DE2833274C2 - - Google Patents

Description

The invention relates to those specified in claim 1 Imidazolinylbenzoates, which are specified in claims 24 and 27 A process for their preparation, that specified in claim 20 herbicidal compositions and those specified in claim 28 Imidazolinylbenzamide, the method specified in claim 38 for their preparation and the herbicidal specified in claim 35 Medium.  

Those imidazolinyl benzoates of formula I given in claim 1, wherein R₃ is not stands for hydrogen, can be produced by one Imidazoisoindoldione of formula II given later with a corresponding alkali metal alkoxide. The implementation will preferably carried out under inert gas protection at 20 to 50 ° C. Generally, you first mix an alkali metal  or an alkali metal hydride with a corresponding alcohol and then mixes the mixture obtained thereafter the respective imidazoisoindoldione of formula II.

In the above process, nitrogen, Use argon or helium, with nitrogen being preferred.

Examples of alkali metals or alkali metal hydrides that can be used are sodium, sodium hydride, potassium, potassium hydride, Lithium or lithium hydride.

The formulas above can be explained as follows:

Herein X, R₁, R₂ and R₃ have the meanings given in Claim 1.

In the above reactions, the alcohol acts both as a reactant as well as a solvent. You don't need a second one Solvent. However, one is used in the implementation expensive alcohol or you need to achieve optimal reaction conditions a large excess of alcohol, then recommends the addition of a cheaper second solvent to Reaction mixture such as dioxane, tetrahydrofuran or another non-protic solvent. The amount of that Non-protic solvent to be added to the reaction mixture can be varied quite widely. It generally goes  however not more than four times the amount of alcohol used out. The ratio of second solvent and alcohol, which can be used according to the invention therefore between 0.0: 1 and 4.0: 1.

Those compounds of formula I in which R₃ is hydrogen are made by using an imidazoisoindoldione of the formula II with an excess of hydrochloric acid in Presence of a water-miscible solvent such as tetrahydrofuran or dioxane. This implementation leads to one Lactone hydrochloride of the formula VI mentioned below, from which one can be treated with an equivalent base, such as Sodium hydroxide, potassium hydroxide or sodium carbonate, the receives appropriate acid. The implementation runs according to the formula as follows:

The compounds of formula I above can be mixtures of two positional isomers if X has a different meaning than hydrogen because they are used as intermediates Imidazoisoindoldiones of formula II also isomer mixtures if X is not hydrogen. The starting products of the formula II can be prepared by a corresponding phthalimidocarboxamide cyclized. The cyclization can be on one of the two imide carbonyl groups occur, resulting in a mixture of isomers if X is a has a different meaning than hydrogen:

and

The substituents R₁, R₂ and X therein have the above Meanings, except that X is not hydrogen can.

The imidazolinyl benzoates of formula I above can also be tautomeric. For the sake of simplicity, they are by one individual structure with the formula I, but can occur in one of the following two isomeric forms:

The substituents X, R₁, R₂ and R₃ have the above indicated meanings. Therefore under the formula I also understood both isomeric forms of imidazolinyl benzoates.

The connections are amphoteric. They both dissolve in acidic as well as in basic aqueous solutions, whereby when treated with strong acids, especially strong ones Mineral acid such as hydrochloric acid, sulfuric acid or Hydrobromic acid, the acid addition salts of imidazolinyl benzoates of formula I form.

Mean the substituents in the imidazolinyl benzoates of the formula I. R₁ and R₂ are different groups, then the carbon atom, to which these groups are bound, an asymmetrical one Carbon atom. Such connections come from (just as like their intermediates) in d- and l-forms as well as in dl forms.  

This is used to produce the respective d or l shape respective optically active d- or l-imidazoisoindoldione the Formula II with the corresponding alcohol of formula VII, thereby giving the corresponding d- or l-imidazolinyl benzoate Formula I arrives.

The imidazoisoindoldiones of formula II are intermediates for the preparation of the imidazolinyl benzoates according to the invention and are described in US-PS 40 17 510.  

The imidazolinylbenzamides of the formula III specified in claim 28 are indeed those mentioned Structural formula III, but you can again be tautomeric. You can also use the structure

have, wherein R₁, R₂, R₃ and R₄ have the meanings given in claim 28 have. Both tautomeric forms should therefore be present can be understood if of compounds of the structural formula III is spoken.

The imidazolinyl benzamides of the formula III

wherein R₁, R₂, R₃ and R₄ have the meanings given above, can be made by using an imidazoisoindoldione Formula V

wherein R₁ and R₂ have the meanings given above, with an amine of formula IV

R₄R₃NH, (IV)

wherein R₃ and R₄ have the meanings given above, implements.

The molar ratio of amine IV to imidazoisoindoldione V should be between 1: 1 and 10: 1, preferably 2: 1 and 5: 1. The reaction is preferably carried out in a non-protic solvent, such as tetrahydrofuran, dioxane, toluene, xylene or Benzene, carried out at temperatures between 50 and 100 ° C.

If the substituents R₁ and R₂ are different from one another, then represents the carbon atom to which the substituents R₁ and R₂ are bound, an asymmetry center, so that these compounds (as well as their intermediates) as d- and l-forms as well as dl forms. Is the respective imidazoisoindoldione Formula V optically active and you either set the d- or l-isomer thereof with an amine of the formula IV, namely with a compound of formula R₄R₃NH, um, then you get the corresponding d- or l-imidazolinylbenzamide of formula III.

The imidazoisoindoldiones of formula V used as intermediates for the preparation of the imidazolinylbenzamides of the formula III are required are described in DE-OS 27 00 270.

The preparation of the imidazolinyl benzamides of the formula III runs as follows:  

Here R₁, R₂, R₃ and R₄ have the meanings given above.

Examples of imidazolinylbenzamides according to the invention Formula III are as follows: o- (5-isopropyl-5-methyl-4-oxo-2-imidazolin-2-yl) -3-butynylbenzamide, o- (5,5-diethyl-4-oxo-2-imidazolin-2-yl) -N, N-diethylbenzamide, o- (5-isopropyl-5-methyl-4-oxo-2-imidazolin-2-yl) -N-2-butenylbenzamide-, o- (5-isopropyl-5-methyl-4-oxo-2-imidazolin-2-yl) -N-methylbenzamide, o- (5-isopropyl-5-methyl-4-oxo-2-imidazolin-2-yl) -N-isopropylbenzamide-, o- (5-isopropyl-5-methyl-4-oxo-2-imidazolin-2-yl) -N-allylbenzamide, o- (5-isopropyl-5-methyl-4-oxo-2-imidazolin-2-yl) -N, N-diallylbenzamide-,  o- (5-isopropyl-5-methyl-4-oxo-2-imidazolin-2-yl) -N-1,1- dimethyl-2-propynylbenzamide, o- (5-n-propyl-5-methyl-4-oxo-2-imidazolin-2-yl) -N-1- dimethylallylbenzamide, o- (5-isopropyl-5-methyl-4-oxo-2-imidazolin-2-yl) -N, N-diphenylbenzami-d, o- (5-cyclohexyl-5-methyl-4-oxo-2-imidazolin-2-yl) -N-2- propynylbenzamide, o- (5-benzyl-5-methyl-4-oxo-2-imidazolin-2-yl) -N, N-diisopropylbenzami-d, o- (5-isopropyl-5-methyl-4-oxo-2-imidazolin-2-yl) -N-benzylbenzamide or o- (4-Oxo-1,3-diazospiro [4,5] dec-2-en-2-yl) -N-n-propylbenzamide.

Preferred compounds of formula III are those in which R₂ for isopropyl stands.

The compounds according to the invention are extremely effective herbicides Agents for controlling monocotyledonous plants, Sedge grasses (Cyperacae) and dicotyledonous plants. they can be used to combat undesirable plant species can be used by looking at the foliage of such plants with a herbicidally effective amount of such compounds treated. They can also be used to combat pre-emergence unwanted plants by laying on the ground,  the seeds, seedlings or reproductive organs of the unwanted Plants contains a herbicidally effective amount of each Active ingredient applies. Since the imidazolinyl benzoates according to the invention of formula I are soluble to a very limited extent in water, they are generally called wettable powders, emulsifiable Formulated concentrates or flowable liquids, which you then normally spray in water or a other inexpensive liquid diluent dispersed. The compounds of the invention can also are formulated as granules, which are generally about Contain 10 to 15 percent by weight of active ingredient.

To produce a wettable powder, for example, one mixes about 25 to 80 percent by weight of the respective imidazolinyl benzoate, about 2 to 5 weight percent of a surfactant Agents such as sodium N-methyl-N-oleyltautrate, alkylphenoxypolyoxyethyleneethanol or sodium alkylnaphthalenesulfonate, 5 to 10 percent by weight of a dispersant such as highly purified Sodium lignosulfonate, and 25 to 63 weight percent of one finely divided carriers, such as kaolin, attapugite or diatomaceous earth, together.

A typical formulation produced in the above manner sets is composed as follows:

50 percent by weight 2-propynyl-o- (5-isopropyl-5-methyl-4-oxo 2-imidazolin-2-yl) benzoate, 3 percent by weight sodium N-methyl N-oleoyl autrate, 10% by weight sodium lignosulfonate and 37 percent by weight kaolin.

Flowable liquid formulations can be produced by using about 40 to 60 weight percent of an imidazolinyl benzoate of the formula I, 2 to 3 percent by weight of the sodium salt of condensed naphthalenesulfonic acid, 2 to 3 percent by weight  a gel-forming clay, 2 percent by weight propylene glycol and 54 to 32 weight percent water ground together.

Dissolves or disperses to produce a suitable granulate the respective active ingredient in a solvent and then brings the active ingredient to a sorptive or non-absorbent carriers such as attapulgite, corn on the cob, Pumice stone or talc.

As stated above, the imidazolinyl compounds of the formula I are effective pre-emergence herbicides. They are suitable for fighting broad-leaved weeds and grasses, if you can Soil that has broad-leaved seeds, seedlings, or reproductive organs Contains weeds, sedge grass or grass plants, treated with amounts of active ingredient from 0.07 to 11.2 kg / ha.

The compounds of the invention are also suitable to control broad-leaved weeds, sedge grasses and Grass plants if you take the foliage of such plants with Treated drug amounts of about 0.28 to 11.2 kg / ha.

With the compounds of the invention, the Combat different types of plants effectively, distinguish them differs from the known herbicides in that they are particularly good at fighting certain cyperaceas, especially reed grasses, in relatively low application concentrations let insert. The connections of the Formula I have therefore in practice for pre-emergence treatments in amounts of active ingredient from 0.14 to 11.2 kg / ha as special proven means to control reed grasses. Of course, can be used to control sedge grass and other annual plants also with higher application quantities of the compounds of formula I are worked when the stock is particularly strong on cyperaceas or annual plants.  

The imidazolinyl benzoates can be used under such conditions of formula I for pre-emergence treatment or for post-emergence treatment Apply in quantities of up to 25 kg / ha.

To cyperaceas that deal with the imidazolinyl derivatives according to the invention to fight, belong to purple cyber grass (Cyperus rotundus L.), yellow cyper grass (Cyperus esulentus L.), false cyper grass (Cyperus strigosus) and the flat sedge, Umbrella plants and Kyllinga.

The invention is further illustrated by the following examples explained.

Example 1 2-propynyl-o- (5-isopropyl-5-methyl-4-oxo-2-imidazolin-2-yl) - benzoate

12.5 ml of propargyl alcohol are added to 0.1 g of a 50 percent Suspension of sodium hydride in mineral oil. The addition is made under nitrogen protection, while stirring the reaction mixture and keeps it at 20 to 25 ° C by external cooling. After about 1 to 2 hours is the formation of the sodium salt of propargyl alcohol completed. The solution is then treated with 5.0 g of 3-isopropyl 3-methyl-5H-imidazo [2,1-a] isoindole-2 (3H), 5-dione added and the reaction mixture overnight under nitrogen protection stirred at room temperature. A subsequent thin layer chromatography Investigation shows that implementation is incomplete, and the reaction mixture is therefore with another 50 mg of a 50 percent suspension of sodium hydride mixed with mineral oil. The reaction mixture is over Stirred overnight, whereupon it is cooled to 5 ° C. and with 0.7 ml 3 normal hydrochloric acid added. Then diluted washing the reaction mixture with methylene chloride, the whole with water, dries the organic layer and narrows it down  Vacuum on. The resulting crystalline residue is transferred with hexane into a filter funnel and in the air dried, whereby 6.02 g of 2-propynyl-o- (5-isopropyl- 5-methyl-4-oxo-2-imidazolin-2-yl) benzoate, which at 131 to 144 ° C melts. By recrystallizing this material from acetone-hexane you get a pure product, that melts at 145 to 147 ° C.

Example 2 Preparation of imidazolinyl benzoates

According to the method described in Example 1 following imidazolinyl benzoates prepared by instead of propargyl alcohol, the specified alcohol used and instead of 3-isopropyl-3-methyl-5H-imidazo [2,1-a] - isoindole-2 (3H) -5-dione the respective imidazoisoindoldione starts. The implementation proceeds as follows:

Example 3 1,1-dimethylallyl-o- (5-isopropyl-5-methyl-4-oxo-2-imidazoline- 2-yl) benzoate hydrochloride

A solution of 164 mg 1,1-dimethylallyl-o- (5-isopropyl-5- methyl 4-oxo-2-imidazolin-2-yl) benzoate (0.5 mM) in 5 ml methylene chloride and 5 ml of absolute ethanol becomes normal with 0.5 ml of 1.0 Hydrochloric acid added. The reaction mixture is concentrated under vacuum, whereupon the residue was washed with ether treated, the crystalline product obtained is filtered off with Ether washes and air dries. This way to 170 mg of the hydrochloride specified in the title, which at 259 to 262 ° C melts with decomposition. The melting point this salt and other salts depend on the rate of heating.  

Example 4 o- (5-isopropyl-5-methyl-4-oxo-2-imidazolin-2-yl) benzoic acid

A solution of 5 g of 3-isopropyl-3-methyl-5H-imidazo [2,1-a] isoindole 2 (3H), 5-dione in 15 ml of dioxane is stirred with a Mixture of 10 ml concentrated hydrochloric acid and 10 ml Water added. The reaction mixture is heated to boiling whereupon it is allowed to cool to room temperature. The resulting one crystalline solid is filtered off, with water as well Washed acetone and air dried. The filtrate is concentrated under vacuum, whereupon the resultant Solid washes with acetone and air-dried. On this gives a total of 4.5 g of the lactone hydrochloride Structure A given above, at 265 ° C with decomposition melts.  

A partial solution of the above hydrochloride (4.5 g) in 30 ml Water is stirred with a solution of 0.6 g of sodium hydroxide added to 10 ml of water. Within a few minutes creates a complete solution, and after about 15 minutes a solid separates from the solution. This solid is filtered off. The filtrate is concentrated in vacuo, whereupon the solid obtained is filtered off, with the first Solid combined, washed with water and air dried. In this way, 3.8 g of o- (5-isopropyl-5-methyl-4- oxo-2-imidazolin-2-yl) benzoic acid at 162 to 163 ° C melts. An analytically pure sample has a melting point from 163 to 165 ° C.

Example 5 o- (5-isopropyl-5-methyl-4-oxo-2-imidazolin-2-yl) benzoic acid

To prepare the corresponding sodium salt, one adds a partial solution of 2.58 g imidazolinyl acid in 10 ml water with stirring with 9.9 ml of 1 normal sodium hydroxide. After 1.5 The solution is concentrated under vacuum for hours and the remaining Water is then removed azeotropically with dioxane, causing the hygroscopic sodium salt is obtained, which at 184 melts up to 188 ° C.

The corresponding amine salts are simply prepared by reaction in methanol. For this purpose you move a partial solution of 5.0 g imidazolinyl acid in 15 ml methanol with stirring with 3.17 ml of triethylamine. After 0.75 hours a clear solution. The solution is concentrated and the remaining slurry diluted with hexane, filtered and dried. This way you get the triethylamine salt, that melts at 54 to 55 ° C. In a similar way also made the isopropylamine salt, which has a melting point from 92 to 98 ° C.  

Example 6 o- (5-isopropyl-5-methyl-4-oxo-2-imidazolin-2-yl) -N, N-dimethylbenzami-d

A cold solution of 180 g 3-isopropyl-3-methyl-5H-imidazo- [2,1-a] isoindole-2 (3H), 5-dione in 300 ml dry tetrahydrofuran 68 g of dimethylamine are added in a pressure vessel. The pressure vessel is closed and the mixture is stirred Heated to 50 ° C for 16 hours. After cooling the reaction mixture you transfer the contents of the vessel into a flask and then removes the solvent under vacuum. The the crystalline residue obtained in this way is suspended in ether, whereupon the suspension is filtered, the remaining Wash material with ether and air dry. In this way, 195 g of o- (5-isopropyl-5-methyl- 4-oxo-2-imidazolin-2-yl) -N, N-dimethylbenzamide, which at 144 melts up to 146 ° C. By recrystallizing this material an analytically pure sample is obtained from acetonitrile, the melts at 147 to 150 ° C.

Example 7 Preparation of imidazolinylbenzamides

According to the procedure described in Example 6, Use of the imidazo [2,1-a] isoindole-2 (3H), 5-dione and the respective amine instead of dimethylamine from the following Established further connections established.  

Example 8 Efficacy as post-emergence herbicides

The effectiveness of the compounds according to the invention as post-emergence herbicides is shown by the following studies where you have a bunch of monocotyledonous plants, Cyperacaen and dicotyledonous plants with the corresponding Active substances treated in mixtures of water  and acetone are dispersed. For the examinations seedlings of the respective plants in separate for about 2 weeks Cups grow. The active substances to be examined are in mixtures of 50 parts acetone and 50 parts water dispersed, each 0.5% surfactant based on polyoxyethylene sorbitan monolaurate contain and such an amount of active ingredient exhibit that when the corresponding active ingredient is applied Dispersions on the respective plants by means of one at a pressure of 2.8 kg / cm² above a predetermined one Time operated spray nozzle an amount of active ingredient of about 0.07 up to 11.2 kg per ha. After spraying, the Plants placed on hothouse tables and in the usual way further cherished. 2 weeks after treatment, the Seedling plants except the seedlings of the wind oat, which are only assessed after 5 weeks, accordingly checked and rated according to the following rating scale. The the data obtained here are from the tables below I and II.

Abbreviations of plants:

PN - Purple Cypergrass (Cyperus rotundus L.)
SE - Sesbania (Sesbania exaltata)
MU - Mustard (Brassica kaber)
PI - Field Foxtail (Amaranthus retroflexus)
RW - Ambrosia herb (Ambrosia artemisiifolia)
MG - Purple Bindweed (Ipomoea purpurea)
BA - Millet (Echinochloa crusgalli)
CR - Blood finger millet (Digitaria sanguinalis)
FO - Green Bristle Millet (Setaria viridis)
WHERE - wind oat (Avena fatua)
TW - Tea herb (Sida spinosa)
VL - Indian Mallow (Abutilon theophrasti)
CN - maize (Zea mays)
CO - Cotton (Gossypium hirsutum)
SY - Soybean (Glycine max)
RI - Rice (Oryza sativa)
JW - Common Datura (Datura stramonium L.)

Example 9 Efficacy as pre-emergence herbicides

The effectiveness of the compounds according to the invention as pre-emergence herbicides is shown by the following tests, for which seeds or reproductive organs of various monocotyledonous plants, cyperaceae and dicotyledonous plants are mixed separately with plant soil and the mixture thus obtained is then introduced into separate beakers on an approximately 2.5 cm high layer of soil . After planting, the cups are sprayed in such an amount with the respective solution of the active ingredient in mixtures of water and acetone that there is an amount of active ingredient of about 0.28 to 11.2 kg per hectare per cup. The treated cups are then placed on hothouse tables, watered and kept in the usual way. The investigations are stopped three or four weeks after the treatment has been carried out, each cup being checked accordingly and rated on the evaluation scale given in Example 8. The data obtained here are shown in Tables III and IV below.

Example 10 Efficacy as selective post-emergence herbicides

The effectiveness of the compounds according to the invention as selective post-emergence herbicides is shown by the following tests, in which sorghum plants [Sorghum bicolor (L) Woeuch], spring wheat plants (Triticum aestivum, cv. Auza) and barley plants (Hordeum vulgare, cv. Steptoe) with corresponding active ingredients treated, which are dispersed in mixtures of water and acetone. The procedure described in Example 8 is followed in detail, the treated plants being examined as indicated in Example 8 and evaluated on the assessment scale there. The results obtained in these experiments are shown in Table V below.

Example 11 Efficacy as selective pre-emergence herbicides

According to the method described in Example 9, the effectiveness of the compounds according to the invention as selective pre-emergence herbicides is investigated using sorghum plants [Sorghum bicolor (L) Moeuch], spring wheat plants (Triticum aestivum, cv. Auza) and barley plants (Hordeum vulgare, cv. Steptoe). The evaluation of the test results is carried out according to the evaluation scale given in Example 8. The results obtained in these experiments are shown in Table VI below.

Claims (39)

1. Imidazolinylbenzoates of the formula where X is hydrogen, methyl, chlorine or nitro,
R₁ is C₁-C₃ alkyl,
R₂ is C₁-C₃-alkyl or cyclohexyl or
the substituents R₁ and R₂ together with the carbon atom to which they are attached mean cyclohexyl or methylcyclohexyl,
R₃ is hydrogen, C₁-C₁₂-alkyl, which is optionally substituted with a C₁-C₃-alkoxy group, a C₃-Co-cycloalkyl group, a furyl group or 1 to 3 halogen atoms, C₃-C₅-alkenyl, which is optionally substituted with 1 or 2 C₁- C₃-alkyl groups, a phenyl group or 1 to 2 chlorine atoms is substituted, C₃-C₅-alkynyl, which is optionally substituted with 1 to 2 C₁-C₃-alkyl groups or a phenyl group, benzyl, cyclohexenylmethyl, ethynylcyclohexyl, ethinylallyl, pentadienyl or C₃-C₆ -Cycloalkyl, which is optionally substituted by 1 or 2 C₁-C₃-alkyl groups, or R₁ is methyl, R₂ isopropyl, X is hydrogen and R₃ is a radical of the formula -CH₂≡C-C₇H₁₅-n or -CH₂-C≡C- CH₂OH or to form a bis compound is a radical of the formula -CH₂-CH₂- and, if the substituents R₁ and R₂ are not the same, the optical isomers thereof and isomer mixtures thereof, and the acid addition salts of these compounds. 2. Compounds according to claim 1, characterized in that X is hydrogen, methyl or chlorine,
R₁ is methyl,
R₂ is isopropyl and
R₃ has the meaning given in claim 1. 3. 2- (5-isopropyl-5-methyl-4-oxo-2-imidazolin-2-yl) methyl benzoate. 4. 2- (5-isopropyl-5-methyl-4-oxo-2-imidazolin-2-yl) benzoin Acid 2-propinyl ester. 5. 2- (5-isopropyl-5-methyl-4-oxo-2-imidazolin-2-yl) benzoic acid.   6. mixture of isomers of 6- (5-isopropyl-5-methyl-4-oxo-2- imidazolin-2-yl) -m-toluic acid methyl ester and 2- (5-isopropyl- 5-methyl-4-oxo-2-imidazolin-2-yl-p-toluic acid methyl ester. 7. 2- (5-isopropyl-5-methyl-4-oxo-2-imidazolin-2-yl) benzoic acid m-propyl ester. 8. 2- (5-isopropyl-5-methyl-4-oxo-2-imidazolin-2-yl) benzoic acid - 1,1-dimethylallyl ester. 9. 2- (5-isopropyl-5-methyl-4-oxo-2-imidazolin-2-yl) allyl benzoate. 10. 2- (5-isopropyl-5-methyl-4-oxo-2-imidazolin-2-yl) octyl benzoate. 11. (+) - 2- (5-isopropyl-5-methyl-4-oxo-2-imidazolin-2-yl) - ethyl benzoate. 12. (+) - 2- (5-isopropyl-5-methyl-4-oxo-2-imidazolin-2-yl) - 2-chloroallyl benzoate. 13. 2- (5-ethyl-5-methyl-4-oxo-2-imidazolin-2-yl) benzoic acid.   14. Isomer mixture from 3-chloro-2- (5-isopropyl-5-methyl-4- oxo-2-imidazolin-2-yl) benzoic acid and 6-chloro-2- (5-isopropyl-5- methyl-4-oxo-2-imidazolin-2-yl) benzoic acid. 15. (-) - 2- (5-isopropyl-5-methyl-4-oxo-2-imidazolin-2-yl) - 2-propynyl benzoate. 16. 2- (5-isopropyl-5-methyl-4-oxo-2-imidazolin-2-yl) - benzoic acid isopropylamine salt. 17. mixture of isomers of 6- (5-isopropyl-5-methyl-4-oxo-2- imidazolin-2-yl) -m-toluic acid and 2- (5-isopropyl-5-methyl- 4-oxo-2-imidazolin-2-yl) -p-toluic acid. 18. 2- (5-isopropyl-5-methyl-4-oxo-2-imidazolin-2-yl) - benzoic acid sodium salt. 19. 2- (5-isopropyl-5-methyl-4-oxo-2-imidazolin-2-yl) benzoic acid 1-methyl-2-butenyl ester. 20. Herbicidal agent for controlling undesirable plant species from a herbicidally effective amount of a corresponding Active ingredient and optionally a conventional carrier or diluent, characterized, that it is a compound as claimed in one of the claims Contains 1 to 19.   21. Composition according to claim 20, characterized in that it's pre-emergence undesirable plant species in application amounts from 0.07 to 11.2 kg of active ingredient per hectare used to treat a soil the seed, seedlings or other reproductive organs which contains plants to be controlled. 22. Composition according to claim 20, characterized in that it is to combat Cyperacaen or other annual plants in application quantities from about 0.56 to 25 kg of active ingredient per hectare on one soil is applied, the seed or other reproductive system which contains cyperaceas or annual plants to be controlled. 23. Means according to claim 20 to combat post-emergence undesirable Plants, characterized, that it is in use amounts of about 0.28 to 25 kg of active ingredient per hectare on the foliage of the is applied to plants to be controlled. 24. A process for the preparation of imidazolinyl benzoates of the formula I from claim 1, in which R₃ is not hydrogen, characterized in that an imidazoisoindoldione of the formula II wherein X, R₁ and R₂ have the meanings given in claim 1, with an alcohol of the formula VIIR₃OH, (VII) wherein R₃ has the meaning given in claim 1, in the presence of an alkali metal or an alkali metal hydride at about 20 to 50 ° C. 25. The method according to claim 24, characterized in that with a ratio of Alcohol to imidazoisoindoldione from 1.1 to 1.0: 5.0 to 1.0 works and carries out the implementation under inert gas protection. 26. The method according to claim 24, characterized in that the reaction mixture from imidazoisoindoldione, alcohol and alkali metal or Alkali metal hydride with such an amount of a non-protic Solvent added that the ratio of non-protic Solvent to alcohol does not exceed 4: 1 and carries out the implementation under inert gas protection. 27. A process for the preparation of imidazolinyl acids of the formula I from claim 1, in which R₃ is hydrogen, characterized in that an imidazoisoindoldione of the formula II wherein X, R₁ and R₂ have the meanings given above, treated with excess hydrochloric acid in such a way that the corresponding lactone hydrochloride is formed, and this lactone hydrochloride is then reacted with one equivalent of a base to form the desired imidazolinyl acid. 28. Imidazolinylbenzamides of the formula III whereR₁ is methyl,
R₂ is C₁-C₃-alkyl, cyclohexyl or benzyl, or
the substituents R₁ and R₂ together with the carbon atoms to which they are attached mean cyclohexyl and
R₃ and R₄ are each individually hydrogen, C₁-C₃ alkyl, allyl, dimethylallyl, propynyl or benzyl, and, if the substituents R₁ and R₂ are not the same, the optical isomers thereof. 29. o- (5-isopropyl-5-methyl-4-oxo-2-imidazolin-2-yl) -N, N- dimethylbenzamide. 30. o- (5-isopropyl-5-methyl-4-oxo-2-imidazolin-2-yl) -N-2- propynylbenzamide. 31. o- (5-isopropyl-5-methyl-4-oxo-2-imidazolin-2-yl) -N- methylbenzamide. 32. o- (5-isopropyl-5-methyl-4-oxo-2-imidazolin-2-yl) benzamide.   33. N, N-dimethyl-o- (4-oxo-1,3-diazospiro [4,5] dec-2-en- 2-yl) benzamide. 34. N-methyl-o- (4-oxo-1,3-diazospiro [4,5] dec-2-en-2-yl) - benzamide. 35. Herbicidal agent for controlling undesirable broad-leaved Weeds and grasses from a herbicidally active Amount of a corresponding active ingredient and optionally one usual auxiliary or carrier means, characterized in that it is an active ingredient an imidazolidinylbenzamide according to any one of claims 27 to 34. 36. Herbicidal composition according to claim 35, characterized characterized in that it was in such quantity the foliage of the plants to be controlled is applied, that there are 0.28 to 11.2 kg of active ingredient per hectare. 37. Herbicidal composition according to claim 35, characterized characterized as being a pre-emergence agent to fight monocotyledonous plants, Cyperacaen or dicotyledonous plants on the ground in such quantity is applied to the seeds or seedlings of such plants contains that about 0.28 to 11.2 kg of active ingredient per hectare surrender. 38. A process for the preparation of imidazolinylbenzamides of the formula III from claim 28, characterized in that an imidazoisoindoldione of the formula V wherein R₁ and R₂ have the meanings given in claim 28, with an amine of the formula IVR₄R₃NH, (IV) in which R₃ and R₄ have the meanings given in claim 28, at elevated temperature between 50 and 100 ° C in the presence of a non-protic solvent. 39. The method according to claim 38, characterized in that one with a molar ratio of amine of formula IV to imidazoisoindoldione Formula V works from 1: 1 to 10: 1.