JP2648340B2 - 6-chlorobenzoxazolyl-oxyacetanilide - Google Patents

Description

The present invention relates to a novel 6-chlorobenzoxazolyl-oxyacetanilide, a process for its preparation and its use as a herbicide.

It is known that certain 6-chlorobenzoxazolyl-oxyacetamides have herbicidal properties; however, because their tolerance is very low for certain crops, such as rice, these active compounds are It cannot be used as a selective herbicide for such crops (DE-OS DE)
-A 3,418,168; and EP-EP-
A No. 161,602).

The following formula (I) Wherein R represents straight-chain or branched alkyl having 1 to 6 carbon atoms, and n represents the number 0, 1 or 2, and the novel 6-chlorobenzoxazolyl-oxyacetanilide of Was issued. However, R represents CH _3, either n is 0 or 1 with a CH ₃ in the 2-position two compounds of formula (I), that compound 2- (6-chloro-benzoxazole sol - 2-yl) -N-methyl-oxyacetanilide and 2- (6-chlorobenzoxazol-2)
-Yl) -N-methyl-oxyaceto- (2-methylanilide) is excluded.

Furthermore, the novel 6-chlorobenzoxazolyl of the formula (I)
Oxyacetanilide has the formula (II) Where X is an electron-withdrawing group.
6-chlorobenzoxazole of the formula (III) Wherein R and n have the above-mentioned meanings, and can be obtained by a method of reacting with glycolic anilide of the following formula, optionally in the presence of a diluent, and optionally in the presence of an acid binder, and optionally in the presence of a catalyst. Was found.

Finally, it has been found that the novel 6-chlorobenzoxazolyl-oxyacetanilides of the formula (I) have good herbicidal properties, in particular selective herbicidal properties. Surprisingly,
The novel active compounds have excellent activity against rice weeds and exhibit remarkable selectivity in rice cultivation. In this regard, the novel active compounds are clearly superior to most similar compounds known from the prior art.

Suitable active compounds of the formula (I) are the compounds mentioned in the examples; 2- (6-chloro-benzoxazol-2-yl) -N-methoxy-oxyaceto- according to example 1.
(2,3-Dimethylanilide) is particularly preferred.

For example, if 2,6-dichlorobenzoxazole and N-methyl-cholic acid- (2,3-dimethylanilide)
If is used as a starting material, the route of the reaction according to the invention can be represented by the following formula: Formula (II) gives a general definition of 6-chlorobenzoxazole, which is required as a starting material for carrying out the process according to the invention. In this formula (II), X preferably represents halogen, in particular chlorine or bromine, or (C ₁ -C ₄ )
-Alkylsulfonyl or phenyl- (C ₁ -C ₂ ) -alkylsulfonyl, in particular methylsulfonyl, ethylsulfonyl or benzylsulfonyl.

6-Chlorobenzoxazole is known (eg EP-A 43,573 or German patent DE-A).
No. 3,025,910) or simply in a similar manner according to methods known in principle.

Glycol anilides of the formula (III), which are also necessary as starting materials for carrying out the process according to the invention, are likewise known (eg DE-A 2,904,490).
No., European Patent EP-A 5,501, European Patent E
No. PA-29,171, DE-A-3,038,598 and DE-A-3,244,956).

Diluents that can be used in the method of the present invention are organic or inorganic solvents. Suitable diluents are hydrocarbons such as toluene or cyclohexane; methylene chloride, chloroform,
Halogenated hydrocarbons such as dichloroethane or chlorobenzene; ketones such as acetone or methyl isobutyl ketone; ethers such as diethyl ether, diisopropyl ether or methyl tert-butyl ether; alcohols such as methanol, ethanol or isopropanol; dimethylformamide or dimethyl Amides such as acetamide; sulfoxides such as dimethyl sulfoxide; and even water or aqueous solutions of salts.

Salts preferably used in the present process are chlorides or sulphates of alkali metals or alkaline earth metals such as, for example, sodium chloride, potassium chloride or calcium chloride.
Sodium chloride is particularly preferred.

The process according to the invention is advantageously carried out by using an acid binder. Acid binders which are preferably used are compounds of strongly basic alkali metals or alkaline earth metals, for example oxides such as sodium oxide, potassium oxide, magnesium oxide and calcium oxide, sodium hydroxide, potassium hydroxide, Hydroxides such as magnesium hydroxide and calcium hydroxide, and / or carbonates such as sodium carbonate, potassium carbonate, magnesium carbonate and calcium carbonate.

0.01 to 10% by weight (based on the glycolic anilide of the formula (III) used) of a phase transfer catalyst (ph
The addition of ose transfer catalyst has been found to be advantageous in some cases. Examples of such catalysts are:
Tetrabutylammonium chloride, tetrabutylammonium bromide, bromide tributyl - methyl phosphonium chloride trimethyl -C ₁₃ / C ₁₅ - alkyl - ammonium, tetrabutyl ammonium hydroxide, 18-crown -
6, triethylbenzylammonium chloride, trimethylbenzylammonium chloride and tetraethylammonium bromide.

In the process according to the invention, the reaction temperatures can be varied over a fairly wide range. Reaction temperature is generally -50 ° C
And -100 ° C, preferably between -20 ° C and + 100 ° C.

The reaction according to the invention is generally carried out under normal pressure, but can also be carried out under elevated or reduced pressure, for example between 0.1 and 10 bar.

In carrying out the process according to the invention, the o-
In general, 0.1 to 10 mol, preferably 0.8 to 1.2 mol, of glycolic acid anilide of formula (III), and 0.5 to 10 mol, preferably 0.5, mol per mol of chlorobenzoxazole
From 3 to 3 mol of base are used. The order in which the reactants are added can be varied as needed, and all components can be metered into the reaction vessel simultaneously. The reaction can be carried out continuously or discontinuously. Purification can be performed by a usual method.

The active compounds according to the invention can be used as defoliants, desiccants, agents for destroying broadleaf plants and in particular as weed killers. Weeds, in a broad sense, refer to all plants that grow in unwanted places. The substances according to the invention act mainly as complete or selective herbicides, depending on the amount used.

The active compounds according to the invention can be used, for example, for the following plants: Dicot weeds of the following genera: Sinapis, Lepidium, Galium,
Genus Stellaria, genus Matricaria,
Anthemis, Galinsaga (Galins)
oga), Chenopodium, Nettle (Urtic)
a), genus Senecio, genus Amaranthus, genus Portulaca, genus Xanthium,
Convolvulus, Sweet Potato (Ipomoe)
a), Polygonum, Polygonum, Sesbani
a), genus Ambrosia, thistle (Cirsium),
Genus (Carduus), genus (Sonchus), genus (Solanum), genus (Rorippa), genus (Rotala), genus (Lindernia), genus (L
amium), stag beetle (Veronica), genus Abu (Abu
tilon), Emex genus, Datura genus (Datura), Violet genus (Viola), Chishima genus (G
aleopsis), Poppy (Papaver) and Centaurea (C
entaurea).

Dicotyledonous plants of the following genera: Cotton (Gossypium), Soybean (Glycine), Chard (Beta), Carrot (Daucus), Bean (Phaseolus), Pea (Pisum), Solanum (Solanum) , Flax (Linum),
Sweet potato (Ipomoea), Vicia faba (Vicia), Tobacco (Nicotiana), Tomato (Lycopersicon), Rattus genus (Arachis), Brassica (Brassica), Akinonogeshi (Lactuca), Cucumber and Cucumber (Cucurbita).

Monocotyledonous plants of the following genus: Echinochloa, Echinochroga (Setaria), Millet (Panicum), Meishishiba (Digitaria), Awagarie (Phleum), Poa (Poa), Festuca (Festuca), Genus Eleusine, genus Brachiaria, genus Lolium, genus Bromus,
Oat (Avena), Cyperus (Cyperus),
Sorghum, Agropyron,
Cynodon and Monochori
a), Genus (Fimbristylis), Genus (Sagit)
taria), Eleocharis, Firefly (Scirp)
us), Paspalum, Platypus (Isch)
aemum), Sphenoclea, Dactyloctenium, Nukabo (Agrosti)
s), genus Alopecurus and Apera.

Monocotyledonous plants of the following genus: Oryza, Maize (Zea), Wheat (Triticum), Barley (H
ordeum), oat (Avena), rye (Secal)
e), sorghum (Sorghum), millet (Panicum), sugar cane (Saccharum), Anas (Ananas), Asparagus and Allium (Alliu)
m).

However, the use of the active compounds according to the invention is not at all limited to these genera, but extends to other plants in the same manner.

Depending on the concentration, the compounds are suitable, for example, for the complete control of weeds on industrial areas and railway tracks, on roads with and without trees and on squares. Similarly, the compounds can be used in perennial plants, such as afforestation, ornamental trees, orchards, vineyards, citrus fields, walnut orchards, banana plantations, coffee plantations, tea plantations, rubber plantations, oil palm plantations. , Planting cocoa, planting small fruit trees and controlling weeds in cultivated hops, and for the selective control of weeds in annually grown plants.

As already mentioned above, because of the very good tolerance of rice in conjunction with the very good action on weeds in rice,
The novel active compounds are preferably used as selective herbicides for rice.

The active compounds are prepared in the customary preparations, for example solutions, emulsions, hydrating solutions, suspensions, dusts, dusting powders, liniments, hydrating powders,
It can be converted into very fine capsules in granules, suspension-emulsion concentrates, natural and synthetic substances impregnated with active compounds, polymer substances for seeds.

These preparations can be prepared in a known manner, for example by adding the active compound to extenders, ie liquid solvents, gaseous and / or solid carriers liquefied under pressure and optionally surfactants, ie emulsifiers and / or dispersants and / or foams. It can be manufactured by mixing with an agent. When water is used as the extender, for example, an organic solvent can be used as an auxiliary solvent. As liquid solvents, mainly aromatic hydrocarbons such as xylene, toluene or alkylnaphthalene, chlorinated aromatic or aliphatic hydrocarbons such as chlorobenzene, chloroethylene or methylene chloride, cyclohexane or paraffin,
Aliphatic hydrocarbons such as mineral oil fractions, alcohols such as butanol or glycol and their ethers and esters, ketones such as acetone, methyl ethyl ketone, methyl isobutyl ketone or cyclohexanone;
Alternatively, strong polar solvents such as dimethylformamide and dimethylsulfoxide and water are suitable.

Solid carriers include ground natural minerals such as, for example, kaolin, clay, talc, chiyoke, quartz, attapulgite, montmorillonite, or diatomaceous earth, and synthetic minerals such as highly dispersed silicic acid, alumina and silicates Are suitable; as solid carriers for granules,
For example, fractions obtained by crushing and fractionating natural rocks such as calcite, marble, pumice, sepiolite and dolomite, as well as inorganic and organic cracked synthetic granules and sawdust, palms, corn cobs and tobacco stems Suitable are granules of organic substances such as nonionic and anionic emulsifiers, such as polyoxyethylene-fatty acid esters, polyoxyethylene fatty alcohol ethers, such as alkylaryl polyglycol ethers, as emulsifiers and / or blowing agents. Alkyl sulphonates, alkyl sulphates, aryl sulphonates and albumin hydrolysis products are suitable; as dispersants, for example, lignin sulfite waste liquors and methylcellulose.

Carboxymethylcellulose and gum arabic, powdered forms such as polyvinyl alcohol and polyvinyl acetate,
Adhesives, such as granular or latex natural and synthetic polymers, and natural and synthetic phospholipids, such as cephalin and lecithin, can be used in the formulation. Other additives can be mineral and vegetable oils.

Colorants such as inorganic pigments such as iron oxide, titanium oxide and Prussian blue, and organic dyes such as alizarin dyes, azo dyes and metal phthalocyanine dyes, and iron, manganese, boron, copper, cobalt, molybdenum and zinc. Minor amounts of nutrients, such as the salt of, can be used.

Preparations are generally from 0.1 to 95% by weight as active compound
And preferably between 0.5 and 90% by weight.

The active compounds according to the invention can be used for weed control as a mixture with known herbicides, as such or in the form of preparations, and are ready-prepare.
d) It is possible to use preparations or tank mixtures.

Also other known active compounds such as fungicides (fu
ngicides), insecticides (insecticides), acaricides (ac
aricides), nematicides, bird repellents,
Mixtures with plant nutrients and soil conditioners are also possible.

The active compound may be used as it is or in the form of a preparation thereof or an application form prepared by further diluting the preparation, for example, in the form of a liquid preparation, suspension, emulsion, powder, coating agent and granule. it can. This form is used in the customary manner, for example by watering, spraying, atomizing, dusting and dusting.

The active compounds according to the invention can be applied before or after germination of the plant. The compound can be mixed into the soil before sowing.

The amounts used of the active compounds can be varied within a considerable range. This amount depends in effect on the nature of the desired effect.
In general, the application rate is the active compound per hectare of soil surface
Between 0.01 and 10 kg, preferably 0.
It is between 05 and 5 kg.

The following examples serve to further illustrate the invention.

Example 1 10.1 g (0.05 mol) dissolved in 20 ml of acetonitrile
Of 2,6-dichlorobenzoxazole in 9.6 g (0.05 mol) of N-methyl glycolate (2,3-dimethylanilide) and 3.1 g (0.0
5 mol) at −20 ° C. in a mixture of powdered potassium hydroxide. The reaction mixture is then subsequently cooled to -20 ° C for 12 hours.
Stir for hours. The reaction mixture is poured onto water for purification, the precipitated solid is filtered off, rinsed with water and dried.

2- (6-chlorobenzoxazol-2 having a melting point of 138 ° C.
11 g (65% of theory) of -yl) -N-methyl-oxyaceto- (2,3-dimethylanilide) are obtained.

The following compounds of the general formula (I) can also be prepared in a corresponding manner and according to the general preparation methods: Example 2 Example 3 Example 4 Example 5 Example 6 Example 7 Example A Pre-germination test Solvent: acetone 5 parts by weight Emulsifier: alkylaryl polyglycol ether 1 part by weight In order to produce a suitable preparation of the active compound, 1 part by weight of the active compound is mixed with the above amount of solvent and An amount of emulsifier is added and the concentrate is diluted with water to the desired concentration.

The test plants are sown in normal soil and after 24 hours the active compound preparation is sprayed on. At that time, it is convenient to maintain a constant amount of the solution per unit area. The concentration of the active compound in the preparation is not particularly important, only the amount of active compound applied per unit area being decisive. Three weeks later,
The degree of damage to the plants is assessed as% damage compared to the development of untreated control plants. The numbers represent the following meanings: 0% = no effect (similar to untreated control plants) 100% = all eradication In this test, the active compounds of the formula (I) according to the invention exhibit very good effects.

Example B Test on Transplanted Rice Pad Solvent: acetone 5 parts by weight Emulsifier: benzyloxy polyglycol ether 1 part by weight To prepare a suitable preparation of the active compound, 1 part by weight of the active compound is mixed with the above amount of solvent, The above amount of emulsifier was added and the concentrate was diluted with water to the desired concentration.

A plant container (surface 1/5000 are [Ar]) is filled with soil from a paddy field. Two types of rice seedlings (kind: Kinmaze) at a 2-3 leaf stage (about 10 cm in height) were transplanted into a container. Echinochloa crus
galli) and / or Mono Korea Vaginalis (Monoc)
horia vaginalis) and / or small rhizome fragments of Eleocharis acicularis L. are sown in soil that retains moisture. Two days after transplanting, the rice was covered with water to a depth of 3 cm. The preparation of active compound is applied to the surface of the water. The concentration of the active compound in the preparation is not critical, only the amount of active compound applied per unit area is decisive.

After using the active compound, the water flow is adjusted for 2 days so as to descend vertically through the plant container at a rate of 2-3 cm per day. The test batch is then kept under overflow conditions and the water depth is 3 cm.

After 4 weeks, the degree of damage to the plants is assessed as% damage compared to the development of untreated control plants. The numbers represent the following meanings: 0% = no effect (similar to untreated control plants) 100% = all eradication In this test the compounds according to the invention, in particular compound (I), show a remarkable tolerance to rice. At the same time, very similar other herbicides which exhibited very good herbicidal action, but also had good herbicidal action, caused severe damage to the rice as indicated below.

The main features and aspects of the present invention are as follows.

1. The following formula (I) Wherein R represents straight-chain or branched alkyl having 1 to 6 carbon atoms, and n represents the number of 0, 1 or 2, but the compound 2- (6-chlorobenzoxazol-2
-Yl) -N-methyl-oxyacetanilide and 2-
Excluding (6-chlorobenzoxazol-2-yl) -N-methyl-oxyaceto- (2-methylanilide), 6-chlorobenzoxazolyl-oxyacetanilide.

2.The following formula 2- (6-chlorobenzoxazol-2-yl) -N
-Methyl-oxyaceto- (2,3-dimethylanilide).

3. Equation (II) Wherein X represents an electron-withdrawing leaving group, 6-chlorobenzoxazole of the formula (III) Wherein R and n have the above-mentioned meanings, and are reacted with glycolic anilide of the formula (1) in the presence of an optional diluent, optionally in the presence of an acid binder, and optionally in the presence of a catalyst. A method for producing (I) 6-chlorobenzoxazolyl-oxyacetanilide.

4. A herbicide comprising at least one 6-chlorobenzoxazolyl-oxyacetamide of formula (I) according to 1 above.

5. Use of 6-chlorobenzoxazolyl-oxyacetamide of general formula (I) as described in 1 above for controlling undesirable weeds.

6. A method for producing a herbicide, comprising mixing 6-chlorobenzoxazolyl-oxyacetamide of the general formula (I) described in 1 above with a bulking agent and / or a surfactant.

 ────────────────────────────────────────────────── ─── Continued on the front page (72) Inventor Robert R. Schmidt Germany-5060 Belgian Federal Republic Jugrat Batzha 2 Imbartovinkel 110 (72) Inventor Harry Strang-Germany Day-4000 Jützsel Dorf 31 Unterdorfsch TRACE 6A (56) Reference JP-A-61-17575 (JP, A) JP-A-54-154762 (JP, A)

Claims (4)

(57) [Claims] (1) The following formula (I) Wherein R represents straight-chain or branched alkyl having 1 to 6 carbon atoms, and n represents the number of 0, 1 or 2, but the compound 2- (6-chlorobenzoxazol-2
-Yl) -N-methyl-oxyacetanilide and 2-
Excluding (6-chlorobenzoxazol-2-yl) -N-methyl-oxyaceto- (2-methylanilide), 6-chlorobenzoxazolyl-oxyacetanilide. 2. Formula (II) Wherein X represents an electron-withdrawing leaving group, 6-chlorobenzoxazole of the formula (III) Wherein R and n have the above-mentioned meanings, and are reacted with glycolic anilide of the above in the presence of an optional diluent, optionally in the presence of an acid binder, and optionally in the presence of a catalyst. The method for producing 6-chlorobenzoxazolyl-oxyacetanilide of the formula (I) according to claim 1. 3. A herbicide comprising at least one 6-chlorobenzoxazolyl-oxyacetanilide of the formula (I) according to claim 1. 4. A method for controlling undesired weeds, which comprises applying 6-chlorobenzoxazolyl-oxyacetanilide of the formula (I) to undesired weeds.