CS236781B2 - Selective herbicide agent - Google Patents

Abstract

1. Selective herbicidal agents, characterised in that they contain an active compound combination consisting of (1) 4-amino-3-methyl-6-phenyl-1,2,4-triazin-5(4 H)-one (metamitron) of the formula I see diagramm : EP0086392,P17,F4 and (2) at least one substituted phenoxypropionic acid ester of the general formula II see diagramm : EP0086392,P17,F5 wherein R**1 represents hydrogen or methyl, R**2 represents hydrogen or methyl, n represents 1 or 2, X represents hydrogen, methyl, methoxy, halogen and/or nitro, a represents 1 or 2, Ar represents the radical see diagramm : EP0086392,P17,F6 or see diagramm : EP0086392,P17,F7 Y represents C1-4 -alkyl, halogen, trifluoromethyl, nitro and/or cyano and b represents 1, 2 or 3.

Description

The invention discloses novel herbicidal synergistic active compound combinations comprising, on the one hand, a preparation of Metamitron and, on the other hand, certain esters of phenoxypropionic acids, which compositions can be used particularly advantageously for the selective control of weeds in beet crops.

It is already known that 4-amino-3-methyl-6-phenyl-1,2,4-triazin-5- (4H) -one (common name Metamitron) can be used as a selective herbicide in beet cultures (see DE- OS No. 2,224,161). Metamitron, however, has only a weak effect against prossy grassy weeds.

It has now surprisingly been found that a novel active ingredient combination comprising 4-amino-3-methyl-6-phenyl-1,2,4-triazin-5 (4H) -one (Metamitron) of the formula I

and at least one substituted phenoxypropionic acid ester of formula II

in which X represents a hydrogen atom or a halogen atom and

R1 represents a hydrogen atom or a methyl group,

Ar represents a 2-pyridyl or phenyl group, which is optionally substituted by one or two halogen atoms or trifluoromethyl groups, exhibits a particularly high herbicidal activity.

Particularly preferred active compounds of the formula II are the following compounds:

ai ~ 5)

Surprisingly, the herbicidal activity of the active compound combination according to the invention is considerably higher than the sum of the effects of the individual active compounds. It is therefore an unexpected genuine synergistic effect and not just an effect addition. Beet cultures tolerate the new active ingredient combination as well as Metamitron (I), and the active ingredient combinations according to the invention can also be used to kill weeds which are highly problematic in their control, such as prosciatic grass weeds and deaf oats. The novel active compound combinations according to the invention thus represent a valuable enrichment of the prior art in the field of herbicides for application in beet crops.

The weeds which are generally found in beet crops and which can be reliably controlled by the active compound combinations according to the invention are:

dicotyledonous weeds of genera:

mustard (sinapis), watercress (Lepidiumj, bedstraw (Galium), chickweed (Stellaria), chamomile (Matricaria), chickweed (Anthemis), five-flowered (Galinsoga), goosefoot (Chenopodium), nettle (Urtica), ragwort (Senecio), amaranth (Amaranthus), purslane (Portulaca), beetroot (Xanthium), bindweed (Convolvulus), broom (Ipomoea), moss (Polygonum), gathering (Sesbania), ambrosia (Ambrosia), thistle (Cirsium), thistle (Carduus), milk (Sonchus), Eggplant (Solanum), Grain (Rorippa), Rotala, Lindernia, Dead-nettle (Lamium), Speedwell (Veronica), Abutilon (Abutilon), Emex, Durman (Datura), Violet (Viola), Hemp (Galeopsis), poppy (Papaver), cornflower (Centaurea);

monocotyledonous weeds of genera:

hedgehog (Echinochloa), shear (Setaria), millet (Panicům), tree frog (Digitaria), timothy (Phleum), meadow-grass (Poa), fescue (Festuca), eleusine (Eleusie), Brachiaria, rye (Lolium), brome (Bromus) ), oats (Avena), plush. (Cyperus), Sorghum, Agropyron, Cynodon, Monochoria, Fimbristylis, Sagittaria, Eleocharis, Scirpus, Paspalum, Ischaemum, Sphenoclea, Dactyloctenium, distemper, Agrostis, chundella (Apera).

However, the use of the active compound combination according to the invention is by no means limited to these genera, but applies as already; As mentioned above, the active compound combinations according to the invention exhibit an excellent action against dicotyledonous and grassy weeds, in particular against sieve grasses, with very good tolerability for beet cultures. Thus, these combinations can be particularly advantageously used as selective herbicides in beet culture.

The synergistic effect of the active compound combination according to the invention is particularly high in a certain concentration range of the individual components. However, the weight ratios of the individual active compounds in the combinations according to the invention can be varied within wide limits. In general, from 1 to 1 part by weight of active compound of the formula I is from 0.01 to 10 parts by weight of active compound of the formula II.

The active compound combinations according to the invention can be converted into the customary formulations such as solutions, emulsions, wettable powders, suspensions, powders, dusts, pastes, soluble powders, granules, concentrates based on suspensions and emulsions, natural and synthetic substances impregnated with active substances and small particles coated with polymeric substances.

These compositions are prepared in a manner known per se, for example by mixing the active compounds with fillers, i.e. liquid solvents and / or solid carriers, optionally with surfactants, i.e. emulsifiers and / or dispersants and / or foaming agents.

If water is used as a filler, it is also possible to use, for example, organic solvents as co-solvents. Basically suitable liquid solvents are: aromatics such as xylene, toluene or alkylnaphthalenes, chlorinated aromatics or chlorinated aliphatic hydrocarbons such as chlorobenzenes, chlorethylenes or methylene chloride, aliphatic hydrocarbons such as cyclohexane or paraffins, for example 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, strongly polar solvents such as dimethylformamide and dimethyl sulfoxide, and water.

Suitable solid carriers are, for example: natural stone meal, such as kaolins, alumina, talc, chalk, quartz, attapulgite, montmorillonite or diatomaceous earth, and synthetic stone meal, such as highly disperse silica, alumina and silicates. Suitable solid carriers for the preparation of granulates are, for example, crushed and fractionated natural stone materials such as limestone, marble, pumice, sepiolite and dolomite, as well as synthetic granules of inorganic flours and organic granules such as sawdust, coconut shells, corn sticks and tobacco stems. Suitable emulsifiers and / or foaming agents are non-ionic and anionic emulsifiers, such as polyoxyethylene fatty acid esters, fatty alcohol polyoxyethylene ethers, for example alkyl aryl polyglycol ether, alkyl sulfonates, alkyl sulfates, arylsulfonates and protein hydrolysates, and methyl dispersants such as lignin, sulfite, sulfite.

The compositions of the invention may include adhesives such as carboxymethylcellulose, natural and synthetic powdered, granular or latex polymers such as gum arabic, polyvinyl alcohol and polyvinyl acetate.

Further, these compositions may contain coloring agents such as inorganic pigments, for example iron oxide, titanium dioxide and ferrocyanide, and organic dyes such as alizarin dyes, azo dyes and metal phthalocyanine dyes, as well as trace elements such as iron, manganese, boron, copper, cobalt, bolybdenum and zinc.

The concentrates generally contain between 0.1 and 95% by weight of the active compound combination, preferably 0.5 to 90% of the combination.

The active compound combinations according to the invention are generally used in the form of ready-to-use compositions. However, the individual active ingredients contained in these combinations can also be mixed in the form of separate preparations, e.g. apply these; substances such as so-called tankmix prepared immediately prior to application.

The novel active compound combinations according to the invention can be used as such or in the form of compositions, even in admixture with other known herbicides used in beet cultures, which known herbicides can be present in the ready-to-use compositions according to the invention or of the invention, or with compositions containing them, to be mixed prior to application (tankmix). The active compound combinations according to the invention can furthermore be mixed with other known active compounds, such as fungicides, insecticides, acaricides, nematocides, avian influenza preservatives, growth agents, nutrients for. plants and soil conditioners. For certain application purposes, it may further be advantageous to add to the compositions, as other ingredients for plant compatible mineral or vegetable oils (for example, the commercial formulation "Sun").

Or ammonium salts such as ammonium sulfate or ammonium rhodanlde.

The active compound combinations according to the invention can be applied as such, in the form of concentrated formulations or from further dilution forms prepared therefrom, such as ready-to-use solutions, suspensions, emulsions, powders, pastes and granules. Application is carried out in the usual manner, for example by watering, spraying, dusting, tossing, etc.

The consumption of the active compound combinations according to the invention can vary within certain limits and depends, inter alia, on weather and soil conditions. In general, these rates are between 0.01 and 15 kg of active ingredient combination per hectare, preferably between 0.05 and 10 kg / ha.

The active compound combinations according to the invention can be applied both before and after emergence of the plants. Preferably, the application is carried out after emergence of the plants, i.e. post-emergence.

The following examples demonstrate the good herbicidal activity of the novel active compound combinations. While there are weaknesses in the herbicidal activity of the individual active ingredients, the combinations according to the invention exhibit a very broad weed control which is greater than the sum of the effects of the individual active ingredients in the combination.

A synergistic effect on herbicides is always mentioned if the herbicidal effect of the active compound combination is higher than the sum of the effects of the separately applied active compounds.

The expected effect for a given combination of two herbicides can be calculated as follows (see S. R. Colby, "Calculating synergistic and antagonistic responses of herbicide combinations", Weeds 15, 20-22, 1967):

X =% damage by herbicide A applied at p kg / ha,

Y = damage in ° / o herbicide V applied at q kg / ha a

E1 = expected damage to herbicides A and В applied at doses p and q kg / ha,

If the actual damage is higher than the calculated damage, the combination has a greater than the cumulative effect and thus shows a synergistic effect.

The following examples show that the herbicidal effect of the active compound combinations on the weeds found is higher than that calculated, and that the new active compound combinations act synergistically.

The active compound combinations according to the invention also show, in part, side effects against soil insects, as well as a systemic action against Pyricularia oryzae on rice, which is ascribed to the activity of the component of the formula II.

Example A

Efficacy test for post-emergence solvent application:

parts by weight of acetone emulsifier:

part by weight of alkylaryl polyglycoether

To prepare a suitable active ingredient, 1 part by weight of the active ingredient is mixed with the indicated amount of solvent, the indicated amount of emulsifier is added and the concentrate is diluted with water to the desired concentration.

The prepared active ingredient is sprayed with 5 to 15 cm high test plants to achieve the consumption of active ingredient per unit area shown in the table. The concentration of the spraying agent is selected such that the amount of active substances given in the table is applied in 2000 liters of water per hectare. After three weeks, the plant damage was evaluated in% compared to that of the untreated control plants. % / O means no effect (as in untreated control plants)

100% complete destruction of plants

The active substances, the active substance consumption and the results obtained are shown in the following table А. In this table, the abbreviations and symbols have the following meanings:

vyp =% damage calculated according to Colby's formula nal = found damage% (I) = Metamitron The other active substances are designated with the same numbers as in the examples below.

Table А

Test of efficacy in post-emergence application (greenhouse experiment) Active substance or consumption (kg / ha) Efficiency in% Combination of sugar beet Digitaria Setaria Echinochloa Off off Off off o o o o M CO M> CO LO

O O Mi

О MlОО CO Ml СО Ю

O o o 00 o 00 o o o o o r o r o o o o o o o r r o o o o o o o o o o o o o o

O Ю Ю Ю CD) O) O) CD

CM O CM CM CM LO CO LO LO Ю

O O LO O LO O) 00 00 00 O)

LO LO LO LOLO

CM CM CM CMCM

^ RH r-- t tH rH rH ^

CD CD CD CD CD

LO LO Ю LO LO CM CM CM CM rH rH rH rH rH ^ o CD o cd cd + + + + + oq ^ OO 00 00 _fc cm cm cm cm cm

Д

N

Íh CM co 5 ¹ · · i 1Д ·

Ф + + + + +

Ό

O h _M μ η m

LH »x — t x— <

rH CM OQ д д Д t— <<* - <> - <

Example В

Test for efficacy in post-emergence application // field experiment solvent:

parts by weight of acetone emulsifier:

part by weight of alkylaryl polyglycol ether

To prepare a suitable active ingredient, 1 part by weight of the active ingredient is mixed with the indicated amount of solvent, the indicated amount of emulsifier is added and the concentrate is diluted with water to the desired concentration.

The plots on the test plot, on which the test plants in the 2 to 3 leaf stage are grown, are sprayed with an amount of active agent sufficient to wet the plants uniformly. The decisive factor is the consumption of active substance per unit area. After 35 days, the plant damage was evaluated in% compared to that of the untreated control plants. % / O means no effect (as in untreated control plants)

100 ° / o complete destruction of plants.

The active substances, the active substance consumption and the results obtained are shown in the following table. In this table, the abbreviations and symbols have the following meanings:

vyp =% damage calculated according to Colby's formula nal - damage found in% (I) - Metamitron other active substances are identified by the same numbers as in the examples below.

Post-emergence efficacy test (field trial)

Active substance or consumption efficiency in% combination (kg / ha) Beet Chemopodium Polygons Echinochloa poured off poured off

LO Ю Ю гН '' Ф Ю

OJ Ю CD

lo LO Ю О О LO о о нН т — 1

LO LO о о ю ю о θ ' о оГ О CD θ 'θ' 4 — Н О CD of

'N ω S д> 4>

4- 4-ω

Л д '2 нн нч Д

The active compound of the formula I is known (cf. DE-OS No. 2,224,161 and U.S. Pat. No. 3,847,914). The active compounds of the formula II are described in European Patent Application No. EP-A2-0 068 260, published January 5

Thus, at the priority date of the present invention, these compounds were not known.

Active substances of the formula II

CW ₃

O-CH-CO-CH-CH-O- _CH10

in which

R ¹ , X and Ar are as defined above, may be obtained by either (a) compound of formula III

Ar-O

(lil) in which

M represents a hydrogen or alkali metal atom; and

Ar is as defined above, reacted with a compound of formula IV ⁵⁰ⁱ

From * -CH- с-о-сн-сн _г -о-сн _г А ^ у (I V) in which

Z ¹ represents a halogen atom and

R ¹ and X are as defined above, or (b) a compound of formula V is CH ₃ O

Ar-O-CH 2 -O-CH-CZ ² (V) wherein

Z ² represents a hydroxy group or a halogen atom and

Ar is as defined above, reacted with a compound of formula VI

HO-CH-CH 2 O-CH.

(VI) in which:

R ¹ and X are as defined above.

If, for example, the sodium salt is used as starting material for the purposes of variant (a)

4- (3,5-dichloro-2-pyridyloxyphenol) and 2- (2-fluorobenzyloix) ethyl 2-brampropionate, the reaction may be described as follows:

CH. O ^J II

6r-CH-C-0- (CH) -O-CH _of

F

-----—

- Hd.Br

Ct

When used according to variant (bj) as starting materials, for example 2- (4- (5-trifluoromethyl-2-pyridyloxy) phenoxy] propionyl chloride and 1- (4-chlorobenzyloxy) -2-pro panol, describe the course of the reaction as follows:

CHj o CMj

O-? Y-O-CH-C-Cl + HO-CHCH? O-CH?

[bz-zaTI

-HCI

ci-ij o f

G-С-С-О-СНС ^ О-СЧ ^

Preferably, both processes described above are carried out in the presence of a diluent. Suitable diluents are water and inert organic solvents, for example optionally chlorinated hydrocarbons such as benzene or chloroform, ethers such as dioxane and tetrahydrofuran, nitriles such as acetonitrile, sulfones and sulfoxides such as dimethylsulfoxide or sulfolane, and tertiary bases such as pyridine.

Both processes are preferably carried out in the presence of an acid binding agent. In this case, all customary acid acceptors, such as alkali metal hydroxides, carbonates, bicarbonates and alkoxides, or tertiary amines, such as triethylamine, diethylanine or pyridine, are suitable.

The reaction temperatures for both processes can be varied within wide limits. In general, it is operated at a temperature between -20 ° C and the boiling point of the reaction mixture, preferably at a temperature between 0 ° C and 100 ° C.

In practice, both starting materials are generally employed in approximately equimolar amounts. The acid binding agent is used in a stoichiometric amount or in excess of up to three times the stoichiometric amount.

The work-up and isolation of the reaction product of the general formula (II) are carried out in a conventional manner.

The invention is illustrated by the following non-limiting examples.

Example 1

Variant A)

Ct

CH o

I u

O-CH ~ C ~ O4CH ^ O ~ CH (11-1)

F

A mixture of 30.6 g of 4- (3,5-dichloro-2-pyridyloxy) phenol sodium salt and 36 g of 2-bromo-propionic acid 2- (2-fluoro-benzyloxy) -ethyl ester (IV-1) in 100 ml of dimethylformamide was heated under heating for 3 hours. The reaction mixture is poured into 300 ml of water and extracted with ether, the ether phase is washed first with 1% sodium hydroxide solution and then with water, dried and the ether is distilled off. give 38 g of desired ¹ 2- {2-fluorobenzyloxy) ethyl 2- [4- (3,5-dichloro-2-pyridyloxy) fenoxyJpropionové acid (II-l), mp 54-57 ° C.

Example 2

Variant A)

The product has a refractive index n _D ²⁰ - 1.5803.

Example 3

Variant A)

In analogy to Example 1, the reaction of 4- (3,5-dichloro-3-pyridyloxy) phenol sodium salt with 2- (4-chlorobenzyloxy) ethyl 2-bromopropionate (IV-6) affords 2- (4-chlorobenzyloxy) 2- (4- (3,5-Dichloro-2-pyridyloxy) -phenoxy] -propionic acid ethyl ester (II-2).

1>

A mixture of 25.4 g of 4- (4-trifluoromethylphenoxy) phenol, 28.7 g of 2-bromopropionic acid 2-benzyloxyethyl ester (IV-2) and 14.5 g of anhydrous potassium carbonate in 150 ml of dry acetonitrile is heated with stirring for 4 hours. After refluxing, acetonitrile was distilled off under reduced pressure, and toluene was added to the residue, followed by treatment analogously to Example 1 to give 2- (4- (4-trifluoromethylphenoxy) phenoxy) propionic acid 2-benzyloxyethyl ester ( II-3) with refractive index n _D ²⁰ = 1.5200.

Example 4

Variant A)

In analogy to Example 1, the reaction of 4- (3,5-dichloro-2-pyridyloxy) phenol sodium salt with 2-benzyloxyethyl 2-bromopropionate (IV-2) affords 2- (4- (3,5-dichloro-2-benzyloxyethyl) ester). 2-pyridyloxy) (enoxy) propionic acid (II-4), m.p.

Example 5

Variant (b)

16.6 g of 1-benzyloxy-2-propanol and 10.6 g of triethylamine are dissolved in 200 ml of toluene, the solution is cooled to 0 ° C and a solution is added dropwise with stirring at 0-5 ° C.

34.7 g of 2- [4- (3,5-dichloro-2-pyridyloxy) phenoxy] propionyl chloride in 80 ml of toluene. The reaction mixture was then slowly heated to 40-50 ⁰ C. а к complete reaction was stirred for 1 h. After an analogous treatment, as in Example 1 to give 2-benzyloxy-l-methyl ethyl 2- (4- (3,5-dichloro-2-pyridyloxyjfenoxy] propionic acid as a viscous oil of refractive index n _D ²⁰ = 1.5710. Yield 43.4 g.

The compounds of the following Table I and corresponding to formula II can also be obtained in an analogous manner.

Table I

Compound number

Ar

R ¹ X physical constants

11-11

11-12

11-13

11-14

11-15

ct

Η H n _D ²⁰ = 1.5322

H n _D ²⁰ = 1.5518

H n _D ²⁰ = 1.5696

H n _D ²⁰ == 1.5397

H n _D ²⁰ = 1.5260

H 2-F n _D ² ® = 1.5235 H 4-F n _D ² ° '= 1.5214 H 2-C1 n _D ² <> = ' 1.5360 H 4-C1 n _D ² ® = 1.5360 H 4-C1 n _D ² ® = 1.5380

Compound number Ar R1 X physical constants 11-16 C _F ^ct H 4-C1 n _D 20 = 1.5450 11-17 ^F O H 4-C1 n _D 20 = 1.5559 11-18 γ H 4-Br no20 = 1.5450 and  / 11-19  ccTV Mj H 2-C1 mp 64-66 ° C 11-20 ... ct ^ř --6- H 4-Br n _D 20 · =. 1,5870 11-21 H 2-C1 n _D 20; 1.5349 11-22 H 4-Br n _D 20 ==! 1.5440 Π-23 ^CFi ~ H H Mp 44-47 ° C 11-24 H 4-C1 n _D 20; 1.5350 11-25 ^cf ^> CHs H Пц20 = 3i 1.5224 11-26 H 2-F mp 46-48.5 ° C

23G781 IV-1

Preparation of starting materials of formula IV

A solution of 17.5 g of 2- (2-fluorobenzyloxy) ethanol and 10.6 g of triethylamine in 150 ml of toluene is cooled to -5 ° C and a solution is added dropwise with stirring at -5 ° C to 0 ° C.

21.6 g of 2-bromopropionyl bromide in 30 ml of toluene. The reaction mixture was stirred at room temperature for 2 hours, then washed sequentially with 1% sodium hydroxide solution and water. The toluene solution was dried and filtered and the toluene was distilled off under reduced pressure. 28.2 g of 2-bromopropionic acid 2- (2-fluorobenzyloxy) ethyl ester (IV-1) having an intex of refraction n _D 20 = 1.5038 are obtained.

In a similar manner, the compounds corresponding to formula IV are summarized in Table II below:

C / ¹ QR ¹

Z-CO-CH-CH = CH - O-CH _of

T a b u 1 k а II

compound number From ¹ R ^{1 *} X physical constants IV-2 bi- H H n _n 205 = 1.5182 IV-3 whose H 4-F n _D 20 = 1.5004 IV-4 Br H 4-F n _D ²⁰ = 1.5040 IV-5 Br H 2-C1 n _D ^{20 -5} = 1.5302 IV-6 Br H 4-C1 n _D 20 = 1.5269 IV-7 Cl H 4-Br n _D 20.5 = 1.5321 IV-8 Br H 4-Br n _D ²⁰ · ⁵ = 1.5434 IV-9 Br СНз H n _D 20.5 = _{1> 51 °} o

Claims (6)

CLAIMS 1. Selective herbicidal composition, characterized by 4-amino-3-methyl-6-phenyl-1,2,4-triazine-5 (4H), characterized in that it comprises a combination of active ingredients consisting of: at least one substituted phenoxypropionic acid ester of formula II CH. _R 1 i - ³ i O-CH-C-O-CH-CHrO-CH. no O in which R ¹ represents hydrogen or methyl, X is hydrogen or halogen; and Ar represents a 2-pyridyl or phenyl group optionally substituted by one or two halogen atoms or trifluoromethyl groups, the weight ratio of active compound of formula I to active compound of formula II being from 1: 0.01 to 1: 10. 2. A composition according to claim 1, wherein the active ingredient is a combination of 4-amino-3-methyl-6-phenyl-1,2,4-triazin-5 (4H) -one of formula I and a compound of formula II-1 in the above weight ratio. 3. A composition according to claim 1 which comprises as active ingredient a combination consisting of 4-amino-3-methyl-6-phenyl-1,2,4-triazin-5 (4H) -one of formula I and a compound of formula II-2 Cl in the above weight ratio. 4. A composition according to claim 1, wherein the active ingredient is a combination consisting of 4-amino-3-methyl-6-phenyl-1,2,4-triazin-5 (4H) -one and a compound of formula Β-3 in the above weight ratio. 5. A composition according to claim 1 which comprises as active ingredient a combination consisting of 4-amino-3-methyl-6-phenyl-1,2,4-triazin-5 (4H) -one of formula I and a compound of formula II- 4 Cl in the above weight ratio. 6. A composition according to claim 1, wherein the active ingredient is a combination of 4-amino-3-methyl-6-phenyl-1,2,4-triazin-5 (4H) -one of formula I and a compound of formula II-5