DE2908963A1 - 6-Tert. butyl-3-di:methylamino-4-methyl-1,2,4-triazin-5-one - useful as herbicide and plant growth regulator (PT 8.8.80) - Google Patents

Abstract

The triazine deriv. of formula (I) is new: (I) is prepd. e.g. by reacting the 3-alkylthio analogue with (CH3)2NH. (I) is a herbicide (total or selective depending on application rate and also has plant-growth regulating effects e.g. defoliation, desiccation and germination inhibition. It is more active than known 3-substd.-4-alkyltriazines and has good activity against weed grasses and broad-leaved plants, particularly Galium species. (I) may be used in crops of maize, groundnuts, soya, cotton, rice and other cereals, with application rate 0.01-10 pref. (0.01-5) kg/ha, esp. pre-emergence.

Description

6.-tert-Butyl-3-dimethylamino-4-methyl-1,2,4-triazine-5-

(4H) -one, process for its preparation and its use as herbicidal The present invention relates to a new triazinone derivative, method for its manufacture and its use as a herbicide.

It has already become known that 1,2,4-triazin-5 (4H) -ones are used as weed control agents can be used.

For example, it is known that certain 3-substituted 4-AZk-1-2,2,4-triazin-5 (4H) -ones as herbicides are cf. DE-OS 16 70 912). The effect of these preparations however, it is not always sufficient in low doses.

The new 6-tert-butyl-3-dimethylamino--4-methyl-1,2,4-triazin-5 (4H) -one of the formula was used found.

The triazinone of the formula (I) is obtained if (a) a 6-tert-butyl-4-methyl-3-alkylthio- (or 3-aralkylthio) -triazin-5 (4H) -one of the general formula in which R stands for alkyl or aralkyl, optionally in the presence of a diluent and optionally in the presence of a lower aliphatic carboxylic acid with dimethylamine, or if (b) 3,3-dimethyl-2-oxo-butyric acid of the formula (CH3) 3C- CO-COOH (III) in aqueous solution with a 3-amino-1,1,2-triethylguanidinium salt of the formula in further X is Cl, Br or I, is implemented.

The @ns triazinon of the formula (I) has strong herbicidal properties on.

Or the novel drying derivative according to the invention shows in drops a considerably higher herbicidal effect than those previously known from the prior art 6-su @@@@@ erten 4-alkyl-1,2,4-triazin-5 (4H) -ones.

If, for example, 6-tert-butyl-4-methyl-3-tin @@ - 1,2,4-triazin-5 (4) -one and dimethylamine as an ante, the reaction can proceed according to process @e aich the following equation is given.

If 3,3-dimethyl-2-oxo-butyric acid and, for example, 3-amino-1,1,2-trimethyl-guanidinium hydroiodide are used as starting materials, the course of the reaction according to process (b) can be represented by the following equation: Most of the starting materials which can be used according to the invention are known. For example, the 6-tert-butyl-4-methyl-3-methylthio-1,2,4-triazin-5 (4H) -one (IIa) which can be used for process (a) was obtained in 11% yield by N- Methylation of 6-tert-butyl-3-methylthio-1,2,4-triazin-5 (4H) -one prepared (cf. Z. Naturf. 31 B, 1122-1126 (1976)). However, it is more favorable to prepare this compound by S-methylation of 6-tert-butyl-4-methyl-5-oxo-3-thioxo-tetrahydro-1,2,4 (2H, 4H) -triazine (V) (see Sect . Production examples). In a similar way, other 3-alkylthio- or 3-aralkylthiotriazinones, for example 3-ethylthio-, 3-propylthio, 3-benzylthio- or 3- (4-chlorobenzylthio) -triazinones can be synthesized, which in the same way as starting materials for processes (a) are suitable.

3,3-Dimethyl-2-oxo-butyric acid (III) is known. The technical production this connection can, for example, according to the method specified in DE-OS 26 48 300 take place.

3-Amino-1,1,2-trimethyl-guanidinium-hydroiodide (IV, X = I) can also be prepared by a method known from the literature (cf. J. Org. Chem. 19, 1807-1817 (1954)). The corresponding hydrochloride (IV, X = Cl) and hydrobromide (1V, X = Br) can be prepared in an analogous manner.

In process (a), all inert organic diluents can be used Solvent in question. These include hydrocarbons such as toluene and xylene; chlorinated aromatic hydrocarbons such as chlorobenzene, 1,2-dichlorobenzene, 1,2,4-trichlorobenzene; Ethers such as tetrahydrofuran, dioxane; Alcohols such as methanol, ethanol, propanol, isopropanol; Amides such as N, N-dimethylformamide, tetramethylurea or sulfoxides such as dimethyl sulfoxide.

Isopropanol is preferably used for the reaction.

The reaction temperatures can in process (a) in a larger Range can be varied. In general, one works at temperatures between about 20 and about 1700C, preferably between 60 and 900C.

The reaction can be pressureless as well as at elevated pressures executed will.

There is a particularly advantageous embodiment of process (a) in that in the presence of at least the equimolar amount of a lower aliphatic Carboxylic acid works. Acetic acid is preferably used for this. This method makes it possible to manage with a relatively small excess of dimethylamine. At this Embodiment can increase the reaction rate by adding a catalytic Amount of an organic sulfonic acid can be increased. Preferably used for this p-toluenesulfonic acid.

When carrying out process (a) according to the invention according to this preferred process variant is set to 1 mol of the 3-alkylthio- or 3-aralkylthio-triazinone of the formula (II) expediently 1 to 2 mol of a lower aliphatic carboxylic acid, 0.01 to 0.05 mol of an organic sulfonic acid and 1 to 2 mol of dimethylamine, heated until the mercaptan has been split off and then works up. this can e.g.

done in such a way that you evaporate the residue with excess stirred aqueous mineral acid and separated off undissolved impurities. By addition an excessive amount of a base such as ammonia becomes the reaction product precipitated in high purity.

Process (b) is carried out in aqueous solution.

The sodium salt of 3,3-dimethyl-2-oxo-butyric acid is expedient (III) presented in aqueous solution, and near addition of the 3-amino-1,2,4-trimethylguanidinium salts (I7) is the acid (III) by adding mineral acid, for example hydrochloric acid, released.

The reaction temperatures can also be used in process (b) in can be varied over a larger area.

In general, one works at temperatures between about 50 and about 100 ° C, preferably between 65 and 90 ° C.

ta Process (b) is in general carried out at normal pressure.

When carrying out process (b), 1 mole of one is used aqueous solution of the Na salt of 3,3-dimethyl-2-oxo-butyric acid 1 to 1.1 mol of a 3-Amino-1,1,2-trimethyl-guanidinium salt (IV) and after adding mineral acid, for example hydrochloric acid, until the reaction has ended. Then the work-up in the same way as for procedures.

The active ingredient according to the invention influences plant life and can therefore as a defoliant, desiccant, killing agent, sprout inhibitor and insbere used as a weed killer who-are weeds in the broadest sense to understand all plants that grow in places where they are unsuitable for The substance according to the invention acts as a total elective herbicide depends essentially on it r applied amount.

The active ingredient 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, Ipomoea, 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, Cynodon, Monocharia, Fimbristylis, Sagittaria, Eleocharis, Scirpus, Paspalum, Ischaemum, Sphenoclea, Dac-blloctenium, 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 ingredient according to the invention is by no means limited to these genera, but extends in the same way to other plants.

Depending on the concentration, the compound is suitable for Total weed control e.g. on industrial and rail systems and on paths and squares with and without tree growth. Likewise, the connection to weed control in permanent crops e.g. forest, ornamental wood, fruit, wine, citrus, nut, banana, Coffee, tea, rubber, b.lpalm, cocoa, berry fruit and hops plants and for selective weed control can be used in annual crops.

The active ingredient according to the invention shows in particular in addition to a very good effect against grass-like weeds also a herbicidal effect against broad-leaved ones Weeds, especially against Galium species. A selective use of the invention Active ingredient is possible, preferably in corn, peanuts, soybeans, cotton, Rice and other grains.

The active ingredient 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 made in a known manner, e.g. Mixing the active ingredient 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 main liquid solvents are in question: Aromatics such as xylene, toluene, or alkylnaphthalenes, chlorinated Aromatics or chlorinated aliphatic hydrocarbons such as chlorobenzenes and 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 cyclohexanone, 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 and granules made from organic material such as sawdust, coconut shells, corn on the cob and tobacco stalks; as emulsifying and / or foam-producing agents are possible: 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 waste liquors and methyl cellulose.

Adhesives such as carboxymethyl cellulose, natural and synthetic powdery, granular or latex shaped 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, pluckers, 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 ingredient according to the invention can be used as such or in its formulations can also be used in a mixture with known herbicides for weed control, finished formulation or potion mix is possible.

Also a mixture with other known active ingredients, such as fungicides, Insecticides, acaricides, nematicides, bird repellants, growth substances Plant nutrients and soil structure improvers are possible.

The active ingredient can be used as such, in the form of its formulations or 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 pouring, syringe, spraying, Dusting or scattering.

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

The application is preferably before the emergence of the plants, that is in the pre-emergence procedure. It can also be pre-sown in the ground be incorporated.

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 0.01 and 10 kg of active ingredient per ha, preferably between 0.01 and 5 kg / ha. Preparation examples A) 6-tert-butyl-3-dimethylamino-4-methyl-1,2! 4-triazin-5 (4H) -one (I) Example 1 - [according to process (a, 7 1850 g of acetic acid and 125 g of p-toluenesulfonic acid are placed in 15 liters of isopropanol. 1850 g of dimethylamine are passed in with cooling, then 5250 g (24.65 mol) of 6-tert. Butyl-4-methyl-3-methylthio-1,2,4-triazin-54H) -one and heated under reflux until the evolution of methyl mercaptan has ended. The majority of the solvent is then distilled off at an internal temperature of 80 ° -90 ° C. while nitrogen is passed through.

The oily residue is stirred at 0 ° -50 ° C. with 25 liters of a 5 % hydrochloric acid and 2 liters of chloroform. The organic phase is separated and discarded. 3 liters of 25% ammonia solution are added to the aqueous phase with cooling, the reaction product precipitating in crystalline form. You suck off at OOC, wash with little ice water and dries at 500C.

4438 g (86% of theory) of the abovementioned compound (I) are obtained of m.p. 89-91 ° C. The purity determined by gas chromatography is above 99 %. The compound can be distilled: bp 1150Clo, 03 mbar.

Example 2 - / according to the method (bL7 To 2 liters of an aqueous solution of the sodium salt of 3,3-dimethyl-2-oxo-butyric acid, which contains 1 mol, is added 244 g (1 mol) of 3-amino-1,1,2-trimethylguanidinium hydroiodide and 100 ml of 35% hydrochloric acid. The mixture is heated to 80 ° C. for 5 hours, cooled to 20 ° C. and then 50 ml of 25% strength are added dropwise Ammonia solution too. After suctioning off at OOC, washing with a little ice water and drying 196 g (93% of theory) of the abovementioned compound (I) are obtained at 50 ° C. M.p. 89-91 ° C.

B) Starting materials for process (a) a) 6-tert-butyl-4-methyl-5-oxo-3-thioxo-tetrahydro-1,2,4- (2H, 4H) -triazine (V) 4725 g (45 mol) of 4-methyl-thiosemicarbazide are dissolved in 25 liters of water and 6 liters of 35% strength hydrochloric acid, and 92 liters of an aqueous solution of the Na salt of 3,3-dimethyl-2-oxo-butyric acid are added with stirring which contains 46 moles and refluxes for 10 hours. It is suctioned off at 50 ° C., washed with water and dried at 80 ° C. 7340 g (82% of theory) of compound (V) with a melting point of 2140C are obtained.

b) 6-tert-butyl-4-methyl-3-methylthio-1,2,4-triazin-5- (4H) -one (IIa) a solution of 1145 g of NaOH in 57 liters of water, 30 ml of 3-benzyl-4-hydroxy-biphenyl polyglycol ether as an emulsifier and 5690 g (28.6 mol) of 6-tert-4-methyl-5-oxo-3 thioxo-tetrahydro-1,2,4 (2H, 4H) -triazine 4302 g (30.3 mol) of methyl iodide are added dropwise (or 2900 g of methyl bromide are introduced) and the mixture is stirred until the slightly exothermic reaction ends and a 7 - 8 is reached. After filtering off with suction, washing with water and drying at 50 ° C., 5810 g of 95% of theory of compound (IIa) with a melting point of 90 ° -100 ° C. are obtained.

The crude product is sufficiently pure for further implementation. One Sample recrystallized from ethanol or petroleum ether melts at 104-105 ° C example A Pre-emergence test Solvent: 5 parts by weight acetone Emulsifier: 1 part by weight Alkylaryl polyglycol ether For the production of an appropriate preparation of active ingredients mixing 1 part by weight of active ingredient with the specified amount of solvent, add the specified amount of emulsifier and dilute the concentrate with water The desired concentration.

Seeds of the test plants are sown in normal soil and after Doused with the active ingredient preparation for 24 hours.

The amount of water per unit area is expediently kept constant. The concentration of the active substance in the preparation does not matter, it is decisive is only the amount of active ingredient applied per unit area. After three weeks it will the degree of damage to the plants is rated in% damage in comparison to development the untreated control. It means: O% = no effect (like untreated Control) 100% = total destruction In this test, the active ingredient (I) shows a excellent effect.

Example B Post-emergence test Solvent: 5 parts by weight acetone Emulsifier; 1 part by weight of alkylaryl polyglycol ether for the preparation of a suitable Active ingredient preparation is mixed 1 part by weight of active ingredient with the specified Amount of solvent, add the specified amount of emulsifier and dilute the concentrate with water to the desired concentration.

Test plants which have a Height of 5 - 15 cm have so that the respectively desired amount of active ingredient per unit area atis brought. The concentration of the spray liquor is chosen so that in 2000 1 water / ha the particular amount of active ingredient desired is applied. After three weeks the degree of damage to the plants is rated in, damage in comparison to Development of the untreated control. It means: O% = no effect (like untreated Control) 100% = total destruction In this test too, the active ingredient (I) shows an excellent effect

Claims (6)

Claims 6-tert-butyl-3-dimethylamino-4-methyl-1,2,4-triazin-5 (4H) -one of the formula 2. Process for the preparation of 6-tert-butyl-3-dimethylamino-4-methyl-1,2,4-triazin-5 (4H) -one (I), characterized in that (a) a 6- tert-Butyl-4-methyl-3-alkylthio- or 3-aralkylthio) -triazin-5 (4H) -one of the general formula Alkyl or aralkyl is preferably in the presence of a diluent and optionally in the presence of a lower aliphatic carboxylic acid with dimethylamine, or 1-trimethyl-2-oxo-butyric acid of the formula (CH3) 3C-CO-COOH (III) in aqueous solution with a 3-amino-1,1,2-trimethylguanidinium salt of the formula in which X is Cl, Br or I, converts. 3) Herbicidal agents, characterized by a content of 6-tert-butyl-3-dimethylamino-4-methyl-1,2,4-triazin-5 (4H) -one according to claim 1. 4) method of controlling unwanted plant growth, thereby characterized in that 6-tert-butyl-3-dimethylamino-4-methyl-1,2,4-triazin-5 (4H) -one act according to claim 1 on the undesired plants or their habitat leaves. 5) Use of 6-tert-butyl-3-dimethylamino-4-methyl-1,2,4-triazin-5 (4H) -one according to claim 1 for controlling plant growth. 6) Process for the preparation of herbicidal agents, characterized in that that 6-tert-butyl-3-dimethylamino-4-methyl-1,2,4-triazin-5 (4H) -one according to -Anspruch 1 mixed with extenders and / or surfactants.