CS248710B2 - Herbicide agent with encreased selectivity in the growth of maize and millet and production method of the effective compound - Google Patents

Abstract

Herbicidal agent with increased selectivity in corn and millet-based stands the alkylammonium salts of 3,5-dibromo-4-hydroxybenzonitrile, characterized in that it comprises trimethylammonium as active ingredient and / or triethylammonium salt of 3,5- -dibromo-4-hydroxybenzonitrile and acceptable a diluent or surfactant. Described it is also a method of producing the active ingredient.

Description

The present invention relates to a novel herbicidal composition for use in maize and millet crops.

For example, it is known from British Patent Nos. 1,030,249 and 1067,032 that 3,5-dibromo-4-hydroxybenzonitrile, hereinafter referred to as "bromoxynil" and its esters and salts with alkali metals, alkaline earth metals, ammonium salts and salts with amines have valuable herbicidal properties, particularly with respect to selective control of dicotyledonous weeds in cereals when applied after emergence. This term refers to the application to the aerial parts of dicotyledonous plants after they have emerged above the soil surface.

Bromoxynil has been widely used as a herbicide for many years, predominantly using its octanoate or its alkali metal salt, particularly the potassium salt, especially for the selective control of dicotyledonous weeds in emerging cereals.

Bromoxynil esters, in particular octanoate, are commonly used after emergence against dicotyledonous weeds in small grain cereal crops such as wheat, barley and oats, which provide good weed control without major damage to the cereals. However, the use of bromoxynloctanoate after emergence against dicotyledonous weeds in broad-leaf cereal stands, particularly in maize (Zea mays) and millet (Sorghum bicolor), is limited due to the transient phytotoxicity, which is manifested as necrosis of the crop sprayed leaves. The safety margin between the amount of bromoxyniloctanoate to be used to effectively control dicotyledonous weeds and the amount of this substance that causes maize and millet damage is very narrow. Bromoxyniloctanoate therefore has a low selectivity index, meaning the ratio between the amount of herbicide that the crop tolerates and the amount that must be used to satisfactorily control weeds. Therefore, weed control in maize and millet after emergence cannot be recommended. Strangely, in contrast to this property in maize and millet crops, bromoxyniloctanoate has a high selectivity when used as a herbicide in small grain cereal crops such as wheat where it has been successfully used for many years.

Alkali metal bromoxynil salts, especially the potassium salt of this substance, are well tolerated in crops of small grain and maize and millet at much higher doses than bromoxyniloctanoate, but the effect of these substances on dicotyledonous weeds is significantly lower than effect of bromoxyniloctanoate. For this reason, the potassium salt itself has never been widely used to control weeds in cereals, although it has often been used in admixture with other herbicides in herbicidal weed control environments in small grain cereal stands.

Thus, it is clear that neither of the two bromoxynil derivatives that have been used to date to reduce dicotyledonous weed growth in small grain cereal stands, namely bromoxynil octanoate and bromoxynil sodium, can be used to routinely control dicotyledonous weed growth in maize or millet.

Some bromoxynil 3-amine salts have also been described as herbicides, but until now none of these salts have been widely used in agriculture.

It has now been unexpectedly found in further experiments that bromoxynil salts with trimethylamine and especially triethylamine are far more effective at controlling the growth of dicotyledonous weeds than bromoxynil potassium and at the same time far less damaging maize (Zea mays) and millet (Sorghum bicolorj) than bromoxyniloctanoate. and in particular the triethylammonium salt has a much broader selectivity index and selectivity threshold than bromoxynil octanoate in limiting dicotyledonous weed growth when applied after emergence in maize and millet crops, and are much more effective for this use than bromoxynil potassium salt, i.e. their use means great progress in controlling dicotyledonous weeds in maize and millet crops, and trimethylammonium and trlethylammonium salt is also far more effective in controlling dicotyledonous weeds in maize and dew emerging at a wider selectivity threshold than other bromoxynil salts tested for this purpose, namely bromoxyniltriethylanolammonium, tri-n-propylammonium, tri-n-butylammonium, methyl-di-n-octylammonium salt and ammonium salts. Trimethylammonium and triethylammonium salts of bromoxynil, in particular triethylammonium salts, are readily compatible with maize (Zea mays) and millet (Sorghum bicolorj in an amount of in particular 100 to 1000 g / ha after emergence, particularly 150 to 600 g / ha after emergence, thereby achieving a satisfactory Suppressing the growth of dicotyledonous weeds when applied after emergence The amount of each substance per hectare is always 'pe', the so-called phenyl equivalent, expressed as bromoxynil content in trimethylammonium or triethylammonium salt or in any other bromoxynil derivative that is listed.

Accordingly, the present invention provides a herbicidal composition with increased selectivity in maize and millet crops based on 3,5-dibromo-4-hydroxybenzonitrile alkylammonium salts, characterized in that it contains, as an active ingredient, trimethylammonium and / or triethylammonium salt of 3,5-dibromo-4. hydroxybenzonitrile and an acceptable diluent or surfactant. The present invention also relates to a process for the preparation of an active ingredient which comprises reacting a stoichiometric amount of 3,5-dibromo-4-hyd24871-roxybenzonitrile and trimethylamine or triethylamine in a suitable solvent, for example water, glyicols, tetrahydrofurfuryl alcohol, acetophenone, cyclohexanone, isopforone, toluene, xylene, animal, vegetable or mineral oil, aliphatic alcohol or acetone.

The composition according to the invention is applied after emergence to dicotyledonous weeds in maize or millet crops in a herbicidally effective amount which, however, still does not cause permanent damage to the crop with trimethylammonium or triethylammonium bromoxynil salt, in particular 100-1000 g pe / ha and 600 g pe / ha. Trimethylammonium and triethylammonium salts are particularly useful for controlling dicotyledonous weeds such as Abutilon theophrasti, Amaranthus spp, for example Amaranthus retroflexus, Ambrosia artemisiifolia, Amsinkia intermedia, Anthemis cotula, Brassica spp., Brassica spp. Capsella bursa-pastoris, Centaurea cyanus, Chenopodium album, Chorispora tenella, Datura stramonium, Descurainea sophia, Fagopyrum tertaricum, Galinsoga parviflora, Helianthus annuus, Ipomea spp., E.g. Matrixaria recutita, Matrixaria Inodora, Myosotis arvensis, Papaver rhoeas, Plantago media, Polygons spp., For example Polygons aviculare, Polygons persicaria, Polygons pensylvanicum and Polygons scabrum, Portulaca oleracea, Raphanus raphanistrum, Senecosa vulgaris, Sida spinosa, Sida Solanum nigrum, Solanum elaeagnifolium, Sonchus asperus, Sonchus oleracea, Thlaspi arvense, Veronica persica and Xanthium spp., for example, Xanthium strumarium, Xanthium pensylvanicum and Xantium canadensis in emerging maize and millet crops, in particular to suppress the growth of Abutilon Chenopodium, Amaranth retrousea, Amaranth, Polygonum lapathifolium, Solanum nigrum and Xanthium strumarium, their presence is particularly difficult in maize and millet crops.

Obviously, a mixture of trimethylammonium or triethylammonium salts of bromoxynil in any ratio can also be used to control dicotyledonous weeds.

The trimethylammonium or triethylammonium salt may be used as such to suppress dicotyledonous weed growth in maize or millet after emergence, or may be used to suppress dicotyledonous weed growth in maize or millet after growth together with other herbicides that suppress monocotyledon weed growth , for example grasses and / or together with substances which are herbicidally active against other types of weeds and / or which have a permanent herbicidal effect and which are well tolerated in maize and millet crops. These are mainly substances that are applied to the soil containing weed seeds or their seedlings before weeds rise above the soil surface. Suitable herbicides for use herein are, for example:

atrazine [2-chloro-4-ethylamino-6-isopropylamino-1,3,5-triazine], simazine [2-chloro-4,6-bis (ethylamino) -1,3,5-triazine], cyanazine [2- (4-chloro-6-ethylamino-1,3,5-triazin-2-ylamino) -2-methylpropionitrile] prazazine [2-chloro-4,6-bis- (isopropylamino) -1,3,5 -triazine], terbutylazine [2-tert-butylamino-4-chloro-6-ethylamino-1,3,5-triazine], linuron [3- (3,4-dichlorophenyl) -1-methoxy-1-methylurea] ], isoproturon [3- (4-isopropylphenyl) -1,1-dimethylurea], dinosebacetate [2-sec-butyl-4,6-dinitrophenylacetate], dinosebamine [lalkanoylammonium salts of 2-sec-butyl-4,6-dinitrophenol] ], dicamba [3,6-dichloro-2-methoxybenzoic acid], dinoterb [2-tert-butyl-4,6-dinitrophenol] and their salts with metals such as sodium or potassium salts or with amines such as dimethylamine, phenoxyacetic acid herbicides such as 2,4-D [2,4-dichlorophenoxyacetic acid], and

MCPA [2-methyl-4-chlorophenoxyacetic acid] and salts thereof with metals such as sodium or potassium salts or with amines such as monomethylamine, dimethylamine, isopropylamine or triethylamine, or salts with altkanolamines such as diethanolamine, triethanolamine or mixed salts with isopropanolamines or low volatility esters thereof, for example their esters with butoxyethanol, propylene glycol, tetrahydrofurfuryl alcohol, butoxypropanol, ethylhexanol and isooctanol.

Bromoxyniltrimethylammonium and bromo248710 xyniltriethylammonium salts can be used singly or in admixture with the above herbicides to control the growth of dicotyledonous weeds in maize and millet crops after weed and crop emergence. If desired, bromoxyniltrimethylammonium, and bromoxyniltriethylammonium salt may be applied after sowing the crop with maize or millet and after incorporation into the soil of any of the following herbicidal agents:

alachlor [2-chloro-2 ', 6 ^<diethyl-N- (methoxymethyljacetanilid], metolachlor [2-chloro-6'-ethyl-N- (2-methoxy-l-methylethyl) aceto-toluidide], peodimethalin [N- (1-ethylpropyl) -2,6-dinitro-3,4-xylidine] butylate (S-ethyl-di-isobutylthiocarbamate), vernolate (S-propyldipropylthiocarbamate),

ETPC (S-ethyldipropylthiocarbamate) or

EPTC and N, N-diallyl-2,2-dichloroacetamide 12: 1.

When used to control dicotyledonous weed growth, bromomethyl and triethylammonium bromomethyl salt is used in the form of a herbicidal composition comprising at least one of the above bromoxynil salts in association with one or more acceptable diluents or mosquitoes, preferably in a homogeneous dispersion in surfactants may also be used in the preparation of the herbicidal composition. These are diluents, carriers and surfactants which are commonly used in the art and do not interfere with the effect of the bromoxyniltrimethylammonium and bromoxyniltriethylammonium salts. The term homogeneous dispersion in this case also encompasses the case in which the trimethyl ammonium or bromoxynil triethylammonium salt is dissolved in the other components of the herbicidal composition. The term herbicidal composition includes not only a composition which is ready for use, but also a concentrate which must be diluted before use. Preferably, the composition comprises 0.05 to 90% by weight of the trimethylammonium or triethylammonium salt of bromoxynil or a mixture thereof.

The herbicidal composition may contain a diluent or carrier and a surfactant, for example a wetting agent, dispersing agent or emulsifying agent. The surfactants which may be present in the herbicidal composition of the invention may be of the ionic or nonionic type, for example, sulforicinoleate, quaternary ammonium derivatives, products based on ethylene oxide condensates with alkylphenols, for example nonylphenol, octylphenol or polyarylphenol, or carboxylic acid esters with anhydrosorbitols whose solubility has been increased by etherification of free hydroxyl groups by condensation with ethylene oxide; it can also be alkali metal and alkaline earth metal salts with sulfuric acid and sulfonic acid esters such as sodium dinonylsulfosuccinate and sodium dioctylsulfonosuccinate; o alkali metal and alkaline earth metal salts with high molecular weight sulfonic acid derivatives, such as sodium or calcium lignosulfonate; and sodium and calcium alkylbenzene sulfonate.

The herbicidal compositions may contain from 0.01% to 10% by weight of the surfactant, if necessary even higher amounts of surfactant, for example up to 15% by weight, in the liquid emulsifiable concentrate in the suspension and up to 25% in the water-soluble liquid concentrate.

Examples of suitable solid diluents or carriers include aluminum silicate, talc, calcined magnesium oxide, gypsum, calcium phosphate, powdered cork, carbon black, and clays such as kaolin and bentonite. The solid composition, which may be in the form of a dust, granule or wettable powder, is preferably prepared by grinding the bromoxyniltrimethylammonium and bromoxyniltriethylammonium salt with a solid diluent or impregnating the solid diluent or carrier with a solution of bromoxyniltrimethylammonium and bromoxyniltriethylammonium solvent in a volatile solvent. and optionally, grinding the resulting product into a powder. Granular compositions may be obtained by absorbing bromooxyniltrimethylammonium and bromoxyniltriethylammonium salts in solution in a suitable solvent to a solid diluent or carrier in granular form and optionally removing excess solvent, for example by evaporation, or granulating the compositions obtained as above in powdered form. Solid herbicidal compositions, in particular wettable powders and granules, may contain a wetting agent or dispersing agent, for example of the above type, and may also serve as a diluent or carrier in the case of a solid composition.

The liquid compositions may take the form of aqueous solutions, solutions in an organic solvent or a mixture of water and an organic solvent, as well as a suspension or emulsion, optionally containing a surfactant. Suitable liquid diluents for these compositions are, for example, water, glycols, tetrahydrofurfuryl alcohol, acetophenone, cyclohexanone, isophorone, toluene, xylene and mineral, animal and vegetable oils, for example light aromatic and naphthenic oil fractions and mixtures of these solvents. Surfactants useful in liquid formulations may be of the ionic or non-ionic type, and may, in the case of liquid formulations, also serve as diluents or carriers.

Wettable powders, dispersible granules and liquid concentrate formulations may be diluted with water or other suitable diluent, for example, mineral or vegetable oils, particularly in the case of liquid concentrates in which the diluent or carrier is an oil, to form the compositions ready for use. If desired, liquid formulations containing bromoxyniltrimethylammonium and bromoxyniltriethylammonium salts (in the form of emulsified concentrates containing the active ingredient dissolved in the emulsifying agent or in the solvent containing the emulsifying agent, can be used, to which water is added immediately to form the compositions immediately). for use.

Liquid concentrates in which the diluent or carrier is an oil may be used without further dilution for electrostatic spraying.

The herbicidal compositions may also optionally contain conventional adjuvants such as adhesives, protective colloids, thickeners, penetration enhancers, stabilizers, sequestering agents, caking agents, colorants and corrosion inhibitors. These excipients may also serve as carriers or diluents.

Preferred herbicidal compositions are wettable powders containing 10 to 90% by weight of trimethylammonium or triethylammonium salt of bromoxynil, 2 to 10% by weight of surfactant and 10 to 88% by weight of solid diluent or carrier, and liquid, water-miscible concentrates containing 5% by weight. up to 50 percent (w / v) of trimethylammonium or triethylammonium bromoxynil salt, 5 to 25% (w / v surfactant) and 25 to 90% by volume of a water-miscible solvent such as dimethylformamide or a miscible solvent mixture with water and water, granules containing 1 to 90% by weight of trimethylammonium or triethylammonium salt of bromoxynil, 0.5 to 2.5% by weight of surfactant and 7.5 to 98.5% by weight of granular carrier, and emulsifiable concentrates, 0.05 to 90% (w / v), preferably 1 to 60 % trimethylammonium or triethylammonium salt of bromoxynil, 0.01 to 10%, preferably 1 to 10% (w / v) surfactant, and 9.99 to 99.94, preferably 39 to 98.99% by volume organic solvent.

The herbicidal compositions may also contain bromoxyniltrimethylammonium and bromoxyniltriethylammonium salts together with one or more other herbicides, preferably in a homogeneous dispersion, to be compatible with the trimethylammonium salt or the triethylammonium salt of bromoxynil, and optionally containing other such diluents or carriers, surfactants substances and common auxiliary slats of the above type.

Bromoxyniltriethylammonium and bromoxyniltrimethylammonium salts may be obtained by reacting a stoichiometric amount of bromoxynil and trimethylamine or triethylamine in a suitable inert solvent, for example a liquid diluent suitable for incorporation into the liquid herbicidal composition of the invention, optionally in a solvent mixture or a lower aliphatic alcohol a mixture of trimethylamine and triethylamine, a bromoxyniltrimethylammonium or bromoxyniltriethylammonium salt or a mixture of these salts can be isolated from the reaction mixture by conventional means, for example by filtration, optionally after partial or complete removal of the solvent , for example by evaporation. Usually, however, it is preferable to use a solution of the trimethylammonium or triethylammonium salt or mixtures thereof in a solvent directly for the preparation of the herbicidal composition of the invention, especially for the production of liquid herhicidal compositions without isolation of the bromoxyniltrimethylammonium or bromoxyniltriethylammonium salt. When bromoxynil is reacted with trimethylamine or triethylamine or a mixture thereof in a solvent to form bromoxyniltriethylammonium, bromoxyniltrimethylammonium salt or a mixture of these salts to form a salt directly usable for the production of a herbicidal composition, especially a liquid, water-miscible concentrate or wettable It is preferred to use a small excess of trimethylamine or triethylamine or mixtures thereof to obtain a solution of pH 8.5 to 9.5. If desired, additional auxiliaries, such as surfactants, may be incorporated into the solvent for the preparation of the bromoxyniltrimethylammonium or bromoxyniltriethylammonium salts or mixtures thereof.

When the herbicidal composition of the present invention comprises a bromoxyniltriethylammonium salt and water or a conventional organic solvent, it is preferred to use surfactants simultaneously.

The invention will be illustrated by the following examples.

Example 1

A water-miscible composition comprising a bromoxyniltriethylammonium salt can be obtained from the following mixture:

«70

Component

% W / v bromoxynil 34 triethylamine 15

Soprophor BSU (tristyrylphenol condensate with ethylene oxide containing 18 moles of ethylene oxide) 1,5 diethylene glycol 25 water up to 100 vol:%

This is done by mixing part of the water, diethylene glycol bromoxynil and triethylamine, with 15% triethylamine li being

2.6% by weight of triethylamine relative to the stoichiometric amount required to form the bromoxynil triethylainonium salt, the reaction is carried out with heating and stirring. Soprophor BSU is then added and the volume is made up to 100% by the addition of water. The resulting clear brown liquid o? The pH is perfectly miscible with water and can be diluted and used in a quantity of 0.5 liters per 100 to 300 liters of liquid to be sprayed per hectare. means? amount. 170 g of bromoxynil p. E. Per hectare to suppress the growth of dicotyledonous weeds. for example, Abutilon theophrasti, Amaranthus' retroflexus, Chenopodium album, Ipomea purpurea, Polygonum lapathifolium, Solanum nigrum and Xanthium strumarium after emergence in maize crop or? millet.

Similar water-miscible formulations containing the biocyloxyniltrimethylammonium salt are:. may be prepared as described above by:. triethylamine is replaced by an appropriate amount of trimethylamine and the composition thus obtained is used in a similar manner.

Example 2

An emulsifiable composition comprising a bromoxyniltriethylammonium salt can be obtained from the following mixture:

Weight /

S-bed / vol bromoxynil 34 triethylamine 12.4

Soprophor BSU 5.25

Arylan CA (70% solution in calcium dodecylbenzenesulfonate) 2,25 cyclohexanone 7,5% by volume

Solvesso 150 (aromatic

Cio diesel fractions up to 100% by volume

1Í2

This is done by mixing cyclohexa, non, boroxynil, and triethylamine with a portion of Solvesso 150. with heating and? stirring. Soprophor BSU is then added. and Ar.ylan CA and make up to 100% by adding Solvesso: 150. The resulting clear brown solution is directly emulsifiable in water and can be diluted with water and used in amounts.

1.5 liters of emulsifiable composition in 100 to 300 liters of liquid, to be sprayed on? hectare, which means. * an amount of 510 g of bromoxynil p.e. per hectare to suppress the growth of dicotyledonous weeds, for example, Abutilon theophrasti, Amaranthus retroflexus, Chenopodium album, Ipomea purpurea, Polygons lápathifoliumi, Solanum. nigrům? ai Xanthium! strumarium after emergence in maize 's or millet crops.

Similar · emulsifiable formulations containing! The bEOmoxyniltrimethylammonium salts can be prepared as described above. so that; triethylamine) is replaced by an appropriate amount of trimethylamine and the resulting composition is used in a similar manner.

Example 3

An emulsifiable composition comprising a bronioxyniltriethylammonium salt may be obtained from the following mixture:

Bromoxynil triethylamine component Soprophor BSU Arylan CA Solvesso 150 to

Weight / /%

12.4

5.25

2.25 100% vol.

The procedure is ¹ by mixing bromoxynil, triethylamine and part of Solvesso 150 with heating and stirring. Soprophor is then added. BSU 'and Arylan CA and make up to 100% by adding Solvesso 150. The resulting clear brown liquid is directly emulsifiable in water and can be diluted with water and used in an amount of 1.5 liters of emulsifiable agent in 100-300. liters of liquid to be sprayed per hectare, which is 510 g of bromoxynil pe per hectare to suppress the growth of dicotyledonous weeds such as Abutilon theophrasti, Amaranthus retroflexus, Chenopodium; album, Ipomea purpurea, Polygonum lapathifolium, Solanum nigrum and Xanthium. strumarium after emergence in maize stands; or millet.

TI

J

Example 4

A wettable powder containing bromoxyniltriethylammonium salt can be obtained from the following mixture:

Component Weight% bromoxynil 20 triethylamine 8.8

Soprophor BSU 2,5 diethylene glycol 10

Aerosil (silica in York very fine particles) up to 100

This is done by mixing bromoxynil, triethylamine (8.8% triethylamine represents a 2.5% excess weight of triethylamine as compared to the stoichiometric amount required to form the bromoxyniltriethylammonium salt), Soprophor BSU and diethylene glycol with heating and stirring until formation. of the clear solution at pH 9. Aerosil is then added with stirring and the mixture is stirred until the liquid is fully absorbed to give a powder which can be diluted with water and used at a rate of 0.75 kg of wettable powder in 100 to 300 liters of liquid intended for spraying per hectare, which means the use of 150 g of bromoxynil pe per hectare. The composition is used to suppress dicotyledonous weed growth, for example, Abutilon theophrasti, Amaranthus retroflexus, Chenopodium album, Ipomea purpurea, Polygons lapaihifolium, Solanum nigrum and Xanthium strumarium after emerging in corn or millet crops.

A similar wettable powder containing the bromoxyniltrimethylammonium salt can be obtained as described above by replacing triethylamine with an appropriate amount of trimethylamine and using the composition in a similar manner.

Example 5

Water dispersible granules containing. bromoxyniltriethylammonium salts can be obtained by thoroughly mixing a wettable powder containing the bromoxyniltriethylammonium salt obtained by the method of Example 4 with water up to 5% (v / v) to a solid paste, which is then granulated by extruder and the excess water is removed by drying to give water-dispersible granules which can be diluted with water and used at a rate of 5 kg of water-dispersible granules in 100 to 300 liters of sprayable liquid per hectare, equivalent to 1,000 g of bromoxynil per hectare to suppress dicotyledonous weed growth, for example, Abutilon theophrasti, Amaranthus retroflexus, Chenopodium album, Ipomea purpurea, Polygonum lapathiofolium, Solanum nigrum and Xanthium strumarium after emergence in! corn or millet crops.

Similar water dispersible granules containing the bromoxyniltrimethylammonium salt can be obtained by replacing triethylamine with an appropriate amount of trimethylamine.

Example 6

A water-miscible composition comprising bromoxyniltrimethylammonium salt can be obtained from the following mixture:

Weight /

Component / volume bromoxynil 34 trimethylamine 7.25

Soprophor BSU 1,5 tetrahydrofurfuryl alcohol 25 water to 100

This is done by mixing part of the water, tetrahydrofurfuryl alcohol and bromoxynil with stirring. Trimethylamine is then bubbled through the solution using a submerged tube until the pH of the solution changes to 8.0. Soprophor BSU is then added and the volume is made up to 100% by the addition of water. The resulting clear brown liquid is perfectly miscible with water and can be diluted with water and used in an amount of 1 liter of water miscible composition in 100 to 300 liters of spray liquid per hectare, which means using 340 g of bromoxynil pe per hectare to suppress growth dicotyledonous weeds such as Abutilon theophrasti, Amaranthus retroflexus, Chenopodium album, Ipomea purpurea, Polygons laphathifum, Solanum nigrum and Xanthium strumarium after emergence in maize or millet crops.

Example 7

An emulsifiable composition containing a bromoxyniltrimethylammonium salt can be obtained from the following mixture:

Weight /

Component / volume%

bromoxynil 34 trimethylamine 7.25 Soprophor BSU 3.75 Arylan CA 3.75 A mixture of cyclohexanone and the composition

Solvesso 150 in a volume ratio of 1: 1 to 100% by volume

This is done by mixing bromoxynil and part of a mixture of cyclohexanone and Solvesso 150 with heating and stirring. Trimethylamine is then bubbled through the solution

1 With submerged tube until all bromoxynil dissolves. Soprophor BSU and Arylan CA are then added and the volume is made up to 100% by the further addition of a mixture of cyclohexanone and Solvesso 150. The resulting clear brown liquid is directly emulsifiable in water and can be diluted with water to take 1 liter of emulsifiable per 100 to 300 liters of sprayable liquid per hectare, which means 340 liters per hectare of bromoxynil per hectare to inhibit the growth of Abutilon theophrasti, Amaranthus re-lexlexus, Chenopodium album, Ipomea purpurea, Polygonum lapathiofolium, Solanum nigrum and Xanthium strumarium.

Example 8

A water-miscible composition containing a bromoxyniltriethylammonium salt can be obtained from the following mixture:

Weight /

Component / volume% bromoxynil 34 triethylamine 15

Soprophor BSU (condensate of tristyrylphenol and ethylene oxide containing 18 moles of ethylene oxide) 1,5 tetrahydrofurfuryl alcohol 25 water up to 100% vol

This is done by mixing part of the water, tetrahydrofurfuryl alcohol, bromoxynil and triethylamine (15% by weight or by volume of triethylamine means 2.6% w / w excess triethylamine as compared to the amount required to form the bromoxyniltriethylammonium salt with stirring and heating. Soprophor BSU is added and the volume is made up to 100% by the addition of water The resulting clear brown pH 9 liquid is perfectly miscible with water and can be diluted with water and used in an amount of 0.5 liter of water miscible in 100 to 300 liters of liquid for spraying per hectare, which is 170 g of bromoxynil per hectare to inhibit the growth of dicotyledonous weeds such as Abutilon theophrasti, Amaranthus retroflexus, Chenopodium album, Ipomea purpurea, Polygonum lapathiofolium, Solanum nigrum and Xanthium strumarium corn or millet.

Example 9

An emulsifiable composition containing a bromoxyniltriethylammonium salt can be obtained from the following mixture:

Weight /

Component / volume% bromoxynil 34 triethylamine 12.4

Soprophor BSU 3.75

Aryan CA 3.75 mixture of cyclohexanone and composition

Solvesso 150 in a volume ratio of 1: 1 to 100% by volume

This is done by mixing part of a mixture of cyclohexanone and Solvesso 150, bromoxynil and triethylamine with heating and stirring. Soprophor BSU and Arylan CA are then added and the volume is made up to 100% by the addition of an additional portion of cyclohexanone / Solvesso 150. The resulting clear brown liquid is directly emulsifiable in water and can be diluted with water and applied at 1.5 liters of emulsifiable in 100 to 300 liters of liquid to be sprayed per hectare, which is 510 g of bromoxynil per hectare to suppress the growth of dicotyledonous weeds such as Abutilon theophrasti, Amaranthus retroflexus, Chenopodium album, Ipomea purpurea, Polygonum lapathifolium, Solanum nigrum and Xanthium pogrum emerging in corn or millet stands.

The progress which can be achieved by controlling the weeds with the composition according to the invention and the advantageous selectivity of bromoxyniltrimethylammonium and bromoxyniltriethylammonium salts in controlling dicotyledonous weeds after emergence in maize crops. millet compared to other widely used bromoxynil derivatives, for example bromoxynil octanoate, bromoxynil potassium salt and other bromoxynil salts with amines are described in the following experiments:

Experiment 1

The following devices were tested during this experiment:

A: A water-miscible product containing

34.0% p.e. (w / v)] bromoxyniltriethylammonium salt, prepared according to the method of Example 1.

B: Emulsifiable formulation

34.0% p.e. (w / v%) bromoxyniltriethylammonium salt, prepared according to the method of Example 3.

C: Emulsifiable% p.e. (w / v%) bromoxyniltriethylammonium salt, prepared according to the method of Example 2.

D: Water-miscible product containing

34.0% p.e. (w / v%) bromoxyniltrimethylammonium salt, prepared according to the method of Example 1.

E: An emulsified formulation containing 34.0 why. p.e. (w / v%) bromoxyniltrimethylammonium salt, prepared according to the method of Example 2.

F: Water miscible formulation containing 25% p.e. % (w / v) of potassium bromoxynil salt, 1.1% (w / v) of Soprophor BSU, 40% (w / v) tetrahydrofurfuryl alcohol and up to 100% (w / v) water prepared by the method of Example 1, except that the bromoxynil triethylammonium salt and diethylene glycol are replaced with an appropriate amount of the bromoxynil potassium salt and tetrahydrofurfuryl alcohol.

G: Commercial emulsified formulation containing 22.5% p.e. (w / v%) bromoxyniloctanoate, a total of 7.5% (w / v why) of Atlox 4,855 and Agrilan A, and up to 100% by volume of High Flash Naphtha CW (high boiling oil fraction) prepared according to Example 2 using Atlox 4,855 and Agrilan A are nonionic surfactants mixed with calcium dodecylbenzenesulfonate.

Maize (Zeam / mays), millet (Sorgbum bicolor) and wheat (Triticum aestivum) were grown in a greenhouse by sowing the seeds directly into 13 cm plastic pots containing John Innes # 1 soil, composition: 7 parts by volume of sterilized clay, 3 parts by volume of peat and 2 parts by volume of fine sand. The various weed species were grown from seed in a greenhouse and transferred to a 9 cm diameter plastic pot with the same filling as the crops at the seedlings stage. Three maize, millet, wheat or weed plants were grown in one pot. The average plant temperature was 15 ° C at night and 27 ° C by day with an average daytime of 16 hours. Three pots were used for each treatment, each with three plants of the same growth stage. Untreated pots with three plants were used as controls. When sprayed, the plants were in the following growth stage:

Crop Corn leaves 4 millet 3 Wheat wheat 3

Two-legged Weed Leaves

Amaranthus retroflexus (A.r.) 3

Polygonum lapathiiolium (P.l.j 3

Ipomea purpurea (I.p.J 3

Chenopodium album (C.a.J 4

Solanum nigrum (S.a.j 4

Xanthium strumarium (X.s. J 4

Abutilon theophrasti (A.T.) 3

The appropriate amount of the compositions A to G were diluted with ¹ 50 ml of water to spraying with a concentration of 85, 170, 340, 680 and 1360 g PE bromoxynil per hectare using a volume of 260 liters per hectare. Spraying is carried out with a laboratory scrubber at a pressure of 2000 kPa at a speed of 2.6 km / h. After spraying, the pots were returned to the greenhouse and the plants were watered from 24 hours after spraying daily.

days after spraying, an estimate of the percentage reduction in growth of each weed species compared to the untreated control groups was estimated. The growth suppression of each weed species was then calculated in% for each amount of composition used compared to the control plants. The results are shown in Table 1 below.

days after spraying, corn, millet and wheat damage was also estimated and whole plant necrosis was recorded in why. These results are shown in Table 2 below.

Composition Applied amount Controlled weed growth% All bromoxynil species g C.a. P.l. A.t. A.r. X.s. I.p. S.n. on average (p.e.) - ha?

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TABLE 2

Product Crop Necrotic leaf area in%

Application rate of bromoxynil g (p.e.) / Ha

170 340 680 1,360

AND maize (bromoxynil triethylammonium salt) (B) millet wheat maize (bromoxynil triethylammonium salt) C millet wheat maize (bromoxynil triethylammonium salt) D millet wheat maize (bromoxynil trimethylammonium salt E millet wheat maize (bromoxynil triethylammonium salt) F millet wheat maize (bromoxynil potassium salt) G millet wheat maize (bromoxynil octanoate) millet wheat (<means "less than")

The amount to be applied when using A to G to achieve 95% growth inhibition of all weed species was calculated by referring to the weed growth suppression ratio and the amount needed on log paper, taking into account the probability. The data and the amounts that can achieve 95% weed control are shown in Table 3, which shows that bromoxyniltrimethylammonium and bromoxyniltriethylammonium salts are 3 to 5.5 times more potent than bromoxynil potassium in controlling weed growth and compared to bromoxyniloctanoate, they are only 1.8 times less potent than the compound.

The amount of formulations A to G causing no more than 5% crop damage in the form of leaf necrosis when used in maize, millet and wheat stands was also calculated from the results shown in Table 2. The amount causing less than 5% crop damage is shown in following table 3.

From these data, the selectivity index of the amount applied, causing no more than 5% crop damage, was calculated

0 0 0 0 0 0 0 0 <5 6 0 0 0 0 0 0 0 0 0 <5 0 0 <5 5 18 0 0 0 0 0 0 0 0 0 5 0 0 0 <5 20 May 0 0 0 0 0 0 0 0 0 <5 0 0 <5 5 15 Dec 0 0 0 0 0 0 0 0 <5 10 0 0 0 5 15 Dec 0 0 0 0 <5 0 0 0 0 <5 0 0 0 <5 10 0 0 0 0 0 0 <5 8 17 60 0 5 7 23 42 0 0 0 <5 <5 Listed data are summarized in follow-

The selectivity indices clearly show that the bromoxyniltrimethylammonium and bromoxyniltriethylammonium salts are 2 to 5%.

5.5 times more selective than bromoxyniloctanoate when used against dicotyledonous weeds after emergence in maize stands; in addition, bromoxyniltrimethyl ammonium and bromoxyniltriethylammonium salt are 2.25 to 6.5 times more selective than bromoxyniloctanoate when used against dicotyledonous weeds in millet and bromoxyniltrime than. bromoxynil potassium salt in suppressing the emergence of dicotyledonous weeds after emergence and also more selective than bromoxynil potassium salt in suppressing the growth of dicotyledonous weeds after emergence in maize and millet crops. These selectivity indices show that bromoxyniltrimethyl ammonium and bromoxyniltriethylammonium salt are more selective in wheat stands, but unlike use in maize stands and millet selectivity in wheat stands is not preferable to the same values for bromoxynil octanoate when used against dicotyledonous weeds after emergence in wheat stands.

applied amount that provides 95% weed control

TABLE 3

Means

Selectivity index

Quantities causing not more than 5% of leaf necrosis of the bromoxynil crop (p. E.) / Ha

Quantities providing 95% weed control [bromoxynil

g (p. e.) / ha] maize millet wheat maize millet wheat AND (bromoxynil- triethylammonium salt) (B) 130 > 1360 1 020 > 1,360 > 10 7.8 > 10 (bromoxyniltriethylammonium salt) C 140 > 1,360 680 > 1,360 > 9.7 4.8 > 9.7 (bromoxynil- 190 1 360 680 > 1,360 7.1 3.6 > 7.1 triethylammonium salt) D (bromoxyniltri- 250 > 1360 680 > 1,360 > 5,4 2.7 > 5,4 methylammonium salt) E (bromoxyniltrl- methylammonium salt) F 235 900 680 > 1,360 3.8 2.9 > 5.8 (bromoxynil 720 > 1,360 1 020 > 1,360 > 1.9 1.4 > 1.9 potassium salt) G (bromoxynil- 140 250 170 1 360 1,8 1,2 9.7

octanoate) (> means "greater than")

Experiment 2

The following means were used in this experiment:

H: Water-miscible formulation containing 34.0% p.e. (W / v) bromoxyniltrimethylammonium salt, prepared by the method of Example 8.

I: Emulsifiable composition containing 34.0% p.e. (W / v%) bromoxyniltrimethylammonium salt, prepared by the method of Example 7.

J: A water miscible formulation containing 34.0% p.e. (W / v) bromoxyniltriethylammonium salt, prepared by the method of Example 78.

K: Emulsifiable composition containing 34.0% (w / v) bromoxyniltriethylammonium salt, prepared by the method of Example 9.

L: A water-miscible formulation containing 34.0% p.e. (w / v%) bromoxyniltriethanolammonium salt, prepared according to the method of Example 8 by replacing triethylamine with a stoichiometric amount of triethanolamine.

M: Emulsifiable composition containing 34.0% (w / v) of bromoxyniltrin-n-propylammonium salt, prepared according to the method of Example 9, except that triethylamine is replaced by a stoichiometric amount of tri-n-propylamine.

N: Emulsifiable formulation containing 34.0% p.e. (W / v) bromoxynil-butylammonium salt, prepared according to the method of Example 9, except that the triethylamine is replaced by a stoichiometric amount of tri-n-butylamine.

O: Emulsifiable composition containing 34.0% p.e. (w / v%) bromoxynilmethyl-di-n-octylammonium salt, prepared according to the method of Example 9, except that triethylamine was replaced by a stoichiometric amount of methyl-di-n-octylamine.

P: Water-miscible formulation containing 17.0% p.e. (W / v) of bromoxynil potassium salt, prepared as described in Example 8, except that bromoxynil and triethylamine are replaced with an appropriate amount of bromoxynil potassium salt.

Q: A water-miscible formulation containing 17.0% pe (w / v) of ammonium bromoxynil salt prepared by the method of Example 8 except that triethylamine is replaced with concentrated aqueous ammonia and used at a fair stoichiometric amount of bromoxynil and ammonia.

R: Emulsifiable formulation

34.0% (w / v) of bromoxyniloctanoate, prepared according to the method of Example 9, except that bromoxynil and triethylamine are replaced with the appropriate amount of bromoxyniloctanoate.

Maize, millet and dicotyledon weeds were grown in the greenhouse in the same manner as in Experiment 1. In the spraying, the plants were in the following growth stage:

Crop Leaves

Maize 3

Millet 3

Weeds

Ipomena purpurea (I. p

Abutilon theophrasti (A. t ·)

Amaranthus retroflexus (A. r.j

Chenopodium album (C. a.) Cotyledons + 1 right leaf cotyledons + 1 right leaf

The appropriate amounts of Formulations H-R were diluted in 50 ml of spraying water at a concentration of 85.170, 340, 680 and 1360 g p.e of bromoxynil per hectare, spraying at a volume of 260 liters per hectare. The treatment was carried out in the same manner as in Example 1, the control pots were not sprayed.

days after spraying, a visual estimate of the percentage reduction in growth for each weed species was made compared to untreated control plants. The average weed suppression of each weed species for each amount of active ingredient used and the total average weed suppression were then calculated as a percentage. The results are shown in Table 4 below.

days after spraying, a visual estimation of corn and millet damage was also made and growth necrosis was recorded as a percentage. The results are shown in Table 4 below.

days after spraying, a visual estimation of maize and millet damage was also made and growth necrosis in percent was recorded. The results are shown in Table 5 below.

TABLE 4

Means Amount used bromoxynil g (p. E.) / Ha Weed control in% Diameter all kinds I. p. A. t. A. r. C. a. H 85 50 10 10 10 20 May (bromoxyniltrime- 170 95 70 30 62 - 64 thylammonium salt] 340 100 ALIGN! 95. 90 95 95 680 100 ALIGN! 100 ALIGN! 100 ALIGN! 100 ALIGN! 100 ALIGN! 1 360 100 ALIGN! 100 ALIGN! 100 ALIGN! 100 ALIGN! 100 ALIGN! AND 85 75 35 30 35 42 (bromoxyniltrime- 170 100 ALIGN! 75 60 75 78 thylammonium salt] 340 100 ALIGN! 95 95 95 96 680 100 ALIGN! 100 ALIGN! 100 ALIGN! 100 ALIGN! 100 ALIGN! 1 360 100 ALIGN! 100 ALIGN! 100 ALIGN! 100 ALIGN! 100 ALIGN! J 85 85 30 40 35 47 (bromoxyniltriethyl- 170 100 ALIGN! 60 70 70 75 ammonium salt] 340 100 ALIGN! 95 100 ALIGN! 95 97 680 100 ALIGN! 100 ALIGN! 100 ALIGN! 100 ALIGN! 100 ALIGN! 1 360 100 ALIGN! 100 ALIGN! 100 ALIGN! 100 ALIGN! 100 ALIGN! TO 85 95 40 43 50 57 (br omoxyniltriethyl- 170 100 ALIGN! 70 80 100 ALIGN! 87 ammonium salt) 340 100 ALIGN! 100 ALIGN! 100 ALIGN! 100 ALIGN! 100 ALIGN! 680 100 ALIGN! 100 ALIGN! 100 ALIGN! 100 ALIGN! 100 ALIGN! L 85 60 20 May 10 20 May 27 Mar: (bromoxyniltriethyl- 170 90 40 40 75 61 ammonium salt) 340 100 ALIGN! 85 70 95 87 680 100 ALIGN! 100 ALIGN! 95 100 ALIGN! 99 1 360 100 ALIGN! 100 ALIGN! 100 ALIGN! 100 ALIGN! 100 ALIGN!

Means

Amount used bromoxynil g (p.e.j / ha)

Weed suppression in% Average

A. p. A. r. C. a. Of all species

M 85 60 0 0 0 15 Dec (bromoxyniltri-n- 170 95 10 20 May 60 46 -propylammonium 340 100 ALIGN! 35 65 80 70 salt) 680 100 ALIGN! 80 100 ALIGN! 100 ALIGN! 95 1 360 100 ALIGN! 100 ALIGN! 100 ALIGN! 100 ALIGN! 100 ALIGN! N 85 43 20 May 0 20 May 21 (bromoxyniltri-n- 170 100 ALIGN! 45 30 70 61 -butylammonium 340 100 ALIGN! 80 65 100 ALIGN! 86 salt) 680 100 ALIGN! 95 100 ALIGN! 100 ALIGN! 98 1360 100 ALIGN! 100 ALIGN! 100 ALIGN! 100 ALIGN! 100 ALIGN! 0 85 40 10 10 30 33 (omoxynilmethy br 1- 170 100 ALIGN! 30 30 70 57 -di-n-octylamo- 340 100 ALIGN! 60 50 100 ALIGN! 77 nium salt) 680 100 ALIGN! 98 100 ALIGN! 100 ALIGN! 99 1360 100 ALIGN! 100 ALIGN! 100 ALIGN! 100 ALIGN! 100 ALIGN! P 85 20 May 0 0 0 5 (bromoxynildrasel- 170 40 10 10 20 May 20 May salt) 340 100 ALIGN! 20 May 30 50 50 670 100 ALIGN! 50 60 90 75 1 360 100 ALIGN! 90 100 ALIGN! 100 ALIGN! 97 Q 85 40 0 0 0 10 (bromoxynil- 170 100 ALIGN! 0 20 May 40 40 ammonium salt) 340 100 ALIGN! 30 56 90 69 680 100 ALIGN! 70 90 100 ALIGN! 90 1360 100 ALIGN! 98 100 ALIGN! 100 ALIGN! 99 R 85 100 ALIGN! 53 40 60 63 (bromoxynil- 170 100 ALIGN! 80 95 90 91 octanoate) 340 100 ALIGN! 100 ALIGN! 100 ALIGN! 100 ALIGN! 100 ALIGN! 680 100 ALIGN! 100 ALIGN! 100 ALIGN! 100 ALIGN! 100 ALIGN! 1360 100 ALIGN! 100 ALIGN! 100 ALIGN! 100 ALIGN! 100 ALIGN! Means Crop TABLE 5 Necrotic leaf area in% Bromoxynil g (p. 85 170 340 680 e.) / ha 1360 H (bromoxyniltrimethyl- maize 0 0 0 0 5 ammonium salt) millet 0 0 0 0 5 I (bromoxyniltrimethyl- maize 0 0 0 0 5 ammonium salt) millet 0 0 0 <5 10 J (bromoxyniltriethyl- maize 0 0 0 0 0 ammonium salt) millet 0 0 0 0 5 K (bromoxyniltriethyl- maize 0 0 0 0 5 ammonium salt) millet 0 0 0 <5 10 L (bromoxyniltriethanol- maize 0 0 0 5 10 ammonium salt millet 0 0 <5 5 15 Dec M (bromoxynilpropylammonium maize) 0 0 0 5 15 Dec salt) millet 0 0 0 5 25 N (bromoxyniltrin-n-butyl- maize 0 0 <5 10 20 May ammonium salt) millet 0 0 <5 5 23 0 (broxyoxymethylen-di-n- maize 0 0 5 17 30 -octylammonium salt) millet 0 <5 5 20 May 35 P (broiroxynilotartrate) maize 0 0 0 0 0 salt) millet 0 0 0 0 5 Q (bromoxynilmonium) maize 0 0 O 0 0 salt) millet 0 0 0 0 0 R (bromoxyniloctanoate maize 0 0 8 19 Dec 40 millet 0 0 10 21 44

(<means "less than")

The amount of each of the compositions H to R required to 95% suppress the growth of all weeds was calculated as described in Experiment 1. The values obtained using 95% suppression of the growth of all weeds are given in Table 6 and clearly demonstrate that that bromoxyniltrimethylammonium and bromoxyniltriethylammonium salt are more effective than thromoxyniltriethanolammonium, bromoxyniltrin-n-propylammonium, bromoxyniltrin-n-butylammonium and bromoxynilmethyl-di-n-octylammonium salt,

3.5 to 4 times more potent than bromoxynil potassium, and 2 to 3 times more potent than bromoxynil ammonium in controlling the growth of dicotyledonous weeds after emergence. Bromoxyniltrimethylammonium and bromoxyniltriethylammonium salts have an activity close to the high activity of bromoxynil octanoate when used against dicotyledonous weeds after emergence, which is in particular higher than that of potassium and ammonium salts of bromoxynil; weed growth whereas the activity of bromoxynil ammonium salt and bromoxynil potassium salt is 5.5 to 4 times lower than that of bromoxynil octanoate.

The amount of formulations H to R used in the above experiments and causing a maximum of 5% crop damage, namely maize and millet in the form of leaf necrosis, was calculated from the results shown in Table 5, the values are also summarized in Table 6 below. the selectivity index for each crop was also calculated and these indexes are also shown in Table 6. It is clear from the selectivity indices that bromoxyniltrimethylammonium and bromoxyniltriethylammonium salts are highly selective in maize and millet, unlike bromoxyniltriethanolammonium, bromoxynil-tri-n- propylammonium, bromoxyniltrin-n-butylammonium, bromoxynilmethyl-di-n-octylammonium, ammonium and potassium salts of bromoxynil and bromoxinyl octanoate. The selectivity indices show that bromoxyniltrimethylammonium and bromoxyniltriethylammonium salts have 2.5 to more than 3.3 times higher selectivity than bromoxynil octanoate when used to suppress the growth of dicotyledonous weeds after emergence in maize stands; 1 x higher selectivity than bromoxyniloctanoate when used to suppress dicotyledonous weed growth after emergence in millet stands. The selectivity indices also show that the use of bromoxyniltriethanolammonium, bromoxyniltrin-n-propylammonium, bromoxyniltrin-n-butylammonium, bromoxynilmethyl-di-n-octylammonium or the ammonium or potassium salt of bromoxynil provides no advantage over the use of bromoxyniloctanoates in inhibiting biodelectivity after emergence in corn and millet stands.

'TABLE 6

Means

Quantity providing 95% weed control of Bromoxynil g (p.e.) / Ha

Amount causing no more than 5% damage (crop leaf necrosis) Bromoxynil g (p.e.) / Ha millet maize

Millet maize selectivity index

H (bromoxynil)

340 1,360 trimethylammonium salt]

I (bromoxynil trimethylammonium salt)

J (bromoxynil triethylammonium salt)

K (bromoxynil trimethylammonium salt)

L (bromoxynil triethanolammonium salt)

M i (bromoxynil tri-n-propylammonium salt)

N (bromoxynil tri-n-butylammonium salt)

O (bromoxynil methyl-di-n-octylammonium salt)

P (bromoxynil potassium salt)

Q (bromoxynil ammonium salt)

R (bromoxynil octanoate) (> means "greater than", <

290 1 360 320 > 1360 270 1360 450 680 520 680 400 560 600 340 1100 > 1360 800 > 1360 200 means "smaller." 300 than")

1 360 4.0 4.0 1200 4.7 4.1 1 360 > 4,3 4.3 1200 5.0 4.4 680 1.5 1.5 680 1.3 1.3 680 1.4 1.7 340 <1 <1 1360 > 1,2 1,2 1360 > 1.7 1.7 280 1.5 1.4

The following example illustrates a process for preparing bromoxyniltrimethylammonium and bromoxyniltriethylammonium salts.

Example 10

5.50 ml of triethylamine is added with stirring to a solution of 5.54 g of 3,5-dibromo-4-hydroxybenzonitrile in 40 ml of acetone. After 10 minutes, after the exothermic reaction has subsided, the reaction mixture is filtered and the filtrate is evaporated to dryness. A solid was obtained which was triturated with ethyl acetate and collected by filtration to give the bromoxynil triethylammonium salt, which may also be named triethylammonium-2,6-dibromo-4-cyanophenoxide. Yield: 5 g, cream-colored solid, m.p. 56-58 ° C.

Analysis: CnHieBrzNzO:

calculated:

C, 41.30; H, 4.76; N, 7.40.

ΤΆ Q1 07 ΡΤΊ f \ ·

H, 4.80; N, 7.30.

Following a similar procedure, but replacing triethylamine with trimethylamine and acetone ethanol, the bromoxyniltrimethylammonium salt is obtained, which may also be called trimethylammonium-2,6-dibromo-4-cyanophenoxide as a cream solid, m.p. 97-99 °. C. Analysis for C 10 H 12 Br 2 N 2 O calculated:

35.7% C, 3.6% H, 8.3% N, found:

C, 35.3; H, 3.4; N, 7.6.

3,5-dibromo-4-hydroxybenzonitrile (bromoxynil) can be obtained according to the method of Auwers and Reis, Ber., 29 (2), 2,355-2,360 (1896).

Claims (3)

P & EDM A herbicidal composition with increased selectivity in maize and millet crops based on 3,5-dibromo-4-hydroxybenzonitrile alkylamour salts, characterized in that it contains as active ingredient the trimethylammonium and / or triethylammonium salt of 3,5-dibromo-4-hydroxybenzonitrile and an acceptable diluent or surfactant, 2. A process for the preparation of an active ingredient according to claim 1, which comprises reacting a stoichiometric amount of 3,5-dibromo-4-hydroxybenzonitrile and trimethylamino or triethylamine in a suitable solvent, for example water, glycols, tetrahydrofurfuryl alcohol, acetophenone, cyclohexanone, isophorone, toluene, xylene, animal, vegetable or mineral oil, aliphatic alcohol or acetone. 3. A process according to claim 2, wherein the inert solvent is a liquid diluent suitable for incorporation into liquid herbicidal compositions. Severogratia, n. P., Plant 7, Most Price 2,40 Kčs