WO1993024468A1

WO1993024468A1 - Pyrimidinyl- and triazinyl- salicyl- and picolylamides and the use, as herbicides, and preparation thereof

Info

Publication number: WO1993024468A1
Application number: PCT/EP1993/001264
Authority: WO
Inventors: Christoph Lüthy; Raymond Fisher
Original assignee: Ciba-Geigy Ag
Priority date: 1992-06-02
Filing date: 1993-05-21
Publication date: 1993-12-09
Also published as: ZA933815B; MX9303255A; IL105873A0; AU4314693A

Abstract

N-pyrimidinyl- and N-triazinyl-salicyl- and picolyl-amide derivatives of formula (I), the meanings of the substituents being given in claim 1, and the salts of compounds of formula (I), exhibit herbicidal and plant-growth-regulating action. They are suitable as active ingredients in compositions for controlling weeds and in compositions for influencing the growth of useful plants in a positive manner.

Description

PYRIMIDINYL- AND TRIAZINYL- SALICYL- AND PICOLYLAMIDES AND THE USE, AS HERBI¬ CIDES, AND PREPARATION THEREOF

The present invention relates to novel herbicidally active and plant-growth-regulating N-pyrimidinyl- and N-triazinyl-salicyl- and -picolyl-amide derivatives, especially N-pyrimidinyl- and triazinyl-salicyl- and -picolyl-α-hydrazides and N-pyrimidinyl- and triazinyl-salicyl- and -picolyl-hydroxamic acid esters, to processes for the preparation thereof, to compositions that comprise them as active ingredients, and to the use thereof in the control of weeds, especially in the selective control of weeds in crops of useful plants or in the regulation and inhibition of plant growth.

2-phenoxy-pyrimidines and -triazines having herbicidal action are generally known. Such compounds are disclosed, for example, in GB-A-2 237 570 and EP-A-0469711. Novel N-pyrimidinyl- and N-triazinyl-salicyl- and -picolyl-amide derivatives having herbicidal properties have now been found.

The N-pyrimidinyl- and N-triazinyl-salicyl- and -picolyl-amide derivatives according to the invention correspond to formula I

wherein

A is hydrogen or a group

X is nitrogen or C-R ;

Y is nitrogen or, if Z is nitrogen, also is methine, or methine substituted by fluorine or by chlorine;

Z is methine, methine substituted by fluorine, chlorine or by methyl, or is nitrogen;

R₂ is C^alkyl, C₂-₃alkynyl, cyclopropyl, chloromethyl, difluoromethyl, trifluoro- methyl, methoxy, ethoxy, difluoromethoxy, C^alkylamino, dimethylamino, diethylamino or methoxymethylamino;

R₂ is hydrogen, methyl, fluorine, chlorine, C^alkoxy, difluoromethoxy, trifluoro- ethoxy, methylthio or ethylthio;

R₃ is hydrogen, fluorine, chlorine, methyl, methoxy or, together with R₄, -CH=CH-CH=CH- or -CH=CH-CH=N-;

R₄ is hydrogen, fluorine, chlorine, bromine, iodine,

trifluoromethyl, vinyl,

2-propenyloxy, 2-propynyloxy, difluoromethoxy, benzyloxy, phenoxy, phenylthio, phenyl, thienyl, pyrazolyl, imidazolyl or triazolyl; or phenoxy, phenyl- thio, phenyl, thienyl, pyrazolyl, imidazolyl or triazolyl each of which is mono- or di-substituted by fluorine, chlorine, bromine, methyl or by methoxy;

R₅ is hydrogen or C^alkyl;

R₆ is hydrogen or

that may be unsubstituted or mono- or poly-substituted by fluorine or mono-substituted by chlorine, bromine, hydroxy, ^alkoxy, carboxy, C^alkoxycarbonyl, cyano, vinyl, ethynyl or by phenyl, it being possible for the phenyl group for its part to be mono- or poly-substituted by fluorine, chlorine, bromine, methyl, ethyl, trifluoromethyl, methoxy, carboxy, C^alkoxycarbonyl or by nitro; phenyl, naphthyl, or phenyl or naphthyl each of which is mono- or poly-substituted by fluorine, chlorine, bromine, iodine, Ci

difluoromethoxy, cyano, nitro or by C_Malkoxycarbonyl; pyridyl, pyrazinyl, pyrimidinyl or quinolinyl; or pyridyl, pyrazinyl, pyrimidinyl or quinolinyl each of which is mono- or poly-substituted by fluorine, chlorine, methyl, methoxy or by trifluoromethyl;

C_1-4alkylcarbonyl, benzoyl, or benzoyl mono- or poly-substituted by fluorine, chlorine, bromine, methyl, ethyl, trifluoromethyl or by methoxy; Ci^alkoxycarbonyl, aminocarbonyl, aminothiocarbonyl, or aminocarbonyl or aminothiocarbonyl each of which is mono- or di-substituted by C^alkyl or mono- substitutpd by phenyl, it being possible for the phenyl group to be mono- or poly- substituted by fluorine, chlorine, methyl or by methoxy;

phenylsulfonyl, or phenylsulfonyl mono- or di-substituted by fluorine, chlorine, C₁.₃alkyl, trifluoromethyl or by methoxy; or R₅ and Rg form together with the nitrogen atom to which they are bonded a 5-, 6- or 7-membered heterocyclic ring which may for its part contain one or two nitrogen atoms, an oxygen atom, a sulfur atom or a group -S(O)-, -S(O)₂-, -C(O)-, -C(O)O-, -C(O)S- -C(S)O- or -C(S)S- and/or may additionally be mono- or poly- substituted by C^alkyl or mono-substituted by benzyl, C alkoxy, hydroxy-C^- alkyl or by C^alkoxy-Cx-^alkyl;

R₇ is hydrogen, C_1-4alkyl, C^alkylthio or, together with R₈, -CH₂CH₂CH₂CH₂~> -GH₂CH₂CH₂CH₂CH₂- or -SCH₂CH₂S-;

R₈ is C^alkyl, C₃.₆cycloalkyl, phenyl, or phenyl substituted by fluorine, chlorine, bromine, methyl, trifluoromethyl or by methoxy, or is C^alkoxy, C₁.₂alkylthio,

or cyano; and

R is hydrogen,

carbonyl-Cj ^alkyl, benzyl, phenyl, or benzyl or phenyl each of which is mono- or poly-substituted by fluorine, chlorine, bromine, methyl, trifluoromethyl, nitro or by methoxy; and the invention also includes salts of compounds of formula I.

In formula I, the alkyl radicals may be straight-chained or branched. The same applies also to the or each alkyl moiety of alkoxy-, alkoxycarbonyl- and other alkyl-containing groups.

If an asymmetric carbon atom or a nitrogen atom with a hindered rotation barrier is present in the compounds of formula I, then the result is that the compounds may occur in optically isomeric forms. Formula I accordingly also covers all possible stereoisomers, which are in the form of enantiomers, diastereoisomers or configuration isomers and mixtures thereof.

In the definitions C^alkyl and Ci ^alkyl are, for example, methyl, ethyl, n-propyl, isopropyl, n-butyl, sec-butyl, isobutyl, tert-butyl, pentyl and the isomers of pentyl and also hexyl and the isomers of hexyl. The alkyl groups present as or in the substituents contain preferably from 1 to 4 carbon atoms.

Examples of heterocyclic rings that the substituents R₅ and R₆ form together with the nitrogen atom to which they are bonded are pyrrolidine, piperazine, piperidine, hexa- methyleneamine, morpholine, thiomorpholine, <S>- and/or <R>-2-methoxymethylpyrrol- idine, N-methylpiperazine, 2-methylpiperazine, 4-(2-hydroxyethyl)-piperazine, 2-methyl- piperidine, 3-methylpiperidine, 4-methylpiperidine, 2,6-dimethylpiperidine, 2-methoxy- methylpiperidine, 3-ethylpiperidine, 4-methoxypiperidine, 2,6-dimethylmorpholine, 2- oxazolidinones, and 2-thiazolidinethiones, riiodanine and 4H-(l,3,4)-triazoles.

Suitable salts are especially alkali metal salts, such as lithium, sodium or potassium; alkaline earth metal salts, such as magnesium or calcium; or salts such as manganese, copper, zinc or iron; or salts of organic ammonium bases, such as ammonia, primary, secondary, tertiary or quaternary alkylamines, such as, for example, methylammonium, diethylammonium, triethylammonium, morpholimum, pyridinium, tetrabutylammonium; benzyltrimethylammonium; phosphonium; sulfonium or sulfoxonium.

From the scope covered by formula I, preferred compounds are those wherein:

a) Y is nitrogen; b) Z is methine or nitrogen; c) R] is methyl, dimethylamino or methoxy; d) R₂ is methyl, methoxy, ethoxy or difluoromethoxy; e) R₃ is hydrogen; and f) R₄ is hydrogen, fluorine, chlorine, bromine, methyl, trifluoromethyl or methoxy.

Of particular interest among the compounds of formula I are also those wherein A is a

group (Ql), the other substituents preferably being as defined under a) to

f).

From that group of compounds of formula I, attention is drawn very especially to those wherein

a) Z is methine; b) Rj is methoxy; c) R₂ is methoxy; d) R₄ is hydrogen, fluorine, chlorine, bromine, methyl, trifluoromethyl or methoxy; and e) A is a group

is Cι_ alkyl, phenyl, or phenyl mono- or di-substimted by fluorine, chlorine, methyl, tri¬ fluoromethyl, methoxy or by nitro; pyridyl or pyrazinyl, or pyridyl or pyrazinyl each of which is mono- or poly-substimted by fluorine, chlorine, methyl or by trifluoromethyl; or R₅ and R₆ form together with the nitrogen atom to which they are bonded a 5- or 6- membered heterocyclic ring which may for its part contain a nitrogen atom or an oxygen atom and or may additionally be mono- or di-substimted by

or mono-substituted by C^alkoxy-C^alkyl.

In a very especially preferred group of compounds of formula I

a) Y is nitrogen; b) Z is methine; c) R_! is methoxy; d) R₂ is methoxy; e) R₃ is hydrogen; f) R is hydrogen, fluorine, chlorine, bromine, methyl, trifluoromethyl or methoxy;

g) A is hydrogen or a group ° — Rg (Q3); and

h) R₉ is

benzyl, or benzyl mono- or di-substimted by fluorine, chlorine or by methyl.

There may be mentioned as especially preferred individual compounds from the scope of formula I:

N'-(2-cWorophenyl)-N-(4,6-ά^me oxy-2-pyrimidinyl)-2-hydroxy-benzamide,

N^,-(2-methylphenyl)-N-(4,6-dimethoxy-2-pyrimidinyl)-2-hydroxy-benzamide,

N'-(3-trifluoromethylphenyl)-N-(4,6-d ιethoxy-2-pyrimidinyl)-2-hydroxy-benzamide,

N'-(3-chloro-2-memylphenyl)-N-(4,6-dimethoxy-2-pyrimidinyl)-2-hydroxy-benzamide,

N'-phenyl-N^,-memyl-N-(4,6-dimethoxy-2-pyrimidinyl)-2-hydroxy-benzamide,

N'-(2-trifluorome ylphenyl)-N-(4,6^dimethoxy-2-pyrimidinyl)-2-hydroxy-benzamide,

N'-(2,3-dimethylphenyl)-N-(4,6-dimethoxy-2-pyrimidinyl)-2-hydroxy-benzamide, N'-(4-memoxyphenyl)-N-(4,6-dimethoxy-2-pyrimidinyl)-2-hydroxy-benzamide and N'-(4-cMoro-2-memylphenyl)-N-(4,6-o^methoxy-2-pyrimidinyl)-2-hydroxy-benzamide.

The compounds of formula I are prepared from the compounds of formula π either by heating the compound of formula π, wherein A, X, Y, Z, Rj, R₂ and R₃ are as defined under formula I, in a suitable diluent and/or by reacting it with a suitable base:

π

For example, compounds of formula la wherein X, Y, Z, R^ R₂ and R₃ are as defined under formula I and A is a group Ql are prepared either by heating a compound of formula Ha wherein X, Y, Z, R^ R₂ and R₃ are as defined under formula I and A is a group Ql and/or by treating it with a suitable base.

fla la

This reaction is carried out preferably in the presence of a suitable solvent or diluent. Suitable diluents are: hydrocarbons, such as, for example, n-heptane or toluene; halogen- ated hydrocarbons, such as, for example, dichloromethane, 1,2-dichloroethane or chloro- benzene; ethers, such as, for example, diethyl ether, diethoxymethane, tert-butyl methyl ether or tetrahydrofuran; ketones, such as, for example, acetone or 2-butanone; aprotic solvents, such as, for example, acetonitrile, dimethylformamide or dimethyl sulfoxide; protic solvents, such as, for example, ethanol or water; or two-phase systems, such as, for example, the mixture dichloromethane/water, toluene/water or tert-butyl methyl ether/- water. The reaction is carried out either by heating to melting point or in a temperature range of from approximately -10°C up to the boiling temperature of the diluent used. The operation is preferably carried out in a temperature range of from room temperature to approximately +110°C.

The reaction is carried out preferably in the presence of a base. Suitable bases are especially alkali metal salts or alkaline earth metal salts, such as, for example, sodium hydrogen carbonate, lithium carbonate or potassium carbonate; alkali metal hydrides or alkaline earth metal hydrides, such as, for example, sodium hydride or calcium hydride; alkyllithium compounds, such as, for example, n-butyllithium; amides of secondary amines, such as, for example, lithium diisopropylamide; tertiary amines, such as, for example, triethylamine, N,N-dimethylaniline, l,8-diazabicyclo[5.4.0]undec-7-ene, imidazole, pyridine, 2,5-dimethylpyridine or N,N-dimethylaminopyridine. These bases can be used in a catalytic amount, and also in stoichiometric amount or in excess, such as, for example, when pyridine is used as the solvent They are used preferably in stoichio¬ metric amount or in an amount up to a slight excess. The reaction temperatures can be varied within a wide range of from approximately -40°C up to the boiling temperature of the solvent used; preferably from approximately -10° to approximately +80°C.

Compounds of formula Ha are either known - see, for example, European Patent Application No.0469711 or British Published Application GB-A-2237570 - or can be prepared by reacting a compound of formula IH wherein X, Y, Z, R^ R₂ and R₃ are as defined above and Q is a leaving group, such as, for example, fluorine, chlorine, bromine, 2,4,6-triisopropylsulfonyl, imidazolyl, triazolyl, 2-thionothiazolidin-3-yl or N,N'-dicyclo- hexylisoureidyl, or an acid anhydride of formula IH',

with a hydrazine, hydrazide, carbazate, semicarbazide or thiosemicarbazide of formula IVa wherein R₅ and R₆ arc as defined above.

Ha la

This reaction is advantageously carried out in the presence of a base as acid-binding agent. Suitable bases are especially tertiary amines, such as, for example, triethylamine, N,N- dimethylaniline, l,8-diazabicyclo[5.4.0]undec-7-ene, imidazole, pyridine or 2,5-dimethyl- pyridine. They may be used in a catalytic amount, and also in stoichiometric amount or in excess; preferably in stoichiometric amount or in an amount up to a small excess. It is also possible to use as base a slight excess of the substrate of formula F/a employed.

The reaction is carried out preferably also in the presence of a suitable solvent or diluent. Suitable diluents are: hydrocarbons, such as, for example, toluene; halogenated hydro¬ carbons, such as, for example, dichloromethane, 1,2-dichloroethane or chlorobenzene; ethers, such as, for example, diethyl ether, diethoxymethane or tert-butyl methyl ether; aprotic solvents, such as, for example, acetonitrile; protic solvents, such as, for example, ethanol or water; or two-phase systems, such as, for example, a mixture of dichloro- methane/water, toluene/water or tert-butyl methyl ether/water.

The reaction temperatures can be varied within a wide range of from approximately -40°C up to the boiling temperature of the solvent used. The reaction is preferably carried out, however, at temperatures of from approximately -20° to approximately +30°C, especially at approximately from -10° to +10°. The reaction times may vary greatly, however, depending on the temperature of the reaction mixture and the auxiliary base used.

If desired, the reaction mixture can be converted directly into the compounds of formula la "in situ" at elevated temperature and/or with the addition of an excess of base as described above without isolating the compounds of formula Ha. The reaction temperatures can be varied within a wide range of from approximately -10°C up to the boiling temperature of the solvent used and are preferably from approximately 0° to approximately +80°C.

In a similar manner, it is also possible to prepare compounds of formula lb wherein X, Y, Z, R^ R₂ and R₃ are as defined under formula I and A is a group Q2 by reacting a compound of formula lib

as described above in the presence of a suitable diluent or a suitable base.

It is also possible to obtain compounds of formula lb by reacting a compound of formula la'", wherein X, Y, Z, R^ R₂ and R₃ are as defined under formula I and R₅ and R are hydrogen, with a corresponding ketone of formula VIII, an ortho ester of formula IX or CS₂ and an alkyl halide of formula X.

or la'"

CS₂ XR' X

In an analogous manner it is also possible to prepare compoimds of formula la, wherein X, Y, Z, R_1} R₂ and R₃ are as defined above, R₅ is hydrogen and Rg is aminocarbonyl, amino¬ thiocarbonyl, or aminocarbonyl or aminothiocarbonyl each of which is mono-substituted by or by unsubstituted or substituted phenyl, by treating a compound of formula la'" with a corresponding C^alkyl or phenyl isocyanate or isothiocyanate.

Compounds of formula Ic wherein X, Y, Z, R_l5 R₂ and R₃ are as defined under formula I and A is a group Q3 can be prepared by converting an acid anhydride of formula HI' or a compound of formula HI, wherein Q, X, Y, Z, R_l5 R₂ and R are as defined above, with an oxime of formula IVc, wherein R is as defined above, into a hydroxamic acid compound of formula He and then either heating the latter in a suitable diluent and/or treating it with a suitable base, as described above in connection with the preparation of compounds of formula la.

m lie

Ic

Suitable diluents and bases are those already mentioned above.

If desired, the reaction mixture can be converted directly into the compounds of formula Ic "in situ" at elevated temperature and/or with the addition of an excess of base as described above without isolating the compounds of formula He. The reaction temperatures can also be varied within a wide range of from approximately -10°C up to the boiling temperature of the solvent used, preferably from approximately 0°C to approximately +80°C.

The rearrangement of compounds of formula II to form compounds of formula Id, wherein X, Y, Z, Rj, R₂ and R₃ are as defined under formula I and A is hydrogen, is effected in a similar manner by reacting a compound of formula Ild, wherein X, Y, Z, R_1? R₂ and R₃ are as defined above and A is hydrogen, preferably in the presence of a diluent as indicated above and in the presence of a suitable base as described above.

The base used in this case is preferably sodium hydride.

Compounds of formula III wherein Q is chlorine or bromine (formula m") can be prepared by reacting an acid of formula V with a chlorinating agent, such as phosphorus oxychloride, thionyl chloride, oxalyl chloride or phosgene, phosphorus pentachloride, phosphorus oxybromide, especially phosphorus oxychloride, in the presence of an auxiliary base, such as, for example, triethylamine, dimethylaniline or pyridine and, where appropriate, in an auxiliary solvent, such as a hydrocarbon, for example toluene, a chlor¬ inated hydrocarbon, for example methylene chloride, an ether, for example tetrahydro¬ furan, in a temperature range of from -20° up to the reflux temperature of the reaction mixture, preferably from -5°C up to room temperature.

v

The corresponding acid chloride of formula DI" can be further reacted "in situ", without isolation, with the corresponding amine of formula IV, or with the hydrazine of formula IVa or the oxime of formula IVc, and, where appropriate, in the presence of an additional base selected from those mentioned above, such as, for example, triethylamine, 1,8-diaza- bicyclo[5.4.0]undec-7-ene or imidazole. This reaction is carried out in a temperature range of from approximately -20°C up to the reflux temperature of the auxiliary solvent used, preferably from -5°C to room temperature. The corresponding halogenating agent is used in stoichiometric amount or in excess. If a base is added as acid-binding agent, that base is preferably used in stoichiometric amount or in slight excess.

If desired, an acid of formula V can also be converted using from 0.50 to 0.55 equivalents of phosphorus oxychloride and a slight excess of from 2.0 to approximately 3.0 equiv¬ alents of triethylamine into the corresponding more stable acid anhydride of formula HI' and the latter can then be reacted as described above with an amine of formula IV, or with a hydrazine of formula IVa or an oxime of formula IVc.

Compounds of formula II wherein A is 2,4,6-triisopropylsulfonyl, imidazolyl, triazolyl, 2-thionothiazolidin-3-yl or N,N'-dicyclohexylisoureidyl can also be prepared from compounds of formula V in accordance with the conversion processes known to the person skilled in the art from the literature using l-(2,4,6-triisopropylphenylsulfonyl)- imidazole (Y.A. Berlin et al., Tetrahedron letters 1973. 1353), l-(2,4,6-triisopropyl- phenylsulfonyl)-lH-l,2,4-triazole (N. Katagiri et al., Chem. Commun. 1974. 325), 1,1'- carbonyldiimidazole, l, -carbonyl-di((l,2,4)triazole) (H.A. Staab, Angew. Chem. 74, 407 (1962)), thiazolylidine-2-thione (Y. Nagao eLal., Tetrahedron letters, 21, 841 (1980)) or dicyclohexylcarbodiimide. In this case too, it is not necessary to isolate the intermediate in order to convert it "in situ" as described above with a hydrazine of formula IVa or an oxime of formula IVc into a compound of formula Ha and la or He and Ic.

Compounds of formula HI¹ (acid anhydrides) are known from EP-A-0493 321. Compounds of formula V are either known (for example from EP-A-0249708 or EP-A-0287 079) or can be prepared in accordance with the processes described therein, for example by condensing a compound of formula VI in which L is a leaving group, such as fluorine, chlorine, methanesulfonyl, ethanesulfonyl or benzylsulfonyl, with a salicylic acid compound of formula VII in the presence of a suitable auxiliary base, such as potassium carbonate, potassium hydroxide, sodium hydride, and in the presence of a suitable auxiliary solvent, such as acetone, methyl ethyl ketone, acetonitrile, dimethyl- formamide or dimethyl sulfoxide (temperature range from 0° up to the reflux temperature, preferably from 10° to 60°).

VI vπ

Compounds of formulae IVa, IVc, VI, VII, VE, IX and X are either known or can be prepared in accordance with known processes.

Some of the compounds of formula II are known from British Application GB 2237 570 and from European Application EP 0469711 and can be prepared as described therein. The compounds of formula II that are novel, referred to hereinafter as compounds of formula He, have a pronounced herbicidal and plant-growth-regulating action and the invention accordingly relates also to these. In the novel compounds of formula He

R₅ is hydrogen or methyl and R₆ is as defined under formula I.

Especially preferred among these compounds are those wherein

R₅ is hydrogen and Rg is 2-chlorophenyl, 2-fluorophenyl, o-tolyl or 4-chlorophenyl.

The compounds of formula I are generally used successfully at rates of application of from 0.001 to 3 kg/ha, especially from 0.005 to 1 kg/ha. The concentration required to achieve the desired effect can be determined by experiment. It depends on the mode of action, the stage of development of the cultivated plant and the weed, and on the application (place, time, method) and, in dependence on those parameters, may vary within a wide range.

The compounds of formula I are distinguished by growth-inhibiting and herbicidal properties which make them excellently suitable for use in crops of useful plants, especially in cereals, cotton, soybeans, rape, maize and rice.

The invention relates also to herbicidal and plant-growth-regulating compositions that comprise a novel compound of formula I, and to methods of inhibiting plant growth.

Plant growth regulators are substances that bring about agronomically desirable biochemical and/or physiological and/or morphological changes in/to the plant.

The active ingredients incorporated in the compositions according to the invention influence plant growth in different ways depending on the time of application, the concen¬ tration, the method of application and the environmental conditions. Plant growth regulators of formula I can, for example, inhibit the vegetative growth of plants. This mode of action is valuable in the case of lawn areas, in the cultivation of ornamentals, in fruit plantations, in the case of roadside embankments and in sports fields and industrial sites, but also in the specific inhibition of side-shoots, as in the case of tobacco. In agriculture, inhibition of the vegetative growth of cereals leads, owing to a strengthening of the stalk, to reduced lodging, and similar agronomic effects are achieved in rape, sunflowers, maize and other cultivated plants. Moreover, by inhibiting the vegetative growth it is possible to increase the number of plants per unit area. Another field of application for growth inhibitors is the selective control of cover plants in plantations or widely spaced crops which is achieved by greatly inhibiting the growth of the cover crops without killing them, so that competition with the main crop is eliminated but the agron¬ omically positive effects, such as erosion prevention, fixing of nitrogen and loose soil structure, are preserved.

A method of inhibiting plant growth is to be understood as being a method of controlling a plant's natural development without changing its life-cycle, as determined by genetic characteristics, in the sense of mutation. The method of regulating growth is applied at a time in the plant's development that has to be determined for each individual case. The compounds of formula I can be applied pre- or post-emergence, for example to the seeds or seedlings, to roots, tubers, stalks, leaves, blossoms or other parts of the plant. This can be done, for example, by applying the compound as such or in the form of a composition to the plants, and/or by treating the plant's nutrient medium (soil).

Various methods and techniques are suitable for the use of the compounds of formula I or of compositions comprising them for regulating plant growth, for example the following:

i) Seed dressing a) Dressing the seeds with an active ingredient formulated as a wettable powder, by shaking in a container until the formulation is uniformly distributed over the surface of the seeds (dry dressing). Up to 4 g of compound of formula I (in the case of a 50 % formulation: up to 8.0 g of wettable powder) are used per 1 kg of seed.

b) Dressing the seeds with an emulsifiable concentrate of the active ingredient or with an aqueous solution of the compound of formula I formulated as a wettable powder according to method a) (wet dressing).

c) Dressing by soaking the seeds for a period of from 1 to 72 hours in a liquor containing up to 1000 ppm of compound of formula I and, if desired, subsequently drying the seeds (seed soaking).

Seed dressing or treatment of the germinated seedling are naturally the preferred methods of application because the treatment with the active ingredient is then directed wholly at the target crop. From 0.001 g to 4.0 g of active ingredient are normally used per 1 kg of seed, although, depending on the method employed, which also allows the addition of other active ingredients or micronutrients, amounts that exceed or fall short of the specified concentration limits may be employed (repeat dressing).

ii) Controlled release of active ingredient

A solution of the active ingredient is applied to mineral granulated carriers or polymerised granules (urea/formaldehyde) and dried. If required, a coating may be applied (coated granules), which allows the active ingredient to be released in metered amounts over a specific period of time.

The compounds of formula I are used in unmodified form, as obtainable from synthesis, or, preferably, together with the adjuvants conventionally employed in formulation technology, and are therefore formulated in known manner e.g. into emulsifiable concentrates, directly sprayable or dilutable solutions, dilute emulsions, wettable powders, soluble powders, dusts, granules, and also encapsulations in e.g. polymer substances. As with the nature of the compositions, the methods of application, such as spraying, atomising, dusting, wetting, scattering or pouring, are chosen in accordance with the intended objectives and the prevailing circumstances.

The formulations, i.e. the compositions, preparations or mixtures comprising the compound (active ingredient) of formula I and, where appropriate, one or more solid or liquid adjuvants, are prepared in known manner, e.g. by homogeneously mixing and/or grinding the active ingredients with extenders, e.g. solvents, solid carriers and, where appropriate, surface-active compounds (surfactants).

Suitable solvents are: aromatic hydrocarbons, preferably the fractions containing 8 to 12 carbon atoms, such as mixtures of alkylbenzenes, e.g. xylene mixtures or alkylated naph¬ thalenes; aliphatic and cycloaliphatic hydrocarbons such as paraffins, cyclohexane or tetrahydronaphthalene; alcohols such as ethanol, propanol or butanol; glycols and their ethers and esters, such as propylene glycol or dipropylene glycol ether, ketones such as cyclohexanone, isophorone or diacetone alcohol, strongly polar solvents such as N-methyl-2-pyrrolidone, dimethyl sulfoxide or water; vegetable oils and their esters, such as rape oil, castor oil or soybean oil; and, where appropriate, also silicone oils.

The solid carriers used, e.g. for dusts and dispersible powders, are normally natural mineral fillers such as calcite, talcum, kaolin, montmorillonite or attapulgite. In order to improve the physical properties it is also possible to add highly dispersed silicic acid or highly dispersed absorbent polymers. Suitable granulated adsorptive carriers are porous types, for example pumice, broken brick, sepiolite or bentonite; and suitable nonsorbent carriers are, for example, calcite or sand. In addition, a great number of pregranulated materials of inorganic or organic nature can be used, e.g. especially dolomite or pulverised plant residues.

Depending on the nature of the compound of formula I to be formulated, suitable surface- active compounds are non-ionic, cationic and/or anionic surfactants having good emulsifying, dispersing and wetting properties. The term "surfactants" will also be understood as comprising mixtures of surfactants. Both so-called water-soluble soaps and water-soluble synthetic surface-active compounds are suitable anionic surfactants.

Suitable soaps are the alkali metal salts, alkaline earth metal salts or unsubstituted or subs¬ tituted ammonium salts of higher fatty acids

the sodium or potassium salts of oleic or stearic acid, or of natural fatty acid mixtures which can be obtained e.g. from coconut oil or tallow oil. Mention may also be made of fatty acid methyltaurin salts.

More frequently, however, so-called synthetic surfactants are used, especially fatty alcohol sulfonates, fatty alcohol sulfates, sulfonated benzimidazole derivatives or alkylarylsulfon¬ ates.

The fatty alcohol sulfonates or sulfates are usually in the form of alkali metal salts, alkaline earth metal salts or unsubstituted or substituted ammonium salts and contain a Cg-C₂₂alkyl radical, which also includes the alkyl moiety of acyl radicals, e.g. the sodium or calcium salt of lignosulfonic acid, of dodecyl sulfate or of a mixture of fatty alcohol sulfates obtained from natural fatty acids. These compounds also comprise the salts of sulfated and sulfonated fatty alcohol/ethylene oxide adducts. The sulfonated benz¬ imidazole derivatives preferably contain 2 sulfonic acid groups and one fatty acid radical containing 8 to 22 carbon atoms. Examples of alkylarylsulfonates are the sodium, calcium or triethanolamine salts of dodecylbenzenesulfonic acid, dibutylnaphthalenesulfonic acid, or of a condensate of naphthalenesulfonic acid and formaldehyde.

Also suitable are corresponding phosphates, e.g. salts of the phosphoric acid ester of an adduct of p-nonylphenol with 4 to 14 mol of ethylene oxide, or phospholipids.

Non-ionic surfactants are preferably polyglycol ether derivatives of aliphatic or cyclo- aliphatic alcohols, saturated or unsaturated fatty acids and alkylphenols, said derivatives containing 3 to 30 glycol ether groups and 8 to 20 carbon atoms ir the (aliphatic) hydro¬ carbon moiety and 6 to 18 carbon atoms in the alkyl moiety of tht alkylphenols.

Further suitable non-ionic surfactants are the water-soluble adducts of polyethylene oxide with polypropylene glycol, ethylenediaminopolypropylene glycol and alkylpolypropylene glycol containing 1 to 10 carbon atoms in the alkyl chain, which adducts contain 20 to 250 ethylene glycol ether groups and 10 to 100 propylene glycol ether groups. These compounds usually contain 1 to 5 ethylene glycol units per propylene glycol unit.

Representative examples of non-ionic surfactants are nonylphenolpolyethoxyethanols, castor oil polyglycol ethers, polypropylene/polyethylene oxide adducts, tributylphenoxy- polyethoxyethanol, polyethylene glycol and octylphenoxypolyethoxyethanol.

Fatty acid esters of polyoxyethylene sorbitan, e.g. polyoxyethylene sorbitan trioleate, are also suitable non-ionic surfactants.

Cationic surfactants are preferably quaternary ammonium salts which contain, as N-substiment, at least one Cs-C^al yl radical and, as further substiments, unsubstituted or halogenated lower alkyl, benzyl or hydroxy-lower alkyl radicals. The salts are preferably in the form of halides, methyl sulfates or ethyl sulfates, e.g. stearyltrimethylammonium chloride or benzyldi(2-chloroethyl)ethylammonium bromide.

The surfactants customarily employed in formulation technology arc described inter alia in the following publications:

- "Mc Cutcheon's Detergents and Emulsifiers Annual", Mc Publishing Corp., Glen Rock, New Jersey, 1988.

- M. and J. Ash, "Encyclopedia of Surfactants", Vol. I-iπ, Chemical Publishing Co.,

New York, 1980-1981.

- Dr. Helmut Stache "Tensid-Taschenbuch", Carl Hanser Verlag, Munich Vienna 1981.

The herbicidal compositions generally comprise 0.1 to 99 %, preferably 0.1 to 95 %, of a compound of formula 1, 1 to 99 % of a solid or liquid adjuvant and 0 to 25 %, preferably 0.1 to 25 %, of a surfactant.

Whereas commercial products will preferably be formulated as concentrates, the end user will normally employ dilute formulations.

The compositions may also comprise further additives such as stabilisers, for example vegetable oils and epoxidised vegetable oils (epoxidised coconut oil, rape oil or soybean oil), antifoams, for example silicone oil, preservatives, viscosity regulators, binders, tackifiers as well as fertilisers or other active ingredients for obtaining special effects. Preferred formulations are composed in particular of the following constituents (throughout, percentages are by weight):

Emulsifiable concentrates: Active ingredient: 1 to 20 %, preferably 5 to 10 % surface-active agent: 5 to 30 %, preferably 10 to 20 % liquid carrier: 15 to 94 %, preferably 70 to 85 %

Dusts:

Active ingredient: 0.1 to 10 %, preferably 0.1 to 1 % 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: 0.5 to 30 %, preferably 3 to 15 % solid carrier: 99.5 to 70 %, preferably 97 to 85 %

Preparation Examples:

The following Examples serve to illustrate the invention in more detail.

Preparation Example 1:

N-dimemylammo-N-(4,6-dimethoxy-2-pyrimidinyl)-2-hydroxy-benzamide (Example A1.001) can be prepared as follows:

1.61 g of N-d^ethylamino-[(4,6^dimethoxy-2-pyrimidinyl)-oxy]-benzamide (Example B 1.001) are added to a suspension of 0.163 g of 99 % sodium hydride in 50 ml of absolute tetrahydrofuran and the batch is stirred for 5 hours at room temperature. The reaction mixture is then poured onto ice-water and extracted three times with ethyl acetate. The organic phases are washed with sodium chloride solution and dried over magnesium sulfate, and the crude product, which is concentrated to dryness by evaporation, is recrystallised from acetone/hexane to give 1.29 g of N-dimethylamino-N-(4,6-dimethoxy- 2-pyrimidinyl)-2-hydroxy-benzamide (Example A1.001) in the form of a white crystal- lisate; ¹H-NMR(CDC1₃): 2.98, s, N(CH₃)₂; 3.70, s, 2xOCH₃; 5.80, s, CH, 6.65, txd, J=8xl Hz, 6.97, dxd, J=8xl Hz, 7.19, dxd, J=8xl Hz and 7.29, txd, J=8xl Hz, 4 aromatic protons, 10.42, s, OH.

Preparation Example 2:

N-(o-cMorophenyl)-N-(4,6-dimemoxy-2-pyrimidinyl)-2-hydroxy-benzamide (Example A1.008) can be prepared as follows:

1.91 g of N-(o-cUorophenyl)-2-[(4,6-dimemoxy-2-pyrimidinyl)-oxy]-benzamide (Example B 1.008) are dissolved in 30 ml of dichloromethane and 6.7 ml of triethylamine and the batch is stirred for 15 hours at room temperature. In order to complete the reaction, another 6.7 ml of triethylamine arc added and the batch is heated for a short period at the boiling temperature of the reaction mixture. It is then washed with water, dried over magnesium sulfate and concentrated by evaporation under reduced pressure to give pure N-(o-cMorophenyl)-N-(4,6-ά methoxy-2-pyrimidinyl)-2-hydroxy-benzamide (Example A1.008); ¹H-NMR(CDCl₃): 3.64, s, 2xOCH₃; 5.76, s, CH; 7.41, b, NH; 10.26, s, OH.

Preparation Example 3:

Bis-o-((4,6^dimeΛoxy-2-py-rimidinyl)oxy)benzoic acid anhydride can be prepared as follows:

27.6 g of bis-o-((4,6-dimethoxy-2-pyrimidinyl)oxy)benzoic acid are introduced into a solution of 25 g of triethylamine in 500 ml of dichloromethane. The solution is cooled to

-5°C and then treated at that temperature with a solution of 8 g of phosphorus oxychloride in 25 ml of dichloromethane. After stirring for 10 minutes, the solution is washed briefly twice with 500 ml of ice-water each time. The organic phase is dried and concentrated by evaporation. Recrystallisation with ethyl acetate/hexane (7:8) gives 24.2 g of pure bis-o-

((4,6-dimethoxy-2-pyrimidinyl)oxy)benzoic acid anhydride; m.p.: 120-122°C.

Preparation Example 4:

N-methoxy-N-(4,6^dimethoxy-2-pyrimidinyl)-2-hydroxy-benzamide (Example A3.001) can be prepared as follows:

6.4 g of bis-o-((4,6-dimethoxy-2-pyrimidinyl)oxy)benzoic acid anhydride are taken up in 25 ml of toluene and treated in succession at 20°C with 1.1 g of O-methylhydroxylamine hydrochloride and 7.3 g of triethylamine. The batch is stirred for 1 hour at room tempera¬ ture and then taken up in ethyl acetate, washed once with water, once with saturated sodium hydrogen carbonate solution and once with saturated sodium chloride solution. The crude product, which is dried over magnesium sulfate and concentrated by evap¬ oration, is chromatographed on silica gel with 30 % ethyl acetate in hexane to give pure N-memoxy-N-(4,6^άιmethoxy-2-pyrimidinyl)-2-hydroxy-benzamide in the form of a resin-like product; ¹H-NMR(CDC1₃): 3.67, s, 2xOCH₃; 4.13, s, NOCH₃, 5.81, s, CH, 10.12, s, OH.

Preparation Example 5:

<E> and <Z> N-[(benzyUdene)ammo]-N-(4,6-dime oxy-2-pyrimidinyl)-2-hydroxy-benz- amide (Example A2.001) can be prepared as follows:

6.7 g of bis-o-((4,6^dimemoxy-2-pyrimid yl)oxy)benzoic acid anhydride dissolved in 30 ml of toluene are treated in succession at O°C with 0.7 g of hydrazine hydrate and 7.7 g of triethylamine. The batch is stirred for 30 minutes and then 1.6 g of benzaldehyde are added. The batch is stirred for 1 hour at room temperature, then taken up in ethyl acetate and washed once with potassium dihydrogen phosphate solution and once with sodium chloride solution, dried and concentrated by evaporation. The residue which remains is chromatographed on silica gel with ethyl acetate/hexane 1:6 to give the one isomer of N-[(benzy ene)ammo]-N-(4,6^dimethoxy-2-pyrimidinyl)-2-hydroxy-benzamide in the form of an oil; ¹H-NMR(CDC1₃): 3.89 s, OCH₃; 6.08, s, CH; 8.30, s, CH; 10.65, s, OH. Further elution with ethyl acetate/hexane 1 :3 gives the other isomer in crystalline form having a melting point of 103°C.

Preparation Example 6:

N-(m-chloro-o-tolyl)-2-[(4,6-dimethoxy-2-pyrimidinyl)-oxy]-6-fluorobenzamide (Example B 1.021) can be prepared as follows:

4.2 g of 2-[(4,6-dimeΛoxy-2-pyrimiάιnyl)-oxy]-6-fluorobenzoic acid and 8.8 g of triethyl¬ amine in 100 ml of diethoxymethane are treated drop wise at -5°C with 2.2 g of phos¬ phorus oxychloride in 8.5 ml of diethoxyethane. The batch is stirred for 15 minutes at that temperature and then 5.2 g of 3-chloro-o-tolylhydrazine hydrochloride are added in portions over a period of 5 minutes. After stirring for 15 hours, the reaction mixture is extracted three times against ice-water with tert-butyl methyl ether and washed once with 2N sodium hydroxide solution, once with IN hydrochloric acid and once with saturated sodium chloride solution. The batch is then dried over magnesium sulfate and concen¬ trated to dryness by evaporation. Column chromatography (eluant: ethyl acetate/hexane 1:2) and crystallisation from diethyl ether give pure N-(m-chloro-o-tolyl)-2-[(4,6- dimethoxy-2-pyrimidinyl)-oxy]-6-fluorobenzamide: m.p.: 164-166 °C.

It is also possible to prepare the compounds listed in the following Tables 1 A, 2A, 3A and 4A, and IB, 2B, 3B and 4B in a manner analogous to that described in Examples 1, 2, 4, 5 and 6.

Table 1A: Compounds of formula la':

la'

Comp. No. X R⁵ R⁶ m.p.[°C] phys. data

A1.048 C-Cl C-H H o-tolyl A1.049 o-ethyphenyl A1.050 o-xylyl A1.052 CH₃ A1.053 CH₂CH₂CH₂CH₂CH₃ A1.054 C(CH₃)₃ A1.055 CH, CH₃ A1.056 C-F pyridyl A1.057 phenyl A1.058 N A1.059 C-H H m-methoxyphenyl A1.060 p-tolyl A1.061 o-fluorophenyl A1.061 o,p-difluorophenyl A1.062 o,p-dichlorophenyl A1.063 CH₃ A1.064 CH₂CH3 A1.065 CH₂CH₂CH₃ A1.066 CH₂CH₂C=N A1.067 CH₂CF₃ A 1.068 CH₂COOCH₂CH₃

Continuation of Table 1A: Compounds of formula la'

Table 2A: Compounds of formula lb':

Table 3 A: Compounds of formula Ic':

Ic'

ε. NOCH₃;

OCH₃; 1033, s, OH. m, OH.

ε, NOCH₂;

Table 4A: Compounds of formula Id':

Table IB: Compounds of formula Ila':

CH3O

b, NH.

Comp. No. R⁵ m.p.[°C] / phys. data

C-H H o-tolyl o-ethylphenyl o-xylyl

CH₃

CH₂CH CH₂CH₂CH₃

C(CH₃)₃

CH, CH₃ pyridyl phenyl

H m-methoxyphenyl p-tolyl o-fluorophenyl o_.p-difluorophenyl o_.p-dichlorophenyl

CH₃

CH₂GH₃

(_-H₂CH₂CH₃

CH₂CH₂C≡N

CH₂CF₃

CH₂COOCH₂CH₃

Continuation Table IB: Compounds of formula la'

Table 2B: Compounds of formula lib':

Table 3B: Compounds of formula He':

He'

Table 4B: Compounds of formula ϋd':

Biological Examples

Example Bl: Preemergence herbicidal action

In a greenhouse, immediately after the test plants (a number of weeds, both monocots and dicots) have been sown in seed trays, the surface of the soil is treated with an aqueous spray mixture at a rate of application of 3 kg test compound/hectare.

The test compounds are formulated preferably as an emulsifiable concentrate (EC) and are diluted with water to the desired concentration immediately before application. Insoluble compounds are formulated as a wettable powder (WP) using kaolin as inert carrier. The wettable powder is suspended in water immediately before application. The concentrations in g test compound/ha are based on the soil surface in the containers, unless otherwise indicated. The spray volume is 10001 ha (corresponding to 100 ml/m²).

The seeds of the plants are sown in plastics plant pots of various sizes containing heat- sterilised (steamed) soil (agricultural soil 2.6 % peat, 20 % clay, 30 % poor clay, 47 % sand). The plants are kept in the greenhouse at a moderate temperature (17 - 25°C in winter, 18 - 35°C in summer) (humidity 30 - 90 %). The period of illumination is from 13 to 16 hours/day and, if necessary, artificial light (15 000 to 18000 lux) is used. Artificial lighting is also activated automatically if the intensity of daylight is inadequate.

3 weeks later, the herbicial action is evaluated using a linear scale of three ratings (necrosis, chlorosis, reduction, deformation) in comparison with an untreated control group (2 = 80-100 % damage, 1 = 30-79 % damage, 0 = 0-29 % damage).

The compounds of formula I described in the Examples exhibit strong herbicidal activity in this test.

Examples of the good herbicidal activity of the compounds of formula I described in the Tables of the present Application are listed in Table B 1 :

Comp. No.

The abbreviations in the Table have the following meanings:

SORG Sorghum halepense Johnson grass ECHI Echinochloa crus-galli Barnyard grass AVEN Avena fatua Wild oat ALOP Alopecurus myosuroides Black grass CHEN Chenopodium album Lambs quarters STEL Stellaria media Chickweed ABUT Abutilon theophrasti Velvet leaf MATR Matricaria chamomilla Wild chamomile CASS Cassia obtusifolia Sickle pod

Example Bl': Preemergence herbicidal action

The seeds of monocotyledonous and dicotyledonous test plants are sown in plastics pots in standard soil. Immediately after sowing, the test compounds in an aqueous suspension corresponding to a concentration of 2 kg a.i./ha arc sprayed on (500 1 water/ha). The test plants are then cultivated under optimum conditions in a greenhouse. 3 weeks later, the test is evaluated using a scale of nine ratings (1 = complete destruction, 9 = no action). Ratings of from 1 to 4 (especially 1 to 3) denote a good to very good herbicidal activity.

Table Bl': preemergence action:

Avena Setaria Sinapis Stellaria

2 1 2 2 2 1 2 2 2 1 3 3 2 1 3 3 2 1 3 3

3 1 3 2

Example B2: Postemergence herbicidal action (contact herbicide)

A number of weeds, both monocots and dicots, are treated postemergence (in the 2- to 6-leaf stage) with an aqueous active ingredient dispersion at a rate of 3 kg of test compound per hectare.

The test compounds are formulated preferably as an emulsifiable concentrate (EC) and are diluted with water to the desired concentration immediately before application. Insoluble compounds are formulated as a wettable powder (WP) using kaolin as inert carrier. The wettable powder is suspended in water immediately before application.

The concentrations in g test compound/ha are based on the soil surface in the containers, unless otherwise indicated. The spray volume is 5001/ha.

The seeds of the plants are sown in plastics plant pots of various sizes containing heat- sterilised (steamed) soil ('Optima' soil 80 % peat, 20 % loess). The plants are kept in a greenhouse at a moderate temperature (17 - 25°C in winter, 18 - 35°C in summer) (humidity 30 - 90 %). The period of illumination is from 13 to 16 hours/day and, if necessary, artificial light (15 000 to 18000 lux) is used. Artificial lighting is also activated automatically if the intensity of daylight is inadequate.

3 weeks later, the herbicial activity is evaluated using a linear scale of three ratings (necrosis, chlorosis, reduction, deformation) in comparison with an untreated control group (2 = 80-100 % damage, 1 = 30-79 % damage, 0 = 0-29 % damage).

The compounds described in the Examples exhibit strong herbicidal activity in this test too.

Examples of the good herbicidal activity of the compounds of formula I described in the Tables of the present Application are listed in Table B2:.

Table B2: Postemergence herbicidal action:

Comp. No

The abbreviations in the Table have the following meanings:

Example B2': Postemergence herbicidal action (contact herbicide) A number of weeds, both monocots and dicots, are sprayed postemergence (in the 4- to 6-leaf stage) with an aqueous dispersion of the test compound at a rate of 2 kg of test compound per hectare and the plants are kept at 24°-26°C and 45-60 % relative humidity. The test is evaluated 15 days after treatment

3 weeks later, the herbicidal activity is evaluated using a scale of nine ratings (1 = complete destruction, 9 = no action) in comparison with an untreated control group. Ratings from 1 to 4 (especially from 1 to 3) denote a good to very good herbicidal activity. Ratings of from 6 to 9 (especially from 7 to 9) denote good tolerance (especially in the case of cultivated plants).

Table B2': postemergence action:

Test plant: Avena Setaria Sinapis Stellaria Comp. No.

A1.010 1 2 1 1 A1.013 2 2 3 3 A1.016 2 2 2 2

Example B3: Herbicidal action for paddy rice

The seeds of the plants are sown in plastics beakers or plastics boxes of various sizes that are closed at the bottom and contain fertilised soil. The soil is heat-sterilised (steamed) and contains approximately 80 % (w/v) loam and 20 % peat and also 0.05 % Nutricote (16/10/10) and 0.05 % 'Plantamaag' as fertiliser. The plants are kept in a special greenhouse compartment at a high temperature (20 - 35°C) and high humidity (60 - 80%), the humidity being maintained at a constant level by a sprinkler system. The period of illumination is from 13 to 16 hours/day and, if necessary, artificial light (15 000 to 18000 lux) is used. Artificial lighting is also activated automatically if the intensity of daylight is inadequate. The test compounds are formulated preferably as an emulsifiable concentrate (EC) and are diluted with water to the desired concentration immediately before application. Insoluble compounds are formulated as a wettable powder (WP) using kaolin as inert carrier. The wettable powder is suspended in water immediately before application.

The concentrations in g active ingredient/ha are based on the soil surface in the containers, unless otherwise indicated. The spray volume is 5001/ha.

The tests are evaluated after 3 or 4 weeks (postemergence or preemergence treatment) using a linear scale of ten ratings (10 = complete destruction, 0 = no action) in comparison with an untreated control group. The compounds of formula I exhibit selective herbicidal activity against weeds in this test too.

Formulation Examples for compounds of formula I (throughout, percentages are by weight)

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

2. Emulsifiable concentrates compound of Tables calcium dodecylbenzenesulfonate

octylphenol polyethylene glycol ether (4-5 mol of ethylene oxide) 3 % 3 % castor oil polyethylene glycol ether

(36 mol of ethylene oxide) 4 % 4 % cyclohexanone 30 % 10 % xylene mixture 50 % 79 %

Emulsions of any required concentration can be obtained from these concentrates by dilution with water.

3. Dusts compound of the Tables talcum kaolin

Ready-for-use dusts arc obtained by homogeneously mixing the carriers with the active ingredient.

4. Extruder granules compound of the Tables sodium lignosulfonate carboxymethylcellulose kaolin

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

5. Coated granules compound of the Tables 3 % polyethylene glycol (mol. wt. 200) 3 % kaolin 94 %

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

The finely ground active ingredient is intimately mixed with the adjuvants, giving a suspension concentrate from which suspensions of any desired concentration can be obtained by dilution with water.

7. Salt solution compound of the Tables 5 % isopropylamine 1 % octylphenol polyethylene glycol ether (78 mol of ethylene oxide) 91 %

The compounds of formula I are used in unmodified form or, preferably, in the form of compositions together with the adjuvants conventionally employed in formulation technology, and are therefore formulated in known manner e.g. into emulsifiable concentrates, directly sprayable or dilutable solutions, dilute emulsions, wettable powders, soluble powders, dusts, granules, and also encapsulations in e.g. polymer substances. As with the nature of the compositions, the methods of application, such as spraying, atomising, dusting, scattering or pouring, are chosen in accordance with the intended objectives and the prevailing circumstances.

Claims

What is claimed is:

1. A pyrimidinyl- or triazinyl-salicyl- or -picolyl-amide of formula I

wherein

A is hydrogen or a group

(Q2) or °— R*. (Q3);

X is nitrogen or C-R₄;

Y is nitrogen or, if Z is nitrogen, also is methine, or methine substituted by fluorine or by chlorine; z is methine, methine substituted by fluorine, chlorine or by methyl, or is nitrogen;

R, is C^alkyl, C₂.₃alkynyl, cyclopropyl, chloromethyl, difluoromethyl, trifluoro¬ methyl, methoxy, ethoxy, difluoromethoxy, C^alkylamino, dimethylamino, diethylamino or methoxymethylamino;

R is hydrogen, methyl, fluorine, chlorine, C^alkoxy, difluoromethoxy, trifluoro- ethoxy, methylthio or ethylthio;

R, is hydrogen, fluorine, chlorine, methyl, methoxy or, together with R₄, -CH=CH-CH=CH- or -CH=CH-CH=N-;

R„ is hydrogen, fluorine, chlorine, bromine, iodine, C^al-kyl, trifluoromethyl, vinyl, Ci-₃-dkoxy, 2-propenyloxy, 2-propynyloxy, difluoromethoxy, benzyloxy, phenoxy, phenylthio, phenyl, thienyl, pyrazolyl, imidazolyl or triazolyl; or phenoxy, phenyl¬ thio, phenyl, thienyl, pyrazolyl, imidazolyl or triazolyl each of which is mono- or di-substituted by fluorine, chlorine, bromine, methyl or by methoxy; R₅ is hydrogen or C^alkyl;

R₆ is hydrogen or C^alkyl that may be unsubstituted or mono- or poly-substimted by fluorine or mono-substituted by chlorine, bromine, hydroxy, Cj ^alkoxy, carboxy, C^alkoxycarbonyl, cyano, vinyl, ethynyl or by phenyl, it being possible for the phenyl group for its part to be mono- or poly-substimted by fluorine, chlorine, bromine, methyl, ethyl, trifluoromethyl, methoxy, carboxy, C^alkoxycarbonyl or by nitro; phenyl, naphthyl, or phenyl or naphthyl each of which is mono- or poly-substimted by fluorine, chlorine, bromine, iodine, C_j^alkyl, trifluoromethyl, C_j^alkoxy, difluoromethoxy, cyano, nitro or by C^alkoxycarbonyl; pyridyl, pyrazinyl, pyrimidinyl or quinolinyl; or pyridyl, pyrazinyl, pyrimidinyl or quinolinyl each of which is mono- or poly-substimted by fluorine, chlorine, methyl, methoxy or by trifluoromethyl;

C^alkylcarbonyl, benzoyl, or benzoyl mono- or poly-substimted by fluorine, chlorine, bromine, methyl, ethyl, trifluoromethyl or by methoxy;

aminocarbonyl, aminothiocarbonyl, or aminocarbonyl or aminothiocarbonyl each of which is mono- or di-substimted by C^alkyl or mono- substituted by phenyl, it being possible for the phenyl group to be mono- or poly- substimted by fluorine, chlorine, methyl or by methoxy; C^alkylsulfonyl, phenylsulfonyl, or phenylsulfonyl mono- or di-substimted by fluorine, chlorine, C^alkyl, trifluoromethyl or by methoxy; or R₅ and R_$ form together with the nitrogen atom to which they are bonded a 5-, 6- or 7-membered heterocyclic ring which may for its part contain one or two nitrogen atoms, an oxygen atom, a sulfur atom or a group -S(O)-, -S(O)₂-, -C(O)-, -C(O)O-, -C(O)S- -C(S)O- or -C(S)S- and/or may additionally be mono- or poly- substimted by C^alkyl or mono-substituted by benzyl, C^alkoxy, hyd-raxy-C^- alkyl or by C^alkoxy-C^alkyl;

R₇ is hydrogen, ^alkyl, C^alkylthio or, together with R₈, -CH₂CH2CH₂CH₂-, -CH₂CH₂CH₂CH₂CH₂- or -SCH₂CH₂S-;

R₈ is C alkyl, C₃_6Cycloalkyl, phenyl, or phenyl substituted by fluorine, chlorine, bromine, methyl, trifluoromethyl or by methoxy, or is C^alkoxy, C^alkylthio, Cι-₄alkoxycarbonyl or cyano; and

R₉ is hydrogen, C^alkyl, C₂-₆alkenyl, C^alkynyl, carboxy-C^alkyl, C_j^alkoxy- carbonyl-C^alkyl, benzyl, phenyl, or benzyl or phenyl each of which is mono- or poly-substimted by fluorine, chlorine, bromine, methyl, trifluoromethyl, nitro or by methoxy; or a salt of a compound of formula I.

2. A compound of formula I according to claim 1, wherein Y is nitrogen;

Z is methine or nitrogen;

R_x is methyl, dimethylamino or methoxy;

R₂ is methyl, methoxy, ethoxy or difluoromethoxy;

R₃ is hydrogen; and

R₄ is hydrogen, fluorine, chlorine, bromine, methyl, trifluoromethyl or methoxy.

3. A compound according to claim 1, wherein A. is the group Ql.

4. A compound according to claim 2, wherein Z is methine;

Ri is methoxy; R₂ is methoxy; R₄ is hydrogen, fluorine, chlorine, bromine, methyl, trifluoromethyl or methoxy; and

^Rs

/

A is a group ^N (Ql).

«6

5. A compound according to claim 4, wherein R₅ is hydrogen or methyl and R_$ is C^- alkyl, phenyl, or phenyl mono- or di-substimted by fluorine, chlorine, methyl, trifluoro¬ methyl, methoxy or by nitro; pyridyl or pyrazinyl, or pyridyl or pyrazinyl each of which is mono- or poly-substimted by fluorine, chlorine, methyl or by trifluoromethyl; or R₅ and Rg form together with the nitrogen atom to which they are bonded a 5- or 6-membered heterocyclic ring which may for its part contain a nitrogen atom or an oxygen atom and/or may additionally be mono- or di-substimted by C^alkyl or mono-substituted by C^- alkoxy-C₁.₂alkyl.

6. A compound according to claim 1, wherein Y is nitrogen;

Z is methine; R] is methoxy; R₂ is methoxy; R₃ is hydrogen;

R is hydrogen, fluorine, chlorine, bromine, methyl, trifluoromethyl or methoxy;

A is hydrogen or a group ° — ^ (Q3); and

R₉ is

benzyl, or benzyl mono- or di-substimted by fluorine, chlorine or by methyl.

7. A compound according to claim 1 selected from

N'-(2-cMOTθphenyl)-N-(4,6^dimemoxy-2-pyrimidinyl)-2-hydroxy-benzamide, N'-(2-methylphenyl)-N-(4,6-dimemoxy-2-pyrimidinyl)-2-hydroxy-benzamide, N'-(3-tτifluoromethylphenyl)-N-(4,6-dimemoxy-2-pyrimidinyl)-2-hydroxy-benzamide, N'-(3-cWoro-2-memylphenyl)-N-(4,6-dimemoxy-2-pyrimidinyl)-2-hydroxy-benzamide, N'-phenyl-N'-me yl-N-(4,6-dimemoxy-2-pvrimidinyl)-2-hydroxy-benzamide, N^,-(2-trifluoromemylphenyl)-N-(4,6^d-methoxy-2-pyrimidinyl)-2-hydroxy-benzamide, N'-(2,3-d-ιnethylphenyl)-N-(4,6-dimethoxy-2-pyrimidinyl)-2-hydroxy-benzamide, N'-(4-memoxyphenyl)-N-(4,6-dimemoxy-2-pyrimidinyl)-2-hydroxy-benzamide and N'-(4-cUoro-2-memylphenyl)-N-(4,6-dimethoxy-2-pyrimid-Jiyl)-2-hydroxy-benzamide.

8. A process for the preparation of a compound of formula I which comprises either heating a compound of formula II wherein A, X, Y, Z, R_lt R₂ and R₃ arc as defined under formula I in claim 1

π

in a suitable diluent and/or reacting it with a suitable base.

9. A compound of formula lie

wherein

R₅ is hydrogen or methyl and R₆ is as defined under formula I in claim 1.

10. A compound according to claim 9, wherein R₅ is hydrogen and Rg is 2-chlorophenyl, 2-fluorophenyl, o-tolyl or 4-chlorophenyl.

11. A herbicidal and plant-growth-inhibiting composition which comprises one or more pyrimidinyl- and triazinyl-salicyl- and -picolyl-amides of formula I according to claim 1.

12. A composition according to claim 11 which comprises from 0.001 % to 95 % by weight of compound of formula I according to claim 1.

13. A method of controlling undesired plant growth which comprises applying an effective amount of a compound of formula I according to claim 1 or of a composition according to claim 11 comprising that compound to the plants or the locus thereof.

14. A method according to claim 13 which comprises applying an amount of active ingredient of from 0.001 to 3 kg per hectare.

15. A method of regulating plant growth which comprises applying an effective amount of a compound of formula I according to claim 1 or of a composition according to claim 11 comprising that compound to the plants or the locus thereof.

16. A method according to claim 13 for the selective pre- or post-emergence control of weeds in crops of useful plants.