LU83355A1 - DIPHENYL ETHERS WITH HERBICIDE ACTIVITY - Google Patents

Description

-2- B. 73.999

DP - AM

The present invention relates to substituted phenphenyl ethers having herbicidal activity, their preparation and weed control using these compounds.

The present invention more particularly relates to substituted diphenyl ethers represented by the following general structural formula:

0 R P

It I. Il, ___ ^ C - N — a1 — C-À- Y— (oy ~ 0— (Çy ~ z in which: A represents an oxygen or sulfur atom, X represents a hydrogen atom or an atom halogen, Y represents a halogen atom or the tri-fluoromethyl radical, Z represents a halogen atom, the nitro or cyano radical, R represents a hydrogen atom or an al-kyl radical containing from 1 to 4 carbon atoms,] -3-

AT

R represents a monosubstituted alkylidene or alkylidene radical containing from 1 to 3 carbon atoms, where the substituent is an alkyl group containing from 1 to 4 carbon atoms, and 2 R represents a hydrogen atom, an alkyl or alkoxy group containing from 1 to 10 carbon atoms, a cycloalkyl group containing 3 to 8 carbon atoms or an agronomically acceptable ionic species.

As examples of the halogen atoms represented by X, Y and Z in the above-mentioned formula, mention may be made of bromine, chlorine or fluorine, preferably bromine or chlorine. Some alkyl groups 2 which R and R represent are, for example, the following radicals: methyl, ethyl, n-propyl, isopropyl, n-butyl, iso-butyl, t-butyl, n-amyl, hexyl, heptyl, ï octyl, iso-octyl, nonyl, decyl and the like. Mention may be made, as examples of alkylidene radicals represented by R, of the methylidene, ethylidene and propylidene radicals. As suitable alkoxy and cycloalkyl groups represented by R, mention may be made of methoxy, ethoxy, butoxy, octoxy, cyclopentyl, cyclohexyl, cycloheptyl and the like. As examples of agronomically acceptable ionic species, represented by R, there may be mentioned alkali metals, such as sodium, potassium or lithium, alkaline earth metals, such as barium or calcium, ammonium and alkyl ammonium and alkanol ammonium derivatives having 1 to 4 carbon atoms.

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In accordance with the present invention, the compounds of the above general formula are believed to exert herbicidal activity. As specific examples of compounds which correspond to the above formula and which constitute the preferred compounds of the invention, mention may be made of the following substances: 5- (2 *, 4 '-dichlorophenoxy) -2-nitrobenzoyl_7 glycinate d 'ethyl; N- / 5- (2 ', 4 * -dichlorophenoxy) -2-nitrobenzoyl_7 isopropyl glycinate; N-sec-butyl-N- / 5- (2 ’, 4'-dichlorophenoxy) - 2-nitrobenzoyl_7 ethyl glycinate; N - / ”5- (2’, 4 * -dichlorophenoxy) -2-nitrobenzoyl_7 glycine; N- / ~ "21, 4'-dichlorophenoxy) -2-nitrobenzoyl_7 ethyl alaninate; N - /” 5- (methyl 2', 4'-dichlorophenoxy) -2-nitrobenzoyl_7 glycinate; N- / 2 '-chlor 0-4'-trifluorome thylphenoxy) - 2-nitrobenzoyl_7 ethyl glycinate; N- £ ~ 5- (2 ', 4'-? Dichlorophenoxy) -2-nitrobenzoyl_7 sec-butyl glycinate; N - / ”5- (2 ', 4'-dichlorophenoxy) f2-nitrobenzoyl__7 propyl glycinate; N- / ~ 5- (2', 4'-dichlorophenoxy) -2-nitrobenzoyl_7 ~ n-amyl glycinate; N- / ~ 5- (2 ', Isopropyl 4'-dichlorophenoxy) -2-nitrobenzoyl-3-aminopropionate; N- / 5- (2 ', 4'-dichlorophenoxy) -2-nitroben2oyl_J7gly-cinate; N- / 5- (2'- isopropyl chloro-4'-trifluororaethyl-phenoxy) -2-nitrobenzoyl_7glycine; Ej [~ 5- (2 '-chloro-4' -trifluoromethylphenoxy) -2-nitrobenzoyl_7glycinate; N- / 5- (2 '-chloro-4 * -trif luoromethyl) -2-nitro-benzoyl__7 methyl glycinate; N - / - * 5- (2 '-chloro-4' -trif luoromé thylphenoxy) -2-nitrobenzoyl_7 sec-butyl glycinate; N- / ~ 2 '- 4-chloro-trifluoromethylphenoxy) -2-nitrobenzoyl__7alanin ethyl ate; N- / ~ 5- (2r-chloro-4’-trifluoromethylphenoxy) -2-nitrobenzoyl-3-aminopropionate -5-.

Among these compounds, those which have a trifluorcmethyl group in position Y of the general formula have been found to be quite particularly effective.

It should obviously also be understood that the scope of the invention extends to stereoisomers and optical isomers of the compounds represented by the general formula above.

The compounds in accordance with the invention can typically be synthesized, for example by reacting a suitably substituted benzoyl halide on at least the stoichiometric amount of an appropriately substituted amino ester, using techniques well known to specialists. The substituted benzoyl halides and the substituted amino esters can be obtained from commercial sources or they can be prepared using known techniques. More particularly, at least one stoichiometric amount of substituted benzoyl halide is added , with stirring, with the substituted aminoester, preferably in the presence of an acid acceptor, such as, for example, triethylamine, pyridine, N, N-dimethylaniline, and the like. Since the reaction is exothermic, the substituted benzoyl halide is added in increasing fractions, so that the temperature of the reaction mixture does not rise appreciably above about 35 ° C. If desired, each of the reactants, namely the substituted benzoyl halide and the substituted amino ester or both can be dissolved in both an inert solvent, such as, for example, benzene, methylene chloride, chloroform, ethyl acetate, tetrahydrofuran and the like. At the end of the addition of the substituted benzoyl halide, the reaction mixture is brought to reflux and kept at reflux temperature until the reaction reaches the desired degree of completion. The reaction mixture is then cooled to ambient temperature and washed consecutively with dilute mineral acid, with dilute caustic product and water and the phases are allowed to separate. The diphenyl ether, substituted with the organic phase by any suitable technique such as, for example, evaporation, crystallization, vacuum drying and the like. If desired, more can be purified - the substituted diphenyl ether produced, for example by recrystallization.

Examples I to IX which follow illustrate the synthesis of certain specific substituted diphenyl ethers in accordance with the present invention.

EXAMPLE I

N- / 5- (2 ', 4’- dichlorophenoxy) -2-ethyl nitrobenzoyl_7 glycinate _________

A 1.03 g solution (0.01 g) was introduced into a 100 milliliter flask fitted with an addition funnel, a reflux condenser and a magnetic stir bar. mole) of ethyl ester of glycine and 1.0 g (0.01 mole) of triethylamine in 25 milliliters of benzene. The solution was stirred at room temperature and 3.450 g (0.01 mole) of 5- (2 ', 4'-dichlorophenoxy) -2-nitrobenzoyl chloride was added thereto dropwise. milliliters of benzene and exothermic heat has been given off. After the addition was complete, the mixture was stirred at room temperature for two hours and. it was then brought to reflux and kept for two hours at reflux temperature, then cooled to room temperature. The mixture was transferred to a separator funnel and washed separately with 30 milliliters of normal hydrochloric acid 1, 30 milliliters of water, 30 milliliters of normal sodium hydroxide 1 and 30 milliliters of water respectively. The organic layer was dried over magnesium sulfate and concentrated on a rotary evaporator at 55 ° C so as to obtain a rust-colored solid containing N- / ~ 5- (2 ', 4 * -dichlorophenoxy] 2-nitrobenzoyl_7 ethyl glycinate The solid was recrystallized in the minimum amount of a mixture of benzene and ligroin (30:70 vol / vol) so as to obtain a crystalline solid consisting of N- / ~ * 5- (2 ', 4'- dichlorophenoxy) -2-nitrobenzoyl_7 ethyl glycinate (72% yield), having a melting point of 110-112 ° C and a mass spectrum showing a molecular weight from 412 with fragments to 412, 310 and 236.

EXAMPLE II

N- / ~ 5- (2 *, 4'-dichlorophenoxy) -2-nitrobenzoyl_7 methyl glycinate _________

A solution of 0 was introduced into a three-tube flask, with a capacity of 100 milliliters, equipped with a reflux condenser, -a- with an addition funnel and a magnetic stir bar. , 89 g (0, Q1 mole) of glycine methyl ester and 1.0 g (0.01 mole) of triethylamine in 30 milliliters of tetrahydrofuran. While stirring the solution at room temperature, 3.45 g (0.01 mole) of 5- (2T, 4'-dichlorophenoxy) -2-nitrobenzoyl chloride in 20 milliliters of tetrahydrofuran was added thereto, the addition being done drop by drop. Exothermic heat was observed. After the addition was complete, it was refluxed with stirring for 2.5 hours, cooled to room temperature and then transferred to a separator funnel. It was then diluted with 50 milliliters of ethyl acetate and washed separately with 30 milliliters of normal hydrochloric acid 1 ^, 30 milliliters of normal sodium hydroxide 1 and 30 milliliters of water, respectively . The organic layer was separated, dried over magnesium sulfate and then concentrated on a rotary evaporator at 55 ° C so as to obtain a yellow syrup which crystallized on standing. The yellow matter crystallized out was then recrystallized from a solution of benzene and ligroin (30:70 vol / vol), so as to obtain a fluffy solid of tan color consisting of N- / ~ 5- (2 ', 4'- dichlorophenoxy) -2-nitrobenzoyl_7 methyl glycinate which had a melting point of 133-135 ° C, with a mass spectrum showing a molecular weight of 398.

2.5 g of material were obtained, corresponding to a yield of 63 percent.

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EXAMPLE III

N- / 5- (2 ', 4’-dichlorophenoxy) -2-nitrobenzoyl__7 sec-butyl glycinate _____________________

2.06 g (0.005 mole) of N- / ~ 5- (2 ', 4 * -dichlorophenoxy) -2-nitrobenzoyl__7 ethyl glycinate (prepared as described in Example I) was introduced into a flask. '' a capacity of 100 milliliters, equipped with a reflux condenser and a magnetic stir bar, and then 0.4 g (0.01 mole) of sodium hydroxide was introduced into 20 milliliters of water. The suspension was stirred and heated to reflux until all of the solid was dissolved (about 50 minutes) and then heated to reflux for an additional 10 minutes. The solution was cooled and then 20 milliliters of 10 percent hydrochloric acid was added thereto. It formed a solid sticky. The mass was diluted with 50 milliliters of water and extracted twice with 50 milliliters of ethyl acetate. The extracts were pooled, washed with water and then dried over magnesium sulfate. The solvent was removed using a rotary evaporator at 55 ° G and a light brown syrup of N- / ~ * 5- (2 ', 4 * -dichlorophé-noxy) -2-nitrobenzoyl_7glycine was obtained. had a mass spectrum showing a molecular weight of 384 ,, 'with fragments of 384 and 310.

A solution of 3.84 g of N-7 ~ 5- (2 ', 4'-dichlorophenoxy) -2-nitrobenzoyl_7glycine (prepared as indicated above) and 0.35 g of phenol acid was introduced. suif oni that in 50 milliliters of sec-hutanol in f -10- a balloon with a capacity of 100 milliliters which was attached to a Dean-Stark collector and equipped with a magnetic stir bar. The solution was stirred and heated to reflux while removing water azeotropically. After about 26 hours of reflux, the solution was cooled and the sec-butanol was removed using a rotary evaporator at 55 ° C. The residue was dissolved in 50 milliliters of methylene chloride and the solution was washed twice with 50 milliliters of normal sodium hydroxide 1 and once with 50 milliliters of water. The organic layer was then dried over magnesium sulfate and concentrated on a rotary evaporator at 55 ° C. A light red oil was formed which crystallized on standing so as to produce a crude product consisting of N- / 5- (2 ', 4'-dichlorophenoxy) -2-nitrobenzoyl_7 sec-butyl glycinate. The crude product was recrystallized from the minimum amount of a mixture of hot solvent of ethyl acetate and ligroin (25:75 vol / vol), so as to form a white solid consisting of N - / "" 5 - (2 ', 4'-dichlorophenoxy) -2- nitrobenzoyl_7gly ~ sec-butyl cinate with a molecular weight of 440, as determined by mass spectrography with fragments at 440, 567 and 510.

EXAMPLE IY

N- / ~ 5- (2 ', 4' -dichlorophenoxy) -2-nitrobenzoyl_7 isopropyl glycinate_

A solution of 5.84 g of N- / ~ 5- (2 ', 4'-dichlorophenoxy) -2-nitrobenzoyl_7glycine (prepared as described in Example III) and 0.35 g of was introduced. phenolsulfonic acid in 50 milliliters of isopropanol i

0V

-11- in a 1C0 milliliter flask, equipped with a Dean-Stark collector, a reflux condenser and a magnetic stir bar. The solution was brought to reflux and the water was removed azeotropically. After approximately 26 hours of reflux heating, the solution was cooled and the sec-butanol was removed using a rotary evaporator. 55 ° C, so as to leave a viscous solid. This solid was dissolved in 50 milliliters of ethyl acetate and the solution was washed with 30 milliliters of normal sodium hydroxide 1 and then with 30 milliliters of water. The organic layer was then dried over magnesium sulphate and concentrated in a 1 ’rotary evaporator at 55 ° C, so as to obtain a whitish-colored solid. The solid was recrystallized from a minimum quantity of a mixture of solvents consisting of ethyl acetate and ligroin (25:75 vol / vol), so as to collect a white powder (3.1 g, yield 73 %) consisting of (2 ', 4 * -dichlorophenoxy) -2-nitrobenzoylJ7 isopropyl glycinate with a molecular weight of 426, as determined by mass spectrography with fragments at 426, 307 and 310 and a dot melting at 99 -100 ° C *

EXAMPLE V

N - / "~ 5- (2 ′ -chloro-4’ -trif luoromethylphenoxy) -2-ethyl nitrobenzoyl_ glycinate

The procedure described in Example I was repeated, except that an equivalent amount of 5- (2'-chloro-4'-trifluoromethylphenoxy) -2-nitro-benzoyl chloride was used instead of chloride of 5- (2 ', 4'-dichlorophenoxy) - 2-nitrobenzoyl, so as to obtain ethyl N- / 5- (2'-chloro- -12- 4'-trifluoromethylphenoxy) -2-nitrobenzoyl_7glycinate.

EXAMPLE VI

N - / "” 5- (2 '-chloro-4' -trifluoromethylphenoxy) -2-nltrooenzoyl_7 ethyl alaninate__

1.4 g (0.012 mole) were introduced into a three-necked flask, containing 100 milliliters, equipped with an addition funnel, a reflux condenser and a magnetic stir bar. ) ethyl ester of alanine and 1.1 g (0.01 mole) of triethylamine in 30 milliliters of benzene. To the stirred solution and at room temperature (approximately 20 ° C), 3.79 g (0.01 mole) of 5- (2 '-chloro-4' -trif luor chloride) was added dropwise. adorned thylphenoxy) -2-nitrobenzoyl in 20 milliliters of benzene. The reaction was found to be exothermic. After the addition was complete, the mixture was brought to reflux for 6 hours, cooled and then transferred to a separatory funnel. It was then washed separately with 30 milliliters of normal hydrochloric acid 1, water, normal sodium hydroxide 1 and water, respectively. The organic phase was then dried over anhydrous magnesium sulfate and concentrated in a rotary evaporator at 55 ° C, so as to leave 3.8 g of a light yellow oil, consisting of N - / 5- (2'-chloro-4'-tr if luoromethylphenoxy) -2-nitrobenzoyl_7 ethyl alaninate, having an NMR spectrum (acetone, dg) 7.1-8.3δ (multiplet, 7H); 4.550 (quartet, 1H); 4.15 (2H quartet) The yellow oil crystallized on standing, and the crystals had a melting point of 98-100 ° C.

EXAMPLE VII

N - / “2 * -chloro-4 * -trif luoromethylphenoxy) -2-ethyl nitrobenzoyl_7- * ethyl 3-aminopropionate

1.4 g (0.012 mole) were introduced into a 3-necked flask, containing 100 milliliters, equipped with an addition funnel, a reflux condenser and a magnetic stir bar. ) ethyl ester of ß-alanine and 1.1 g (0.01 mole) of triethylamine in 30 milliliters of benzene. To the stirred solution at room temperature (approximately 20 ° C), 3.79 g (0.01 mole) of 2 * -chloro-4'-trizluoromethylphenoxy-2-nitrobenzoyl chloride was added dropwise. in 20 milliliters of benzene. The reaction was found to be exothermic. After the addition was complete, the mixture was heated to reflux for 6 hours, cooled and then transferred to a separator funnel. It was then washed separately with 30 milliliters of normal hydrochloric acid 1, 30 milliliters of water, 30 milliliters of normal sodium hydroxide 1 and 30 milliliters of water respectively. The organic phase was then dried over sulfate anhydrous magnesium and it was then concentrated on a rotary evaporator at 55 ° C, so as to leave 3.7 g of a clear yellow oil consisting of N - / "" 5- (2 '-chloro-4 '-trifluoromethylphenoxy) -2-ethyl nitrobenzoyl_7-3-aminopropionate having a spectrum of i -14- RM (acetone, dg) 7.1-8.2 δ (multiplet, 7H); 4.0 δ (quartet, 2H); 4.56 (quartet, 2H); 3.62 δ (triplet, 2H); 1.28 6 (triplet, 3H).

EXAMPLE VIII

N- / 5- (2 ’-chloro-41 -trifluoromethylphenoxy) -2-nitrotienzoyl_7 sec-butyl glycinate _________

The glycinate prepared in Example V was hydrolyzed

and it was esterified by implementing the process described in Example III, so as to obtain N - / "~ 5- (2 * -chloro-4 '-trifluoromethylphenoxy) -2-nitrobenzoyl_7 glycinate sec-butyl .

EXAMPLE IX

N- / ~ 5 (2 '-4-chloro-trifluoromethylphenoxy) -2-nitrobenzoyl_7 isopronyl glycinate_

The glycinate prepared in Example V was hydrolyzed and esterified with isopropyl alcohol using the procedure described in Example III, * so as to obtain the N - / ”* 5- (2 * -chloro-4'-trifluoromethyl phenoxy) -2-nitrobenzoyl_7 isopropyl glycinate.

Although the mode of synthesis of the compounds according to the invention has been illustrated with a certain detail in Examples I to IX above, it should be understood that any compound according to the present invention can be prepared by skilled in the art simply by varying the starting materials and using the techniques illustrated, or alternatively by employing other suitable techniques.

It has been found that the compounds according to the invention are effective in regulating the growth of a whole series of undesirable plants, that is to say weeds, when they are applied in a quantity herbicidally effective, in the growing medium before weeds emerge or on weeds after their emergence from the growing medium. The term "herbicidally effective amount" * refers to the amount of compound or mixture of compounds necessary to harm or damage the weeds to the extent that the weeds are unable to recover after application. '' a particular compound or a particular mixture of compounds applied in order to obtain a satisfactory herbicidal effect can vary within wide limits and depends on a whole series of factors, for example the resistance of a species of weed per particular , extent of infestation, climatic conditions, soil condition, method of application and the like. Typically, 0.224 to 11.2 kg of compound or mixture of compounds per hectare can be Obviously, the effectiveness of a particular compound against a particular species of weed can be readily determined by a relatively direct field or laboratory test, in a well known manner. of technical specialists.

Compounds in accordance with the invention may be used as such or in combination with acceptable agronomic adjuvants, inert vehicles, other herbicides, or other compounds commonly used in agriculture, for example pesticides, stabilizers for security guards, fertilizers and the like. The compounds according to the invention, whether or not combined with other materials acceptable from the agronomic point of view, are typically applied in the form of dust, granules, wettable powders, solutions, suspensions, d aerosols, emulsions, dispersions and the like, as are well known to those skilled in the art. When combined with other agronomically acceptable and typically used materials, the amount of the compound (s) according to the invention, which is present in the combination, can vary between wide limits -, * for example around 0, 05 to about 95 percent by weight of the composition. Typically, such compositions contain from about 5 to about 75 percent by weight of the compound (s) according to the invention.

It has been found that the compounds according to the invention are effective in destroying a whole series of broad-leaved and grassy weeds, at an application rate of 2.24 kg per hectare or less still, before or after the emergence of weeds, without endot mager notably desirable food crops, such as, for example, corn, wheat, rice and soybeans. Examples of weeds which can be effectively destroyed by the application of the compounds of the invention include the following weeds: Brassica kaber, Setaria glauca, Digitaria san-guinalis, Seshania spp. , Abutilon tïieophrasti, Sorghum -17- halepense, Echinochloa crusgalli, Datura stramonium,

Sida spinosa, Ipomoegfeurpurea (Roth) and the like.

Some of the compounds prepared in accordance with the procedures described in Examples I to IX were tested for their herbicidal activity against certain weed species under controlled laboratory, light, temperature and humidity conditions. Selected weed seeds were planted in flower beds. For pre-emergence tests, the beds were treated with the chosen compound immediately after planting. For post-emergence tests, the beds were treated with the chosen compound: after a germination period of two weeks. The compound was applied to the beds by spraying a solution of the compound in a solvent at the indicated application rate, the growth state of the weeds was observed and the toxic effect of the compound was evaluated periodically after its application. Summarized below in the form of a table, the weed species (identified by their Latin name), the compound applied (identified by reference to the examples in accordance with which it has been prepared) to weeds, the rate of application of the compound ( in kilos per hectare), as well as the form of application (pre- and post-emergence).

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Compound weed j i I i j

I V! VI: VI 1 VII: VII

_IF_ !

Sorghum halepense X I X X X X

'j î ““ r

Datura stramonium X j X X X X X

<

Brassica äaber X X j X j X X

, i! j |

Schinochloa crusgalli X Xi! X

ί! i | !

Sesbania spp. X X X X X i X

___; _ 1 | _ j i

Abutilon theophrasti X j X X. X X X

;

Ipomoea purpurea (Roth) X X X X

Setaria glauca j X j X | X X

_1_ i_i_ l t

Digitaria sanguinalis X | X X

AIDS spinosa j X | X X X

j__i_i_ _

Xanthium pennsylvanicum X

I I i i ~ 1 i! 11.2 | 2.24 2.24 2.24 2.24! __ | j | -émergence_j Pré j Pré j Post .Pré .Post Pré

In each of the above tests, it was observed that the various weed species were all either killed or damaged beyond any possible recovery within 20-24 days of the application of the particular compound.

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Although the invention has been described in great detail and with reference to illustrative embodiments, it should be understood that the invention is not limited thereto, since the compounds and to the methods according to the invention numerous modifications and variants without departing from its scope and its spirit.

Claims (5)

3. Compounds according to claim 1, characterized in that R represents an alkyl group containing up to 4 carbon atoms. 4. Compounds according to claim 1, carac-_, 2 terized in that R represents an agro-nomically acceptable ionic species, chosen from alkali metals, alkaline earth metals, ammonium and its derivatives dT * alkyl-ammonium and alkanol ammonium having 1 to 4 carbon atoms. 5 · - Compounds according to claim 1, characterized in that Z represents a nitro or cyano radical. 6. Compounds according to claim 1, chosen from the following substances: ethyl N- / 5- (2 ′, 4, -dichlorophenoxy) -2-nitrobenzoyl_7glycinate; N - / - ethyl 5- (2’-chloro-4’-trifluoromethylphenoxy) - 2-nitrobenzoyl_7 glycinate; N- / ~ 5- (2 ’, 4 * -dichlo-r rophenoxy) -2-nitrobenzoyl_7glycine; N- / ~ 5- (2’-dichloro-4’-trifluoromethylphenoxy) -2-nitrobenzoyl_7glycine; N- / 5- (2’-chloro-4 ’-trif luoromethylphenoxy) -2-nitroben-zoyl_ / isopropyl glycinate; Methyl N- / 5- (2’-chloro-4’-trifluoromethylphenoxy) -2-nitrobenzoyl_7glyGiriate; N- / 5- (2’-chloro-4’-trifluoromethylphenoxy) -2-nitrobenzoyl__7 sec-butyl glycinate; N- / 5- (2'-chloro-4 '-trif luoromé thylphenoxy) -2-nitrobenzoyl__7 ethyl alaninate and Ν-Γ5- (2' -chloro-4 '-trifluoromethylphenoxy) - 2-nitrobenzoyl ^ 7-3- ethyl aminopropionate. 7. Herbicidal compositions, characterized in that they contain a herbicidally effective amount of a compound or mixture of compounds according to any one of the preceding claims. 8. A process for combating the growth of weeds, characterized in that a herbicide-effective amount of a compound or a mixture of compounds according to any one of Claims 1 to 6 is applied. in the growth medium of the weeds before or after their emergence from the environment in question. Y