WO1997018196A1 - Herbicidal substituted pyrazole compounds - Google Patents

Abstract

Herbicidal compositions containing substituted pyrazole compounds and derivatives thereof of formula (Ia), wherein Y is O or S and Z is a carbon-carbon single bond, O, S, C=O or C=N. Methods of controlling undesirable vegetation using these compounds and derivatives are also disclosed. Herbicidal compounds wherein Z is a carbon-carbon single bond, S, C=O or C=N are also described.

Description

HERBICIDAL SUBSTITUTED PYRAZOLE COMPOUNDS

CROSS-REFERENCE TO RELATED APPLICATIONS

This application claims the benefit of U S provisional application number 60/019.403, filed November 15, 1995

FIELD OF THE INVENTION

In one aspect, this invention relates to novel substituted pyrazole compounds and deπvatives thereof which exhibit unexpectedly desirable herbicidal activity In other aspects, this invention relates to herbicidal compositions containing a substituted pyrazole compound or derivative thereof and an agriculturally acceptable earner and to a method of controlling undesirable vegetation by applying to an area where control is desired an herbicidally effective amount of a substituted pyrazole compound or derivative thereof

BACKGROUND OF THE INVENTION

The need for effective herbicides needs no special emphasis The control of weeds and undesirable vegetation is of great economic importance since weed competition inhibits the production of foliage, fruit or seed of agπcultural crops The presence of weeds can reduce harvesting efficiency and the quality of the harvested crop Weeds on non-cropped areas may cause a fire hazard, undesirable drifting of sand or snow, and/or irntation to persons with allergies Thus, suppression of undesirable weed growth is very advantageous

Accordingly, it is an object of this invention to provide effective novel herbicidal compounds, as well as to provide novel herbicidal compositions and novel methods of controlling weeds

SUMMARY OF THE INVENTION

In one aspect, this invention is directed to compounds of formula (I)

wherein

R¹ is optionally substituted C C₆ alkyl or d-C₆ haloalkyl,

R² is optionally substituted d- β alkyl, Cι-C₆ haloalkyl or d-C₆ cycloalkyl,

R^' is hydrogen, halogen, Ci-Cό alkyl or Cι-C_ή haloalkyl,

R⁴ is optionally substituted Ci-Cβ alkyl, Cι-C₆ haloalkyl, optionally substituted Cι-C₆ alkoxy, optionally substituted d-C₆ cycloalkyl, optionally substituted (Cι-C6)alkoxy(d- C6)alkyl, optionally substituted C₂-C₆ alkenyl, optionally substituted C₂-C₆ alkynyl, optionally substituted aryl, optionally substituted heteroaryl, or an optionally substituted five or six membered heterocvclic ring containing one or more heteroatoms selected from O, N or S,

R⁵ is hydrogen, optionally substituted Ci-Cβ alkyl or (Cι-C₆)alkoxy-(Cι-C6)alkyl,

R°, R⁷, R⁸ and R⁹ are independently selected from hydrogen, halogen, optionally substituted Cι-C₆ alkyl, optionally substituted C₂-C₆ alkenyl, optionally substituted C₂-Cβ alkynyl, optionally substituted Cι-C₆ alkoxy, (Cι-C₆)alkoxy-(Cι-C6)alkyl, C C₆ haloalkyl, Ci-Cδ haloalkoxy, cyano, nitro, -S(O)_p-R wherein p is 0, 1 or 2 and R 10 is C C₃ alkyl or d-C haloalkyl, -OSO₂R^π wherein R¹¹ i 12 IS C,-C, alkyl, -CO₂H, -COR¹², -COOR¹² or -NHCOR¹ wherein R¹² is C C₆ alkyl, Cι-C₆ haloalkyl, optionally substituted Cι-C₆ cycloalkyl, optionally substituted aryl, optionally substituted heteroaryl, (Cι-C6)alkoxy-(Cι-C₆)alkyl or Ci-Cβ alkyltrπo, -CONR^l3R¹⁴ or -NR¹³R¹⁴ wherein R¹³ and R¹⁴ may be the same or different and are each hydrogen, C C alkyl, C]-C₆ haloalkyl, optionally substituted C₃-Q cycioalkyl, optionally substituted C₂-C_<; alkenyl, optionally substituted C -Cβ alkynyl, optionally substituted aryl, optionally substituted heteroaryl, (Cι-C6)alkoxy-(Cι-C6)alkyl or Cι-C₆ alkylthio, or R¹³ and R¹⁴ together with the N to which they are bound may form a ring having 3-8 members, one or more of which may be O, S or N, and

Y is O or S,

X is a carbon-carbon single bond, S, C=O or C=N,

and agriculturally acceptable salts thereof

In another aspect, this invention is directed to an herbicidal composition containing (A) a compound of formula (la)

wherein R¹, R², R³, R⁴, R⁵, R^ό, R⁷, R⁸. R⁹, A and Y have the same meanings as above and Z is a carbon-carbon single bond, O, S, C=O or C=N, or an agnculturally acceptable salt thereof, and

(B) a earner therefor

In still another aspect, this invention is directed to a method for controlling undesirable vegetation by applying to an area where such vegetation control is desired an herbicidally effective amount of a compound of formula (la)

wherein R¹, R², R³, R⁴, R⁵, R⁶, R⁷, R⁸, R⁹, A, Y and Z have the same meanings as above, or an agnculturally acceptable salt thereof

DETAILED DESCRIPTION OF THE INVENTION

The novel herbicidal compounds of this invention are of the formula (I)

wherein R¹, R², R³, R⁴, R⁵, R⁶, R⁷, R⁸, R⁹, A, Y and X have the same meanings as above, and agriculturally acceptable salts thereof

Preferably, R¹ is Ci-d, alkyl or Ci-C haloalkyl, R² is C1-C3 alkyl or C₁-C3 haloalkyl, R^J is hydrogen, and R⁵ is hydrogen

Particularly preferred compounds include N-[4-Methyl-2-[l-methyl-3- (tπfluoromethyl)-l H-pyrazol-5-yl]oxyphenyl]cyclopropane carboxamide, N-[4-Methyl-2- [ l-methyl-3-(trifluoromethyl)-lH-pyrazol-5-yl]oxyphenyl]isopropane carboxamide and N- [4-Methyl-2-[ l -methyl-3-(trifluoromethyl)-lH-pyrazol-5-yl]oxyphenyl]ethane carboxamide

In another aspect, this invention is directed to a herbicidal composition containing (A) a compound of formula (la)

wherein R¹, R², R R⁴, R⁵, R⁶, R⁷, R⁸, R⁹, A, Y and Z have the same meanings as above, or an agriculturally acceptable salt thereof; and

(B) a carrier therefor

In still another aspect, this invention is directed to a method for controlling undesirable vegetation by applying to an area where such vegetation control is desired an herbicidally effective amount of a compound of formula (la).

wherein R¹, R², R³, R⁴, R⁵, R⁶, R⁷, R⁸, R⁹, A, Y and Z have the same meanings as above, or an agriculturally acceptable salt thereof

The formulae given above are intended to include tautomeric forms of the structures drawn therein, as well as physically distinguishable modifications of the compounds which may arise, for example, from different ways in which the molecules are arranged in a crystal lattice, or from the inability of parts of the molecule to rotate freely in relation to other parts, or from geometncal isomerism, or from intra molecular or intermolecular hydrogen bonding, or otherwise.

As employed herein, the word "substituted " is intended to mean that the ^"substituted" group has one or more of the following substituents: halogen (i.e., fluorine, chlorine, bromine and iodine), C1-C4 alkyl, C₁-C4 alkylthio, C1-C4 alkoxy; (Cι-C₄)alkoxy- (Cι-C»)alkyl, (Ci-d alkoxyCO-, Cι-C₄ alkyl-S(O)_p-, nitro, nitπle, cyano, carboxy and salts, amides and esters thereof, alkanoyl of 2 to 4 carbon atoms, amino optionally substituted with one or two C1-C4 alkyl, phenyl optionally substituted with one or more C₁-C₄ alkyl, C1-C4 alkoxy, Cι-C₄alkyl-S(O)_p-, nitro, halogen, fluoπne, chloπne, bromine, cyano, or CF, groups, a five or six membered heterocyclic πng containing one or more heteroatoms selected from O, N or S, a five or six membered heterocyclic πng containing one or more heteroatoms selected from O, N or S optionally substituted with one or more C₁-C₄ alkyl, C1-C4 alkoxy, d-C alkyl-S(O)_p-, nitro, halogen, fluoπne, chloπne, bromine, cyano, or CF^ groups

The term "optionally substituted aryl" is intended to include aryl groups, such as phenyl, which are unsubstituted or are substituted with one or more of the foregoing substituents Similarly, the term "optionally substituted heteroaryl" is intended to include heteroaryl groups, such as pyndyl, pyπmidyl, tπazmyl, th enyl, furyl and thiazolyl, which are unsubstituted or are substituted with one or more of the substituents listed above

The expression "salts, amides and esters thereof used above in relation to carboxy substitution includes, for example, salts formed from alkali metals (e g , sodium, potassium and lithium), alkaline earth metais (e g , calcium and magnesium), the ammonium ion and substituted ammonium ions wherein one, two, three or four of the hydrogen atoms have been replaced by optionally substituted Cι-C₆ hydrocarbyl moieties as defined above Likewise, the carboxy substitution includes esters and amides which mav be formed from the carboxy group and an optionally substituted Cι-C₆ hvdrocarbyl moiety in the case of the ester, or an optionally substituted Ci-d- hydrocarbyl amine in the case of the amide

In the above definitions, the term "halogen ' includes fluoro, chloro, bro o and lodo groups In poiyhalogenated groups, the halogens may be the same or different

The compounds of the present invention have been found to be active herbicides, possessing utility as pre-emergence and post-emergence herbicides These compounds are useful against a wide range of plant species including broadleaf, grassy and perennial species The compounds of this invention have also been found to be paπicularly effective in controlling undesirable vegetation typically found in rice crops The terms "herbicide" and "herbicidal" are used herein to denote the inhibitive control or modification of undesired plant growth. Inhibitive control and modification include all deviations from natural development, such as, total killing, growth retardation, defoliation, desiccation, regulation, stunting, tillering, stimulation, leaf burn and dwarfing The term "herbicidally effective amount" is used to denote any amount which achieves such control or modification when applied to the undesired plants themselves or to the area in which these plants are growing. The term "plants" is intended to include germinated seeds, emerging seedlings and established vegetation, including both roots and above-ground portions.

The term "agriculturally acceptable salt" is easily determined by one of ordinary skill in the art and includes hydrohalide, acetic, sulfonic, phosphonic, inorganic and organic acid salts.

In general, the compounds of this invention may be prepared by treatment of an amine (II) with an acid chloride, acid anhydride, chlorothio formate, chlorofoimate or similar reagent in the presence of a suitable base and in a suitable solvent, according to the procedures described, for example, in J. March, Advanced Organic Chemistry, third edition, pp. 370-377, J Wiley and Sons, New York (1985) and references therein Many of these amines (II) are believed to be novel and are to be considered as yet another aspect of the present invention Alternatively amine (II) may be treated sequentially with phosgene, or a phosgene equivalent, and an appropriate alcohol or thiol to generate (la) wherein R⁵ is hydrogen Such procedures are well known in the literature (for example see Babad, H. and Zeiler. A.G., Chem Rev , 1973, 73, 75) [SCHEME 1]

SCHEME 1 (H) (Ia), R⁵ = H

Compounds of formula (la) wherein R⁵ is hydrogen may be converted readily into compounds of formula (la) wherein R⁵ is alkyl, alkoxyalkyl etc by treatment with a suitable base, such as an alkali metai hydride and an appropπate alkylating agent (such as an alkyl halide) in a suitable solvent Such reactions are well known to those skilled in the art, and need no further descπption here

The amine (II) may be prepared by reduction of the corresponding nitro compound (III), such reductions are widely descπbed in the literature Those skilled in the art will know that the reduction may be earned out using a vanety of reducing agents such as hydrogen in the presence of a catalyst, sodium borohydπde in the presence of a palladium catalyst, a sulfide or a metal such as iron in the presence of an acid, the particular method of choice will depend on. amongst other things, the compatibility of the reductants with other substituents present in the molecule References to a vaπety of methods suitable for the reduction of aromatic nitro groups may be found in H O House, Modern Synthetic Reactions, ed R Breslow, W A Benjamin Inc , New York, 1965 [SCHEME 2]

SCHEME 2

(III) (II)

When A is oxygen, the nitrobenzene of formula (III) may be prepared by reacting a compound of type (IV), where Hal is haiogen such as fluoπne or chloπne, with a hydroxypyrazole (V) The reaction is preferably earned out in an organic solvent such as N,N-dιmethylformamιde, dimethylsuifoxide, acetonitnie, a lower alcohol or a lower alkyl ketone and in the presence of a suitable base such as an alkali metal carbonate, hydroxide or alkoxide Moderate temperatures, for example from 0° to 100°C are suitably employed [SCHEME 3]

Compounds of the type (IV) are commercially available, or can be made by methods known in the literature

Hydroxypyrazoles of the type (V) can be made by methods known in the art Hydroxypyrazoies of the type (V), wherein R^J is halogen, may be made, for example by reaction of an unsubstituted pyrazole R^J is H) with a halogenating agent such as sulfuryl chloπde or N-bromosuccinimide in a suitable solvent Compounds of the type (V), (R³ is hydrogen or alkyl) may be prepared by treatment of an appropπate β-ketoester ( VT) with an alkylhydrazine in a suitable solvent, as descπbed, for example by DeStevens et al , JACS, 81. 6292, (1959) [SCHEME 4]

SCHEME 4

(VI) (V) (VII)

Such a procedure may produce a mixture of 5-hydroxy- (V) and 3-hydroxy-pyrazoles (VII), though normally these can be separated if desired by conventional punfication techniques (see, for example. L F Lee et al , J Heterocyclic Chem , 27, 243, [1990])

Compounds wherein A is sulfur may be synthesized starting with compounds of formula (V) The hvdroxy group at the 5-posιtιon of formula (V) is converted to its corresponding mercaptan In a typical reaction, compounds of formula (V) are dissolved in a suitable solvent such as toluene and a stoichiometnc excess of Lawesson's reagent [2,4- bιs(4-methoxyphenyi)-l ,3-dιthιa-2,4-diphosphetane-2,4-dιsulfide] is added The reaction mixture is heated to reflux and this temperature is maintained for about 10 hours Subsequently, the reaction mixture is cooled and stirred at room temperature for about 18 hours Next, the reaction mixture is poured into aqueous sodium carbonate, or the like, to quench the reaction The resulting aqueous phase is acidified with a strong protic acid such as concentrated hydrochloπc acid The resulting acidic solution is worked up with conventional techniques to yield the desired mercaptan of formula (VIII)

SCHEME 5

The compounds of formula VIII are treated in the same manner as compounds of formula V to produce the corresponding intermediate compound in Scheme 3, wherein the pyrazole nng is linked to the phenvl nng via a sulfur atom This sulfur intermediate is then treated as in Schemes 2 and 1 to generate the compounds of formula I and la wherein A is sulfur

The compounds of the present invention are useful as herbicides and can be applied in a vanety of ways known to those skilled in the art, at vanous concentrations The compounds are useful in controlling the growth of undesirable vegetation by pre-emergent or post-emergent application to the locus where control is desired The compositions of this invention compπse a compound of formula (la) above and a suitable earner, which earners are well known to one of ordinary skill in the art

In practice, the compounds are applied as formulations containing the vanous adjuvants and carriers known to or used in the industry for facilitating dispersion The choice of formulation and mode of application for any given compound may affect its activity, and selection will be made accordingly The compounds of the invention may thus be formulated as wettable powders, as emulsifiable concentrates, as powders or dusts, as flowables, as solutions, suspensions or emulsions, or in controlled-release forms such as microcapsules These formulations may contain as little as about 0 5% to as much as about 95% or more by weight of active ingredient The optimum amount for any given compound will depend upon the nature of plants to be controlled. The rate of application will generally vary from about 0.01 to about 1 1.5 kilograms per hectare, preferably from about 0.02 to about 4.5 kilograms per hectare.

Wettable powders are in the form of finely divided particles which disperse readily in water or other liquid carriers. The particles contain the active ingredient retained in a solid matrix. Typical solid matrices include fuller's earth, kaolin days, silicas and other readily wettable organic or inorganic solids. Wettable powders normally contain about 5% to about 95% of the active ingredient plus a small amount of wetting, dispersing, or emulsifying agent.

Emulsifiable concentrates are homogeneous liquid compositions dispersible in water or other liquid, and may consist entirely of the active compound with a liquid or solid emulsifying agent, or may also contain a liquid carrier, such as xyiene, heavy aromatic naphthas, isophorone and other nonvolatile organic solvents. In use, these concentrates are dispersed in water or other liquid and normally applied as a spray to the area to be treated. The amount of active ingredient may range from about 0.5% to about 95% of the concentrate.

Dusts are free-flowing admixtures of the active ingredient with finely divided solids such as talc, clays, flours and other organic and inorganic solids which act as dispersants and carriers.

Microcapsules are typically droplets or solutions of the active material enclosed in an inert porous shell which allows escape of the enclosed material to the surrounds at controlled rates. Encapsulated droplets are typically about 1 to 50 microns in diameter. The enclosed material typically constitutes about 50 to 95% of the weight of the capsule, and may include solvent in addition to the active compound. Shell of membrane materials include natural and synthetic rubbers, cellulosic materials, styrene-butadiene copolymers, polyacrylonitriles, polyacrylates, polyesters, polyamides, polyureas, polyurethanes and starch xanthates.

Other useful formulations for herbicidal applications include simple solutions of the active ingredient in a solvent in which it is completely soluble at the desired concentration, such as water, acetone, alkylated naphthalenes, xyiene and other organic solvents. Pressurized sprayers, wherein the active ingredient is dispersed in finely-divided form as a result of vaporization of a low boiling dispersant solvent carrier may also be used.

Many of these formulations include wetting, dispersing or emulsifying agents. Examples are alkyl and alkylaryl sulfonates and sulfates and their salts; polyhydric alcohols; polyethoxylated alcohols; esters and fatty amines. These agents when used normally comprise from 0.1% to 15% by weight of the formulation.

Each of the above formulations can be prepared as a package containing the herbicide together with other ingredients of the formulation (diluents, emulsifiers, surfactants, etc .). The formulations can also be prepared by a tank mix method, in which the ingredients are obtained separately and combined at the grower site.

The compounds of the present invention are also useful when combined with other herbicides and/or defoliants, desiccants, growth inhibitors, and the like. These other materials can comprise from about 5% to about 95% of the active ingredients in the formulations. These combinations frequently provide a higher level of effectiveness in controlling weeds and often provide results unattainable with separate formulations of the individual herbicides.

Examples of other herbicides, defoliants, desiccants and plant growth inhibitors with which the compounds of this invention can be combined are:

A. Benzo-2, l,3-thiadiazin-4-one-2,2-dioxides such as bentazone;

B. hormone herbicides, particularly the phenoxyalkanoic acids such as MCPA, MCPA-thioethyl, dichlorprop, 2,4,5-T, MCPB, 2,4-D,2,4-DB, mecoprop, trichlopyr, fluroxypyr, clopyralid, and their derivatives (e.g. salts, esters and amides);

C. pyrazole derivatives such as pyrazoxyfen, pyrazolate and benzofenap;

D. dinitrophenols and their derivatives (e.g. acetates such as DNOC, dinoterb, dinoseb and its ester, dinoseb acetate;

E. dinitroaniline herbicides such as dinitramine, trifluralin, ethalfluralin, pendimethalin; and oryzalin;

F. aryiurea herbicides such as diuron, flumeturon, metoxuron, neburon, isoproturon, chlorotoluron, chloroxuron, linuron, monolinuron, chlorobromuron, daimuron, and methabenzthiazuron; G. phenyicarbamoyloxyphenylcarbamates such as phenmedipham and desmedipham;

H. 2-phenylpyridazin-3-ones such as chloridazon, and norflurazon;

I. uracil herbicides such as lenacil, bro acil and termacil;

J. triazine herbicides such as atrazine, simazine, aziprotryne, cyanazine, prometryn, dimethametryn, simetryne, and terbutryn;

K. phosphorothioate herbicides such as piperophos, bensulide, and butamifos;

L. thiolcarbamate herbicides such as cycloate, vernolate, molinate, thiobencarb, butylate*, EPTC*, triallate, diallate, ethyl esprocarb, tiocarbazil, pyridate, and dimepiperate;

M l,2,4-triazin-5-one herbicides such as metamitron and metribuzin;

N. benzoic acid herbicides such as 2,3,6-TBA, dicamba and chloramben;

O. anilide herbicides such as pretilachlor, butachlor, the corresponding aiachlor, the corresponding compound propachlor, propanil, metazachlor, metolachlor, acetochlor, and dimethachlor;

P. dihalobenzonitrile herbicides such as dichlobenil, bromoxynil and ioxynil;

Q. haloalkanoic herbicides such as dalapon, TCA and salts thereof;

R. diphenylether herbicides such as lactofen, fluroglycofen or salts or esters thereof, nitrofen, bifenox, acifluorfen and salts and esters thereof, oxyfluorfen and fomesafen; chlornitrofen and chlomethoxyfen;

S. phenoxyphenoxypropionate herbicides such as diclofop and esters thereof such the methyl ester, fluazifop and esters thereof, haloxyfop and esters thereof, quizalofop and esters thereof and fenoxaprop and esters thereof such as the ethyl ester;

T. triketone and cyclohexanedione herbicides such as alloxydim and salts thereof, sethoxydim, cycloxydim, suicotrione, tralkoxydim, and clethodim;

U. sulfonyl urea herbicides such as chlorosulfuron, sulfometuron, metsulfuron and esters thereof; benzsulfiiron and esters thereof such as the ester thereof methyl, DPX-M6313, chlorimuron and esters such as the ethyl ester thereof, pirimisulfuron and esters such as the methyl ester thereof, DPX-LS300 and pyrazosulfuron;

V. imidazolidinone herbicides such as imazaquin, imazamethabenz, imazapyr and isopropylammonium salts thereof, imazathapyr; W arylanilide herbicides such as flamprop and esters thereof, benzoylprop- ethyl, diflufenican,

X. amino acid herbicides such as glyphosate and gluyfosinate and their salts and esters, sulphosate, and bilanafos,

Y. organoarsenical herbicides such as MSMA;

Z. herbicidal amide derivative such as napropamide, propyzamide, carbetamide, tebutam, bromobutide, isoxaben, naproanilide, diphenamid, and naptalam;

AA. 4-benzoylisoxazole and 2-cyano-l,3-dione herbicides.

BB. miscellaneous herbicides including ethofumesate, cinmethylin, difenzoquat and salts thereof such as the methyl sulfate salt, clomazone, oxadiazon, bromofenoxim, barban, tridiphane, flurochloridone, quinchlorac and mefanacet; and

CC. contact herbicides, examples of which include bipyridylium herbicides such as those in which the active entity is paraquat and those in which the active entity is diquat

* These compounds are preferably employed in combination with a safener such as 2.2-dichloro-N,N-di-2- propenylacetamide (dichlormid).

These formulations can be applied to the areas where control is desired by conventional methods Dust and liquid compositions, for example, can be applied by the use of powerdusters, boom and hand sprayers and spray dusters The formulations can also be applied from airplanes as a dust or a spray or by rope wick applications The following are examples of typical formulations 5% dust 5 parts active compound

95 parts talc 2% dust 2 parts active compound

1 part highly dispersed silicic acid 97 parts talc These dusts are formed by mixing the components then gπnding the mixture to the desired particle size

Wettable powders 70% 70 parts active compound 5 parts sodium dibutylnaphthylsulfonate

3 parts naphthalenesulfonic acid/phenolsuifonic acid/phenol-sulfonic acid/formaldehyde condensate

(3 2 1)

10 parts kaolin

12 parts Champagne chalk

40% 40 parts active compound

5 parts sodium ligrun sulfonate

1 part sodium dibutylnaphthalene sulfonic acid 54 parts silicic acid

25% 25 parts active compound

4 5 parts calcium lignin sulfate

1 9 parts Champagne chalk/-hydroxyethyl cellulose (1 1)

8 3 parts sodium aluminum silicate

16 5 parts kieselguhr

46 parts kaolin

10% 10 parts active compound

3 parts of a mixture of sodium salts of saturated fatty alcohol sulfates 5 parts naphthalenesulfonic acid/formaldehyde condensate 82 parts kaolin

These wettable powders are prepared by intimately mixing the active compounds with the additives in suitable mixers, and grinding the resulting mixture in mills or rollers.

Emulsifiable concentrate:

25% 25 parts active substance

2.5 parts epoxidized vegetable oil

10 parts of an alkyiarylsulfonate/fatty alcohol polyglycol ether mixture

57.5 parts xyiene

The amount of the present compositions which constitute a herbicidally effective amount depends upon the nature of the seeds or plants to be controlled. The rate of application of active ingredients varies from about 0.01 to about 28 kilograms per hectare, preferably about 0.02 to about 1 1 kilograms per hectare with the actual amount depending on the overall costs and the desired results. It will be readily apparent to one skilled in the art that compositions exhibiting lower herbicidal activity will require a higher dosage than more active compounds for the same degree of control.

EXAMPLES

The following examples are intended to further illustrate the present invention and are not intended to limit the scope of this invention in any manner whatsoever.

Example 1

N-[4-MethyI-2-[l-methyl-3-(trinuoromethyl)-lH-pyrazol-5-yl]oxyphenyl]- cyclopropane carboxamide Compound I

A. Preparation of 5-hydroxy-l-methyl-3-trifluoromethylpyrazoIe

A. Methyl hydrazine (13.3 ml, 1 1.5 g, 0.25 mol) was added dropwise to a chilled (ice- bath) solution of ethyl 4,4,4-trifluoroacetoacetate (46.0 g, 0.25 mol) in toluene (250 ml) at such a rate that the temperature of the reaction could be maintained below 10°C (ice-bath cooling). Once the addition was complete the ice-bath was removed and strirring continued at room temperature for 1 hour and then at reflux (Dean-Stark) for 3 h. The mixture was allowed to cool to room temperature and allowed to stand over 3 days. The precipitate was collected by filtration and washed with hexane to give 5-hydroxy-l-methyl-3- trifluoromethylpyrazole (30.7 g) as a colorless solid, m.p. 170-173 °C.

B. Preparation of 5-Methyl-Hl-methyl-3-(trifluoromethyl)-lH-pyrazo.-5-yl]oxy-2- nitrobenzene

5-Hydroxy-l-methyl-3-trifluoromethylpyτazole (8.30 g, 50 mmol) and powdered potassium carbonate (8.29 g, 60 mmol) were stirred together in dimethylsulfoxide (40 ml) for 30 minutes. 3-Fluoro-4-nitrotoluene (7.76 g, 50 mmol) was added and the mixture heated at

70 °C for 17 h, then cooled to room temperature. The mixture was partitioned between diethyl ether and water, the ethereal extract washed with water and brine, dried over magnesium sulfate, filtered and the filtrate evaporated. The residue was further purified by flash column chromatography over silica gel, and the desired fraction collected and triturated with hexane to give the desired product as a pale yellow solid (6.20 g), m.p 88-

90 °C

C. Preparation of 2-Amino-5-methyl-l-[l-methyl-3-(trifluoromethyi)-lH-pyrazoI-5- yl]oxyphenyl]oxybenzene

5% Palladium on charcoal (0.2 g) was added to a solution of the compound prepared in B above (2.00 g , 6.6 mmol) in ethanol (50 ml) and the mixture shaken in a Parr hydrogenator at 50 p.s.i. for 2 h. The catalyst was removed by filtration and the filtrate evaporated in vacuo The residue was further purified by flash column chromatography over silica gel, and the desired amine obtained as a pale pink oil (1.73 g).

D. Preparation of N-[4-IVIethyl-2-|l-methyl-3-(triπuoromethyl)-lH-pyrazol-5- yl]oxyphenyl]cyciopropane carboxamide

Cyclopropylcarbamyl chloride (0.22 ml, 0.25 g, 2.4 mmol) was added to a mixture of triethylamine (0.50 ml 0.36 g, 3.6 mmol) and the amine prepared in C above (0.66 g, 2.4 mmol) in dichloromethane (10 ml) and the mixture stirred at room temperature for 23 h The mixture was partitioned between diethyl ether and water, the ethereal extract washed with water and brine, dried over magnesium sulfate, filtered and the filtrate evaporated Trituration with hexane gave Compound 1 (0.56 g) as a colorless solid, m.p. 126 -128°C Example 2

Starting from the amine prepared in Example 1 C, Compounds 2-5 were prepared by similar processes using appropπate starting materials

Example 3

Preparation of Isopropyl N-[4,5-dichloro-2-[l-methyl-3-(trifluoromethyl)-lH-pyrazol- 5-yi]oxybenzenecarbamate Compound 18

A. Preparation of 4,5-Dichloro-l-[l-methyl-3-(trifluoromethyl)-lH-pyrazol-5-yl]oxy- 2-nitrobenzene

5-Hydroxy-l-methyl-3-trifluoromethylpyrazole (7 0 g, 40 mmol) and powdered potassium carbonate (1 1 4 g, 80 mmol) were stirred together in dimethylsulfoxide (40 ml) for 30 minutes 4,5-Dichloro-2-fluoronιtrobenzene (7 9 g, 50 mmol) was added and the mixture stirred at room temperature for 18 h The mixture was partitioned between diethyl ether and water, the ethereal extract washed with water and brine, dried over magnesium sulfate, filtered and the filtrate evaporated The residue was further purified by flash column chromatography over silica gel, to give the desired product (5.9 g) as a iight yellow solid, m p 99-100 °C

B. Preparation of 2-Amino-4,5-dichloro-2-[l-methyl-3-(trifluoromethyl)-lH-pyrazol- 5-yl}oxybenzene

Raney Nickel (ca 0 5 g) was added to a solution of the compound prepared in A above

(5 5 g , 16 mmol) in ethanol (100 ml) and the mixture shaken in a Parr hydrogenator at 50 p s i for 2 h The catalyst was removed by filtration and the filtrate evaporated in vacuo to give the desired product as a pale solid (4 7 g), m p 126 - 128°C

C. Preparation of Isopropyl N-[4,5-dichloro-2-[l-methyl-3-(trifluoromethyl)-lH- pyrazol-5-yl]oxybenzenecarbamate

The amine prepared in B above ( 1.0 g, 3 mmol) was added to a chilled (ice-bath) mixture of isopropyichloroformate (1 M solution in toluene, 7 ml, 7 mmol) and triethylamine (0 6 g, mmol) and the mixture stirred for 18 h The mixture was partitioned between diethyl ether and water, the ethereal extract washed with water and brine, dried over magnesium sulfate, filtered and the filtrate evaporated The residue was further purified by flash column chromatography over silica gel, to give the desired product (0 2 g) as a colorless solid, m p 125-126 °C

Example 4

N-[4-Methoxy-2-[l-methyl-3(trifluoromethyl)-lH-pyrazol-5-ylJoxyphenyl] cyclopropanecarboxamide Compound 20

A. Preparation of 5-FIuoro-l-[2-methyl-3(trifluoromethyl)-lH-pyrazoI-5-yl]oxy-2- nitrobenzene

5-Hydroxy-l-methyl-3-trifluoromethylpyrazole (8 3 g, 50 mmol) and powdered potassium carbonate (8 3 g, 60 mmol) were stirred together in dimethylsulfoxide (40 ml) for 30 minutes 2,4-Difluoronιtrobenzene (7 9 g, 50 mmol) was added and the mixture stirred at room temperature for 18 h The mixture was partitioned between diethyl ether and water, the ethereal extract washed with water and bπne, dπed over magnesium sulfate, filtered and the filtrate evaporated The residue was further puπfied by flash column chromatography over silica gel, to give the desired product (2 3 g) as a solid m p 68-70 °C

B. Preparation of 5-Methoxy-l-Il-methyl-3(trifluoromethyl)-lH-pyrazol-5-yl]oxy-2- nitro benzene

The compound prepared in A above ( 1 5 g, 5 mmol) was dissolved in methanol (20 ml) and sodium methoxide (25% solution in methanol, 1 1 ml, 5 mmol) added The mixture was stirred at room temperature for 3 h, then partitioned between diethyl ether and water The ethereal extract was washed with water and bnne, dπed over magnesium sulfate, filtered and the filtrate evaporated The residue was tnturated with hexane to give the desired product (0 8 g) as a yellow solid

C. Preparation of 2-Amιno-5-methoxy- 1-[ l-methyl-3(trifluoromethyl)-lH-pyrazol-5- yl]oxy benzene

Raney Nickel (ca 0 08g) was added to a solution of the compound prepared in B above (0 8 g , 2 5 mmol) in methanol (50 ml) and the mixture shaken m a Parr hydrogenator at 50

19

SUBSTTI UTE SHEET (RULE 26) p s l for 1 h The catalyst was removed by filtration and the filtrate evaporated in vacuo The product was used without further punfication in D below

D. Preparation of N-{4-Methoxy-2-[l-methyl-3(trifluoromethyl)-lH-pyrazol-5- yljoxyphenyl] cyclopropanecarboxamide

Cyclopropyicarbamyl chloπde (0.2 g, 1 4 mmol) was added to a mixture of triethylamine (0 3 g, 2 8 mmol) and the amine prepared in C above (0 4 g, 1 4 mmol) in dichloromethane (10 ml) and the mixture stirred at room temperature for 30 minutes The mixture was partitioned between diethyl ether and water, the ethereal extract washed with water and brine, dπed over magnesium sulfate, filtered and the filtrate evaporated Trituration with hexane gave Compound 20 (0 4 g) as a colorless solid, m p 140-142 °C

Example 5

N-{4-Methyl-2-[l-methyl-3-(trifluoromethyl)-lH-pyrazol-5-yl]thiophenyl]- cyclopropane carboxamide Compound 142

A. Preparation of 5-thio-l-methy.-3-trifluoromethylpyrazole

A 5-hydroxy-l-methyl-3-tnfluorornethylpyrazole (30 g, 180 mmol) (Example 1, Part A) was dissolved in toluene (250 mL) Lawesson's reagent (36 5 g, 90 mmol) was added and the mixture was heated to reflux for 8 hours An additional 10 0 g (20 mmol) of Lawesson's reagent was added and the mixture continued at reflux for 2 hours The mixture was allowed to cool, stirπng at room temperature for 18 hours The solution was poured into saturated aqueous sodium carbonate solution and partitioned The resulting aqueous phase was acidified to pH 2 with concentrated hydrochlonc acid The mixture was extracted with diethyl ether, dned over magnesium sulfate, filtered and the filtrate evaporated to give the desired product as a yellow oil (26 g)

B. Preparation of 5-Methyl-l-[l-methyl-3-(trifluoromethyl)-lH-pyrazol-5-yl)thio-2- nitrobenzene

B The thiol prepared in step A above, (5 g, 17 mmol) was dissolved in 4-methyl-2- pentanone (50 mL) To this was added 3-fluoro-4-nιtrotoluene (2 6 g, 17 mmol) and the mixture was stined for 5 min Potassium carbonate (3 2 g, 22 mmol) was added and the mixture was heated to reflux for 2 hours The heat was removed and the mixture was cooled to room temperature The mixture was poured into water and this was neutralized with acetic acid The resulting mixture was partitioned between diethyl ether and water, the ethereal extract was washed with water, dried over magnesium sulfate, filtered and the filtrate evaporated. Trituration with hexane gave the desired compound (2.0 g) as a yellow solid, m.p. 98-100 °C

C. Preparation of 2-Amino-5-methyl-l-[l-methyI-3-(trifluoromethyl)-lH-pyrazol-5- yl]thiobenzene

C. The nitrotoluene prepared above (1.8 g, 5.7 mmol) was added to methanol (50 mL)

Palladium on carbon (0.1 g, 5%) was added and the mixture was hydrogenated at 50 p.s.i. for 3 hours. The catalyst was removed by filtration and the filtrate evaporated. The resulting residue was triturated with hexane to give the desired product as a yellow solid (0 8 g) m.p 64-68° C

D. Preparation of N-[4-Methyl-2-[l-methyl-3-(trifluoromethyl)-lH-pyrazol-5- yl]thiophenyi]cyciopropane carboxamide

D Cyclopropanecarbonyl chloride (0 3 g, 3 mmol) and triethylamine (0.5g, 4.5 mmol) were added dropwise to a chilled (ice-bath) solution of the aniline prepared in Step C above (0.7 g, 2 4 mmol) in dichloromethane (20 mL). The reaction was stirred at room temperature for 24 hours, then partitioned between diethyl ether and water. The ethereal extract was dried over magnesium sulfate, filtered and the filtrate evaporated. Trituration with hexane gave Compound 142 (0.55 g) as a yellow solid, m.p. 162-164° C.

Example β

Preparation of Isopropyl N-[4,5-dichloro-2-[l-πιethyl-3-(trifluoromethy.)-lH- pyrazol-5-yl]thiobenzenecarbamate Compound 143

Triphosgene (0 6 g, 2 mmol) was added to a solution of the aniline prepared in Step C in

Example 5 above ( 1.25 g, 4 mmol) in ethyl acetate (20 mL) and the mixture was heated at reflux for 1 hour The mixture was cooled to room temperature and the solvent removed by rotary evaporation. The residue was dissolved in isopropanol (20mL) and stirred at room temperature for 1 hour, then the solvent was evaporated. Trituration with hexane gave

Compound 2 (1 0 g) as a colorless solid, m.p. 1 18-120 °C TABLE I

4 CH₃ CF₃ H CH(CH₃)₂ 5 CH₃ CF₃ H CH₂CH₃ 6 CH₃ CF₃ H CH(CH₃)₂ 7 CH₃ CF₃ H C₂H₅ 8 CH₃ CF₃ H cyclopropyl 9 CH₃ CF₃ H CH(CH₃)₂

Comp. No. R' R² R³ R⁴ R⁵ R⁶ R⁷ R⁸

27 CH₃ CF₃ H CH(CH₃)CH₂CH₃ H H CH₃ H

28 CH₃ CF₃ H CH(CH₃)₂ H H CH₃ H

29 CH₃ CF₃ H CH₂C(CH₃)₃ H H CH₃ H

30 CH₃ CF₃ H CH₂CH(CH₃)₂ H H CH₃ H O r 31 CH₃ C F₅ H C₂H₅ H H CH₃ H O

32 CH₃ C₂F₅ H cyclopropyl H H CH₃ H

33 CH₃ CF₃ H CH(CH₃)₂ H H OCH₃ H O

34 CH₃ CF₃ H CH(CH₃)₂ H H OCH₃ H s 35 CH₃ cyclopropyl H cyclopropyl H H CH₃ H z 36 CH isopropyl H C₂H₅ H H CH₃ H g 37 CH₃ cyclopropyl H CH(CH₃)₂ H H CH₃ H

38 CH₃ cyclopropyl H CH(CH₃)₂ H H CH₃ H

39 CH₃ CF₃ H cyclopropyl CH₃ H CH₃ H

40 CH₃ CF₃ H cyclopropyl CH₃OCH₂ H CH₃ H

41 CH₃ CF₃ Br cyclopropyl H H CH₃ H

42 CH₃ CF₃ H C₂H₅ H H OCH₃ H

43 CH₃ CF₃ H C₂H₅ H H OCH₃ H

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HERBICIDAL SCREENING TESTS

The compounds listed in the foregoing table were tested for herbicidal activity by various methods and at various rates of application. The results of some of these tests are given below Results obtained in herbicidal screening are affected by a number of factors including: the amount of sunlight, soil type, soil pH, temperature, humidity, depth of planting, plant growth stage, application rate as well as many other factors. All testing procedures are administered with the least amount of variability possible. State of the art equipment and techniques are employed to enable the screening process to remain consistent and reliable

PRE-EMERGENCE HERBICIDAL SCREENING TEST

On the day preceding treatment, seeds of several different weed species were planted in sandy loam soil containing only trace organic matter. Propagules were sown in individual rows using one species per row across the width of an aluminum flat. Seeding depths ranged from 1.0 to 1 5 cm and plant densities ranged from 3 to 25 plants per row depending on individual plant species.

The grass weeds planted (Table II) were broadleaf signalgrass (Brachiarta platyphylla) "BRAPP", large crabgrass (Digttana sangiitnalts) "DIGSA", bamyardgrass (Echtnochloa crusga/li) "ECHCG", rigid ryegrass (Loliu rigtdum) "LOLRI"; fall panicum (Panicum dtchotomiβorum) "PANDI"; giant foxtail (Setart fahert) "SETFA", green foxtail (Setana vtndis) "SETVI"; blac grass (Alopecurus myosurotdes) "ALOMY", wild oat (Avena fatita) "AVEFA" and Johnsongrass (Sorghum halepense) "SORHA"

The broadleaf weeds planted (Table III) were velvetleaf (Abutilon theophrastt) "ABUTH", redroot pigweed (Amaranihus retroflexus) "AMARE", common lambsquarters (Chenopodium album) "CHEA ", ivyieaf morningglory (Ipomoea hederacea) "IPOHE", common purslane {Portulaca oleracea) "POROL", common cockleburr (Xanthium strumartum) "XANST", and catchweed bedstraw (Galtum aparine) "GALAP" Additionally, yellow nutsedge (Cyperus esculentus) "CYPES" nutlets were also sown. Solutions of the test compounds were prepared by weighing out an appropπate amount of the test compound to provide an application rate of 0 25 kilograms per hectare ( kg/ha), then dissolving the compound in a 50 50 mixture of deionized water and acetone containing 0 5% v/v Tween 20^® (polyoxyethylene sorbitan monolaurate emulsifier) as a surfactant Additional solvents, not exceeding 15% of spray volume, were used if needed to dissolve the compound

The soil surface was sprayed inside an enclosed linear spray table with the nozzle set above the soil line The spray table was calibrated to deliver 400 L/ha with the application rate being 0 25 kg/ha After treatment, the flats were placed into a greenhouse and watered as needed The greenhouse environmental systems provided the plants with natural and artificial lighting to attain 14 hours of light per day Day and night temperatures were maintained at 29° and 21°C, respectively

The degree of weed control was evaluated and recorded 17-21 days after treatment as a percentage of weed control as compared to the growth of the same species of the same age in an untreated control flat Percent control is the total injury to the plants due to all factors including inhibited emergence, stunting, malformation, chlorosis and other types of plant injury The results of the pre-emergence screening tests are shown in Tables II and III below The control ratings range from 0 to 100 percent, where 0 represents no effect with growth equal to the untreated control and where 100 represents complete kill The symbol "--" indicates that no test was performed at the 0 25 kg/ ha level of application

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POST-EMERGENCE HERBICIDAL SCREENING TEST

The soil was prepared with the same methodology described for the pre- emergence test The following species were used.

The grass weeds planted were "BRAPP", "ECHCG", "LOLRI", "PANDI", "SETFA", "SETVI", "ALOMY", "AVEFA" and "SORHA"

The broadleaf weeds planted were "ABUTH", "AMARE"; "CHEAL", "IPOHE", "POROL", "XANST", "GALAP" and scentless chamomile (Matricarta perforata) "MATIN" Additionally, "CYPES" nutlets were also sown

Post-emergence flats were placed in the greenhouse under the same environmental conditions as described for the pre-emergence flats and watered as needed Plants were grown for 10 to 12 days (or to the appropriate growth stage) pπor to compound application Grasses were sprayed at a 3 to 4 leaf stage and broadleaves at a 1 to 2 leaf stage Yellow nutsedge was 5 to 7 cm tall at application

Plants were sprayed 30 5 cm (12 inches) above the foliage with the same spray solution as prepared for the pre-emergence test The application rate was 0.25 kg ha Treated plants were then returned to a greenhouse and watered daily without wetting the foliage The degree of weed control was evaluated 17-21 days after application and recorded as percentage of control as compared to the growth of the same species in an untreated control flat of the same age The percent control scale (0-100%) used to evaluate the pre-emergence treatment was also applied to the post-emergence treatment The post-emergence screening test results are shown in Table IV (grass weeds) and Table V (broadleaf weeds) below

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TABLE V - POST-EMERGENCE SCREENING

COMP. NO. ABUTH AMARE CHEAL IPOHE POROL XANST GALAP MATIN CYPES

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POST FLOODING POST EMERGENCE HERBICIDAL SCREENING TEST

Seeds of three weeds species were seeded into 8 9 X 8 9 cm pots. The pots were previously filled with clay soil which contained 2.2% organic matter and had a pH of 5 7 The weed species were Echtnochloa crus-gallt ("ECHCG"), Cyperus serottnus ("CYPDI"), and Sagittarta pygmaea ("SAGPY"). In addition, the rice hybrid "Kosihikara" (Oryza sattva) was also seeded.

The pots were placed into a 10 liter plastic tubs, lined with a plastic bag. At an early growth stage, the rice plants were transplanted into an 8 9 cm X 8.9 cm pot, 3 plants per pot at a depth of 2 cm The pots were placed into the tubs with the weed species The tubs were flooded with water to a depth of 2-3 cm

At a middle growth stage the tubs were injected with the test material in acetone at a rate of 0 25 kg per hectare The degree of weed control was evaluated and recorded 22 days after treatment as a percentage of weed control as compared to the growth of the same species of the same age in an untreated control flat. Percent control is the total injury to the plants due to all factors including: inhibited emergence, stunting, malformation, albinism, chlorosis and other types of plant injury. The control ratings range from 0 to 100 percent, where 0 represents no effect with growth equal to the untreated control and where 100 represents complete kill The symbol "— " indicates that no test was performed at the 0 25 kg/ha level of application. Representative results of the inventive compounds are shown in Table VI

66

SUBSTTI UTE SHEET (RULE 26) Although the invention has been descπbed with reference to preferred embodiments and examples thereof, the scope of the present invention is not limited only to those described embodiments. As will be apparent to persons skilled in the art, modifications and adaptations to the above-described invention can be made without departing from the spirit and scope of the invention, which is defined and circumscribed by the appended claims

Claims

WHAT IS CLAIMED IS:

1. A compound of formula (I),

wherein:

R¹ is optionally substituted C₁-C₆ alkyl or C₁-C₆ haloalkyl;

R² is optionally substituted C₁-C₆ alkyl, C₁-C₆ haloalkyl or C₃-C₆ cycloalkyl;

R³ is hydrogen, halogen, C₁-C₆ alkyl or C₁-C₆ haloalkyl;

R⁴ is optionally substituted C₁-C₆ alkyl, C₁-C₆ haloalkyl, optionally substituted C₁-C₆ alkoxy, optionally substituted C₃-C₆ cycloalkyl, optionally substituted (C₁-C₆) alkoxy(C₁-C₆ )alkyl, optionally substituted C₂-C₆ alkenyl, optionally substituted C₂-C₆ alkynyl, optionally substituted aryl, optionally substituted heteroaryl, or an optionally substituted five or six membered heterocyclic ring containing one or more heteroatoms selected from O, N or S;

R⁵ is hydrogen, optionally substituted C₁-C₆ alkyl or (C₁-C₆)alkoxy-(C₁-C₆)alkyl;

R⁶, R⁷, R⁸ and R⁹ arc independently selected from hydrogen, halogen, optionally substituted C₁-C₆ alkyl, optionally substituted C₂-C₆ alkenyl, optionally substituted C₂-C₆ alkynyl, optionally substituted C₁-C₆ alkoxy, (C₁-C₆)alkoxy-(C₁-C₆)alkyl, C₁-C₆ haloalkyl, C₁-C₆ haloalkoxy, cyano, nitro, -S(O)_p-R¹⁰ wherein p is 0, 1 or 2 and R¹⁰ is C₁-C₃ alkyl or C₁-C₃ haloalkyl, -OSO₂R¹¹ wherein R¹¹ is C₁-C₃ alkyl, -CO₂H, -COR¹²,

-COOR¹² or -NHCOR¹² wherein R¹² is C₁-C₆ alkyl, C₁-C₆ haloalkyl, optionally substituted C₃-C₆ cycloalkyl, optionally substituted aryl, optionally substituted heteroaryl, (C₁-C₆)alkoxy-(C₁-C₆)alkyl or C₁-C₆ alkylthio, -CONR¹³R¹⁴ or -NR¹³R¹⁴ wherein R¹³ and R¹⁴ may be the same or different and are each hydrogen, C₁-C₆ alkyl, C₁-C₆ haloalkyl, optionally substituted C₃-C₆ cycloalkyl, optionally substituted C₂-C₆ alkenyl, optionally substituted C₂-C₆ alkynyl, optionally substituted aryl, optionally substituted heteroaryl, (C₁-C₆)alkoxy-(C₁-C₆) alkyl or C₁-C₆ alkylthio, or R¹³ and R¹⁴ together with the N to which they are bound may form a ring having 3-8 members, one or more of which may be O, S or N; and

A is O, S, SO or SO₂;

Y is O or S;

X is a carbon-carbon single bond, S, C=O or C=N; or an agriculturally acceptable salt thereof.

2. A compound according to Claim 1, wherein R¹ is C₁-C₃ alkyl or C₁-C₃ haloalkyl; R² is C₁-C₃ alkyl or C₁-C₃ haloalkyl; R³ is hydrogen; and R⁵ is hydrogen.

3. A compound according to Claim 1, wherein R¹ is methyl; R² is

trifluoromethyl; R³ is hydrogen; R⁴ is selected from the group consisting of cyclopropyl, isopropyl and ethyl; R⁵ is hydrogen; R⁶ is hydrogen; R⁷ is methyl; R⁸ is hydrogen; R⁹ is hydrogen and X is a carbon-carbon single bond.

4. A compound according to Claim 1, wherein R¹ is methyl; R² is

trifluoromethyl; R³ is hydrogen; R⁴ is cyclopropyl; R⁵ is hydrogen; R⁶ is hydrogen; R⁷ is chloro; R⁸ is hydrogen; R⁹ is hydrogen and X is a carbon-carbon single bond.

5. A compound according to Claim 1, wherein R¹ is methyl; R² is

trifluoromethyl; R³ is hydrogen; R⁴ is isopropenyl; R⁵ is hydrogen; R⁶ is hydrogen; R⁸ is hydrogen; R⁹ is hydrogen and X is a carbon-carbon single bond.

6. An herbicidal composition comprising an herbicidally effective amount of a compound according to formula (la),

wherein:

R¹ is optionally substituted C₁-C₆ alkyl or C₁-C₆ haloalkyl;

R is optionally substituted C₁-C₆ alkyl, C₁-C₆ haloalkyl or C₃-C₆ cycloalkyl;

R³ is hydrogen, halogen, C₁-C₆ alkyl or C₁-C₆ haloalkyl;

R⁴ is optionally substituted C₁-C₆ alkyl, C₁-C₆ haloalkyl, optionally substituted C₁-C₆ alkoxy, optionally substituted C₃-C₆ cycloalkyl, optionally substituted (C₁-C₆) alkoxy(C₁-C₆ )alkyl, optionally substituted C₂-C₆ alkenyl, optionally substituted C₂-C₆ alkynyl, optionally substituted aryl, optionally substituted heteroaryl, or an optionally substituted five or six membered heterocyclic ring containing one or more heteroatoms selected from O, N or S;

R⁵ is hydrogen, optionally substituted C₁-C₆ alkyl or (C₁-C₆)alkoxy-(C₁-C₆)alkyl;

R⁶, R⁷, R⁸ and R⁹ are independently selected from hydrogen, halogen, optionally substituted C₁-C₆ alkyl, optionally substituted C₂-C₆ alkenyl, optionally substituted C₂-C₆ alkynyl, optionally substituted C₁-C₆ alkoxy, (C₁-C₆)alkoxy-(C₁-C₆)alkyl, C₁-C₆ haloalkyl, C₁-C₆ haloalkoxy, cyano, nitro, -S(O)_p-R¹⁰ wherein p is 0, 1 or 2 and R¹⁰ is C₁-C₃ alkyl or C₁-C₃ haloalkyl, -OSO₂R¹¹ wherein R¹¹ is C₁-C₃ alkyl, -CO₂H, -COR¹²,

-COOR¹² or -NHCOR¹² wherein R¹² is C₁-C₆ alkyl, C₁-C₆ haloalkyl, optionally substituted C₃-C₆ cycloalkyl, optionally substituted aryl, optionally substituted heteroaryl, (C₁-C₆)alkoxy-(C₁-C₆)alkyl or C₁-C₆ alkylthio, -CONR ¹³R¹⁴ or -NR¹³R¹⁴ wherein R¹³ and R¹⁴ may be the same or different and are each hydrogen, C₁-C₆ alkyl, C₁-C₆ haloalkyl, optionally substituted C₃-C₆ cycloalkyl, optionally substituted C₂-C₆ alkenyl, optionally substituted C₂-C₆ alkynyl, optionally substituted aryl, optionally substituted heteroaryl, (C₁-C₆)alkoxy-(C₁-C₆)alkyl or C₁-C₆ alkylthio, or R¹³ and R¹⁴ together with the N to which they are bound may form a ring having 3-8 members, one or more of which may be O, S or N; and

A is O, S, SO or SO₂;

Y is O or S;

X is a carbon-carbon single bond, O, S, C=O or C=N; or an agriculturally acceptable salt thereof; and a carrier therefor.

7. An herbicidal composition according to Claim 6, wherein R¹ is C₁-C₃ alkyl or C₁-C₃ haloalkyl; R² is C₁-C₃ alkyl or C₁-C₃ haloalkyl; R³ is hydrogen; and R⁵ is hydrogen.

8. An herbicidal composition according to Claim 6, wherein R¹ is methyl; R² is trifluoromethyl; R³ is hydrogen; R⁴ is selected from the group consisting of cyclopropyl isopropyl and ethyl; R⁵ is hydrogen; R⁶ is hydrogen; R⁷ is methyl; R⁸ is hydrogen; R⁹ is hydrogen and Z is a carbon-carbon single bond or oxygen.

9. A method for controlling undesirable vegetation comprising applying to an area where control is desired an herbicidally effective amount of a compound of formula (Ia),

wherein:

R¹ is optionally substituted C₁-C₆ alkyl or C₁-C₆ haloalkyl;

R² is optionally substituted C₁-C₆ alkyl, C₁-C₆ haloalkyl or C₃-C₆ cycloalkyl;

R³ is hydrogen, halogen, C₁-C₆ alkyl or C₁-C₆ haloalkyl;

R⁴ is optionally substituted C₁-C₆ alkyl, C₁-C₆ haloalkyl, optionally substituted C₁-C₆ alkoxy, optionally substituted C₃-C₆ cycloalkyl, optionally substituted (C₁-C₅) alkoxy(C₁-C₆ )alkyl, optionally substituted C₂-C₆ alkenyl, optionally substituted C₂-C₆ alkynyl, optionally substituted aryl, optionally substituted heteroaryl, or an optionally substimted five or six membered heterocyclic ring containing one or more heteroatoms selected from O, N or S;

R⁵ is hydrogen, optionally substituted C₁-C₆ alkyl or (C₁-C₆)alkoxy-(C₁-C₆)alkyl;

R⁶, R⁷, R⁸ and R⁹ are independently selected from hydrogen, halogen, optionally substimted C₁-C₆ alkyl, optionally substimted C₂-C₆ alkenyl, optionally substimted C₂-C₆ alkynyl, optionally substituted C₁-C₆ alkoxy, (C₁-C₆)alkoxy-(C₁-C₆)alkyl C₁-C₆ haloalkyl, C₁-C₆ haloalkoxy, cyano, nitro, -S(O)p-R¹⁰ wherein p is 0, 1 or 2 and R¹⁰ is C₁-C₃ alkyl or C₁-C₃ haloalkyl, -OSO₂R¹¹ wherein R¹¹ is C₁-C₃ alkyl, -CO₂H, -COR¹²,

-COOR¹² or -NHCOR¹² wherein R¹² is C₁-C₆ alkyL C₁-C₆ haloalkyl, optionally substimted C₃-C₆ cycloalkyl, optionally substituted aryl, optionally substituted heteroaryl, (C₁-C₆)alkoxy-(C₁-C₆)alkyl or C₁-C₆ alkylthio, -CONR¹³R¹⁴ or -NR¹³R¹⁴ wherein R¹³ and R¹⁴ may be the same or different and are each hydrogen, C₁-C₆ alkyl, C₁-C₆ haloalkyl, optionally substimted C₃-C₆ cycloalkyl, optionally substituted C₂-C₆ alkenyl, optionally substituted C₂-C₆ alkynyl, optionally substimted aryl, optionally substimted heteroaryl, (C₁-C₆)alkoxy-(C₁-C₆)alkyl or C₁-C₆ alkylthio, or R¹³ and R¹⁴ together with the N to which they are bound may form a ring having 3-8 members, one or more of which may be O, S or N; and

A is O, S, SO or SO₂;

Y is O or S;

Z is a carbon-carbon single bond, O, S, C=O or C=N; or an agriculturally acceptable salt thereof.

10. A method for controlling undesirable vegetation according to Claim 9, wherein: R¹ is C₁-C₃ alkyl or C₁-C₃ haloalkyl; R² is C₁-C₃ alkyl or C₁-C₃ haloalkyl; R³ is hydrogen; and R⁵ is hydrogen.