FI66621C - N N'-METHYLENBIS- (0,0-DIARYL-N-PHOSPHONMETHYLGLYCINNITRILER) DERASFRAMSTAELLNING HERBICIDIC COMPOSITION INNEHAOLLANDE D EMCH HERBICIDISK METHOD - Google Patents

Description

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J «a ® ^ 1) utläggningsskrift 66621 C Pr.tentti rίrt hy 12 11 1934 • JääS Prtsnt Eedcelat ^ ^ (51) K * Jk? /Ltt.a.3 C 07 F 9/40, A 01 N 57/22 FINLAND-FINLAND (21) 7732,96 (22) H «k» whyMyt — A — Blmlnfrftf 18.11.77 (23) ΑΜηρΙΜ — GIW || Mtadag 18.11.77 (41) TaMotHUmU - MvkoffwcRg 14.06.78

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Ptttenft · och rsflsterstyrsl—> '' AmMcm «h« 4 odt «djkittM paMcsnd 3 '' (32) (33) (31) swoMww Bsgfd prterk * 13.12.76, 20.06.77 USA (US) 750327, 807954 (71) Monsanto Company, 800 North LindberghBou1evard, St. Louis, Missouri 63166, USA (72) Gerard Anthony Dutra, Ladue, Missouri, USA (74) Oy Koister Ab (54) N, N'-methyl ibis- / 0,0-Diaryl-N-phosphonomethylglycine glycol /, their preparation, herbicidal combinations containing them and the herbicidal process - N, N'-methylenebis- / 0,0-diaryl-N-phosphonomethylglycine nitrile .7, deras framstä lining, herb ie id iskä compos it ioner innehll-lande dem och herbieidisk metod

The invention relates to novel N, N * -methylenebis- (O, O-diaryl-N-phosphonomethylglycine nitriles) which are useful as herbicides. In addition, this invention relates to herbicidal combinations and herbicidal methods using these bis-glycine nitriles.

In FI patent application no. 773495, the invention relates to certain mono- and diaryl esters of N-phosphonomethylglycine nitrile and their acid addition salts with strong acids. The present application relates to certain N, N'-methylene bis derivatives of these compounds. These derivatives are new organic chemical compounds and have been found to have particular use as post-emergence herbicides.

2,66621

The invention relates to N, N'-methylenebis-β, O-diaryl-N-phosphonomethylglycine nitriles of the formula Is 0 tl (RO) 2 -P-CH2-N - CH2 nc-ch2_2 wherein R is phenyl, which may be substituted by 1-2 halogen, lower alkyl, lower alkoxy and / or lower alkylthio substituents. The term "lower", as used herein, includes straight or branched chain alkyl groups having from 1 to 4 carbon atoms. Preferred alkyl groups are methyl and ethyl, and the preferred halogen is chlorine.

The N, N'-methylenebis compounds according to the invention can be prepared from or in parallel with the preparation of O, O-diaryl-N-phosphonomethylglycine nitriles in the above-mentioned FI patent application 773495. The co-preparation is carried out by forming a mixture consisting essentially of a phosphoric acid ester of the formula O (ro) 2-ph wherein R is as defined above and 1,3,5-tricyanomethyl-hexahydro-1,3,5-triazine (also called N -methylene glycine nitrile trimer) of the formula ch2cn C <SH2 3 66621

The mixture is heated to a temperature high enough to initiate and maintain the reaction of the phosphoric acid ester with the triazine to obtain the desired products.

Although a solvent is not necessary in the process of this invention, it is sometimes desirable to use a solvent for convenience and ease of reaction. The solvent is also useful in controlling the reaction temperature. The solvent used is one in which the triazine is soluble and which does not react with either reactant. Such inert solvents include acetonitrile, ethyl acetate, tetrahydrofuran, etc.

It has been found that the temperature can be as low as about 25 ° C and upwards to about 110 ° C. A higher temperature can be used, but no particular advantage is obtained because the reaction is essentially complete at a time when the temperature rises to about 85 ° C.

As can be seen from the above formulas of reactants, the molar ratio of phosphoric acid ester to triazine should be 3: 1. Higher or lower ratios can be used, but no corresponding advantage is obtained because higher ratios should separate the excess phosphoric acid ester and lower ester / triazine ratios allow by-product formation.

The reaction is usually carried out under normal pressure for economic reasons. However, higher or lower pressures can be used, although this is not found to provide any benefit.

The reaction is allowed to proceed until all phosphoric acid ester and triazine are consumed, as determined by nuclear magnetic resonance analysis. If such analysis shows the presence of impurities in the form of unreacted additional starting materials or solvent, the reaction mixture can be subjected to vacuum evaporation. The desired product is then isolated and purified by crystallization or chromatographic methods. During these latter steps, care should be taken to avoid hydrolysis of the ester moiety of the molecule.

4,66621 Using a sequential method, O, O-diaryl-N-phosphonomethylglycine nitrile is first prepared by the method disclosed in FI patent application 773495. This product is mixed with blocked phenylazomethine and heated in vacuo. This is believed to form an azo-adduct intermediate, after which heating is continued until the evolution of blocked aniline is complete. The reaction mixture is then recycled to isolate the desired methylene bis product.

Blocked phenylazomethins useful in the practice of this invention are those in which the phenyl ring contains substituents at each ortho position. These substituents may each be lower alkyl, except in the case of 2,6-di-t-butyl. In addition, a halogen or lower alkoxy substituent at the second ortho position may be used, the other having said lower alkyl. Other ring positions may also be substituted. Examples of blocked phenyl groups are 2-methyl-6-ethyl, 2,6-diethyl, 2-methyl-6-t-butyl, 2-chloro-6-t-butyl, 2-bromo-6-t-butyl, 2- methoxy-6-t-butyl, etc. In general, it has been found that without the inhibition defined above, the azomethine reactant trimerizes to hexahydrotriazine.

Glycine nitrile reactants prepared by the method described in FI patent application 773495 often contain phenolic impurities which may interfere with the preparation of the desired methylene bis compounds of this invention. Therefore, it is preferable to first prepare a salt of glycine nitrile with a strong acid, which salt precipitates and can be easily separated from the impurities. When the salt is neutralized, the desired glycine nitrile reactants are obtained. During neutralization, care should be taken that the aryl ester groups are not hydrolyzed.

The reaction of glycine nitrile and azomethine begins at room temperature, as observed by NMR analysis. Temperatures up to about 125 ° C can be used, although a temperature of about 60-80 ° C is preferred. As the reaction proceeds well under normal pressure, the blocked aniline formed can then react with the desired product to give the undesired adduct. Therefore, it is preferred to remove this blocked aniline once it is formed, and this is most effectively accomplished using conditions of reduced pressure, with the aniline distilling over during the reaction.

5,66621

The molar ratio of glycine nitrile to azomethine is preferably about 2: 1. Higher or lower ratios may be used, but these may reduce the yield by causing mixing with unreacted starting materials and the intermediate azo adduct. If desired, a basic catalyst can be used, although the reaction proceeds to the desired product even without a catalyst.

The following experiments are still intended to illustrate the invention; all parts are by weight unless otherwise indicated.

Example 1

A solution of di (3,4-dimethylphenyl) phosphite (8.7 g, 0.03 mol) in acetonitrile (10 ml) was added to 1,3,5-tricyanomethylhexahydro-1,3,5-triazine (2.04 g, 0.01 mol) in acetonitrile solution (50 ml) and the mixture was heated at 55 ° C for 90 hours. Filtration of the solid present and evaporation of the solvent gave a burgundy oil which, according to nuclear magnetic resonance analysis (nmr analysis), contained the desired product and the “amino” of this product Chromatography of the oil (8.0 g) on silica gel (450 g) 50% cyclo / 50% ethyl acetate (60 mL fractions) gave 0,0-di (3,4-dimethylphenyl) -N-phosphonomethylglycine nitrile in fractions 30 to 41. Fractions from 20-25 chromatography columns gave the solvent. after evaporation, 1.62 g of oil, ηβ = 1.5387, crystallization of this oil from carbon tetrachloride isooctane gave a white solid which was identified as N, N'-methylene-bis-Z'O-di (3,4- dimethylphenyl) -N-phosphonomethylglycine nitrile7, mp 79-80 ° C.

Example 2

A solution of di (m-tolyl) phosphite (10.7 g, 0.04 mol) in acetonitrile (100 ml) and 1,3,5-tricyanomethylhexahydro-1,3,5-triazine (2.72 g, 0.0133 moles) was heated at 50 ° C for three days. The solution turned burgundy in color and the solvent was evaporated to leave 12.4 g of a red oil (91.4% recovery), the oil (9.0 g) was chromatographed on silica gel eluting with a mixture of 60% cyclohexane and 40% ethyl acetate in 60 ml. verses. Fractions 45-63 were pure 0,0-di (m-tolyl) -N-phosphonomethylglycine nitrile. Fractions 28-40 from the chromatograph were evaporated in vacuo to give a solid, m.p. 113-114 ° C, which was identified as N, N'-methylenebis-ZO, O-di (m-tolyl) -N-phosphonomethylglycine nitrile to give L7. the following analysis result:

Calculated: C 62.50; H 5.69; N 8.32 Found: C 62.58; H 5.72; N 8.23.

Example 3

Di (p-methylthiophenyl) phosphite (30.4 g, 0.082 mol) and 1,3,5-tricyanomethyl-hexahydro-1,3,5-triazine (5.6 g, 0.0275 mol) were heated to 80 ° C: in one hour. The resulting dark red-brown oil was allowed to cool to room temperature and dissolved in carbon tetrachloride (200 mL). This solution was added to silica gel (30 g), stirred and filtered and then added again to silica gel (20 g) with stirring and filtration. Half of the resulting solution was taken up in silica gel (12.5 g) and chromatographed on silica gel (450 g) and eluted with a mixture of 60% cyclohexane and 40% ethyl acetate (60 ml fractions). Fractions 28-39 were combined to give 1.2 g of N, N'-methylenebis-E, O-di- 2 (E-methylthiophenyl) -N-phosphonomethylglycine nitrile, n-1 = 6151.

Example 4

Diphenylphosphite (234 g, 1.0 mol) was added to a solution of 1,3,5-tricyanomethyl-hexahydro-1,3,5-triazine (68 g, 0.333 mol) in acetonitrile (300 ml) and heated at 75-82 ° C for three hours. The solution was cooled and concentrated in vacuo to give a black oil which was predominantly glycine nitrile.

A sample of this oil (101 g) was taken up in silica gel (which was dissolved in chloroform, further silica gel was added and the solvent was evaporated) and this material was chromatographed on silica gel (1.1 kg) and eluted with chloroform (1 liter fractions). Fractions 13-14 were combined, concentrated and recrystallized from dichloromethane-cyclohexane to give 51 g of 0,0-diphenyl-N-phosphonomethylglycine nitrile.

Fractions 11-12 were combined, evaporated to an oil and the solid removed by filtration. The mother liquor from fractions 11-12 was chromatographed on silica gel (760 g) eluting with a mixture of 60% cyclohexane and 40% ethyl acetate (100 ml fractions). Fractions 40-49 were combined and recrystallized from cold carbon tetrachloride to give N, N'-methylenebis- / 0,0-diphenyl-N-phosphonomethylglycine nitrile7, m.p. 98-99 ° C. The product gave the following analytical result:

Calculated: C 60.39; H 4.90; N 9.09 Found: C 60.59; H 4.79; N 8.97.

Example 5

A mixture of 0,0-diphenyl-N-phosphonomethylglycine nitrile (78.05 g, 0.258 mol) and 2,6-diethylphenyl azomethine (21.06 g, 0.129 mol) was placed in a ball distillation apparatus with a catalytic amount (ca. 10 mg ) sodium methoxide. The mixture was heated at 65-75 ° C under vacuum (0.02-0.07 mm) for about one hour.

Distillation of 2,6-diethylaniline began almost immediately and continued for at least one hour. The vacuum was released and carbon tetrachloride (500 mL) was added until the oil crystallized. The hot solution was filtered and allowed to cool to room temperature. The solid was collected and washed with cold carbon tetrachloride, and the mother liquor was concentrated to give additional yields, which were combined to give a total of 72.5 g. The product was identified as N, N'-methylenebis-ZO, O-diphenyl-N-phosphonomethylglycine nitrile7, m.p. 100-100.5 ° C.

Example 6

A mixture of 0,0-di (E-methoxyphenyl) -N-phosphonomethylglycine nitrile (7.4 g, 0.01 mol) and 2,6-diethylphenyl azomethine (1.63 g, 0.01 mol) was prepared. resulting in a small exothermic reaction. After 0.5 h, the mixture was placed in a ball tube distillation apparatus and heated at 60-70 ° C under vacuum (0.1 mm) for about half an hour while distilling off 2,6-diethylaniline. The remaining product was cooled, stirred and dissolved in hot carbon tetrachloride. The solution was filtered, then ether was added to the remaining oil and decanted twice, chloroform was added to the oil, and then concentrated to give the product identified as N, N'-methylenebis-β), O-di (E-methoxyphenyl) -N-phospho-methylglycine nitrile7 red as leathery brown prisms, m.p. 90-92 ° C. This product gave the following analytical result: 8 66621

Calculated: C 57.07; H 5.20; N 7.61 Found: C 57.06; H 5.22; N 7.63.

Example 7

A mixture of 0,0-di (4-chloro-3-methylphenyl) -N-phosphinemethylglycine nitrile (2.8 g, 0.007 mol) and 2,6-diethylphenyl azomethine (0.57 g, 0.0035 mol) was prepared. ), resulting in a slight exothermic reaction. The mixture was placed in a ball distillation apparatus and heated at 75-80 ° C under vacuum (0.1 mm) for about half an hour while distilling off 2,6-diethylaniline. The residual oil was cooled and then crystallized from carbon tetrachloride / methylcyclohexane ether to give a white solid. The product was identified as N, N'-methylenebis-E, O-di (4-chloro-3-methylphenyl) -N-phosphonomethylglycine nitrile7, m.p. 89.5 -90.5 ° C. This product gave the following analysis result:

Calculated: C 51.87; H 4.23; N 6.91 Found: C 51.77; H 4.25; N 7.01.

Example 8 The herbicidal activity of various compounds of this invention after emergence is demonstrated as follows. The active ingredients are applied as a shower to 14-21 day old samples of different plant species. Spray, aqueous or organic solvent / aqueous solution containing the active ingredient and a surfactant (35 parts of the butylamine salt of dodecylbenzenesulfonic acid and 65 parts of pine oil condensed with ethylene oxide in a ratio of 11 moles of ethylene oxide and 1 mole of pine oil) , are applied to the plants in different pan sets with different amounts (kg / ha) of active ingredient. The treated plants are placed in a greenhouse, the effects are observed and recorded after about two weeks or about four weeks. The results obtained are given in Tables I and II.

The index of post-emergence herbicidal activity used in Tables I and II is as follows: 9,66621

Plant reaction Index 0-24% damage 0 25-49% damage 1 50-74% damage 2 75-99% damage 3

All dead 4

Species not present during treatment x These tables show WAT weeks after treatment and each treated plant species is represented by a code letter as follows: A - Canadian thistle K - Yarrow B - Burdock L - Soybean C - Velvet leaf M - Sugar beet D - Ipomoea species N - Wheat E - Wild flour whey 0 - Rice F - Persicaria hydropiper P - Millet G - Nutcracker Q - Wild buckwheat H - Duck grass R - Sesbania hemp I - Johnson grass S - Panicum Spp J - "Downy Brome" T - Creeping weed 1 ° 66621

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From the experimental results shown in Tables I and II, it can be seen that the post-emergence herbicidal activity of the compounds of this invention is for the most part general. However, in some special cases, some selectivity may be demonstrated. In this regard, it should be noted that each individual species selected for the above tests is a representative member of a known genus of plant species.

The herbicidal combinations of this invention, such as concentrates, which require dilution prior to application to plants, contain from 5 to 95 parts by weight of at least one active ingredient and from 5 to 95 parts by weight of the excipient in liquid or solid form, for example from about 0.25 to 25 parts by weight. a wetting agent, about 0.25 to 25 parts by weight of a dispersant and M · 5 to about 94.5 parts by weight of an inert, liquid extender, e.g. water, all parts being calculated on the weight of the total combination. If required, about 0.1 to 2.9 parts by weight of the inert liquid extender may be replaced with an anti-corrosion agent or an antifoam agent, or both. The combinations are prepared by mixing the active ingredient with an excipient such as diluents, extenders, carriers and conditioning agents to give combinations in the form of finely divided particulate solids, pellets, solutions, dispersions or emulsions. Thus, the active ingredient may be used with an excipient such as a finely divided solid, a liquid of organic origin, water, a wetting agent, a dispersing agent, an emulsifying agent, or some suitable combination thereof. Water is an inexpensive diluent for economy and comfort.

The herbicidal combinations of this invention, especially liquids and soluble powders, preferably contain one or more surfactants in sufficient amounts as a conditioning agent to make the given combination easily dispersible in water or oil. The combination of a surfactant with the combinations greatly increases their effectiveness. The term "surfactant" is understood to mean wetting agents, dispersing agents, suspending agents and emulsifying agents. Anionic, cationic and non-ionic substances can be used equally advantageously.

Preferred wetting agents are alkylbenzene and alkylnaphthalene sulfonates, sulfated fatty alcohols, amines or acid amides, sodium isothionate long chain acid esters, esters of sodium sulfosuccinates, sulfated or sulfonated fatty oil esters, sulfated or sulfonated fatty acid esters especially polyoxyethylene derivatives of isooctylphenol and nonylphenol) and polyoxyethylene derivatives of mono-higher fatty acid esters of hexitol anhydrides (e.g. sorbitan). Preferred dispersants include methylcellulose, polyvinyl alcohol, sodium lignin sulfonates, polymeric alkylnaphthalenesulfonates, sodium naphthalenesulfonate, polymethylene bisnaphthalenesulfonate, and sodium N-methyl-N- (long-chain acid).

Water-dispersible powder combinations containing one or more active ingredients, an inert, solid extender and one or more wetting and dispersing agents can be prepared. Inert, solid extenders are usually of mineral origin, such as natural clay, diatomaceous earth and synthetic minerals based on silicic acid, etc. Examples of such extenders are kaolinites, attapulgite clay and synthetic magnesium silicate. The water-dispersible powders of the present invention usually contain from about 5 to about 95 parts by weight of active ingredient, from about 0.25 to 25 parts by weight of wetting agent, from about

0.25 to 25 parts by weight of dispersant and 4.5 to about 94.5 parts by weight of an inert, solid extender, all parts being calculated on the weight of the total combination. If necessary, n.

Replace 0.1 to 2.0 parts by weight of a solid, inert extender with an anti-corrosion agent or an antifoam agent, or both.

Aqueous suspensions can be prepared by mixing and grinding an aqueous slurry of the water-soluble active ingredient in the presence of dispersants to give a concentrated slurry of very fine particles. The resulting concentrated aqueous suspension is characterized by an extremely small particle size, so that when diluted and sprayed the coverage is very uniform and usually contains from 5 to about 95 parts by weight of active ingredient, from about 0.25 to about 25 parts by weight of dispersant and from about 4 parts by weight. 5 to 94.5 parts by weight of water.

Emulsifiable oils are usually solutions of the active ingredient I * 66621 in water-immiscible or partially water-immiscible solvents together with a surfactant. Suitable solvents for the active ingredient of this invention include hydrocarbons and water-immiscible ethers, esters or ketones. Emulsifiable oil combinations generally contain about 5-95 parts of active ingredient, about 1-50 parts of surfactant and about 4-9 * + parts of solvent, all parts being calculated on the total weight of the emulsifiable oil.

Although the combinations of this invention may also contain other additives, e.g., fertilizers, herbicides and plant growth regulators, pesticides, etc., used as adjuvants or in combination with some of the adjuvants described above, it is preferred to use the combinations of this invention alone with sequential treatments with other herbicides, fertilizers, etc. reaching. For example, a field could be sprayed with a compound of this invention either before or after treatment with fertilizers, other herbicides, etc. The combinations of this invention can also be mixed with other substances, e.g., fertilizers, other herbicides, etc., and used as a single application. Useful chemicals in combination with the active ingredients of this invention, either simultaneously or sequentially, include, for example, triazines, ureas, carbamates, acetamides, acetanilides, uracils, acetic acids, phenols, thiol carbamates, triazoles, benzoic acids, nitriles, and the like.

Useful fertilizers together with the active ingredients are, for example, ammonium nitrate, urea, potash and super-phosphate.

In carrying out the present invention, effective amounts of glycine nitriles are applied to the plants or parts thereof in any suitable manner. The application of liquid or particulate solid combinations to plants or soil can be carried out by conventional methods, e.g. power sprayers, rod and hand sprayers and spray sprayers. The combinations can also be applied from aircraft as dust or mist due to their effectiveness in small doses.

The application of an effective amount of the combinations of this invention to a plant is essential and critical to the practice of this invention. The exact amount of active ingredient to be used depends on the desired effect on the plant as well as on factors other than the plant species and its stage of development, the amount of precipitation and also the specific compound used. In the press, in order to regulate Vegeta-dense growth, the active ingredients are applied in amounts of about 0.25 to about 25.0 kg / ha. An effective amount for phytotoxic or herbicidal control is the amount required for total or selective control, i.e., a phytotoxic or herbicidal amount. It is believed that one skilled in the art can readily determine the approximate application rate of the teachings in this specification, including examples.

Although the invention has been described in terms of specific modifications, their details should not be construed as limiting except to the scope indicated in the following claims.

Claims (10)

16 66621 A compound for use as a herbicide having the formula: O R (RO) 2-P-CH 2 -N - CH 2 nc-ch 2 (i) - J 2 wherein R is phenyl which may be substituted by 1-2 halogen, lower pialkyl, lower alkoxy and / or lower alkylthio substituent. Compound according to Claim 1, characterized in that R is phenyl, tolyl, methoxyphenyl, xylyl, chlorophenyl, methylthiophenyl or chlorotolyl. A herbicidal combination, characterized in that it contains a herbicidally effective amount of a compound of the formula: O (RO) 2-P-CH 2 -N - CH 2 NC-CH 2 (I) J 2 wherein R is phenyl which can be substituted with 1-2 halogen, lower alkyl, lower alkoxy and / or lower alkylthio substituents, and an inert diluent. Herbicidal combination according to Claim 3, characterized in that it contains a herbicidally effective amount of a compound of the formula (I) in which R is phenyl, tolyl, methoxyphenyl, xylyl, chlorophenyl, methylthiophenyl or chlorotolyl, and an inert diluent. 5. A herbicidal method, characterized in that the plant is contacted with a compound of the formula: 17 66621 ~ —I 0 II (RO) 2-P-CH2-N - CH2 nc-ch2 (i) 2 wherein R is phenyl / which may be substituted by 1-2 halogen, lower alkyl, lower alkoxy and / or lower alkylthio substituents by application of the compound about 0.25 to about 25 kg / ha for the plant site. Herbicidal process according to Claim 5, characterized in that the plant is contacted with a compound of formula (I) in which R is phenyl, tolyl, methoxyphenyl, xylyl, chlorophenyl, methylthiophenyl or chlorotolyl, by applying the compound from about 0.25 to about 25 kg / ha for the plant's habitat. A process for the preparation of a compound of formula: O II (RO) 2 -P-CH2-N --CH2 nc-ch2 (i) _] 2 wherein R is phenyl which may be substituted by 1-2 halogen, lower with an alkyl, lower alkoxy and / or lower alkylthio substituent, characterized in that a mixture of blocked phenylazomethine and a compound of the formula: O II (ro) 2-p-ch2-nh-ch2-cn in which R is as defined above, is formed, and heated in vacuo until the formation of blocked aniline ceases. Process according to Claim 7, characterized in that the blocked phenylazomethine has the formula: wherein X is lower alkyl and Y is lower alkyl, halogen or lower alkoxy, provided that X and Y do not both may be t-butyl. Process according to Claim 8, characterized in that a catalytic amount of base is added to the mixture. Process according to Claim 8, characterized in that X and Y are ethyl. 66621 1 9