DE2726016A1 - 4-Amino-3-methylthio-1,2,4-triazinone deriv. - useful as selective herbicides, desiccant and defoliant - Google Patents

Abstract

4-Amino-6-(2,2-dichloro-1-methyl-cyclopropyl)-3-methylthio-1,2,4-- triazin-5-one of formula (I) is new. It is prepd. by reacting thiocarbohydrazide with (2,2-dichloro-1-methyl-cyclopropyl)glyoxylic acid (or its reactive deriv.), then methylating. (I) is a herbicide and can also be used as defoliant and dessicant to facilitate harvesting of e.g. cotton and potatoes. It has good activity pre- or post emergence against graminaceous weeds and is selective in crops of e.g. maize, soya, rye, barley and oats. The pref. application is 0.5-2 kg/hectare, applications of 3 kg/hectare provide a total herbicidal effect.

Description

The present invention relates to a new 1.2.4-triazinone

derivative, process for its production, herbicidal compositions which contain this 1,2.4-triazinon-5-one derivative as an effective component, and also the use of this 1,2,4-triazinon-5-derivative or the compositions containing it for combating undesirable Plant growth The new Triazinonderiva1 corresponds to the formula The production can take place according to a method described by Dornow et al (Der. 97, 2173-79, (1964)). According to this process, an alkyl or arylglyoxylic acid is condensed with thiocirbohydrazide to give a 6-aryl- or alkyl-substituted 4-amino-3-thiono-1,2,4-triazinon-5 and then converted to the 3-methylmereaptoderivat by means of a methylating agent. Methyl iodide, methyl bromide or dimethyl sulfate in a basic medium can be used as methylating agents.

Applied to the present invention, the following reaction takes place: + H2N-NH-CS-NH2 Instead of the free acid, esters or amides can also be used for the condensation with the thiocarbon hydrazide.

The reactions are preferably carried out in polar solvents, such as Methanol, ethanol, dimethylformamide, dimethyl sulfoxide, water or mixtures thereof, at temperatures between 0 ° C and the boiling point of the solvent or of the mixtures lie.

The reactions of thiocarbohydrazine with the amides of (2.2-dichloro-1-methylcyclopropyl) -glyoxylic acid, which can also be substituted, result in the equivalent of an acid, preferably Sulfuric acid or hydrochloric acid in an amount at least equal to that of the equivalents Amide amount corresponds.

The methylation is preferably carried out in a manner known per se Methyl iodide or methyl bromide.

The (2.2-dichloro-1-methylcyclopropyl) glyoxylic acid can, for example according to the method of German patent application P 2708 185 by saponifying the corresponding acyl cyanides in the equivalent of an organic solvent or solvent mixture with gaseous hydrogen chloride and then at a temperature of -700C to about + 700C with wet and subsequent acidic or alkaline hydrolysis of the carboxamide obtained can be obtained.

The acyl cyanides in turn are derived from the corresponding acyl halides available. For example, you can use the German patent application procedure P 27 08 183.0 by reaction with CuCN at temperatures between 50 and 1800C in a mixture of about 1 to 10 parts by weight of an inert carboxylic acid nitrile and about 0.5 to 20 parts by weight of an inert organic solvent, for example Dioxane. According to the German patent application P 27 08 182.9, this production can but also done so that a mixture of about 0.1 to 5 parts by weight of a Alkali metal cyanide and about 0.05 to 2 parts by weight of a copper (I) salt are used and also works in the presence of an inert carboxylic acid nitrile.

The 1,2,4-triazin-5-one derivative of the formula I according to the invention influences plant growth and particularly shows excellent herbicidal properties. It is mainly used for weed control, but can also be beneficial because of its benefits drying and defoliant efficacy as harvesting aid in crops such as Cotton or potatoes can be used.

When combating monocotyledon and dicotyledon weeds, the 1st active ingredient shows of the formula I have an outstanding herbicidal action even at low application rates on unwanted vegetation with significant protection of a number of useful plant crops and therein is surprisingly structurally similar known 1,2,4-triazin-5-one derivatives think. It also includes weed species that are difficult to control.

The inventive triazinon has very good properties against Gramineae, such as millet or millet-like plants, black foxtail (Alopecurus sp.).

The general effectiveness of Triazinones is known, for example that of the compound 4-Amio-6-t-butyl-3-methylthio-1.2.4-triazin-one-5. Different from this the new compound was found primarily in the pre-emergence test at medium concentrations because they are found in some crops of useful plants, for example in maize, soy, rye, Gesture and oats, much more selective.

The application of the present compound chimney in the usual Formulations with equally good success both after emergence (post-emergent) and especially before emergence (preemergent) of the plants. the Application rates for the active ingredient according to the invention can depend on the intended use, Place of use, culture, harmful plant species and population, climatic conditions, etc. fluctuate within wide limits and are surprisingly down. Works in light soils the riazinon derivative according to the present invention generally in application rates from 0.1 kg per hectare and is preferably used in amounts of 0.5 to 2.0 kg used per hectare; in heavy humus-rich and adsorptive soils are higher Apply application rates. With application rates of 3. C kg per hectare and more occurs the total herbicidal effect of this compound against the selectivation in the Foreground.

The following examples illustrate the manufacturing processes for the new compound of formula I. The temperatures in it are in degrees Celsius specified.

example 1 a) Preparation of 2.2-dichloro-1-methyl-cyclopropylglyoxylic acid amide: The 2.2-dichloro-1-methyl-cyclopropanecarboxylic acid methyl ester, which can be prepared in high yield from methyl methacrylate and chloroform, is saponified with KOH / CH3OH to form the free acid and this is converted into the acid chloride with thionyl chloride . The corresponding acid cyanide is then produced with CuCN, which is then saponified to form the acid amide.

White crystals, m.p. 92 to 930C.

b) Preparation of 4-amino-6- (2.2-dichloro-1-methyl-cyclopropyl) -3-mercapto-1.2.4-triazin-5-one: 196 g of 2,2-dichloro-1-methyl-cyclopropylglyoxylic acid amide are added to 1,000 ml of 2N-1COH and reflux. Within half an hour the theoretical amount is N113 released. The temperature is now reduced to 60 ° C., then carried with stirring 106 g of thiocarbohydrazide. The mixture is adjusted to pH 4 with acetic acid and then heated to 1000 C. Crystals precipitate after 5 minutes. , Man heats for another 25 minutes, cools, sucks off, washes and dries.

Almost white crystals, m.p. 258 to 2590C.

Quantity: 243.5 g of 4-amino-6- (2.2-dichloro-1-methyl-cyclopropyl) 3-mercapto-1.2.4-triazin-5-one, corresponding to 91.2% of theory

c) Preparation of 4-amino-6- (2.2-dichloro-1-methyl-cyclopropyl) -3-mercapto-1.2.4-triazin-one-5 196 g of 2,2-dichloro-1-methyl-cyclopropylglyoxylic acid amide and 106 g of thiocarbohydrazide are given in 1.5 ltr. Water containing 70 ml of concentrated hydrochloric acid (d: 1.17). The mixture is heated to 100 ° C. (reflux) while stirring. Crystals fall after 10 minutes the end. Cook for another hour, cool down and work up. 238.5 g of (4-amino-6- (2.2-dichloro-1-methylcyclopropyl) -3-mercapto-1.2.4-triazin-one-5, corresponding to 89.3 ffi d.Th., F. 257 to 2580C.

d) Preparation of 4-amino-6- (2.2-dichloro-1-methyl-cyclopropyl) -3-methylthio-1.2.4-triazin-5-one 53.4 g of 4-amino-6- (2.2-dichloro-1-methyl-cyclopropyl) -3-mer capto-1.2.4-triazin-one-5 is dissolved in a mixture of 200 ml of 2N NaOH and 150 ml of C113011, filtered and add 31 g of methyl iodide. l) the mixture is stirred at room temperature for 6 hours, then the precipitate formed is filtered off with suction, washed and dried.

Light yellow crystals, m.p. 133 to 1340C. Quantity: 52.8 g, accordingly 94 d.Th. 4-Amino-5- (2.2-dichloro-1-methylcyclopropyl) -3-methylthio-1.2.4-triazin-5-one.

The herbicidal effect of the 1,2,4-triazin-5-one derivative according to the invention was determined by the following tests: 1. Herbicidal effect on application of the .active substances before the plants emerge (pre-emergent).

In the greenhouse, test plants were sown in boxes, namely crop plants and mono- and dicotyledon weeds.

After sowing, the active ingredient according to formula I and a commercially available Triazinone derivative sprayed on as an aqueous-ethanolic dispersion. The evaluation the effect achieved on the emerged plants took place 28 days after application. The plants were kept evenly moist during the experiment.

The rating was based on the 6 index: 1 plants undamaged 2 Moderate growth 3 Plant takes care of 4 Light damage 5 Heavy damage 6 Total loss 2. Herbicidal effect when the active ingredients are applied after the plants have emerged (post-emergent).

In a greenhouse, crops were sown and shot up in boxes and weeds in the 4- to 6-leaf stage with an aqueous-ethanolic suspension injected. The evaluation was carried out 28 days after the treatment. The Boiiitierung took place as indicated under 1..

Tested compounds: A: 4-Amino-6-t-butyl-3-methylthio-1.2.4-triazin-5-one (previously known) B: II-Amino-6- (2.2-dichloro-1-methyl-cyclopropyl) -3-methylthio-1.2.4-triazin-5-one (according to the present invention) Pre-emergence post-emergence Test plant 250 g / ha 250 g / ha ABAB Stellaria media 6 5 6 1 Sonchus asper 6 6 6 6 Polygonum persicaria 6 6 6 6 Plantago Lanceolata 6 4 6 1 llatricari. indodora 6 2 # 6 1 Galium aparine 2 2 1 1 Galinsago parviflora 6 6 6 6 Echinochloa crus galli 6 5 6 2 Chenopodium album 6 6 6 2 Digitaria sanguinalis # 6 5 # 6 5 Centaurea cyanus 6 4 6 1 Avena fatua 6 5 6 1 Amaranthus retroflexus # 6 5 # 6 6 Agropyron repens 6 5 6 1 Sinapis alba 6 - 6 6 1 Brassica napus 6 5 6 1 Beta vulgaris 6 6 6 1 Phasaeolus vulgaris 6 2 2 1 Zea mais 6 1 6 1 Soy hispida 5 1 6 1 Triticum aestivum 6 2 6 1 Secale cereale 6 1 6 1 Poa annua 6 4 6 1 J, olium perenne 6 2 G 1 ilordeum vulgare 6 1 6 1 Avena native 6 1 6 1 Apera spica venti 6 6 6 6 Aiopecurus myosuroides # 6 5 6 1 Agrostis tenuis # 6 5 # 6 1 Pre-emergence post-emergence Test plant 500 g / ha 500 g / ha ABAB - Stellaria media 6 6 6 3 Sonchus asper 6 6 6 6 Polygonum persicaria 6 6 6 6 Plantago Lanccolata 6 6 6 6 Matricatia indodora 6 6 6 6 Galium aparine 5 5 5 5 Galinsago parviflora 6 6 6 6 Echinochloa crus gaill 6 6 6 6 Chenopodium album 6 6 6 6 Digitaria sanguinalis 6 6 6 6 Centaurea cyanus 6 6 6 3 Avena fatua 6 6 6 4 Mnaranthus retroflexus 6 6 6 6 Agropyron repens 6 5 6 2 Sinapis alba 6 6 6 1 Brassica napus 6 6 6 6 Beta vuigaris 6 6 6 6 Phasaeolus vulgaris # 6 2 # 6 1 Zea mais 5 1 3 1 Soy hispida 6 2 6 2 Triticum aestivum 6 5 6 1 Secale cereale 6 4 G 1 Poa annua 6 6 6 3 Lolium perenne 6 3 6 1 Horde vulgare # 6 4 6 1 Avena sativa 6 6 6 1 Apera spica venti 6 6 6 6 Alopecurus myosuroides 6 6 6 3 Agrostis tenuis 6 6 6 5 Pre-emergence post-emergence 750 g / ha 750 g / ha Test plant ABAB Stellaria media 6 6 6 1 Sonchus asper 6 6 6 6 Polygonum persicarria 6 6 6 6 Plantago Lancoolata 6 6 6 6 Matricaria indodora 6 6 6 6 Ga3 ium aparine 6 6 5 6 Galinsago parviflora 6 6 6 6 Echinochloa crus galli 6 6 6 6 Chenopodium album 6 6 6 6 Digitatia sanguinalis # 6 6 # 6 6 Centaurca cyanus 6 6 6 5 Avena fatum 6 6 6 6 Amäranthus retroflexus 6 6 6 6 Apropyron repens G 6 6 2 Sinapis alba # 6 6 # 6 5 Brassica napus 6 6 6 G Beta vulgaris 6 6 6 5 Phasaeolus vulgaris # 6 6 # 6 1 Zea mais 5 3 4 1 So yes hispida G 5 6 2 Triticum aestivum G 5 6 2 Secale cereale # 6 5 # 6 2 Poa aniiua 6 6 6 3 Lolium peranne 6 6 6 2 Hordeum vulgare 6 5 6 1 Avena sativ 6 6 6 Apera spica venti 6 6 6 6 Alopecurus myosuroides 6 6 6 4 Agrostis tenuis 6 6 6 6 For the preparation of herbicidal agents, the active ingredient is combined with suitable carriers and / or distribution agents. This is done in a manner known per se by intimately mixing and grinding the active ingredient of the general formula I with suitable carriers, optionally with the addition of dispersants or solvents which are inert towards the active ingredients. The active ingredient can be used as a dusting agent, scattering agent, granules, coated granules, impregnation granules, homogeneous granules, wettable powders, pastes, emulsions, solutions or aerosols.

For the production of solid processing forms (dust, litter, Granules) the active ingredient is mixed with solid carriers. The grain size the carrier material is expediently up to approx. 0.1 mm for dust and for grit approx. 0.075 to 0.2 mm and for granulates 0.2 mm or more The active ingredient concentrations in the solid forms of work-up, 0.5 to 80% are generally present. These mixtures The active ingredient can also be stabilized additives and / or nonionic anion-active and cation-active substances are added, which, for example, increase the oil strength Improve the active ingredient on plants and parts of plants (lubricants and adhesives) and / or better wettability (wetting agents) and dispersibility (dispersants) guarantee.

Active ingredient concentrates dispersible in Wassc.r, wettable powders (wettable powder), pastes and emulsion concentrates are agents that work with water can be diluted to any desired concentration. They ordered from active ingredient, Carrier material, optionally additives stabilizing the active substance, surface-active substances and antifoams and optionally solvents. The active ingredient concentration in these funds is 5-80%. The wettable powders and pastes are obtained by mixing the active ingredient with dispersants and powdery carriers mixed and ground in suitable devices until homogeneous. In some In some cases it is advantageous to use mixtures of different carriers. as Antifoam agents, for example, can be used with silicones, etc. The active ingredient will mixed, ground, sieved and strained with the additives listed above, that with wettable powders the solid part has a particle size of 0.02-0.04 and with pastes of 0.003 mm. For the preparation of emulsion concentrates and Pastes are used as dispersants, organic solvents, and water. the Solvents must be practically odorless, not phytotoxic, compared to the active ingredient inert and not easily flammable.

The agents according to the invention can also be used in the form of solutions be applied. for this purpose, the active ingredient of general formula I is suitable organic solvents, solvent mixtures or water. The solutions should contain the active ingredient in a concentration range of 1-20%.

Granules The following are used to produce 5% granules Substances used: 5 parts of active ingredient according to formula I, 0.25 part of epichlorohydrin, 0.25 Parts of cetyl polyglycol ether with 8 moles of ethylene oxide, 3.50 parts of polyglycol ("Carbowax" R), 91 parts of kaolin (grain size 0.3-0.8 mm).

The active ingredient is mixed in epichlorohydrin and made up of 6 parts Dissolved acetone, then polyglycol and cetyl polyglycol ether are added. The so The solution obtained is sprayed onto kaolin and then the acetone in vacuo evaporates :.

Spray powder For the production of a) 50%, b) 25% and c) 10% wettable powder, the following ingredients are used: a) 50 parts of active ingredient according to formula I 5 parts of sodium dibutylnaphthylsulphonate, 3 parts of naphthalenesulphonic acids-phenolsulphonic acids-formaldehyde condensate 3: 2: 1, 20 parts of kaolin, 22 parts of Champagne chalk; b) 25 parts of the above Active ingredient 5 parts of oleylmethyltauride sodium salt, 2.5 parts of naphthalenesulfonic acid-formaldehyde condensate 0.5 parts carboxymethyl cellulose, 5 parts neutral potassium aluminum silicate, 62 Parts of kaolin; c) 1.0 part e of the above-mentioned active ingredient 3 parts mixture of Sodium salts of saturated fatty alcohol sulfates, 5 parts of naphthalenesulfonic acid-formaldehyde condensate, 82 parts of kaolin.

The active ingredient indicated is based on the appropriate carriers (Kaolin and chalk) drawn up and then mixed and ground. You get Injection powder with excellent wettability and suspension properties. From such wettable powders By diluting with water, suspensions of any desired concentration of active substance can be created can be obtained. Such suspensions can be used to control weeds and Weed grasses are used in cotton plantings.

Paste The following substances are used to produce a 45% paste used: 45 parts of active ingredient according to the formula. I 5 parts of sodium aluminum silicate, 14 parts of cetyl polyglycol ether with 8 moles of ethylene oxide, 1 part of cetyl polyglycol ether with 5 moles of ethylene oxide, 2 parts of spindle oil, 10 parts of polyglycol (Carbowax®), 23 Share water.

The active ingredient is mixed with the additives in devices suitable for this purpose intimately mixed and ground. A paste is obtained from which, by diluting it make suspensions of any desired concentration with water.

Emulsion concentrate For the production of a 10% emulsion concentrate 10 parts of active ingredient according to formula I 15 parts of oleyl polyglycol ether with 8 mol Ethylene oxide, 75 parts of isophores (3,5,5-trimethylcyclohex-2-en-1-one) emulsions mixed. This concentrate can be mixed with water to form emulsions at suitable concentrations be diluted.

Such emulsions are suitable for the removal and mapping of common herbs in cultivated plants, such as soybeans and potatoes etc.

Claims (4)

Herbicidally active 1,2,4-triazin-5-one derivative P A T E N T A N S P R Ü C H E 1) 4-Amino-6- (2,2-dichloro-1-methyl-cyclopropyl) -3-methylthio 1,2.4-triazinon-5-one. 2) llericidal agent, characterized in that it is used as an active ingredient the compound according to claim 1 contains conventional auxiliaries in addition to. 3) Use of the compound according to claim 1 or those containing them herbicidal compositions for controlling weeds. 4) Process for the preparation of the compound according to claim 1, characterized characterized in that the compound of the formula H2N # NH # CS # NH # NH2 is known per se Way with (2.2-dichloro-1-metlrrlcyclopropyl) -glyoxylic acid or a reactive Reacts derivative of this acid and the reaction product in a manner known per se methylated.