DE3035021A1 - 3-Di:methylamino-4-methyl-6-substd. phenyl-1,2,4-triazinone derivs. - with plant growth regulant, herbicidal and fungicidal activity - Google Patents

Abstract

3-Dimethylamino -4-methyl-6-(substd. phenyl)- 1,2,4-triazin-5- one derivs. (I) are new (where R is substd. phenyl, pref. phenyl substd. by 1-4C alkyl, 1-4C alkoxy, 1-2C haloalkyl with 1-5 identical or different halogen atoms, halogen or phenoxy). The new cpds. are herbicides, esp. selective herbicides, with better herbicidal activity and better selectivity in important crop plants than the known cpd. 3-amino-4-methyl-6-phenyl -1,2,4- triazin-5-one. They can be used against mono- and dicotyledonous weeds in mono- and dicotyledonous crop plants. Rates of application are generally 0.1-10 (pref. 0.1-5) kg/ha. The new cpds. also have plant growth regulant activity and can be used as defoliants, desiccants, haulm-killing agents and germination inhibitors. In addn., they have fungitoxic activity, e.g. against fungal diseases of cereals, esp. rust species.

Description

3-dimethylamino-4-methyl-6-phenyl-1t2,4-triazin-5-ones,

Process for their production and their use as herbicides The present invention relates to new 3-dimethylamino-4-methyl-6-phenyl-1,2,4-triazin-5-ones substituted in the phenyl nucleus, a process for their production and their use as herbicides, in particular as selective herbicides.

It has already become known that 1,2,4-triazin-5-one derivatives, such as 3-amino-4-methyl-6-phenyl-1,2,4-triazin-5-one, as a weed control agent can be used (cf. DE-OS 1 670 912 (Le A lo 914)).

The effect of this compound is, however, especially at low levels Application rates, not always sufficient.

There were new 3-dimethylamino-4-methyl-6-phenyl-1,2,4-triazin-5-ones of the general formula I. in which R stands for substituted phenyl, found.

It has also been found that the 3-dimethylamino-4-methyl-6-phenyl-1,2,4-triazin-5-ones of the formula (I) are consumed when 3-methylmercapto-4-methyl-6-phenyl -l, 2,4-triazin-5-ones of the formula II in which R has the meaning given above, reacts with dimethylamine in the presence of a diluent.

It was also found that the 3-dimethylamino-4-methyl-6-phenyl-l, 2,4-triazin-5-ones of the formula (I) are good herbicidal, in particular also selective herbicidal Have properties.

Surprisingly, the compounds according to the invention are the previously known 3-Amino-4-methyl-6-phenyl-l 2,4-triazin-5-one, which is a chemically and effectively obvious substance is superior in the herbicidal effect and also show better selectivity in important crops. The invention Active ingredients thus represent a significant enrichment of herbicidal agents, in particular selective chemical weed control.

The 3-dimethylamino-4-methyl-6-phenyl-1,2,4-triazin-5-ones according to the invention are generally defined by the formula (I). In this formula, R stands for phenyl, which is preferably substituted by one of the following radicals: straight-chain or branched alkyl or alkoxy each having 1 to 4 carbon atoms, haloalkyl or haloalkoxy each having 1 to 2 carbon and 1 to 5 identical or different Halogen atoms (such as, in particular, fluorine and chlorine atoms), halogen or phenoxy.

Particularly preferred are those compounds of the formula (I) in where R stands for fluorine, chlorine, methyl, isopropyl, tert-butyl, methoxy, isopropoxy, Trifluoromethyl, trifluoromethoxy or phenoxy substituted phenyl.

If, for example, 3-methylmercapto-4-methyl-6- (3-methylphenyl) -l, 2,4-triazin-5-one and dimethylamine are used as starting materials, the course of the reaction can be represented by the following equation: The 3-methylmercapto-4-methyl-6-phenyl-1,2,4-triazin-5-ones to be used as starting materials for the process according to the invention are generally defined by the formula (II). In this formula, R preferably represents those radicals which have already been mentioned in the description of the substances of the formula (I) according to the invention as being preferred for these substituents.

The 3-methylmercapto-4-methyl-6-phenyl-1,2,4-triazin-5-ones of the formula (II) are known (cf. DE-OS 1 670 912), or they can be used in a generally known manner and way can be obtained by phenylglyoxylic acids of the formula R-CO-CO-OH (111) in which R has the meaning given above, with 4-methyl-thiosemicarbazide of the formula CH3-NH-CS-NH-NH2 (Iv) in The presence of water and an organic solvent, such as dimethylformamide, reacts at temperatures between 60 and 1200C, and the resulting 5-mercapto-4-methyl-6-phenyl-1,2,4-triazin-5-ones of the formula in which R has the meaning given above, with an alkylating agent, such as methyl iodide, in the presence of alkali metal alcoholates, such as sodium methylate, with excess alcohol being used as solvent, at temperatures between 20 and 100 oC.

The phenylglyoxylic acids of the formula (In) are known and are used in generally known manner obtained by adding appropriate benzoyl cyanides hvdrolyzed with concentrated mineral acids, such as in particular concentrated hydrochloric acid .

Preferred diluents for the reaction according to the invention are preferred Organic solvents such as isopropanol / glacial acetic acid in particular.

The reaction temperatures can be used in the reaction according to the invention can be varied in a larger area. Generally one works between 40 and 1800C, preferably between 60 and 1500C.

When carrying out the reaction according to the invention, preference is given to using to 1 mole of the compound of the formula (II) 1 to 2 moles of dimethylamine. The isolation of the compounds of the formula (I) is carried out in a generally customary manner.

The active compounds according to the invention influence plant growth and can therefore be used as defoliants, desiccants, haulm killers, sprout inhibitors and especially as a herbicide be turned. Weeds in the broadest sense are all plants that grow in places where they are undesirable. Whether the substances according to the invention as total or selective The effect of herbicides depends essentially on the amount used.

The active compounds according to the invention can be used, for example, in the following plants are used: Dicot weeds of the genera: Sinapis, Lepidium, Galium, Stellaria, Matricaria, Anthemis, Galinsoga Chenopodium, Urtica, Senecio, Amaranthus, Portulaca, Xanthium, Convolvulus, Ipomoea, Polygonum, Sesbania, Ambrosia, Cirsium, Carduus, Sonchus, Solanum, Rorippa, Rotala, Lindernia, Lamium, Veronica, Abutilon, Emex, Datura, Viola, Galeopsis, Papaver, Centaurea.

Dicot cultures of the genera: Gossypium, Glycine, Beta, Daucus, Phaseolus, Pisum, Solanum, Linum, lpomoea, Vicia, Nicotiana, Lycopersicon, Arachis, Brassica, Lactuca, Cucumis, Cuburbita.

Monocot weeds of the genera: Echinochloa, Setaria, Panicum, Digitaria, Phleum, Poa, Festuca, Eleusine, Brachiaria, Lolium, Bromus, Avena, Cyperus, Sorghum, Agropyron, Gynodon, Monochoria, Fimbristylis, Sagittaria, Eleocharis, Scirpus, Paspalum, Ischaemum, Sphenoclea, DaSyloctenium, Agrostis, Alopecurus, Apera.

Monocot cultures of the genera: Oryza, Zea, Triticum, hordeum, Avena, Secale, Sorghum, Panicum, Saccharum, Ananas, Asparagus, Allium.

However, the use of the active ingredients according to the invention is by no means limited to these genera, but extends in the same way to other plants.

-The compounds are suitable depending on the concentration for total weed control z. B. on industrial and track systems and on paths and Places with and without trees. Likewise, the compounds can be used for weed control in permanent crops, e.g.

Forest, ornamental trees, fruit, wine, citrus, nut, banana, coffee, Tea, rubber, oil palm, cocoa, berry fruit and hops plants and for selective Weed control can be used in annual crops.

The active ingredients according to the invention show in addition to a very good general herbicidal effect good tolerance to useful plants. So it is e.g.

also possible, important grass weeds, such as Echinochloa, selectively in important crops such as

in corn, to combat.

The active ingredients can be converted into the usual formulations, such as solutions, emulsions, wettable powders, suspensions, powders, dusts, pastes, soluble powders, granulates, suspension emulsion concentrates, active ingredient-impregnated Natural and synthetic materials, finest encapsulation in polymer materials.

These formulations are prepared in a known manner, for example by Mixing the active ingredients with extenders, i.e. liquid solvents and / or solid carriers, optionally with the use of surface-active agents, that is, emulsifiers and / or dispersants and / or foam-generating agents. If water is used as an extender, organic solvents, for example, can also be used can be used as co-solvents. The liquid solvents used are essentially in question: aromatics such as xylene, toluene, or alkylnaphthalenes, chlorinated aromatics or chlorinated aliphatic hydrocarbons such as chlorobenzenes, chloroethylenes or methylene chloride, aliphatic hydrocarbons such as cyclohexane or paraffins, e.g. petroleum fractions, alcohols such as butanol or glycol as well as their ethers and esters, Ketones, such as acetone, methyl ethyl ketone, methyl isobutyl ketone or cyclohex = Za, are strong polar solvents such as dimethylformamide and dimethyl sulfoxide, and water.

The following can be used as solid carriers: e.g. natural rock flour, such as kaolins, clays, talc, chalk, quartz, attapulgite, montmorillonite or diatomaceous earth and synthetic minerals such as fumed silica, alumina and Silicates; as solid carrier materials for granulates are possible: e.g.

broken and fractionated natural rocks such as Calcite, Marble, pumice, sepiolite, dolomite and synthetic granules made from inorganic and organic flours as well as granules made of organic material such as sawdust, coconut shells, Corn on the cob and tobacco stalks; come as emulsifying and / or foam-producing agents in question: e.g. non-ionic and anionic emulsifiers, such as polyoxyethylene fatty acid esters, Polyoxyethylene fatty alcohol ethers, e.g. alkylaryl polyglycol ethers, alkyl sulfonates, Alkyl sulfates, aryl sulfonates and protein hydrolysates; come as a dispersant in. Question: e.g. lignin sulphite liquor and methyl cellulose.

Adhesives such as carboxymethyl cellulose, natural and synthetic powdery, granular or latex-like polymers are used such as gum arabic, polyvinyl alcohol, polyvinyl acetate.

Dyes such as inorganic pigments, e.g.

Iron oxide, titanium oxide, ferrocyan blue and organic dyes such as Alizarin, azo-metal phthalocyanine dyes and trace nutrients such as salts of Iron, manganese, boron, copper, cobalt, molybdenum and zinc can be used.

The formulations generally contain between 0.1 and 95% by weight Active ingredient, preferably between 0.5 and 90% by weight.

The active compounds according to the invention can be used as such or in their formulations can also be used in a mixture with known herbicides for weed control, being ready-made formulation or tank mix is possible. Also one Mixture with other known active ingredients, such as fungicides, insecticides, acaricides, Nematicides, bird repellants, growth substances, plant nutrients and Soil structure improvers is possible.

The active ingredients can be in the form of their formulations or as such the use forms prepared therefrom by further dilution, such as ready-to-use Solutions, suspensions, emulsions, powders, pastes and granulates can be used. It is used in the usual way, e.g. by watering, squirting, atomizing, Dusting or scattering.

The active ingredients according to the invention can be used both before and after Emergence of the plants are applied.

The application is preferably after the emergence of the plants, ie in the post-emergence procedure.

They can also be incorporated into the soil before sowing.

The active compounds according to the invention can also be used as a mixture with oils or surface-active substances are applied.

The amount of active ingredient used can fluctuate over a wide range. It essentially depends on the type of effect you want. In general the application rates are between 0.1 and 10 kg of active ingredient per hectare, preferably between 0.1 and 5 kg / ha.

Some of the active compounds according to the invention are also fungitoxic Effectiveness, e.g. against fungal diseases of the grain, especially against types of rust.

Preparation examples Example 1 68 g (1.5 mol) of dimethylamine are passed into a mixture of 3 l of isopropanol and 80 g of glacial acetic acid while cooling with ice. This reaction solution is then mixed with 247 g (1 mol) of 3-methylmercapto-4-methyl-6- (3-methylphenyl) -1,2,4-triazln-5-one. The mixture is allowed to warm to room temperature and then refluxed for 30 hours. It is then cooled to 10 ° C., seeded and the solid which crystallizes out is filtered off with suction. Recrystallization from ligroin / isopropanol (5: .1) gives 160 g of 3-dimethylamino-4-methyl-6- (3-methylphenyl) -1,2,4-triazin-5-one with a melting point of 94 -960C.

The mother liquor is concentrated and the residue is triturated with water. The oil is taken up in ethyl acetate, washed with sodium hydrogen carbonate, over Dried sodium sulfate and concentrated. The residue crystallizes on trituration with ligroin. After recrystallization from ligroin / isopropanol (5: 1) one obtains 49 g of 3-dimethylamino-4-methyl-6- (3-methylphenyl) -1, 2i 4-triazin-5-one, melting point 93-95 ° CI. The total yield is thus -209 g (86% of theory).

Production of the starting product a) Production of the 3-methyl mercapto compound 233 g of 3-mercapto-4-methyl-6- (3-methylphenyl) -1,2,4-triazin-5-one are added to 54 g of sodium methylate in 1400 ml of methanol. After complete dissolution, 70 ml of methyl iodide in 100 ml of methanol are added dropwise. The mixture is stirred overnight at room temperature, the crystalline precipitate is filtered off with suction, washed with a little methanol and dried. 177 g of 3-methylmercapto-4-methyl-6- (3-methylphenyl) -l, 2 '4-triazin-5-one with a melting point of 93-95 ° C. are obtained.

The mother liquor is concentrated, the residue is triturated with water, vacuumed and dried. 42 g of 3-methylmercapto-4-methyl-6- (3-methylphenyl) -1,2J4-triazin-5-one are obtained of melting point 92-940C.

The total yield is therefore 219 g (88.5% of theory).

b) Preparation of the 3-mercapto compound 164 g (1 mol) of 3-methylphenylglyoxylic acid in 300 ml of dimethylformamide are added dropwise to 105 g of 4-methylthiosemicarbazide in 2 l of water at a bath temperature of 100 ° C. The mixture is stirred for 20 hours at this temperature, cooled, the precipitate formed is filtered off with suction, washed with water and with alcohol and dried. 191 g (82% of theory) of 3-mercapto-4-methyl-6- (3-methylphenyl) -1,2,4-triazin-5-one with a melting point of 193-195 ° C. are obtained.

c) Production of 3-methylphenyl-glyoxylic acid 145 g (1 mol) of 3-methylbenzoyl cyanide are stirred in 1 l of hydrochloric acid at 50 ° C. for 16 hours. It is allowed to cool and stirred into 5 l of water. This reaction mixture is extracted five times with 500 ml of methylene chloride each time, dried and concentrated. 145 g (88% of theory) of 3-methylphenylglyoxylic acid are obtained as an oil.

d) Preparation of 3-methylbenzoyl cyanide 154.5 g (1 mol) of 3-methylbenzoyl chloride and 180 g of copper (I) cyanide in 100 ml of acetonitrile are stirred for 1 hour at room temperature and heated under reflux for 2 hours.

The reaction solution is then allowed to cool, filtered off with suction and concentrated Filtrate. The residue is triturated in toluene, filtered off with suction and the filtrate again constricted.

The residue is distilled. You'll get 9 g ('82% of theory) 3-methylbenzoyl cyanide with a boiling point of 118-1220C / 26.6 mbar.

The compounds of the general formula (1) listed in the table below are analogous. obtain: The new compounds of the formula (I) can also be referred to more precisely as 3-dimethylamino-4-methyl-6-phenyl-1,2 2 4-triazin-5 (4H) -ones.

Tabel At- game R (OC) oc No. R melting point 2 O -O 103 3 F3C b 90-92 4 cl b 123-124 5 H CO lol 6 C1- O- 161-163 6th 7y- 119-121 8 F3C- 133-135 9 F3CO-- 120-122 lo F3CO Le b 20 554 80-82 Ts: 20,554 Examples of use: Example A Post-emergence test Solvent: 5 parts by weight of acetone Emulsifier: 1 part by weight of alkylaryl polyglycol ether To prepare an appropriate addition of active ingredient, 1 part by weight of active ingredient is mixed with the specified amount of solvent, the specified amount of emulsifier is added and the concentrate is diluted with water to the desired level Concentration.

Test plants which have a Height ton 5 - 15 cm have such that the amounts of active ingredient given in the table applied per unit area. The concentration of the spray liquor will be like this chosen that the amounts of active ingredient given in the table in 2000 1 water / ha be applied.

After three weeks, the degree of damage to the plants is rated in % Damage compared to the development of the untreated control. It means: O O / o = no effect (like untreated control) 100 O / o = total destruction In this test, for example, the compound according to Preparation Example 1 shows a better one general herbicidal effectiveness and better selectivity in corn than that from Compound (A) known in the art, i.e.

3-Amino-4-methyl-6-phenyl-1,2,4-triazin-5-one of the formula

Claims (9)

Claims 1) 3-Dimethylamino-4-methyl-6-phenyl-1,2,4-triazin-5-ones of the general formula (I) in which R stands for substituted phenyl. 2) 3-Dimethylamino-4-methyl-6-phenyl-1,2,4-triazin-S-ones of the general Formula (1) according to claim 1, characterized in that R represents by alkyl or Alkoxy each with 1 - 4 carbon atoms, haloalkyl or haloalkoxy each with 1 - 2 carbon atoms and 1 - 5 identical or different halogen atoms, halogen or phenoxy substituted phenyl. 3) 3-Dìmethylamino-4-methyl-6-phenyl-1,2,4-triazin-5-ones of the general Formula (I) according to claim 1, characterized in that R represents fluorine, chlorine, Methyl, isopropyl, tert-butyl, methoxy, isopropoxy, trifluoromethyl, trifluoromethoxy. or phenoxy substituted phenyl. 4) 3-Dimethylamino-4-methyl-6- (3-methylphenyl) -1,2,4-triazin-5-one of the formula according to claim 1. 5) Process for the preparation of 3-dimethylamino-4-methyl-6-phenyl-1,2,4-triazin-5-ones of the general formula in which R stands for substituted phenyl, characterized in that 3-methylmercapto-4-methyl-6-phenyl-1,2,4-triazin-5-ones of the general formula in which R has the meaning given above, reacts with dimethylamine in the presence of a diluent. 6) Herbicidal agents, characterized by a content of 3-dimethylamino-4-methyl-6-phenyl-1,2,4-triazin-5-ones of the general formula in which R stands for substituted phenyl. 7) method of controlling unwanted plant growth, thereby characterized in that 3-dimethylamino-4-methyl-6-phenyl-1 t 2,4-triazin-5-ones act according to claim 6 on the unwanted plants or their habitat leaves. 8) Use of 3-dimethylamino-4-methyl-6-phenyl-1,2,4-triazin-5-ones according to claim 6 for controlling plant growth. 9) Process for the preparation of herbicidal agents, characterized in that that 3-dimethylamino-4-methyl-6-phenyl-1,2,4-triazin-5-ones according to claim 6 with Diluents and / or surfactants mixed together.