Fatty acid derivatives for use as herbicides

Abstract

Fatty acid derivatives of the formula (I)

##STR00001##

wherein R.sup.1 is an aliphatic group containing 1 to 17 carbon atoms, which is linear, branched, saturated or unsaturated; R.sup.2, R.sup.3, R.sup.4, R.sup.5, R.sup.6, R.sup.7 are, independently, hydrogen, methyl, ethyl or hydroxymethyl; m, n and p are numbers from 0 to 17, with the proviso that m+n+p1, and m+n+p<18 where the different monomers can be arranged in statistical order, alternatingly or as a block copolymer and m, n and p can be a statistical mixture; X is, independently, a covalent bond or hydroxy methylene; R.sup.8 is an aliphatic group containing 1 to 10 carbon atoms, which is linear, branched, cyclic, saturated or unsaturated, substituted or unsubstituted phenyl or substituted or unsubstituted benzyl,
are useful as herbicides.

Claims

1. A method for controlling unwanted vegetation comprising the step of applying to the unwanted vegetation one or more fatty acid derivatives of the formula (I) ##STR00005## wherein R.sup.1 is an aliphatic group containing 1 to 17 carbon atoms, which is linear, branched, saturated or unsaturated; R.sup.2, R.sup.3, R.sup.4, R.sup.5, R.sup.6, R.sup.7 are, independently, hydrogen, methyl, ethyl or hydroxymethyl; m, n and p are numbers from 0 to 17, with the proviso that m+n+p1, and m+n+p<18 where the different monomers can be arranged in statistical order, alternatingly or as a block copolymer and m, n and p can be a statistical mixture; X is, independently, a covalent bond or hydroxy methylene; R.sup.8 is an aliphatic group containing 1 to 10 carbon atoms, which is linear, branched, cyclic, saturated or unsaturated, substituted or unsubstituted phenyl or substituted or unsubstituted benzyl.

2. The method according to claim 1, wherein R.sup.1 contains 5 to 15 carbon atoms.

3. The method according to claim 1, wherein R.sup.1 is n-octyl.

4. The method according to claim 1, wherein R.sup.8 is an alkyl group containing 1 to 10 carbon atoms.

5. The method according to claim 1, wherein R.sup.8 is methyl.

6. The method according to claim 1, wherein n is 0 and p is 0.

7. The method according to claim 6, wherein R.sup.2 is H and R.sup.3 is H.

8. The method according to claim 6, wherein m is a number from 1 to 10.

9. The method according to claim 6, wherein m is a number from 3 to 7.

10.-11. (canceled)

12. A herbicidal composition comprising one or more fatty acid derivatives of the formula (I) fatty acid derivative of the formula (I) ##STR00006## wherein R.sup.1 is an aliphatic group containing 1 to 17 carbon atoms, which is linear, branched, saturated or unsaturated; R.sup.2, R.sup.3, R.sup.4, R.sup.5, R.sup.6, R.sup.7 are, independently, hydrogen, methyl, ethyl or hydroxymethyl; m, n and p are numbers from 0 to 17, with the proviso that m+n+p1, and m+n+p<18 where the different monomers can be arranged in statistical order, alternatingly or as a block copolymer and m, n and p can be a statistical mixture; X is, independently, a covalent bond or hydroxy methylene; R.sup.8 is an aliphatic group containing 1 to 10 carbon atoms, which is linear, branched, cyclic, saturated or unsaturated, substituted or unsubstituted phenyl or substituted or unsubstituted benzyl, wherein the composition does not contain an organic solvent.

13. A fatty acid derivative of the formula (I) ##STR00007## wherein R.sup.1 is an alkyl group containing 5 to 13 carbon atoms, which is linear or branched R.sup.2, R.sup.3 are, independently, hydrogen, methyl, ethyl or hydroxymethyl with the proviso that one of R.sup.2 and R.sup.3 is hydrogen and the other is different from hydrogen; R.sup.4, R.sup.5 are hydrogen; m, n are independently numbers from 0 to 12, with the proviso that m+n>4, and m+n7 where the different monomers can be arranged in statistical order, alternatingly or as a block copolymer; p is 0 and R.sup.6 is a methyl group.

14. The fatty acid derivative according to claim 13, wherein R.sup.1 is n-octyl; R.sup.2 and R.sup.3 are H; R.sup.8 is methyl; m is a number <4 and >12, and n and p are 0.

15. A fatty acid derivative according to claim 13, wherein R.sup.1 is n-octyl; R.sup.2 and R.sup.3 are H; R.sup.8 is methyl; m is 6; and n and p are 0.

16. A fatty acid derivative according to claim 13, wherein R.sup.1 is an alkyl group containing 7 to 11 carbon atoms, which is linear or branched.

Description

EXAMPLES

[0156] The percentages stated hereinafter are percent by weight (% by weight), unless explicitly stated otherwise.

[0157] The raw materials used are:

TABLE-US-00001 Vorox Commercial pelargonic acid herbicide formulation, Compo Water deionized water or tap water MCPA MCPA auxin herbicide > 99% purity, Sigma aldrich Dicamba Dicamba auxin herbicide > 98% purity, Schirm Pelargonic Pelargonic acid > 99% purity, acid Novamont Genagen PA Nonanoy dimethyl amide solvent, Clariant Emulsogen Castor oil ethoxylate, Clariant EL 400 Hostaphat Phosphoric ester of alcohol 1306 ethoxylate, Clariant Aclonifen Aclonifen soil herbicide, Sigma Aldrich Abscisic acid Abscisic acid plant growth regulator, Sigma Aldrich Diflufenican Phenoxynicotinanilide soil herbicide, Sigma Aldrich Flufenacet Oxyacetamide soil herbicide, Sigma Aldrich Cloquintocet- Safener, Sigma Aldrich mexyl

Example 1: Preparation of the Fatty Acid Compounds of the Invention

[0158] The inventive compounds are listed in Table 1. All test substances were liquid, which makes them easy to handle and pourable.

TABLE-US-00002 TABLE 1 Test sub- stance Description R1 R2 R3 m R4 R5 n A1 Pelargonic acid 6 EO ester methyl ether linear C8-alkyl H H 6 0 A2 Pelargonic acid 8 EO ester methyl ether linear C8-alkyl H H 8 0 A3 Pelargonic acid 1 PO 6 EO ester methyl ether linear C8-alkyl H H 4 CH.sub.3 H 1 A4 Pelargonic acid 1 PO 2 EO ester methyl ether linear C8-alkyl 0 CH.sub.3 H 1 A5 C8/C10 fatty acid 4 EO ester methyl ether linear C7/C9-alkyl H H 4 0 A6 C8/C10 fatty acid 6 EO ester methyl ether linear C7/C9-alkyl H H 6 0 A7 C12/C14 fatty acid 3 EO ester methyl ether linear C11/C13-alkyl H H 3 0 A8 C12/C14 fatty acid 5 EO ester methyl ether linear C11/C13-alkyl H H 5 0 A9 Pelargonic acid 5 EO ester decyl ether linear C8-alkyl H H 5 0 A10 Pelargonic acid 3 EO ester hexyl ether linear C8-alkyl H H 3 0 A11 Dec-9-enoic acid 6 EO ester methyl ether linear C9 alkenyl H H 6 0 A12 Dodec-9-enoic acid 3 EO ester methyl ether linear C11 alkenyl H H 3 0 A13 3,5,5-trimethylhexanoic acid branched C9-alkyl H H 6 0 A14 Dodecanoic acid 6 EO ester methyl ether linear C11-alkyl H H 4 0 A15 Undecanoic acid 6 EO ester methyl ether linear C10-alkyl H H 6 0 A16 Pelargonic acid 6 EO ester ethyl ether linear C8-alkyl H H 6 0 A17* Pelargonic acid 6 EO diester A18* Pelargonic acid 8 EO diester Test Conversion rate sub- (according stance Description R6 R7 p X R.sup.8 to acid value) A1 Pelargonic acid 6 EO ester methyl ether 0 Me >85 A2 Pelargonic acid 8 EO ester methyl ether 0 Me >85 A3 Pelargonic acid 1 PO 6 EO ester methyl ether H H 2 Me >85 A4 Pelargonic acid 1 PO 2 EO ester methyl ether H H 2 Me >85 A5 C8/C10 fatty acid 4 EO ester methyl ether 0 Me >85 A6 C8/C10 fatty acid 6 EO ester methyl ether 0 Me >85 A7 C12/C14 fatty acid 3 EO ester methyl ether 0 Me >85 A8 C12/C14 fatty acid 5 EO ester methyl ether 0 Me >85 A9 Pelargonic acid 5 EO ester decyl ether 0 C10-alkyl >85 A10 Pelargonic acid 3 EO ester hexyl ether 0 C6-alkyl >85 A11 Dec-9-enoic acid 6 EO ester methyl ether 0 Me >85 A12 Dodec-9-enoic acid 3 EO ester methyl ether 0 Me >85 A13 3,5,5-trimethylhexanoic acid 0 Me >85 A14 Dodecanoic acid 6 EO ester methyl ether 0 Me >85 A15 Undecanoic acid 6 EO ester methyl ether 0 Me >85 A16 Pelargonic acid 6 EO ester ethyl ether 0 Et >85 A17* Pelargonic acid 6 EO diester >85 A18* Pelargonic acid 8 EO diester >85 *non-inventive examples

General Procedure for the Synthesis of Alcohol Ethoxylate Esters (A1-A16)

[0159] Alcohol ethoxylates were synthesized according to standard alkoxylation procedures as described in (e.g. US2012/310004). In a flask, equipped with a Dean-Stark-head, alcohol ethoxylates or glycerol were mixed with the respective carboxylic acid at a stoichiometric mixture, a catalytic amount of sulfuric acid was added and the mixture was heated up to 200 C. upon stirring under a constant stream of nitrogen. Reaction progress was followed by water separation and acid value. The final product was characterized by NMR spectroscopy and titration methods.

General Procedure for the Synthesis of Non-Inventive (Poly)Alcohol Fatty Acid Diesters (A17, A18)

[0160] In a flask, equipped with a Dean-Stark-head, a carboxylic acid alkoxylate and the respective carboxylic acid were mixed stoichiometric ratio of 1:1. A catalytic amount of sulfuric acid was added and the mixture was heated up to 200 C. upon stirring under a constant stream of nitrogen. The progress of the reaction was monitored by water separation and acid value titration. The final product was characterized by NMR spectroscopy and titration methods.

Example 2: Formulations with Pelargonic Acid 6 EO Ester Methyl Ether (A1)

[0161] The formulations have been prepared by mixing the different components listed in Table 2 to obtain homogeneous solutions.

TABLE-US-00003 TABLE 2 Formulations with PA derivatives (the percentages are % by weight) Formulation B1 B2 B3 B4 B5 B6 B7 B8 B9 B10 B11 B12 Test substance A1 81 44 97 99 99 90 50 70 95 99 85 90 Genagen PA 9 44 MCPA 3 1 Dicamba 1 Pelargonic acid 10 50 Aclonifen 30 Abscisic acid 5 Diflufenican 1 Flufenacet 15 Cloquintocet-mexyl 10 Emulsogen EL 400 10 8 Hostaphat 1306 4 Appearance clear, clear, clear, clear, clear, clear, clear, clear, clear, clear, clear, clear, stable stable stable stable stable stable stable stable stable stable stable stable

[0162] In all cases transparent liquid formulations were obtained which were stable over several weeks upon storage. In many cases e.g. B3-B12 the inventive compounds act as good solubilizers for active ingredients which facilitates the preparation of co-formulations with other active ingredients.

Example 3: Production of Spray Liquids

[0163] The inventive compounds were used to make spray liquids at relevant use concentration. These spray liquids are produced by mixing the various test substances in water, and the appearance and stability of the spray liquid were assessed after 24 h.

TABLE-US-00004 TABLE 3 Test Amount sub- [% stance Description by wt.] Appearance Stability Pelargonic acid 0.3 2 clear phases phase separation Pelargonic acid 5.0 2 clear phases phase separation Vorox 13.0 Cloudy stable homogeneous A1 Pelargonic acid 6 EO 0.3 Slightly cloudy stable ester methyl ether homogeneous emulsion A1 Pelargonic acid 6 EO 5.0 Clear solution stable ester methyl ether A2 Pelargonic acid 8 EO 0.3 Clear solution stable ester methyl ether A2 Pelargonic acid 8 EO 5.0 Clear solution stable ester methyl ether A5 C8/C10 fatty acid 4 0.3 Slightly cloudy stable EO ester methyl ether homogeneous emulsion A5 C8/C10 fatty acid 4 5.0 cloudy stable EO ester methyl ether homogeneous emulsion A6 C8/C10 fatty acid 6 0.3 Slightly cloudy stable EO ester methyl ether homogeneous emulsion A6 C8/C10 fatty acid 6 5.0 Clear solution stable EO ester methyl ether

[0164] The inventive compounds can be used as 100% substances without need for additional additives or formulation aids to obtain stable spray liquids. They are either water soluble and form clear homogeneous spray liquid or self-emulsifying in the spray liquid and form cloudy homogeneous emulsions that are stable over 24 h. By contrast, spray liquids comprising pelargonic acid at similar amount phase separate immediately. Stable spray liquids can only be achieved with pelargonic acid when they are formulated with appropriate emulsifiers and other formulation aids like in the commercial benchmark Vorox. Consequently the formulated products always comprise an active substance content of pelargonic acid much lower than 100% (e.g. Vorox exhibits 25% pelargonic acid content).

Example 3: Results of Greenhouse Trials to Test Herbicidal Activity

[0165] Standard post emergence herbicide application procedures were used, as described below, to apply inventive compounds and formulations listed in the tables 1 and 2, as well as the reference materials.

[0166] Seed of monocotyledonous and dicotyledonous harmful plants such as Abutilon theophrasti (ABUTH), Alopecurus myosuroides (ALOMY), Amaranthus retroflexus (AMARE), Digitaria Sanguinalis (DIGSA), Erigeron canadensis (ERICA), Lolium perenne (LOLPE), Solanun nigrum (SOLNI), Viola arvensis (VIOAR) were sowed in 18 cm.sup.2 pots. The plants were placed in a greenhouse under controlled environmental conditions, and sub-irrigation. About one week after emergence, seedlings were thinned as needed, including removal of any unhealthy or abnormal plants, to create a uniform series of test pots.

[0167] The plants were maintained for the duration of the test in the greenhouse, where they received a mean of 70 mol m.sup.2 s.sup.1 of light per day/night. Temperatures averages about 24 C. during the day and about 20 C. during the night. Plants were sub-irrigated throughout the test to ensure adequate soil moisture levels.

[0168] Pots were assigned to different treatment in a randomized experimental design. A set of pots was left untreated as a reference against which effects of the treatments could later be evaluated. Applications of tested formulations were made in a spray cabin model SPK B CT02 designed by CheckTec using the following parameters: [0169] nozzle Lechler LU-120-08, 1000 L/ha, 3 bars, 0.56 m/s [0170] nozzle Lechler LU-120-06, 500 L/ha, 3 bars, 0.7 m/s.

[0171] The distance of the nozzle from the plants was between 50 to 53 cms.

[0172] After treatment, pots were returned to the greenhouse until ready for evaluation (6 hours after treatment (6HAT), 1 day after treatment (1DAT), and 2 days after treatment (2DAT).

[0173] For evaluation of herbicidal effectiveness, all plants in the test were examined by a single technician, who recorded percent control, a visual measurement of the effectiveness of each treatment by comparison with untreated plants. Control of 0% indicates no effect, and control of 100% indicates that all of the plants are completely dead. The reported % control values represent the average for all replicates of each treatment.

TABLE-US-00005 Description of effectiveness against weeds Descriptor Control Substance Highly effective 70-100% A1, A4, B1-B6 Effective 50-69.9% A2, A3, A5-A10, A13, A14 Moderately effective 20-49.9% A11, A12, A15 Not effective 0-19.9% A17, A18

[0174] Test substances according to the invention such as, for example, the compounds A1, A2, A3, A4, A5, A6, A7, A8, A9, A10, A11, A12, A13, A14, A15, A16 and the formulations B1, B2, B3, B4, B5, B6 from the above tables 1 to 2 and, as benchmarks, pelargonic acid as well as the commercial formulation Vorox, show a herbicidal activity from moderately effective to highly effective against a plurality of the harmful plants at an application rate of 5-20% w/v of applied substances per hectare in a spray volume of 500-1000 liters per hectare when applied by broadcast foliar method, in particular against one, two, three, four, five, six, seven, or even all of the harmful plants selected from the group consisting of ABUTH, ALOMY, AMARE, ERICA, DIGSA, LOLPE, SOLNI and VIOAR.

[0175] Further test substances according to the invention such as, for example, the compound A1 and A4 and the formulations B1, B2, B3, B4, B5, B6 from the above tables 1 to 2 and also the commercial formulation Vorox, show a highly effective herbicidal activity against several, in particular three or more, of the mentioned harmful plants when applied by broadcast foliar method at an application rate of 5-20% w/v of applied substances per hectare in a spray volume of 500-1000 liters per hectare when applied by broadcast foliar method.

[0176] Generally, the compounds according to the invention displayed particularly similar or better herbicidal activity than the standard products in post-emergence application method against several harmful plants selected from the group, ALOMY, AMARE, DIGSA, SOLNI and VIOAR.

Example 4: Volatility Measurements

[0177] The volatility of the test substances from the spray deposit was measured time dependent. All measurements have been carried out using a concentration of 50 g/L of the test substances in the application solution. The reference pelargonic acid was used at a concentration of 30 g/L and the commercial benchmark Vorox was applied at a concentration of 130 g/L. The pH drop volumes of 10 l of the spray liquids which amounts to 500 g of test substance were then applied on two different substrates. An inert wettable synthetic substrates and non-permeable leaf cuticles were used as substrates. There were 3-5 repetitions per substrate, treatment and time, respectively. After evaporation of drop water, the substrates were weighed to obtain the initial weight and placed under a sealed box with defined air suction output volume of 30 m.sup.3/h. The volatility has been determined after the desired measurement time of 4 h, 24 h and 48 h by weighing of the substrates to obtain the remaining weight of the test substances. The fraction of remaining test substance in % is obtained by the ratio of remaining test substance compared to the initial weight of test substance. The volatilized amount was calculated by subtraction of the remaining test substance of the initial applied amount. The volatilized fraction of test substance in % is obtained by the ratio of volatilized test substance compared to the initial weight of test substance. A substrate without test substance is used as reference to account for changes in environmental conditions such as humidity. Concentrations used are based on ca. 3% pelargonic acid equivalent

TABLE-US-00006 TABLE 4 Volatilized fraction measured on non-permeable leaf cuticles Vol- Vol- Vol- Test atilized atilized atilized sub- fraction fraction fraction stance pH 4 h 24 h 48 h Pelargonic acid 4 55.7 78.9 80.6 Pelargonic acid 7 29.2 33.8 35.3 Vorox 4 21.8 46.0 49.9 Vorox 7 13.0 29.4 33.9 A1 Pelargonic acid 6 EO ester 4 1.5 4.8 5.2 methyl ether A2 Pelargonic acid 8 EO ester 4 1.7 2.1 2.8 methyl ether A9 Pelargonic acid 5 EO ester 4 8.6 11.7 22.8 decyl ether A10 Pelargonic acid 3 EO ester 4 6.2 14.7 18.9 hexyl ether A17 Pelargonic acid 6 EO diester 4 0.6 1.5 0.6 A18 Pelargonic acid 8 EO diester 4 0.6 1.7 4.0

TABLE-US-00007 TABLE 5 Volatilized fraction measured on inert wettable synthetic substrates Vola- Vola- Vola- Test tilized tilized tilized sub- fraction fraction fraction stance pH 4 h 24 h 48 h Pelargonic acid 4 3.9 19.1 35.2 Pelargonic acid 7 7.3 21.3 27.9 Vorox 4 3.9 13.6 22.7 Vorox 7 1.7 7.1 12.0 A1 Pelargonic acid 6 EO 4 0.2 0.6 1.2 ester methyl ether A2 Pelargonic acid 8 EO 4 0.3 0.2 0.4 ester methyl ether A9 Pelargonic acid 5 EO 4 0.3 1.2 1.9 ester decyl ether A10 Pelargonic acid 3 EO 4 0.9 4.4 7.2 ester hexyl ether A17 Pelargonic acid 4 0.6 1.0 1.3 6 EO diester A18 Pelargonic acid 4 0.5 0.7 0.9 8 EO diester

[0178] The volatility of the inventive compounds is drastically reduced for both measured substrates compared to the pelargonic acid and the commercial benchmark product Vorox, even when compared to data at neutral pH.

[0179] The lower volatility of the inventive compounds also results in a reduced smell compared to pelargonic acid and the commercial benchmark product Vorox.

Example 5: Results for Test Plant Growth Regulator Activity for Blossom Thinning in Orchards

[0180] Fruit trees were sprayed with substance A1 (Pelargonic acid 6 EO ester methyl ether), several days before the expected full blossoming in the greenhouse, and also in a field trial to test the blossom thinning, which is used to increase the fruit production. Different fruit trees and varieties were chosen for each trial to demonstrate that the method of the present invention is applicable to a wide range of fruits trees and varieties such as Fuji, Tsugaru, Starking Delicious, Jona Gold, Mutsu, Ourin, Kougyoku, Asahi, Senshu, Red Delicious, Golden Delicious, Granny Smith, Jonathan Rome Beauty, Yellow Newton, Baldwin, Cortland, Grimes and McIntosh apple trees.

[0181] Plots (3 trees per plot in field trials; 1 tree per plot in greenhouse) were assigned to different treatments in a randomized experimental design. One plot was left untreated as a reference against which effects of the treatments could later be evaluated.

[0182] The test substance A1 was diluted in water in a range of 1-10% and the spray solution was sprayed in an amount of about 2 to about 15 liters per apple tree (height: about 2-2.5 m, width: about 1-1.5 m). The Application was made with a high-pressure power backpack sprayer manufactured by SOLO Kleinmotoren GmbH.

[0183] The treated trees were evaluated regarding flower thinning effect, but also regarding undesired effects by chemical injury such as leaf browning, leaf malformation, etc.

[0184] Test substance A1 showed excellent results as flower thinning agent by leading to removal of flowers or interrupting the reproductive part of the flowers without significantly harming the tree, avoiding major injuries to leaves and branches when evaluated after treatment.