified by preparative reverse phase HPLC (trifluoroacetic acid was present in the eluent) to afford 3- [4-(1 -methyl-6-oxo-pyridazin-3-yl)pyridazin-1 -ium-1 -yl]propanoic acid 2,2,2-trifluoroacetate.

Ή NMR (400MHz, D ₂ 0) 9.99 (d, 1 H), 9.77 (d, 1 H), 8.88 (dd, 1 H), 8.26 (d, 1 H), 7.24 (d, 1 H), 5.10 (t, 2H), 3.94 (s, 3H), 3.27 (t, 2H) (CO2H proton missing)

Example 3: Preparation of 2-[4-(1 -methyl-2 -oxo-4-pyridyl)pyridazin-1-ium-1-yl]ethanesulfonate A4

A mixture of 1 -methyl-4-pyridazin-4-yl-pyridin-2-one (0.39 g) and sodium 2-bromoethanesulfonic acid (0.442 g) in water (7.8 ml_) was heated at 80°C for 48 hours. The reaction mixture was cooled, concentrated and purified by preparative reverse phase HPLC to give 2-[4-(1 -methyl-2-oxo-4- pyridyl) pyridazin-1 -ium-1 -yljethanesulfonate.

Ή NMR (400MHz, D2O) 9.85-9.90 (m, 2H), 8.89 (dd, 1 H), 7.97 (d, 1 H), 7.25 (d, 1 H), 7.02 (dd, 1 H), 5.33 (t, 2H), 3.78 (t, 2H), 3.71 (s, 3H)

Example 4: Preparation of 3-[4-[1-(cyanomethyl)-2-oxo-4-pyridyl]pyridazin-1 -ium-1 -yl]propanoic acid 2,2,2-trifluoroacetate A19

Step 1 : Preparation of 2-(4-bromo-2-oxo-1 -pyridyl)acetonitrile A mixture of 4-bromo-1 H-pyridin-2-one (1 g), potassium carbonate (1 .204 g) and bromoacetonitrile (0.62 ml_) in tetrahydrofuran (10 ml_) was heated at 50°C for 12 hours. The reaction mixture was filtered and the filtrate concentrated. The resulting residue was purified by silica gel chromatography eluting with a mixture of methanol in dichloromethane to give 2-(4-bromo-2-oxo-1 -pyridyl)acetonitrile as a white solid.

Ή NMR (400MHz, CDCb) 7.31 - 7.22 (m, 1 H), 6.94 - 6.87 (m, 1 H), 6.47 (d, 1 H), 4.82 (s, 2H)

Step 2: Preparation of 2-(2-oxo-4-pyridazin-4-yl-1 -pyridyl)acetonitrile

To a microwave vial was added tributyl(pyridazin-4-yl)stannane (1 .9 g), 2-(4-bromo-2-oxo-1 - pyridyl)acetonitrile (1 g) and 1 ,4-dioxane (10 ml_) and the mixture was purged with nitrogen.

Tetrakis(triphenylphosphine)palladium(0) (0.54 g) was added and the mixture was heated at 120°C for 1 hour under microwave irradiation. The reaction mixture was concentrated and the residue was washed with fe/f-butyl methyl ether and purified by silica gel chromatography eluting with a mixture of methanol in dichloromethane to give 2-(2-oxo-4-pyridazin-4-yl-1 -pyridyl)acetonitrile as a light brown solid.

Ή NMR (400 MHz, DMSO-de) 9.65 (m, 1 H), 9.37 (d, 1 H), 8.06-8.08 (m, 1 H), 7.97 (d, 1 H), 7.14 (d,

1 H), 6.86-6.89 (m, 1 H), 5.06 (s, 2H)

Step 3: Preparation of 3-[4-[1 -(cyanomethyl)-2-oxo-4-pyridyl]pyridazin-1 -ium-1 -yl]propanoic acid 2,2,2- trifluoroacetate A19

A mixture of 2-(2-oxo-4-pyridazin-4-yl-1 -pyridyl)acetonitrile (0.74 g) and 3-bromopropanoic acid (0.587 g) in acetonitrile (21 ml_) was heated at 80°C for 72 hours. The reaction mixture was concentrated and the residue was washed with fe/f-butyl methyl ether and purified by preparative reverse phase HPLC (trifluoroacetic acid was present in the eluent) to give 3-[4-[1 -(cyanomethyl)-2-oxo-4-pyridyl]pyridazin- 1 -ium-1 -yl]propanoic acid 2,2,2-trifluoroacetate as an off-white solid.

Ή NMR (400MHz, D ₂ 0) 9.89 (d, 1 H), 9.82 (d, 1 H), 8.87 (dd, 1 H), 7.97 (d, 1 H), 7.28 (d, 1 H), 7.01 (dd,

1 H), 5.18 (t, 2H), 5.12 (s, 2H), 3.30 (t, 2H) (CO2H proton missing)) Example 5: Preparation of 4-bromo-1-ethyl-pyridin-2-one

A mixture of 4-bromo-1 H-pyridin-2-one (0.1 g) in A/,A/-dimethylformamide (1 ml_), under nitrogen atmosphere, was cooled to ~0°C and sodium hydride (60% dispersion in mineral oil, 0.042 g) was added. The reaction mass was stirred for 45 minutes at ~0°C and then iodoethane (0.071 ml_) was added. The reaction was allowed to warm to room temperature and stirred overnight. The reaction mass was quenched with sat. aqueous ammonium chloride and extracted with ethyl acetate (3x20 ml_). The combined organic phases were dried over sodium sulfate, concentrated and purified by silica gel chromatography eluting with a mixture of ethyl acetate and cyclohexane to give 4-bromo-1 - ethyl-pyridin-2-one as a colourless oil.

Ή NMR (400MHz, CDC ) 7.13 (d, 1 H), 6.81 (d, 1 H), 6.33 (dd, 1 H), 3.94 (q, 2H), 1 .34 (t, 3H)

Example 6: Preparation of 3-[4-[1-(2-amino-2-oxo-ethyl)-2-oxo-4-pyridyl]pyridazin-1-iu m-1- yl]propanoic acid 2,2,2-trifluoroacetate A9

A mixture of 2-(2-oxo-4-pyridazin-4-yl-1 -pyridyl)acetonitrile (0.14 g), water (2.8 ml_) and 3- bromopropionic acid (0.101 g) was heated at 100°C for 12 hours. The reaction mixture was cooled, concentrated and purified by preparative reverse phase HPLC (trifluoroacetic acid was present in the eluent) to give 3-[4-[1 -(2-amino-2-oxo-ethyl)-2-oxo-4-pyridyl]pyridazin-1 -ium-1 -yl]propanoic acid 2,2,2- trifluoroacetate.

Ή NMR (400MHz, D ₂ 0) 9.82 (d, 1 H), 9.76 (d, 1 H), 8.83 - 8.80 (m, 1 H), 7.83 (d, 1 H), 7.17 (d, 1 H), 6.96 - 6.92 (m, 1 H), 5.12 (t, 2H), 4.80 (s, 2H), 3.26 (t, 2H) (NH and C0 ₂ H protons missing) Example 7: Preparation of 1-(2-methylsulfonylethyl)-4-pyridazin-4-yl-pyridin-2-one

Step 1 : Preparation of 4-pyridazin-4-yl-1 H-pyridin-2-one

A mixture of tributyl(pyridazin-4-yl)stannane (11.67 g) and 4-bromo-1 H-pyridin-2-one (5 g) in 1 ,4- dioxane (50 mL) was purged with nitrogen. Tetrakis(triphenylphosphine)palladium(0) (1.99 g) was added and the mixture was heated at 100°C for 8 hours. The reaction mixture was concentrated and the residue was washed with fe/f-butyl methyl ether and purified by silica gel chromatography eluting with a mixture of methanol in dichloromethane to give 4-pyridazin-4-yl-1 H-pyridin-2-one as a brown solid.

Ή NMR (400 MHz, DMSO-de) 1 1.88 (brs, 1 H), 9.61 (d, 1 H), 9.33-9.35 (m, 1 H), 8.02-8.04 (m, 1 H), 7.57 (d, 1 H), 6.91-6.92 (m, 1 H), 6.65-6.68 (m, 1 H)

Step 2: Preparation of 1-(2-methylsulfonylethyl)-4-pyridazin-4-yl-pyridin-2-one

A mixture of 4-pyridazin-4-yl-1 H-pyridin-2-one (0.3 g) in dimethyl sulfoxide (5 mL), under nitrogen atmosphere, was cooled to ~0°C and sodium hydride (60% dispersion in mineral oil, 0.083 g) was added. The reaction mass was stirred for 10 minutes at ~0°C and then 1-bromo-2- (methylsulfonyl)ethane (0.389 g) was added. The reaction was allowed to warm to room temperature and stirred for an hour. The reaction mass was quenched with water and the resulting precipitate was stirred for 10 minutes then filtered off. The solid was washed with fe/f-butyl methyl ether and dried to give 1-(2-methylsulfonylethyl)-4-pyridazin-4-yl-pyridin-2-one as a light yellow solid.

Ή NMR (400 MHz, DMSO-de) 9.64(s, 1 H), 9.35 (d, 1 H), 8.06-8.08 (m, 1 H), 7.92 (d, 1 H), 7.05 (d, 1 H), 6.80-6.82 (m, 1 H), 4.35 (t, 2H), 3.60 (t, 2H), 3.08 (s, 3H) Example 8: Preparation of 1-cyclopropyl-4-pyridazin-4-yl-pyridin-2-one

A mixture of 4-pyridazin-4-yl-1 H-pyridin-2-one (0.5 g) in 1 ,2-dichloroethane (14.4 ml_) was purged with nitrogen. To this was added cyclopropylboronic acid (0.57 g), 2-(2-pyridyl) pyridine (0.528 g), copper(ll) acetate (0.591 g) and sodium carbonate (0.696 g). The mixture was heated at 80°C for 12 hours. The reaction mixture was concentrated and the residue was washed with fe/f-butyl methyl ether and purified by silica gel chromatography eluting with a mixture of methanol in dichloromethane to give 1 -cyclopropyl-4-pyridazin-4-yl-pyridin-2-one as an off-white solid.

Ή NMR (400MHz, CDCb) 9.37 (s, 1 H), 9.29 (d, 1 H), 7.61 -7.63 (m, 1 H), 7.47 (d, 1 H), 6.85 (d, 1 H), 6.36-6.41 (m, 1 H), 3.35-3.41 (m, 1 H), 1 .08-1 .28 (m, 2H), 0.84-0.93 ppm (m, 2H)

Example 9: Preparation of 3-[4-[1-(2-aminoethyl)-2-oxo-4-pyridyl]pyridazin-1-ium-1-yl] propanoic acid 2,2,2-trifluoroacetate A24

Step 1 : Preparation of tert-butyl N-[2-(4-bromo-2-oxo-1 -pyridyl)ethyl]carbamate

A mixture of 4-bromo-1 H-pyridin-2-one (1 g), potassium carbonate (1 .204 g) and tert-butyl N-(2- bromoethyl)carbamate (1 .932 g) in tetrahydrofuran (10 ml_) was heated at 50°C for 12 hours. The reaction mixture was quenched with water and extracted with ethyl acetate (3x20 ml_). The combined organic layers were dried over sodium sulfate, concentrated and purified by silica gel chromatography eluting with a mixture of ethyl acetate in cyclohexane to give tert-butyl N-[2-(4-bromo-2-oxo-1 - pyridyl)ethyl]carbamate as a white solid.

Ή NMR (400MHz, CDCb) 7.12 (br d, 1 H), 6.81 (d, 1 H), 6.33 (dd, 1 H), 5.00 (br s, 1 H), 4.05 (br t, 2H), 3.44 (q, 2H), 1 .42 (s, 9H) Step 2: Preparation of tert-butyl N-[2-(2-oxo-4-pyridazin-4-yl-1 -pyridyl)ethyl]carbamate

To a microwave vial was added tributyl(pyridazin-4-yl)stannane (2.24 g), tert-butyl N-[2-(4-bromo-2- oxo-1 -pyridyl)ethyl]carbamate (1 .75 g) and 1 ,4-dioxane (10.5 ml_) and the mixture was purged with nitrogen. Tetrakis(triphenylphosphine)palladium(0) (0.638 g) was added and the mixture was heated at 120°C for 1 hour under microwave irradiation. The reaction mixture was concentrated and the residue was washed with fe/f-butyl methyl ether and purified by silica gel chromatography eluting with a mixture of methanol in dichloromethane to give tert-butyl N-[2-(2-oxo-4-pyridazin-4-yl-1 - pyridyl)ethyl]carbamate as an off-white solid.

Step 3: Preparation of 3-[4-[1 -(2-aminoethyl)-2-oxo-4-pyridyl]pyridazin-1 -ium-1 -yl]propanoic acid 2,2,2- trifluoroacetate A24

A mixture of tert-butyl N-[2-(2-oxo-4-pyridazin-4-yl-1 -pyridyl)ethyl]carbamate (0.54 g) and 3- bromopropanoic acid (0.287 g) in acetonitrile (10.24 ml_) was heated at 80°C for 96 hours. The reaction mixture was concentrated and the residue was washed with fe/f-butyl methyl ether. The residue was dissolved in 4M hydrogen chloride in 1 ,4-dioxane (10 ml_) and stirred until completion.

The mixture was concentrated and purified by preparative reverse phase HPLC (trifluoroacetic acid was present in the eluent) to give 3-[4-[1 -(2-aminoethyl)-2-oxo-4-pyridyl]pyridazin-1 -ium-1 -yl]propanoic acid 2,2,2-trifluoroacetate.

Ή NMR (400MHz, D ₂ 0) 9.88 (d, 1 H), 9.81 (d, 1 H), 8.86 (dd, 1 H), 7.92 (d, 1 H), 7.23 (d, 1 H), 6.99 (dd,

1 H), 5.18 (t, 2H), 4.43 (t, 2H), 3.48 (t, 2H), 3.31 (t, 2H) (NH and CO2H protons missing)

Example 10: Preparation of 1-(2-hydroxyethyl)-4-pyridazin-4-yl-pyridin-2-one

Step 1 : Preparation of 1 -[2-[tert-butyl(dimethyl)silyl]oxyethyl]-4-pyridazin-4-yl-py ridin-2-one

A mixture of 4-pyridazin-4-yl-1 H-pyridin-2-one (1 g) in A/,A/-dimethylformamide (16 mL), under nitrogen atmosphere, was cooled to ~0°C and sodium hydride (60% dispersion in mineral oil, 0.35 g) was added. The reaction mass was stirred for 10 minutes at ~0°C and then 2-bromoethoxy-tert-butyl- dimethyl-silane (1 .7 g) was added. The reaction was allowed to warm to room temperature and stirred for 16 hours. The reaction mass was quenched with water and extracted with ethyl acetate (3x20 mL). The combined organic phases were dried over sodium sulfate and concentrated to give crude 1 -[2- [tert-butyl(dimethyl)silyl]oxyethyl]-4-pyridazin-4-yl-pyridi n-2-one, which was used without further purification.

Step 2: Preparation of 1 -(2-hydroxyethyl)-4-pyridazin-4-yl-pyridin-2-one

To a mixture of 1 -[2-[tert-butyl(dimethyl)silyl]oxyethyl]-4-pyridazin-4-yl-py ridin-2-one (0.1 1 g) in acetonitrile (3.4 mL) was added 1 M aqueous hydrochloric acid (3.32 mL) and the reaction mixture was stirred at room temperature for 16 hours. The reaction mixture was concentrated and the residue was washed with fe/f-butyl methyl ether and dried to give 1 -(2-hydroxyethyl)-4-pyridazin-4-yl-pyridin-2-one as a yellow solid.

Ή NMR (400 MHz, DMSO-de) 9.67 (dd, 1 H) 9.39 (dd, 1 H) 8.13 (dd, 1 H) 7.81 (d, 1 H) 7.02 (d, 1 H) 6.74 (dd, 1 H) 4.00 (t, 2H) 3.65 (t, 2H) (OH proton missing)

Example 11 : Preparation of 1-methyl-3-pyridazin-4-yl-pyridazin-4-one

Step 1 : Preparation of 3-bromo-4-methoxy-pyridazine

A solution of 4-methoxypyridazin-3-amine (0.2 g) in acetonitrile (6 mL), under nitrogen atmosphere, was cooled to ~0°C. To this was added cupric bromide (0.393 g) followed by tert-butyl nitrite (0.528 ml_). The reaction mixture was stirred for 1 hour at ~0°C and then 16 hours at room temperature. The reaction was quenched with EDTA solution and extracted with ethyl acetate (3x50 ml_). The combined organic layers were concentrated to give crude 3-bromo-4-methoxy-pyridazine, which was used without further purification.

Step 2: Preparation of 3-bromo-1-methyl-pyridazin-4-one

A mixture of 3-bromo-4-methoxy-pyridazine (0.2 g), iodomethane (0.132 ml_) and acetone (4 ml_) was stirred at room temperature for 16 hours. The mixture was concentrated to give 3-bromo-1-methyl- pyridazin-4-one.

Ή NMR (400MHz, CDCb) 7.75-7.77 (m, 1 H), 6.53-6.56 (m, 1 H), 3.96 (s, 3H)

Step 3: Preparation of 1-methyl-3-pyridazin-4-yl-pyridazin-4-one

To a microwave vial was added tributyl(pyridazin-4-yl)stannane (0.733 g), 3-bromo-1-methyl-pyridazin- 4-one (0.25 g) and 1 ,4-dioxane (5 ml_) and the mixture was purged with nitrogen.

Tetrakis(triphenylphosphine)palladium(0) (0.23 g) was added and the mixture was heated at 140°C for 1.5 hours under microwave irradiation. The reaction mixture was concentrated and the residue was washed with fe/f-butyl methyl ether and purified by silica gel chromatography eluting with a mixture of methanol in dichloromethane to give 1-methyl-3-pyridazin-4-yl-pyridazin-4-one as a brown solid.

Ή NMR (400MHz, CDCb) 9.87 (s, 1 H), 9.26 (dd, 1 H), 8.64 (dd, 1 H), 7.82 (d, 1 H), 6.66 (d, 1 H), 4.06 (s, 3H)

Example 12: Preparation of 1-methyl-5-pyridazin-4-yl-pyridazin-4-one

Step 1 : Preparation of 1-methylpyridazin-4-one To a mixture of pyridazin-4-ol (0.5 g) and potassium carbonate (0.741 g) in acetone (15 ml_), under nitrogen atmosphere, was added dimethyl sulfate (0.591 ml_) and the reaction mass was heated at 40°C for 12 hours. The reaction mixture was concentrated and purified by silica gel chromatography eluting with a mixture of ethyl acetate in methanol to give 1 -methylpyridazin-4-one.

Ή NMR (400 MHz, DMSO-de) 8.20 (d, 1 H) 7.73 (d, 1 H) 6.32 (dd, 1 H) 3.82 (s, 3H)

Step 2: Preparation of 5-bromo-1 -methyl-pyridazin-4-one

To a mixture of 1 -methylpyridazin-4-one (1 .5 g) and potassium acetate (1 .3 g) in glacial acetic acid (15 ml_) was added a solution of bromine (0.72 ml_) in glacial acetic acid (15 ml_) over 10 minutes. The mixture was heated at reflux for 45 minutes, cooled to room temperature, poured into ice water (200 ml_) and extracted with ethyl acetate (3x200 ml_). The combined organic layers were dried over sodium sulfate and concentrated to give 5-bromo-1 -methyl-pyridazin-4-one.

Ή NMR (400 MHz, DMSO-de) 8.89 (s, 1 H) 7.84 (s, 1 H) 3.85 (s, 3H)

Step 3: Preparation of 1 -methyl-5-pyridazin-4-yl-pyridazin-4-one

To a microwave vial was added tributyl(pyridazin-4-yl)stannane (1 .504 g), 5-bromo-1 -methyl-pyridazin- 4-one (0.7 g) and 1 ,4-dioxane (14 ml_) and the mixture was purged with nitrogen.

Tetrakis(triphenylphosphine)palladium(0) (0.429 g) was added and the mixture was heated at 140°C for 1 hour under microwave irradiation. The reaction mixture was concentrated and the residue was washed with fe/f-butyl methyl ether and purified by silica gel chromatography eluting with a mixture of methanol in dichloromethane to give 1 -methyl-5-pyridazin-4-yl-pyridazin-4-one.

Ή NMR (400 MHz, CD ₃ OD) 9.68 - 9.73 (m, 1 H) 9.22 (d, 1 H) 8.92 (s, 1 H) 8.29-8.31 (m, 2H) 8.02 (s,

1 H) 4.06 (s, 3H)

Additional compounds in Table A were prepared by analogous procedures, from appropriate starting materials. Table A Physical data for compounds of the invention

BIOLOGICAL EXAMPLES

Post-emergence efficacy

Method A

Seeds of a variety of test species were sown in standard soil in pots. After cultivation for 14 days

(post-emergence) under controlled conditions in a glasshouse (at 24/16°C, day/night; 14 hours light; 65 % humidity), the plants were sprayed with an aqueous spray solution derived from the dissolution of the technical active ingredient formula (I) in a small amount of acetone and a special solvent and emulsifier mixture referred to as IF50 (1 1 .12% Emulsogen EL360 TM + 44.44% N-methylpyrrolidone + 44.44% Dowanol DPM glycol ether), to create a 50g/l solution which was then diluted to required concentration using 0.25% or 1 % Empicol ESC70 (Sodium lauryl ether sulphate) + 1 % ammonium sulphate as diluent.

The test plants were then grown in a glasshouse under controlled conditions (at 24/16°C, day/night; 14 hours light; 65 % humidity) and watered twice daily. After 13 days the test was evaluated (100 = total damage to plant; 0 = no damage to plant).

The results are shown in Table B (below). A value of n/a indicates that this combination of weed and test compound was not tested/assessed.

Test plants:

Ipomoea hederacea (IPOHE), Euphorbia heterophylla (EPHHL), Chenopodium album (CHEAL), Amaranthus palmeri (AMAPA), Lolium perenne (LOLPE), Digitaria sanguinalis (DIGSA), Eleusine indica (ELEIN), Echinochloa crus-galli (ECHCG), Setaria faberi (SETFA)

Table B Control of weed species by compounds of formula (I) after post-emergence application