DE2511897C2 - 2,6-Dinitroanilines, processes for their preparation and herbicidal compositions containing them - Google Patents

Description

wherein R is an ethyl, propyl or allyl group.

2. Process for the preparation of the 2,6-Dinltroaniline according to claim 1, characterized in that one a dinitrobenzene of the general formula

X

O ₂ N 1 NO ₂

CF ₃

wherein X is a halogen atom, preferably a chlorine atom, with an amine of the general formula

CH ₃

I.
R-NH-CH ₂ -C = CH ₂ (III)

wherein R has the meaning given in claim 1, converts into catfish known per se.

3. Herbicidal agent characterized by the content of at least one compound according to claim 1 or 2 In a mixture with at least one inert carrier or diluent.

2,6-DinitroanIllne are in US-PS 32 57 190, DE-OS 21 61 879 and DE-OS 22 32 263 as herbicidal Means described.

The invention relates to the 2,6-dinitroanllines described in the claims, processes for their preparation and herbicidal compositions containing them.

The 2,6-Dinltroaniline invention are characterized by an N- (2-Methallylgruppe), which for the the above known 2,6-dinitroanaline herbicides is not described. It has been shown that the 2,6-Dinltroaniline according to the invention compared to the most important of the known representatives, the N, N-Di-npropyl-4-trlfluoromethyl-2,6-dtnitroaniline, distinguished by a surprising superiority. On incorporation of the 2,6-dinitroaniline derivative according to the invention of the formula I according to the claims, in which R is an ethyl group represents, in the soil of cotton fields, in an amount of 1 kg / ha, there was control of up to 8896 of the weed Solanum nigrum. With the comparison compound was under comparable conditions only a control of 54% possible.

The compounds according to the invention are thus distinguished by excellent selective herbicidal properties

Effectiveness off, d. H. they are phytotoxic to many classes of weeds, but diffuse to many ss ligen crops, such as /. B. Cotton, soybeans and other edible beans are common. Hence kflnncn ί the novel compounds according to the invention for selective weed control in such cultivated or

Crops are used.
To produce the herbal agents according to the invention, at least one compound of the formula I is used with

mixed with at least one suitable carrier or diluent therefor. For use to inhibit wi or preventing the growth of weeds and / or weed seeds or germs on arable land an effective amount of at least one compound of the

apply the general formula 1 to the arable land.
The synthesis of the compounds according to the invention is preferably carried out in an organic solvent

or carried out in a basic aqueous medium at a temperature of from 0 to about 100 ° C. or above. Depending on the reaction temperature, the reaction times are generally within the range of about 1 to about 24 hours. All as starting materials in the synthesis of the compounds of the invention The compounds used are commercially available or can be found in the chemical literature per se

known processes are produced.

Suitable organic solvents include aromatic hydrocarbons such as benzene and toluene, Alcohols such as ethanol and isopropanol and other inert reaction solvents such as tetrahydrofuran and Dimethyl sulfoxide. An acid binder such as triethylamine should be added to the organic solvent which binds (absorbs) the hydrogen halide released during the reaction (e.g. HCl). The implementation runs well in a basic aqueous medium; sodium carbonate is preferably used as the base is used, although other bases such as sodium hydroxide or potassium carbonate are also suitable.

The reaction temperature can be from 0 to about 100 ° C or even above if a high pressure device used can be varied. It is most convenient to run the reaction at the reflux temperature of the reaction mixture perform. Carrying out the reactions at elevated temperatures does not lead to any Side reactions or no thermal decomposition. in

In general, the reactions proceed at temperature-dependent rates to completion away. The reaction rate can be increased by using a high-boiling reaction solvent and increased by working at the reflux temperature. An hour is enough for a considerable one To achieve yield of each of the compounds according to the invention. Even at low temperatures 24 hours suffice to obtain a maximum yield of each of the compounds according to the invention. is

Preferred compounds according to the invention which are used for herbicidal agents are N-ethyl-N-methallyl-4-trifluoromethyl! -2,6-dinitroaniline, N • methallyl-N-propyM-trifluoromethyl-dinitroaniline and N-alryl-N-methallyl-4-trifluoromethyl-2,6-dinitroanil! N. The particularly preferred compound according to the invention is N-ethyl-N-methallyl ^ -trifluoromethyl ^ ö-dinitroaniline.

Manufacturing example:

This preparation example shows the reaction by which the compounds according to the invention are prepared based on the preparation of 4-trifluoromethyl-N-alkyK or N-alkcnyl) -N-mcihallyl-2,6-dinitroaniline explained:

A reaction mixture containing 4-chloro-3,5-dinltro-a, ar, a-benzotrifluoride, the appropriate N-alkyl (or N-alkenyDmethallylamine and triethylamine in 100 ml of benzene was below. Stir under reflux overnight cooked. After the completion of the reaction, the reaction mixture was first diluted with hydrochloric acid and then washed with water and the organic phase was dried over magnesium sulfate. That Solvent was then removed in vacuo and the oily residue dissolved in hexane and with chromatographed on a 100 g column filled with purified magnesium silicate. The purified product was eluted with hexane containing increasing amounts, up to 20%, of benzene. The fractions containing the product were collected and evaporated in vacuo to give the product.

The above preparation example represents a typical synthesis according to which the invention Connections can be made. It does not present any difficulties to the person skilled in the art, by minor ones Modification of the synthesis described above to produce all compounds according to the invention. The general procedure described in the Preparation Example was followed to prepare the ones described in FIGS Compounds listed below are used. The characteristic data for each connection are given in the following examples.

example 1
N-Allyl-N-methallyl ^ -trlfluoromethyl ^ o-dinitroaniline, m.p. 53 to 54 ° C

Example 2

N-ethyl-N-methallyM-trlfluoromethyl ^ o-dinltroaniline, m.p. 54 to 57 "C

Example 3

N-methallyl-N-propyl ^ -trifluoromethyl-l ^ -dinltroanilin, F. 41 to 43 ^C C

The herbicidal test method described below was used to evaluate the compounds according to the invention carried out:

The soil in which the test plants were grown was a mixture of the same Voluminous sand and medium-heavy humus. The plants were made in shallow galvanized dishes Steel drawn to a length of 35 cm, a width of 25 cm and a depth of 8 cm. The bottoms of the bowls were ribbed and perforated for drainage.

The test compound was prepared by dissolving 120 mg of the same in 2.5 ml of a 10 g emulsifier containing solution In a mixture of 1 liter of acetone and 1 liter of ethanol. The 2.5 ml solution was £> o then dispersed in 22.5 ml of water containing 0.045% emulsifier. The aqueous dispersion became more suitable Catfish diluted to produce formulations containing the correct amounts of the test compound when 12.5 ml of the dispersion was applied to each area.

3.79 liters of the mixing soil was applied to each surface and leveled. The seeds of each of the test plants became seeds Planted in the earth in rows perpendicular to the long axis of the plane and covered with earth. 0.47 liters of a liquid fertilizer containing 2.5 g of soluble fertilizer was added after planting each area added.

The compound to be tested was put through on the same day the seeds were planted

evenly spraying the compound dispersion onto the earth using an atomizing spray gun applied to the area.

After the treatment, the samples (areas) were placed in a greenhouse kept at a temperature and humidity suitable for the growth of the plants. The plants were observed 12 days after treatment and each of the plant species was rated using a 1-5 scale. Rating 1 indicates that the plants rose and grew normally, and rating 5 indicates that the plants did not rise or that the plants died after emergence. Ratings 2, 3 and 4 indicate weak, moderate and severe damage, respectively. The results observed after application of the compounds according to the invention to be examined in an amount of 0.454 to 1.81 kg per 4047 m ² are given in the table below. The compounds are designated therein by the number of the respective preparation examples given above. To avoid misunderstandings, the German names of the plants and the corresponding Latin names are compared below.

is corn Zea mays Connection I. wheat E. Weeds whiter
Goose feet a mustard it SBJ Hiifergra e IU zinnia Hem wool Gossypium hlrsutum brought up 1 3 alfalfa
Zuckerrl
rice
cucumber
tomato 3 great
Longer 2 Günselu Sf 3 Grleswu Ό
C. 2 Soybean Glycine max at of amount In 3 3 2 2 3 12 approx 4th 5 2 3 C3 4th 2 Splendor 1 wheat Triticum vulgar Belsp. 0.454 kg = 1 2 3 2 4 12 'S " 4th 5 1 4th 4th 3 1 1 alfalfa Medicago satlva per g
4047 m ² "ε
2 approx 3 5 13 4 11 5 5 3 4th Fox sc 5 1 2 2 2 »Sugar beet Beta vulgaris 1) 1 11 2 2 4 4 5 3 3 barn
(Chicken 4th 5 2 5 4th 4th 3 1 2 rice Oryza satlva 4 4 1 3 4th 2 3 4 3 2 4th 4th 5 3 4th 4th 4th 3 2 2 cucumber Cucumis sativus 2) 1 3 - 3 3 5 4 3 4th 5 4th 5 3 2 tomato Lycopersicon esculentum 4 4 - 5 5 2 Barnyard- Echinochlora crusgalli <n 3) 1 4 3 5 4th : ^; Grass (chicken millet) 4 4 1 4th 4th white goosefoot Chenopodium album 4th large fingergrass Digitaria sanguinalls mustard Brassla sp. Goosefoot Amaranthus retroflexus se foxtail grass Setaria sp. Oat grass Avena sp. Grleswurz Abutllon theophrasti Morning glory Ipomea sp. zinnia Zinnia sp. Cultivated plants or harvest plants

The compounds of the invention are most conveniently used in the context of those described below Herbicide treatment method used. They are methods of inhibiting growth of weeds and to prevent weed seeds from germinating in cultivated farmland. A herblzid effective amount of a compound according to the invention is used before the weeds emerge on the cultivated Farmland applied.

As can be seen from the data given above, the compounds according to the invention can be used safely many economically important crops or crops are used, with cotton, soybeans and sugar beets are particularly preferred. Other crops or crops in which the inventive Compounds can be used with advantage are, for. B. potatoes, tomatoes, tobacco, onions, Melons and cucumbers.

With the help of the compounds according to the invention, it is possible to remove many weeds which have those mentioned above and contaminate and damage other crops or crops, control (control), such as the above data show. With the help of certain of the compounds according to the invention, it is also possible fight other harmful weeds, such as B. Solanum nlgrum, Chenopodium album, Polygonum convolvulus, Datura stramonium, Portulaca oleracea, Convolvulus arvensis, Fumaria officlnalis, Echlnachloa crus-galli, Setaria sp., Poa annua and Phalaris minor.

In general, it is most convenient to practice herbicide treatment procedures in the catfish, ate the compounds before planting the crop seeds, but after the arable land has been prepared for implantation. Usually it's most effective to put the compound in incorporate the top layer of soil by mixing the soil with a tool, such as. B. a hoe, a roller cultivator or a disc harrow, after connecting to the arable land (cultivated field) has been applied. The incorporation device should cut the joint in about a two-inch to about six inches Mix in deep layer of soil.

Herbicidally effective amounts are generally within the range from about 0.11 to about 4.54 kg per 4047 m ² , the preferred application amount is within the range from about 0.23 to about 1.81 per 4047 m ² . However, amounts below or above the specified range may sometimes be required.

The compounds according to the invention and the herbicidal compositions according to the invention inhibit growth the seedlings of weeds and the emergence of weeds to an extent that depends on the respective Weed species and the applied compounds according to the invention and the amounts thereof depends. In In some cases, as indicated by the herbicidal test data given above, the entire weed population becomes killed In other cases only the rising weeds are damaged or some of the weeds are destroyed killed and a part is damaged. The damage to a weed seedling growing in the cultivated farmland is highly beneficial for the cultivated or harvested plant, because the normally growing cultivated or harvested plants Harvest plants displace the slowly growing weeds. This displacement effect of the culture resp. A crop plant is particularly significant in a bushy crop or crop plant, such as cotton or a those from the bean family.

Although the compounds of the invention can be applied neat to the cultivated arable land, it is much more convenient and convenient to apply one of the herbicidal compositions of the invention. The herbicidal compositions according to the invention contain one or more of the compounds according to the invention in combination with at least one inert carrier. The inert carriers can be liquid or solid. Inert carriers which are included in the herbicidal compositions, and the process for preparing the herbivorous ² ^ ziden agent may be those, as they are commonly used in agriculture. To illustrate the best processes, however, the preparation of the herbicidal compositions according to the invention is described with the aid of a few examples.

The compounds according to the invention are very often in the form of concentrated herbicidal agents, those in the form of aqueous dispersions or emulsions containing about 0.1 to about 196 of the compound, to be applied to the earth. In the case of the water-dispersible or emulsifiable herbicidal agents it is either finely divided solids, usually known as wettable powders, or Liquids usually known as emulsifiable concentrates.

Herbicidal wettable powders consist of an intimate mixture of the active compound, an inert carrier and surfactants. The concentration of the active compound is typically from about ^10-15 to about 90%. The inert carrier is generally chosen from attapulgite clays, montmorillonite clays, diatomaceous earths and purified silicates. Effective surfactants, which constitute from about 0.5 to about 10 percent of the wettable powder, are found among the sulfonated lignins, the condensed naphthalene sulfonates, the naphthalene sulfonates, the alkylbenzenesulfonates, the alkyl sulfates and the nonionic surfactants such as ethylene oxide adducts of phenol. ■ «)

Typical herbicidal emulsifiable concentrates of the compounds according to the invention contain a suitable one Concentration of the active compound, e.g. B. about 0.23 to about 2.72 kg per 3.79 l of liquid dissolved in a inert carrier, which is a mixture of a water-immiscible organic Solvents and emulsifiers. The organic solvent is in terms of its solvency and selected its cost. Suitable organic solvents include the aromatics, in particular the xylenes, the petroleum fractions, especially the high-boiling naphthalene and olefinic ones Proportions of petroleum, such as heavy aromatic naphtha. Other organic solvents can also be used can be used, such as B. the terpene solvents, e.g. B. Rosin derivatives. The emulsifiers are about 0.5 to Making up about 10% of emulsifiable concentrates are made up of the same types of surfactants Agents such as those used for wettable powders are selected. so

Suitable forms are also granular herbicidal agents, in which the compounds are simply uniform Spread the herbicidal agent over the cultivated farmland. The herbicidal granules usually contain a compound distributed on a granular inert carrier, which is in the Usually it is roughly ground clay. The particle size of these granules is generally within the Range from about 0.1 to about 3 mm. The usual manufacturing process is that you make the connection in a solvent such as kerosene or a heavy aromatic naphtha, and dissolve the solution in applies to the carrier using a suitable mixer. A less economical method is that the compound is spread in a dough consisting of a damp clay or other carrier, which is then dried and coarsely ground to form the desired granular product.

The herbicidal compositions according to the invention can be applied to the ^ω cultivated arable land using a conventional apparatus.

Claims (1)

Claims: 1. 2,6-Dinltroaniline, the general formula CH _{3 R} - _N -C "i = CH, I (D ίο O ₂ N- f \ - NO ₂