WO1992008696A1

WO1992008696A1 - Herbicides

Info

Publication number: WO1992008696A1
Application number: PCT/AU1991/000529
Authority: WO
Inventors: Kevin Norman Winzenberg; Andris Juris Liepa
Original assignee: Dunlena Pty. Limited
Priority date: 1990-11-20
Filing date: 1991-11-20
Publication date: 1992-05-29

Abstract

Compounds of formula (1) or isomeric and/or tautomeric forms thereof wherein R1 is H, or one of a number of specified groups, or M; R2 is C1-C4 alkyl, R3 is C1-C4 alkyl, or one of a number of specified groups; R?4 and R5¿ are independently H, or C¿1?-C4 alkyl, C2-C4 alkenyl; R?6¿ is hydrogen, or one of a number of specified groups; X is -SO¿2?R?7, -CONR7R8, -COR7, -CO¿2R7, -SO2NR?7R8, -CSNR7R8; R7 and R8¿ are independently hydrogen, C¿1?-C6 alkyl, C3-C6 cycloalkyl; or R?7 and R8¿ together with the nitrogen to which they are attached form a 5- to 7-membered heterocyclic ring; n is 0, 1, 2, 3, 4 or 5; provided that when n = 0, then X is not COR7, CO2R7 or CONR7R8; and M is Li?+, Na+, K+, NH¿4+, or N(R11)4+ where R11 is C1-C4 alkyl. Processes for preparing the compounds, herbicidal and plant growth regulating compositions containing them and methods for regulating the growth of a plant and selectively inhibiting, damaging or killing weed grasses in a crop involving them.

Description

"HERBICIDES"

The present invention relates to organic compounds having herbicidal properties and plant growth regulating properties; to herbicidal compositions and processes utilizing such compounds and to plant growth regulating compositions and processes utilizing such compositions.

The use of certain cyclohexane-1,3-dione derivatives as grass herbicides is known in the art. Thus, for example, the compendium "The Pesticide Manual, 8th Edition" (C.R. Worthing Editor, The British Crop Protection Council, Thornton Heath, UK) describes the cyclohexane-1,3-dione derivatives known commercially as Alloxydim sodium methyl (E)-(RS)-3-[1- (alloxyimino)butyl]-4-hydroxy-6,6-dimethyl-2-oxocyclohex-3-ene carboxylate, Cycloxydim (RS)-2-[1-(ethoxyimino)butyl]-3-hydroxy-5-thian-3-ylcyclohex-2-enone and Sethoxydim (RS)-(ZE)-2-(1-ethoxyiminobutyl)-5-[2-(ethylthio)propyl]-3-hydroxycyclohex-2-enone.

United States patent 4,872,902-A in the name of Ciba-Geigy

Corporation discloses herbicidal compounds of the formula:

wherein

R is H, C₁-C₆ alkyl;

R¹ is R², OR³, NR³R⁴;

R² is optionally substituted C₁-C₆ alkyl, C₃-C₆ cycloalkyl; R³ is C₁-C₆ alkyl, C₃-C₆ cycloalkyl, optionally substituted phenyl, optionally substituted benzyl;

R⁴ is H, C₁-C₆ alkyl, C₁-C₆ cycloalkyl, C₁-C₆ alkoxy or NR³R⁴ is a pyrrolidine, piperidine or morpholine ring;

R⁶ is C₁-C₆ cycloalkyl;

R⁷ is H, optionally halogenated C₁-C₆ alkyl, C₃-C₆ alkenyl, halogenoalkenyl or alkynyl.

The present invention seeks to provide novel compounds which have herbicidal activity, as well as agriculturally useful compositions of these compounds and methods of using these compounds as pre-emergent and/or post-emergent herbicides and plant growth regulators.

The invention provides compounds of the formula (1) or isomeric and/or tautomeric forms thereof:

wherein

R¹ is H, C₁-C₄ alkyl, C₂-C₄ alkenyl, C₂-C₄ alkynyl or M;

R² is C₁-C₄ alkyl;

R³ is C₁-C₄ alkyl, C₂-C₄ alkenyl, C₂-C₄ alkenyl with 1-3 halogen substituents, C₂-C₄ alkynyl, phenyl optionally substituted with 0-3 substituents selected from the group consisting of halogen, C₁-C₄ alkyl, C₁-C₄ alkoxy, C₁-C₄ alkythio, C₁-C₄ haloalkyl, C₁-C₄ haloalkoxy, nitro, cyano, phenyl (optionally substituted with 0-3 substituents selected from the group consisting of halogen, C₁-C₄ alkyl, C₁-C₄ alkoxy, C₁-C₄ haloalkyl, C₁-C₄ haloalkoxy, nitro, and cyano) and

phenoxy (optionally substituted with 0-3 substituents selected from the group consisting of halogen, C₁-C₄ alkyl, C₁-C₄ alkoxy, C₁-C₄ haloalkyl, C₁-C₄ haloalkoxy, nitro, and cyano);

R⁴ and R⁵ are independently H, or C₁-C₄ alkyl, C₂-C₄ alkenyl;

R⁶ is hydrogen, C₁-C₆ alkyl, C₂-C₆ alkoxyalkyl, C₃-C₆ cycloalkyl, C₁-C₆ alkyl substituted with an optionally substituted phenyl group wherein the substituent on the phenyl group is selected from the group consisting of halogen, C₁-C₄ alkyl, C₁-C₄ alkoxy, C₁-C₄ alkylthio, C₁-C₄ haloalkyl, and C₁-C₄ haloalkoxy, phenyl, phenyl optionally substituted with 1-3 substituents selected from the group consisting of halogen, C₁-C₄ alkyl, C₁-C₄ alkoxy, C₁-C₄ alkylthio, C₁-C₄ haloalkyl, and C₁-C₄ haloalkoxy;

X is -SO₂R⁷, -CONR⁷R⁸, -COR⁷, -CO₂R⁷, -SO₂NR⁷R⁸, -CSNR⁷R⁸; R⁷ and R⁸ are independently hydrogen, C₁-C₆ alkyl, C₃-C₆ cycloalkyl;

or

R⁷ and R⁸ together with the nitrogen to which they are attached form a fully saturated- or an unsaturated 5- to 7-membered heterocyclic ring containing 1-3 heteroatoms selected from the group consisting of 1-3 nitrogen, 0-2 oxygen and 0-2 sulfur atoms; n is 0, 1, 2, 3, 4 or 5; provided that when n = 0, then X is not COR⁷, CO₂R⁷ or CONR⁷R⁸; and

M is Li⁺, Na⁺, K⁺, NH₄ ⁺, or N(R¹¹)₄ ⁺ where R¹¹ is C₁-C₄ alkyl. In the above definitions, the term "alkyl", used either alone or in compound words such as "alkylthio" or "haloalkyl", denotes straight chain or branched alkyl, e.g. methyl, ethyl, n-propyl, isopropyl or the different butyl, pentyl or hexyl isomers.

Alkoxy denotes methoxy, ethoxy, n-propoxy, isopropyloxy, and the different butyloxy isomers.

Alkenyl denotes straight chain or branched alkenes, e.g. vinyl, 1-propenyl, 2-propenyl, 3-propenyl, etc.

Alkynyl denotes straight chain or branched alkynes, e.g., ethynyl, 1-propynyl, 2-propynyl, and the different butynyl isomers. Alkylsulfonyl denotes methylsulfonyl, ethylsulfonyl, propylsulfonyl, and the different butylsulfonyl isomers.

Alkylthio, alkylsulfinyl, alkylamino, etc. are defined in an analogous manner.

Cycloalkyl denotes cyclopropyl, cyclobutyl, cyclopentyl, cyclohexyl, and cycloheptyl.

The term "halogen", either alone or in compound words such as "haloalkyl", denotes fluorine, chlorine, bromine or iodine. In halogen-substituted groups, such as "haloalkyl" or "haloalkoxy" the alkyl moieties may be partially halogenated or fully substituted with halogen atoms which may be the same or different. Examples of haloalkyl include CH₂CH₂F, CF₂CF₃ and CH₂CHFCl.

Alkylcarbonyl denotes acetyl, propionyl, and the different butyryl isomers. Alkoxycarbonyl denotes methoxycarbonyl, ethoxycarbonyl,

propoxycarbonyl, isopropoxycarbonyl, and the different butoxycarbonyl isomers.

The total number of carbon atoms in a substituent group is indicated by the Ci-Cj prefix where i and j are numbers from 1 to 10. For example, C₂-C₃ alkylthioalkyl would designate -CH₂SCH₃, -CH₂SC₂H₅, -CH₂CH₂SCH₃ or -CH(CH₃)SCH₃, and C₂-C₅ alkoxyalkyl represents -CH₂OCH₃ through to -(CH₂)₄OCH₃ or -CH₂O(CH₂)₃CH₃ and the various structural isomers embraced therein.

Alkylene denotes methylene (-CH₂-), propylene and butylene;

alkenylene denotes -CH = CH₂CH₂-, -CH = CHCH₂CH₂-, and

"CH₂-CH = CHCH₂- Specific examples of compounds of invention of Formula (1) include those compounds detailed in Tables 1-9 below, ("mp" indicates the melting point in degrees Celsius.)

It should be recognized that when R¹ is hydrogen the compounds (1) of the invention may undergo tautomerisation. All tautomeric forms are included in the scope of this invention. The compounds of the invention may be prepared by reduction of amines of formula (2) wherein R⁴, R⁵, R⁶ and n are as defined above and R⁹ is hydrogen or C₁-C₆ alkyl. Compounds of formula (2) are readily obtainable by customary methods described in the literature.

A convenient reduction procedure, as set out in the reaction scheme below, involves the reaction of compounds of type (2) wherein R⁹ = C₁-C₆ alkyl with alkali metals in liquid ammonia in the presence of t-butanol

(Scheme) (Olson, G.L., Cheung, H.-C, Morgan, K.D., Blount, J.F., Todaro, L., and Berger, L., J. Med. Chem, 1981, 24, 1026; Mann, A., Humblet, C.,

Chambon, J.P., Schlichter, R., Desarmenien, M., Feltz, P., and Wermuth, C.-G., J. Med. Chem., 1985, 28, 1440).

The 3,5-dialkoxycyclohexa-2,5-diene derivatives (3) thus obtained may be reacted with sulfonyl chlorides R⁷SO₂Cl, acyl chlorides R⁷COCl or anhydrides (R⁷CO)₂0, chloroformate esters R⁷OCOCl, carbamoyl chlorides R⁷R⁸NCOCl or isocyanates R⁷NCO, dialkylsulfamoyl chlorides R⁷R⁸NSO₂Cl or with dialkylthiocarbamoyl chlorides R⁷R⁸CSCl to afford, after acid hydrolysis, the sulfonamides (5, X = SO₂R⁷),the amides (5, X=COR⁷), the carbamates (5, X=CO₂R⁷) the ureas (5, X = CONR⁷R⁸), the sulfamides (5, X=SO₂NR⁷R⁸) or the thioureas (5, X=CSNR⁷R⁸) respectively, wherein R⁷ and R⁸ are as defined aboved. The cyclohexanediones (5) thus obtained may be acylated on oxygen and the enol esters isomerized (Fries rearrangement) to give the novel C-substituted products (6). The C-acylated derivatives (6) may be reacted with O-substituted hydroxylamines which may in turn be generated in situ from appropriate precursors, to afford derivatives of the general Formula (1) wherein R¹ is hydrogen.

Compounds of the invention of Formula (1) wherein R¹ is not hydrogen may be prepared by standard synthetic procedures. For example, compounds of the invention of Formula (1) wherein R¹ is an organic or inorganic cation may be prepared from compounds of the invention of Formula (1) wherein R¹ is hydrogen by reacting these latter compounds with an appropriate inorganic or organic base.

Esterification of the vinylogous acid in compounds of the invention of Formula (1) wherein R¹ is hydrogen provides further herbicidal and growth regulating derivatives.

The general procedure for preparation of Compounds of the Invention is described in detail in the following section. General Procedures for Preparation of Compounds of the Invention

Synthesis of Cyclohexane-1,3-diones (5) wherein X = SO₂R⁷ To a stirred solution of an appropriate amine (2) (100 mmol) and t-butanol (1 mol) in tetrahydrofuran (200 ml) and ammonia (ca 500 ml) at - 78 °C under argon was added portionwise lithium metal (1 mol). The mixture was stirred for 6 h at -33 °C and then carefully quenched by the addition of ammonium chloride (1 mol). The ammonia was allowed to evaporate and to the residue was added water (200 ml) followed by chloroform (200 ml). The organic layer was collected and the aqueous solution extracted further with chloroform (2 × 100 ml). The combined organic extracts were dried

(magnesium sulfate) and evaporated to give the amine (3). To a stirred solution of the amine (3) (50 mmol) and triethylamine (200 mmol) in dichloromethane (100 ml) cooled to 0 °C under argon was added a solution of an appropriate sulfonyl chloride R⁷SO₂Cl (75 mmol) in

dichloromethane (50 ml). The mixture was stirred for 1-3 h at 0 °C. Saturated sodium hydrogen solution (200 ml) was added and the organic layer collected. The aqueous solution was further extracted with chloroform (2 × 50 ml). The combined organic extracts were dried (magnesium sulfate) and evaporated. To the residue was added tetrahydrofuran (200 ml) followed by 1M hydrochloric acid (20 ml). The mixture was left at room temperature overnight. The tetrahydrofuran was evaporated (at this stage of some reactions the

cyclohexane -1,3-dione crystallized and was filtered off and recrystallized from an appropriate solvent), the aqueous solution was adjusted to pH 1 by the addition of saturated sodium hydrogen carbonate solution and extracted with chloroform (3 × 100 ml). The combined chloroform extracts were dried (magnesium sulfate) and evaporated. The residue was either chromatographed (on silica using chloroform then chloroform/methanol (97:3) as the eluant) or, in some instances, crystallized from acetone to afford the cyclohexane-1,3-dione (5). Synthesis of Cydohexane-1,3-diones (5) wherein X = COR⁷, CO₂R⁷, CONR⁷R⁸, SO₂NR⁷R⁸ or CSNR⁷R⁸

To a stirred solution of the appropriate amine (4) (50 mmol) in dichloromethane (100 ml) at 0 °C under argon was added a solution of the appropriate acylchloride R⁷COCl (or anhydride (R⁷CO)₂O) (55 mmol) or chloroformate ester R⁷OCOCl (55 mmol) or carbamoyl chloride

R⁷R⁸NCOCl(55 mmol) or dialkylsulfamoyl chloride R⁷R⁸NSO₂Cl (55 mmol) or dialkylthiocarbamoyl chloride R⁷R⁸NCSCl (55.mmol) in dichloromediane (50 ml) followed by a solution of sodium hydroxide (55 mmol) in water (20 ml). The mixture was stirred for 1-24 h at 0 °C. The reaction mixture was then worked up and subjected to acid hydrolysis (by the general procedure described above for the synthesis of cyclohexane-1,3-diones (5) wherein X = SO₂R⁷) to afford the cyclohexane-1,3-diones (5) wherein X = COR⁷, CO₂R⁷, CONR⁷R⁸, SO₂NR⁷R⁸ or CSNR⁷R⁸, respectively.

Acylation of Cydohexane-1,3-diones (5)

To a stirred solution of the cyclohexane-1,3-dione (5) (25 mmol) and DBU (1,8-diazabicyclo[5.4.0]-7-undecene) (37.5 mmol) in toluene (100 ml) was added an appropriate acyl chloride (37.5 mmol) and the mixture was stirred for 1 h at room temperature. Dilution with water (50 ml) and toluene (30 ml) and shaking the mixture gave an organic phase which was quickly washed with 1 M hydrochloric acid (37.5 ml), dried (magnesium sulfate) and evaporated. The residue and 4-dimethylaminopyridine (8.25 mmol) were heated under reflux in toluene (50 ml) for 3 h (or until thin layer chromatography showed that the reaction was complete) and then the toluene was removed in vacuo and the residue chromatographed on silica using chloroform as the eluant to give the C-acylated compound (6). Oximation of the C-acylated Compounds (6)

Method 1

A mixture of the C-acylated compound (6) (3 mmol), the appropriate O-substituted hydroxylamine hydrochloride (3.6 mmol), pyridine (3 ml) and ethanol (20 ml) was stirred at room temperature for 24 h, and then the solvents were evaporated in vacuo. Water (20 ml) was added to the residue. Acidification of the mixture to pH 2 with 3M hydrochloric acid, extraction with diethyl ether, evaporation of the dried (magnesium sulfate) organic phase and chromatography of the residue on silica using dichloromethane and then dichloromethane/methanol (98:2) as the eluant afforded examples of compounds of the invention of formula (1).

Method 2

A mixture of the appropriate O-substituted N-hydroxyphthalimide (3.60 mmol), N,N-diethylethylenediamine (3.60 mmol), ethanol (10 ml) and chloroform (3 ml) was stirred for 1 h at room temperature. A solution of the C-acylated compound (6) (3 mmol) is ethanol (9 ml) and chloroform (1 ml) was added and the mixture stirred at room temperature for 24 h. The reaction mixture was worked up as described in Method 1 to afford examples of compounds of the invention of formula (1).

The melting points of selected compounds of formula (1) of the invention are given in Tables 1-9.

The 100MHz ¹H-NMR spectra of selected compounds of formula (1) of the invention (measured in CDCl₃ with tetramethylsilane as internal standard) listed below are consistent with the stated structures: Cpd 1.22: δ 15.0, s, OH; 4.08, q, J6Hz, OCH₂Me; 3.30-2.00, m, 11H; 2.9, s, NMe; 1.80-1.20, m, 2H; 1.32, t, J7Hz, SO₂CH₂Me or OCH₂Me; 1.30, t,

SO₂CH₂Me or OCH₂Me; 0.96, t, J6Hz, CH₂CH₂Me. Cpd 1.24: δ 13.9, s, OH; 7.40-7.10, m, 4H; 5.00, s, OCH₂; 3.30-2.00, m, 11H; 2.85, s, NMe; 1.70-1.30, m, 2H; 1.30, t, J6Hz, SO₂CH₂Me; 0.94, t, J6Hz,

CH₂CH₂Me. Cpd 2.7: δ 14.2, s, OH; 7.40-7.10, m, 4H; 5.00, s, OCH₂; 3.30-2.00, m, 11H; 2.83, s, NMe; 1.30, t, J6Hz, SO₂CH₂Me; 1.10, t, J6Hz, CNCH₂Me.

Cpd 3.5: δ 13.7, s, OH; 8.20, d, J8Hz, 2H; 7.49, d, J8Hz, 2H; 5.13, s, OCH₂; 4.25-3.85, m, CHMe; 3.05-1.37, m, 11H; 1.80, s, NMe or SO₂Me; 1.70, s, NMe or SO₂Me; 1.17, d, J6Hz, CHMe; 0.94, t, J6Hz, CH₂Me.

Cpd 3.6: δ 13.9, s, OH; 6.08, t, J6Hz, CH = CCl₂; 4.61, d, J6Hz, OCH₂, 4.30- 3.85, m, CHMe; 3.10-1.28, m, 11H; 2.82, s, NMe or SO₂Me; 2.72, s, NMe or SO₂Me; 1.15, d, J6Hz, CHMe; 0.94, s, CH₂Me.

Cpd 3.8: δ 14.4, s, OH; 6.20-5.70, m, CH= CH₂; 5.45-5.15, m, CH = CH₂; 4.47, d,

J6Hz, OCH₂; 3.82, quintet, J7Hz, NCH; 3.10-1.90, m, 7H; 2.82, s, SO₂Me; 2.67, s, NMe; 1.75-1.25, m, 6H; 0.92, t, J7Hz, 2Me. Cpd 3.9: δ 12.8, s, OH; 6.05, t, J7Hz, CH=CCl₂; 4.60, d, J7Hz, OCH₂; 3.82, quintet, J7Hz, NCH; 3.05-1.95, m, 7H; 2.82, s, SO₂Me; 2.67, s, NMe; 1.80-1.25, m, 6H; 0.92, t, J7Hz, 2CH₂Me.

Cpd 3.11: δ 14.0, s, OH; 8.21, d, J8Hz, 2H; 7.49, d, J8Hz, 2H; 5.13, s, OCH₂; 3.80, quintet, J7Hz, NCH; 3.05-1.90, m, 7H; 2.82, s, SO₂Me; 2.67, s, NMe; 1.80- 120, m, 6H; 0.95, t, J7Hz, Me; 0.92, t, J7Hz, Me.

Cpd 3.12: δ 15..2, s, OH; 4.04, q, J7Hz, OCH₂; 3.82, quintet, J7Hz, NCH; 2.95-1.95, m, 7H; 2.82, s, SO₂Me; 2.67, s, NMe; 1.75-1.30, m, 6H; 1.30, t, OCH₂Me; 0.82, t, J7Hz, 2Me.

Cpd 3.14: δ 14.6, s, OH; 4.08, q, 2H, J7Hz; 2.81, s, NMe or SO₂Me; 2.75, s, NMe or SO₂Me;3.25-1.07, m, 15H; 1.27, t, J7Hz, OCH₂Me; 0.92, t, J6Hz, CH₂CH₂Me. Cpd 3.15: δ 14.5, s, OH; 6.20-5.70, m, CH= CH₂; 5.45-5.15, m, CH = CH₂; 4.48, d, J6Hz, OCH₂; 3.30-1.13, m, 15H; 2.80, s, NMe or SO₂Me; 2.74, s, NMe or SO₂Me; 0.93, t, J6Hz, CH₂Me Cpd 4.1: δ 15.2, s, OH; 4.06, q, J7Hz, OCH₂; 4.15-3.80, m, NCH; 3.00-1.80, m, 7H; 2.86, s, NMe₂; 2.63, s, NMe; 1.75-1.30, m, 4H; 1.28, t, J7Hz, OCH₂Me; 1.17, d, J7Hz, CHMe; 0.94, t, J7Hz, Me.

Cpd 4.2. δ 15.0 s, OH; 6.18-5.70, m, CH=CH₂; 5.48-5.16, m, CH = CH₂; 4.49, d, J6Hz, OCH₂; 4.18-3.72, m, NCH; 3.00-1.90, m, 7H; 2.75, s, NMe₂; 2.67 s, NMe; 1.75-1.25, m, 4H; 1.15, d, J7Hz, CHMe; 0.94, t, J7Hz, CH₂Me.

Cpd 4.4: δ 15.1; s, OH; 4.05, q, J7Hz, OCH₂; 4.2-3.8, m, NCH; 3.50-1.85, m, 11H; 2.63, s, NMe; 1.85-1.3, m, 4H; 1.28, t, J7Hz, OCH₂Me; 1.16, d, J7Hz, CHMe; 1.07, t, J7Hz, N(CH₂Me)₂; 0.94, t, J7Hz, CH₂CH₂Me.

Cpd 4.5: δ 14.8, s, OH; 6.20-5.68, m, CH= CH₂; 5.47-5.16, m, CH = CH₂; 4.48, d,

J7Hz, OCH₂; 4.18-3.80, m, NCH; 3.40-1.84, m, 11H; 2.64, s, NMe; 1.72-1.30, m,

4H; 1.14, d, J7Hz, CHMe; 1.10, t, J7Hz, N(CH₂Me)₂; 0.93, t, J7Hz, CH₂CH₂Me.

Cpd 4.6: δ 14.2, s, OH; 7.40-7.10, m, 4H; 4.98, s, OCH₂; 4.18-3.73, m, NCH;

3.35-1.85, m, 11H; 2.63, s, NMe; 1.72-1.28, m, 4H; 1.15, d, J7Hz, CHMe; 1.10, t, J7Hz, N(CH₂Me)₂; 0.94, t, J7Hz, CH₂CH₂Me. Cpd 5.8: δ 14.6, s, OH; 6.20-5.70, m, CH= CH₂; 5.30, m, CH = CH₂; 4.98, d, J6Hz, OCH₂; 3.30-2.00, m, 13H; 2.82, s, NMe; 1.80-1.30, m, 2H; 1.10, t, J6Hz, N(CH₂Me)₂; 0.94, t, J8Hz, CH₂CH₂Me

Cpd 5.9. δ 13.6, s, OH; 7.45-7.15, m, 4H; 4.98, s, OCH₂; 3.40-2.70, m, 6H; 2.80, s, NMe; 2.70-1.90, m, 7H; 1.90-1.30, m, 2H; 1.10, t, J6Hz, N(CH₂Me)₂; 0.91, t, J6Hz, CH₂CH₂Me.

Cpd 5.10: δ 14.3, s, OH; 6.05, t , J7Hz, CH=CCl₂; 4.62, d, J7Hz, OCH₂; 3.40-2.00, m, 13H; 2.82, s, NMe; 1.73-1.27, m, 2H; 1.12, t, J7Hz, N(CH₂Me)₂; 1.03, t, J7Hz, NCH₂CH₂Me; 0.94, t, J6Hz, CH₂CH₂Me Cpd 5.11: δ 8.20, d, J9Hz, 2H; 7.47, d, J9Hz, 2H; 5.10, s, OCH₂; 3.40-1.25, m, 15H; 2.80, s, NMe, 1.10, t, J7Hz, N(CH₂Me)₂ ; 0.92, t, J7Hz, CH₂CH₂Me.

Cpd 5.12 δ 6.17-5.66, m, CH= CH₂; 5.43-5.13, m, CH = CH₂; 4.47, d, J7Hz, OCH₂; 3.25-1.23, m, 20H; 2.78, s, NMe₂; 0.92; t, J7Hz, CH₂CH₂Me.

Cpd 5.28: δ 15.2, s, OH; 4.02, q, J6Hz, OCH₂Me; 3.30-1.40, m, 20H; 2.78, s, NMe₂; 1.28, t, J6Hz, OCH₂Me; 0.92, t, J6Hz, CH₂CH₂Me. Cpd 5.33: δ 14.6, s, OH; 6.20-5.70, m, CH= CH₂; 5.45-5.17, m, CH = CH₂; 4.49, d, J6Hz, OCH₂; 3.67, septet, J7Hz, NCH; 3.10-1.85, m, 9H; 2.84, s, NMe₂; 1.82-1.30, m, 2H; 1.09, d, J7Hz, CHMe₂; 0.93, t, J7Hz, CH₂Me.

Cpd 5.37: δ 9.55, s, OH; 4.02, q, J6Hz, OCH₂Me; 3.40-1.03, m, 23H; 1.32, t, J6Hz, OCH₂Me or NCH₂Me; 1.10, t, J6Hz, OCH₂Me or NCH₂Me; 0.93, t, J6Hz, CH₂CH₂Me.

Cpd 5.44: δ 8.17, d, J8Hz, 2H; 7.47, d, J8Hz, 2H; 5.10, s, OCH₂; 3.50-1.30, m,

21H; 1.07, t, J6Hz, NCH₂Me; 0,94, t, J6Hz, CH₂CH₂Me.

Cpd 5.45: δ 6.07, t, J6Hz, CH = CCl₂; 4.63, d, J6Hz, OCH₂; 3.57-1.30, m, 21H;

1.13, t, J6Hz, NCH₂Me; 0.94, t, J6Hz, CH₂CH₂Me.

Cpd 5.48: δ 14.5, s, OH; 6.17-5.70, m, CH=CH₂; 5.43-5.14, m, CH = CH₂; 4.48, d, J6Hz, OCH₂; 3.62, septet, J6Hz, CHMe₂; 3.23, q, J7Hz, N(CH₂CH₃)₂; 3.05-1.25, m, 11H; 1.10, t, J7Hz, N(CH₂Me)₂; 1.05, d, J7Hz, CH(Me)₂; 0.93, t, J7Hz, CH₂CH₂Me.

Cpd 5.50: δ 4.09, q, J6Hz, OCH₂; 3.67, t, J6Hz, CH₂OCH₂; 3.35-3.05, m, 6H; 2.88, s, NMe; 3.00-1.95, m, 7H; 1.80-1.30, m, 2H; 1.30, t, J6Hz, OCH₂Me; 0.97, t, J6Hz, CH₂CH₂Me.

Cpd 6.8: δ 15.3 s, OH; 4.06, q, J7Hz, OCH₂; 3.50-3.20, m, NCH₂; 3.05-2.80, m, 2H; 2.99, s, NMe; 2.75-1.97, m, 7H; 1.85-1.25, m, 2H; 1.26, t, J7Hz, OCH₂Me; 1.13, t, J7Hz, COCH₂Me; 0.94, t, J7Hz, CH₂CH₂Me. Cpd 6.9: δ 14.0, s, OH; 4.07, q, J7Hz, OCH₂; 3.50-3.20, m, NCH₂; 3.05, s, NMe; 3..03-2.2, m, 8H; 1.80-1.30, m, 2H; 1.28, t, J7Hz, OCH₂Me; 1.12, d, J7Hz, CHMe₂; 0.95, t, J7Hz, CH₂CH₂Me. Cpd 6.10: δ 14.9, s, OH; 6.17-5.70, m, CH= CH₂; 5.45-5.18, m, CH = CH₂; 4.47, d, J6Hz, OCH₂; 3.50-3.18, m, NCH₂; 3.00, s, NMe; 3.05-2.74, m, 2H; 2.72-2.05, m, 7H; 1.80-1.30, m, 2H; 1.12, t, J6Hz, COCH₂Me; 0.95, t, J6Hz, CH₂CH₂Me.

Cpd 6.14. δ 14.8, s, OH; 6.16-5.66, m, CH= CH₂; 5.45-5.15,m, CH = CH₂; 4.48, d, J6Hz, OCH₂; 3.48-1.30, m, 18H; 2.90, s, NMe; 0.93, t, J6Hz, CH₂CH₂Me.

Cpd 6.18: δ 14.2, s, OH; 8.20, d, J8Hz, 2H; 7.50, d, J8Hz, 2H; 5.13, s, OCH₂; 3.60-1.30, m, 18H; 2.90, s, NMe; 0.93, t, J6Hz, CH₂Me. Cpd 6.27: δ 14.4, s, OH; 6.20-5.70, m, CH= CH₂; 5.45-5.15, m, CH = CH₂; 4.48, d, J6Hz, OCH₂; 4.07, septet, J6Hz, CHMe; 3.43-1.30, m, 15H; 1.18, d, J6Hz, 2CHMe; 1.13, t, J6Hz, COMe; 0.93, t, J7Hz, CH₂CH₂Me.

Cpd 6.28: δ 14.8,s, OH; 4.08, q, J7Hz, OCH₂CH₃; 3.30-1.30, m, 14H; 1,29, t, J7Hz, COMe or OCH₂Me; 1.18, d, J6Hz, 2CHMe; 1.15, t, J6Hz, COMe or OCH₂Me; 0.94, t, J6Hz, CH₂CH₂Me.

Cpd 6.33: δ 6.23-5.66, m, CH=CH₂; 5.46-5.13, m, CH = CH₂; 4.50, d, J7Hz,

OCH₂; 3.56-1.26, m, 20H; 2.10, s, COMe; 0.94, t, J6Hz, CH₂Me.

Cpd 6.38: δ 14.3, s, OH; 6.20-5.70, m, CH= CH₂; 5.45-5.15, m, CH = CH₂; 4.47, d, J6Hz, OCH₂; 3.60-1.93, m, 9H; 3.16, s, NMe; 1.93-1.21, m, 3H; 1.10-0.50, m, 4H; 0.93, t, J6Hz, CH₂Me Cpd 6.44. δ 14.5, s, OH; 7.25, s, 4H; 6.20-5.70, m, CH= CH₂; 5.45-5.15, m,

CH = CH₂; 4.48, d, J6Hz, OCH₂; 3.70-1.20, m, 11H; 2.97, s, NMe; 0.94, t, J6Hz, CH₂CH₂Me. Cpd 6.47: δ 14.7, s, OH; 7.47-7.23, m, 2H; 7.08-6.95, m, 1H; 6.20-5.70, m, CH=CH₂; 5.45-5.15, m, CH = CH₂; 4.47, d, J6Hz, OCH₂; 3.65-2.0, m, 9H; 3.20, s, NMe; 1.77-1.27, m, 2H; 0.92, t, J8Hz, CH₂Me. Cpd 6.49: δ 15, s, OH; 6.20-5.66, m, CH=CH₂; 5.50-5.10, m, CH = CH₂; 4.50, d, J6Hz, OCH₂; 3.50-3.20, m, CH₂; 3.10-1.85, m, 7H; 3.00, s, NMe; 2.06, s, COMe; 1.80-1.20, m, 2H; 0.93, t, J6Hz, CH₂Me.

Cpd 6.50: δ 4.06, q, J7Hz, OCH₂Me; 3.45-3.20, m, 2H; 3.05-1.30, m, 9H; 3.00, s, NMe; 2.06, s, COMe; 1.28, t, J6Hz, OCH₂Me; 0.93, t, J6Hz, CH₂Me.

Cpd 7.2: δ 14.8, s, OH; 6.20,-5.70, m, CH= CH₂; 5.46-5.16, m, CH = CH₂; 4.49, d, J6Hz, OCH₂; 3.67, s, OMe; 3.38-3.09, m, NCH₂; 3.03-2,75, m, 2H; 2.91, s,

NMe; 2.70-1.95, m, 5H; 1.80-1.25, m, 2H; 0.95, t, J7Hz, CH₂Me.

Cpd 7.10: δ 13.9, s, OH; 4.63, d, J2Hz, OCH₂; 3.67, s, OMe; 3.40-2.00, m, 10H;

2.92, s, NMe; 1.80-1.20, m, 2H; 0.92, t, J7Hz, CH₂CH₂Me.

Cpd 7.13: δ 14.6, s, OH; 6.20-5.70, m, CH=CH₂; 5.46-5.15, m, CH=CH₂; 4.48, d, J6Hz, OCH₂; 4.10, q, J6Hz, OCH₂Me; 3.40-3.15, m, 2H; 3.00-2.15, m, 7H; 2.90, s, NMe; 1.82-1.33, m, 2H; 1.23, t, J6Hz, OCH₂Me; 0.94, t, J6Hz,

CH₂CH₂Me.

Cpd 8.3: δ 13.3, s, OH; 6.17-5.70, m, CH= CH₂; 5.44-5.18, m, CH = CH₂; 4.49, d, J6Hz, OCH₂; 3.20-1.80, m, 9H; 2.78, s, NMe and NMe₂; 1.75-1.27, m, 2H; 0.93, t, J7Hz, CH₂Me.

Cpd 8.4. δ 13.8, s, OH; 6.05, t, J6Hz, CH= CCl₂; 4.60, d, J6Hz, OCH₂; 3.27- 2.00, m, 9H; 2.78, s, NMe and NMe₂; 1.75-1.25, m, 2H; 0.93, t, J7Hz, CH₂Me.

Cpd 8.6. δ 14.6, s, OH; 4.57, d, J2Hz, OCH₂; 3.30-2.00, m, 10H; 2.78, s,

3NMe; 1.80-1.25, m, 2H; 0.92, t, J6Hz, CH₂CH₂Me. Cpd 8.8: δ 14.6, s, OH; 6.20-5.70, m, CH= CH₂; 5.42-5.15, m, CH =CH₂; 4.49, d, J6Hz, OCH₂; 3.80, septet, J6Hz, CHMe₂; 3.20-1.30, m, 11H; 2.73, s, NMe₂; 1.17, d, J7Hz, CH(Me)₂; 0.92, t, J8Hz, CH₂CH₃. Cpd 9.3: δ 12.2, s, OH; 8.20, d, J9Hz, 2H; 7.50, d, J9Hz, 2H; 5.13, s, OCH₂; 3.64, broad d, J6Hz, NCH₂; 3.07, s, NMe₂; 3.02-2.75, m, 2H; 2.99, s, NMe; 2.70-2.00, m, 5H; 1.80-1.31, m, 2H; 0.95, t, J7Hz, CH₂Me.

Activity of Compounds of the Invention

Test results indicate that the compounds of the invention are highly active pre-emergent and/or post-emergent herbicides or plant growth regulants.

These compounds are particularly useful for controlling certain grass and broadleaf weeds in small grain cereals such as wheat (Triticum aestivum) and barley (Hordeum vulgare), examples of which include, but are not limited to, Centurk wheat, Era wheat, Igri barley and Klages barley. Many of the compounds of this invention are especially useful for the control of selected grass weeds, such as wild oats (Avena fatua), black grain (Alopecurus myosoides), crabgrass (Digitaria sanguinalis), foxtails (Setaria spp.) and Italian ryegrass (Lolium multiflorum). Some of these compounds are useful for controlling certain grass and broadleaf weeds in dryland and paddy rice (Orysa sativa), examples of which include, but are not limited to, Indica and Japonica varieties of the crop. Many of the compounds of this invention are especially useful for the control of selected grass weeds, such as barnyardgrass

(Echinochloa crusgalli), in paddy rice.

At the appropriate application rates, these compounds also have utility for broad-spectrum pre- and/or post-emergence weed control in areas where control of all vegetation is required. Alternatively, these compounds are useful to regulate plant growth.

Rates of application for compounds of this invention are determined by a number of factors. These factors include formulation selection, method of application, amount of vegetation present, growing conditions, etc. In general, the subject compounds should be applied at rates of 0.05 to 10 kg/ha with a preferred rate range of 0.1 to 2 kg/ha. One skilled in the art can easily determine application rates necessary for the desired level of weed control.

Compounds of this invention may be used alone or in combination with other commercial herbicides. Accordingly, a further embodiment of the invention provides a herbicidal composition comprising a mixture of at least one herbicidal compound of formula (1) as hereinbefore defined with at least one other herbicide. In a further embodiment, the invention provides a method for regulating the growth of a plant comprising applying to the plant, to the seed of the plant, or to the growth medium of the plant an effective amount of a compound of Formula (1) hereinbefore defined. Rates of application of these compounds can be influenced by many factors of the environment and should be determined under actual use conditions. Weed grasses in graminaceous crops can normally be killed when treated at a rate of from less than 0.1 to about 20 kg active ingredient/ha. The compounds of this invention can also be mixed with fungicides, bactericides, acaricides, nematicides, insecticides, or other biologically active compounds. Amounts of these biologically active materials added for each part by weight of the composition of this invention may vary from 0.05 to 25 parts by weight. Suitable agents of this type are well known to those skilled in the art.

Formulation

Useful formulation of the compounds within the scope of this invention can be prepared in conventional ways. They include dusts, granules, pellets, solutions, emulsions, wettable powders, emulsifiable concentrates and the like. Many of these may be applied directly. Sprayable formulations can be extended in suitable media and used at spray volumes of from one litre to several hundred litres per hectare. High strength compositions are primarily used as intermediates for further formulations. The formulations, broadly, contain about 1% to 99% by weight of active ingredient(s) and at least one of (a) about 0.1% to 20% surfactant(s) and (b) about 5% to 99% solid or liquid inert diluent(s). More specifically, they will contain these ingredients in the following approximate proportions:

Percent by Weight

Active

Ingredient Diluent(s) Surfactant(s)

Wettable Powders 20-90 0-74 1-10

Oil Suspensions, Emulsions, 5-50 40-95 0-15

Solutions (including Emulsifiable Concentrates)

Aqueous Suspensions 10-50 40-84 1-20

Dusts 1-25 70-99 0-5

Granules and Pellets 1-95 5-99 0-15

High Strength Compositions 90-99 0-10 0-2

Lower or higher levels of active ingredients can, of course, be present depending on the intended use and the physical properties of the compound. Higher ratios of surfactant to active ingredient are sometimes desirable and are achieved by incorporation into the formulation or by tank mixing.

The compositions may be in the form of dusting powders or granules comprising the active ingredient and a solid diluent or carrier therefor, for example, kaolin, bentonite, kieselguhr, dolomite, calcium carbonate, talc, powdered magnesia, Fuller's earth, gypsum, Hewill's earth, diatomaceous earth, and China clay. The compositions may also be in the form of dispersible powders or grains comprising a wetting agent to facilitate the dispersion in liquids of the powder or grains which may contain also solid diluents, fillers and suspending agents.

Typical solid diluents are described in Watkins, et al., "Handbook of Insecticide Dust Diluents and Carriers", 2nd Ed., Dorland Books, Caldwell, N.J. The more absorptive diluents are preferred for the wettable powders and the denser ones for dusts. All formulations can contain minor amounts of additives to reduce foam, caking, corrosion, microbiological growth, etc.

Compositions for dressing seed, for example, may contain an agent (for example a mineral oil) for assisting the adhesion of the composition to the seed.

The aqueous dispersions or emulsions may be prepared by dissolving the active ingredient(s) in an organic solvent optionally containing wetting, dispersing or emulsifying agent(s) and then adding the mixture to water which may also contain wetting, dispersing or emulsifying agent(s). Suitable solvents are acetone, ethylene dichloride, isopropyl alcohol, propylene glycol, diacetone alcohol, toluene, kerosene, methylnaphthalene, the xylenes and

trichloroethylene amongst others. Solubility under 0.1% is preferred for suspension concentrates; solution concentrates are preferably stable against phase separation at 0 °C. "McCutcheon's Detergents and Emulsifiers Annual", MC Publishing Corp., Ridgewood, N.J., as well as Sisely and Wood,

"Encyclopedia of Surface Active Agents", Chemical Publishing Co., Inc., New York, 1964, list surfactants and recommended uses.

The methods of making such compositions are well known. Solutions are prepared by simply mixing the ingredients. Fine solid compositions are made by blending and, usually, grinding as in a hammer or fluid energy mill.

Suspensions are prepared by wet milling (see, for example, Littler, US Pat. No. 3,060,084). Granules and pellets may be made by spraying the active material upon preformed granular carriers or by agglomeration techniques.

To demonstrate the effectiveness of compounds of Formula (1) of the present invention as herbicidal agents, compounds of Formula (1) were applied to wild oats, wheat, barnyardgrass and rice postemergent at 0.1 and 0.4 kg/hectare. The herbicidal data for selected compounds of formula (1) of the invention are shown in Tables 10 and 11. In these Tables 0 signifies no effect and 10 signifies plant dead. As can be seen many of the compounds of Formula (1) selectively control wild oats in wheat, and some selectively control barnyardgrass in rice.

TABLE 10

Cpd Wild Oats Wheat Wild Oats Wheat

0.1Kg/Ha 0.1KgIHa 0.4KgIHa 0.4KglHa

1.10 8 0 9 0

1.22 9 0 10 0

1.23 9 0 10 0 1.24 10 0 10 2

1.25 9 2 10 3

1.40 2 0 10 1

2.7 2 0 4 0

3.5 9 1 10 2 3.6 4 1 9 2

3.8 5 1 10 3

3.9 3 1 9 1

3.11 9 2 10 2

3.12 9 3 10 2 3.14 9 2 10 5

3.15 9 3 10 5

4.1 9 2 10 5

4.2 7 2 10 4 4.4 8 2 10 3 4.5 9 0 10 4

4.6 7 1 9 2

5.8 10 1 10 5

5.9 1 0 9 2

5.10 1 0 9 2 5.11 1 1 9 1

5.12 4 0 9 3

5.28 8 0 9 2 5.32 9 3 10 2

5.33 9 0 10 4

5.37 5 0 9 3

5.44 7 1 9 3 5.45 5 0 9 1

5.48 9 1 10 2

5.50 5 0 10 2

6.8 1 0 10 3

6.9 3 0 10 4 6.10 2 0 10 5

6.11 2 1 10 4

6.14 0 1 9 0

6.18 1 0 10 1

6.27 4 0 9 2 6.28 5 0 10 1

6.33 3 0 9 1

6.38 5 2 10 3

6.44 2 1 9 3

6.47 5 0 9 2 6.49 2 0 10 3

6.50 2 0 9 3

7.2 5 0 10 6

7.10 2 0 10 2

7.13 1 0 10 2 8.3 5 0 10 4

8.4 2 1 10 2

8.6 4 0 10 2

8.8 3 0 10 2

9.3 5 2 10 3 TABLE 11

Cpd Barnyardgrass Rice Barnyardgrass Rice

0.1Kg/Ha 0.1Kg/Ha 0.4KglHa 0.4KglHa

1.66 3 1 9 1

1.67 10 1 10 3

1.74 10 1 10 1

1.75 10 3 10 4

1.76 10 1 10 3

3.13 4 0 10 0

3.16 9 2 10 3

4.3 4 0 9 1

5.32 4 0 10 3

5.41 9 2 10 4

5.46 3 0 9 0

5.53 10 2 10 4

5.56 10 1 10 2

5.57 10 0 10 2

5.59 10 0 10 2

7.26 10 1 10 1

7.27 10 1 10 1

9.5 9 0 10 3

Claims

CLAIMS:

1. Compounds of the formula (1) or isomeric and/or tautomeric forms thereof:

wherein

R¹ is H, C₁-C₄ alkyl, _C2-C₄ alkenyl, C₂-C₄ alkynyl or M; R² is C₁-C₄ alkyl; R³ is C₁-C₄ alkyl, C₂-C₄ alkenyl, C₂-C₄ alkenyl with 1-3 halogen substituents, C₂-C₄ alkynyl; phenyl optionally substituted with 0-3 substituents selected from the group consisting of halogen, C₁-C₄ alkyl, C₁-C₄ alkoxy, C₁-C₄ alkythio, C₁-C₄ haloalkyl, C₁-C₄ haloalkoxy, nitro, cyano, phenyl (optionally substituted with 0-3 substituents selected from the group consisting of halogen, C₁-C₄ alkyl, C₁-C₄ alkoxy, C₁-C₄ haloalkyl, C₁-C₄ haloalkoxy, nitro, and cyano) and phenoxy

(optionally substituted with 0-3 substituents selected from the group consisting of halogen, C₁-C₄ alkyl, C₁-C₄ alkoxy, C₁-C₄ haloalkyl, C₁-C₄ haloalkoxy, nitro, and cyano); R⁴ and R⁵ are independently H, or C₁-C₄ alkyl, C₂-C₄ alkenyl;

or

R⁷ and R⁸ together with the nitrogen to which they are attached form a fully saturated- or an unsaturated 5- to 7-membered heterocyclic ring contaimng 1-3 heteroatoms selected from the group consisting of 1-3 nitrogen, 0-2 oxygen and 0-2 sulfur atoms; n is 0, 1, 2, 3, 4 or 5; provided that when n = 0, then X is not COR⁷, CO₂R⁷ or CONR⁷R⁸; and M is Li⁺, Na⁺, K⁺, NH₄ ⁺ , or N(R¹¹)₄ ⁺ where R¹¹ is C₁-C₄ alkyl.

2. Compounds as claimed in claim 1, characterised in that they have the formulae depicted and defined in any one of Tables 1 to 9 herein.

3. Compounds as claimed in claim 1, characterised in that X is -SO₂R⁷.

4. Compounds as claimed in claim 1, characterised in that X is

-CONR⁷R⁸.

5. Compounds as claimed in claim 1, characterised in that X is -COR⁷.

6. Compounds as claimed in claim 1, characterised in that X is -CO₂R⁷.

7. Compounds as claimed in claim 1, characterised in that X is

-SO₂NR⁷R⁸.

8. Compounds as claimed in claim 1, characterised in that X is

-CSNR⁷R⁸.

9. A process for preparing a compound of the general formula (1) as stated and defined in claim 1, characterized in that a compound of the general formula (6):

wherein R², R⁴, R⁵, R⁶, n and X are as defined in claim 1, is reacted with an O-substituted hydroxylamine of the formula:

R³CH₂ONH₂ wherein R³ as defined in claim 1, to yield a compoimd of formula (1), wherein R¹ = H and thereafter, if desired, converting the compound thus obtained by a known method to a compound in which R¹ is other than H.

10. A process as claimed in claim 9, characterized in that the compound of formula (6) is prepared by acylating and isomerizing a compound of formula (5):

wherein R⁴, R⁵, R⁶, n and X are as defined in claim 1, by a Fries

rearrangement.

11. A process as claimed in claim claim 10, characterised in that the compoimd of formula (5) is prepared by acid hydrolysis of a compound of formula (4),

wherein R⁴, R⁵, R⁶, n and X are as defined in claim 1, as R⁹ is a C₁-C₆ alkyl group.

12. A process as claimed in claim 11, characterised in that the compound of formula (4) is prepared by the reaction of a compound of formula (3)

wherein R⁴, R⁵, R⁶, n and R⁹ are as defined in claim 11, and

(a) a sulphonyl chloride, R⁷SO₂Cl, to give the compound (4) in which

X = -SO₂R⁷, or

(b) an acid chloride, R⁷COCl, or anhydride, (R⁷CO)₂O, to give the compound (4) in which X = -COR⁷, or

(c) a chloroformate ester, R⁷OCOCl, to give the compound (4) in which

X = -CO₂R⁷, or

(d) a carbamoyl chloride, R⁷R⁸NCOCl, or isocyanate, R⁷NCO, to give the compound (4) in which X = -CONR⁷R⁸

(e) a dialkylsulfamoyl chloride, R⁷R⁸NSO₂Cl, to give the compound (4) in which X = - SO₂NR⁷R⁸

(f) a dialkylthiocarbamoyl chloride, R⁷R⁸CSCl, to give the compound (4) in which X = CSNR⁷R⁸.

13. A process as claimed in claim 12, characterised in that the compound of formula (3) is prepared by reducing a compound of formula (2)

wherein R⁴, R⁵, R⁶, n and R⁹ are as defined in claim 11, with an alkali metal in liquid ammonia.

14. A plant growth inhibiting, plant damaging, or plant killing

composition comprising a compound formula (1), as defined in claim 1, and an inert carrier therefor.

15. A method for regulating the growth of a plant which process comprises applying to the plant, to the seed of the plant, or to the growth medium of the plant, an effective amount of a compound of formula (1), as defined in claim 1.

16. A method for selectively inhibiting, damaging or killing weed grasses in a crop which comprises applying to the crop or its locus an effective amount of a compound of formula (1), as defined in claim 1.

17. A composition as claimed in claim 14, which includes at least one other herbicide.

18. A plant growth regulating composition comprising a compound of formula (1), as defined in claim 1, and an inert carrier therefor.

19. The use of a compound of formula (1) as herbicide or plant growth regulator.

20. A compound of formula (6) as stated and defined in claim 9.