Patent Application
20140094370
This invention relates to the use of aromatic esters as adjuvants in compositions, particularly for agrochemical use, as well to compositions comprising such an aromatic ester, in combination with at least one agrochemical. The invention further extends to methods of making and using such compositions. In particular the present invention relates to such compositions when formulated as, or comprised by, an emulsion concentrate (EC), an emulsion in water (EW), a suspension of particles in water (SC), a microcapsule formulation (CS), a suspension of particles with an emulsion (SE), a dispersion concentrate (DC) or an oil suspension (OD).
The efficacy of the active ingredients (AIs) in an agrochemical composition can often be improved by the addition of further ingredients. The observed efficacy of the combination of ingredients can sometimes be significantly higher than that which would be expected from the individual ingredients used (synergism). An adjuvant is a substance which can increase the biological activity of and AI but is itself not significantly biologically active. The adjuvant is often a surfactant, and can be included in the formulation or added separately, e.g. by being built into emulsion concentrate formulations, or as tank mix additives.
In addition to the effect on biological activity, the physical properties of an adjuvant are of key importance and must be selected with a view to compatibility with the formulation concerned. For instance, it is generally simpler to incorporate a solid adjuvant into a solid formulation such as a water-soluble or water-dispersible granule. In general adjuvants rely on surfactant properties for biological activity enhancement and one typical class of adjuvants involves an alkyl or aryl group to provide a lipophilic moiety and a (poly)ethoxy chain to provide a hydrophilic moiety. Much has been published on the selection of adjuvants for various purposes, such as Hess, F. D. and Foy, C. L., Weed technology 2000, 14, 807-813.
The present invention is based on the discovery that aromatic esters with relatively long hydrocarbon chains are surprisingly effective adjuvants, significantly enhancing the biological activity of active ingredients. Aromatic esters of varied hydrocarbon chain lengths have until now only been known as solvents (such as Benzoflex 181™ and Finsolv TN™), emollients, plasticisers, and thickening agents, for use in various industries. There is also a meagre amount of information presently available on preferentially shorter chain aromatic esters having putative adjuvant properties in the context of agrochemical compositions. However, according to the surprising effects underpinning the present invention, this formulation dogma will be swept aside, at least to some extent, by the revelation that it is in fact longer chain aromatic esters (in particular phthalate derivatives) which possess the greater adjuvant properties.
The present invention accordingly provides the use of an aromatic ester of formula (I)
wherein
for enhancing the biological activity of an agrochemical active ingredient.
In a second aspect the invention provides for the use of an aromatic ester of formula (I) as described herein as an adjuvant in an agrochemical composition.
In a third aspect the invention provides for the use of an agrochemical composition as described herein to control pests.
In a further aspect there is provided a method of controlling a pest, comprising applying a composition of the invention to said pest or to the locus of said pest.
In yet a further aspect there is provided a method of making an agrochemical composition as described herein, comprising combining an active ingredient, a surfactant and an aromatic ester of formula (I).
In a yet further aspect the invention provides for the use of an aromatic ester of formula (I) as described herein as an adjuvant /synergist for an agrochemical.
Alkyl groups and moieties are straight or branched chains, and unless explicitly stated to the contrary, are unsubstituted. Examples of suitable alkyl groups for use in the invention are hexyl, heptyl, octyl, nonyl, decyl, undecyl, dodecyl, tridecyl, tetradecyl, pentadecyl, hexadecyl, heptadecyl, octadecyl, nonadecyl and eicosyl groups.
Alkenyl groups and moieties are straight or branched chains having a single carbon-carbon double bond, and unless explicitly stated to the contrary, are unsubstituted. Examples of suitable alkenyl groups for use in the invention are hex-1-enyl, hex-2-enyl, hex-3-enyl, hept-1-enyl, oct-1-enyl, non-1-enyl, dec-1-enyl, undec-1-enyl, and groups derived from monoenoic fatty acids including cis-4-decenyl, cis-9-decenyl, cis-5-laurolyl, cis-4-dodecenyl, cis-9-tetradecenyl, cis-5-tetradecenyl, cis-4-tetradecenyl, cis-9-hexadecenyl, cis-6-hexadecenyl, cis-6-octadecenyl, cis-9-octadecenyl, trans-9-octadecenyl, cis-11-octadecenyl, cis-9-eicosenyl, cis-11-eicosenyl, cis-11-docosenyl, cis-13-docosenyl and cis-15-tetracosenyl.
Alkyldienyl groups and moieties are straight or branched chains having two carbon-carbon double bond, and unless explicitly stated to the contrary, are unsubstituted. Examples of suitable alkyldienyl groups for use in the invention are buta-1,3-dienyl, penta-1,3-dienyl, penta-2,4-dienyl, penta-1,4-dienyl, hex-1,3-dienyl, hept-1,3-dienyl, linoleyl, and linoelaidyl.
Alkyltrienyl groups and moieties are straight or branched chains having three carbon-carbon double bond, and unless explicitly stated to the contrary, are unsubstituted. Examples of suitable alkyldienyl groups for use in the invention hex-1,3,5-trienyl, hepta-1,3,5-trienyl, and linolenyl.
In particularly preferred embodiments of the invention, the preferred values for n, as well as the preferred groups for R1 & R2, in any combination thereof (unless specifically stated otherwise) are as set out below.
As described herein, compounds of formula (I) may be benzoic acid esters or esters of phthalic acid, isophthalic acid or terephthalic acid. Phthalic acid esters are preferred. Preferably, each R2 is independently a C4-C20 alkyl group. More preferably each R2 is independently a C6-C20 alkyl group, more preferably a C6-C13 alkyl group and may be for example n-hexyl, isoheptyl, 2-ethylhexyl, isononyl, isodecyl, isoundecyl, isododecyl, or isotridecyl. Most preferably each R2 is a C6-C10 alkyl group.
In certain embodiments each R2 is independently a C6, C8 or C10 alkyl group. In further embodiments each R2 is independently n-hexyl, 2-ethylhexyl, or isodecyl.
As described herein n may be an integer of 1 or 2 preferably 2. In particularly preferred embodiments when n is 2, each R2 is the same.
Examples of compounds of formula (I), which may be used in the invention and which are available commercially include for example, those described in Table 1 below.
Alternatively, compounds of formula 1 may be synthesised according to the general principals outlined below.
Where n has a value of 1, compounds of formula (I) are benzoic acid esters and may be synthesised using well-known methodology as described for example in reaction schemes 1 and 2 below.
An alcohol of formula (A) is reacted with an acid chloride of formula (AC) in order to form a benzoic acid ester of formula (I), wherein R2 is an appropriate alkyl group as defined hereinbefore.
An alcohol of formula (A) is reacted with an acid anhydride of formula (AA) to form a benzoic acid ester of formula (I) plus an acid of formula (AC), in which R2 is a suitable alkyl group as defined hereinbefore. In an analogous way, phthalate esters for use in the invention may be produced by esterification of phthalic anhydride with an alcohol of formula (A).
Alcohols of formula (A), acid chlorides of formula (AC) and acid anhydrides of formula (AA) are readily available or may be synthesised using standard methodology well known in the art.
As stated previously, the present invention is based on the unexpected finding that compounds of formula (I) are particularly good adjuvants in agrochemical formulations. In particular, compounds of formula (I) display the surprising property of enhancing the biological activity of an agrochemical active ingredient in an agrochemical composition. As used herein, “enhancing the biological activity” means increasing the potency of an agrochemical active ingredient, and/or decreasing the application rate required to achieve control of the target organism. Accordingly, such adjuvants may be combined with an active ingredient, which is an agrochemical, in order to form an agrochemical composition. The present invention extends to a method of making such an agrochemical composition, wherein said method comprises combining a compound of formula (I) with an agrochemically active ingredient, and optionally a surfactant. The noun “agrochemical” and term “agrochemically active ingredient” are used herein interchangeably, and they include herbicides, insecticides, nematicides, molluscicides, funcgicides, plant growth regulators, and safeners. Suitable herbicides include bicyclopyrone, mesotrione, fomesafen, tralkoxydim, napropamide, amitraz, propanil, pyrimethanil, dicloran, tecnazene, toclofos methyl, flamprop M, 2,4-D, MCPA, mecoprop, clodinafop-propargyl, cyhalofop-butyl, diclofop methyl, haloxyfop, quizalofop-P, indol-3-ylacetic acid, 1-naphthylacetic acid, isoxaben, tebutam, chiorthal dimethyl, benomyl, benfuresate, dicamba, dichlobenil, benazolin, triazoxide, fluazuron, teflubenzuron, phenmedipham, acetochlor, alachlor, metolachlor, pretilachlor, thenylchlor, alloxydim, butroxydim, clethodim, cyclodim, sethoxydim, tepraloxydim, pendimethalin, dinoterb, bifenox, oxyfluorfen, acifluorfen, fluoroglycofen-ethyl, bromoxynil, ioxynil, imazamethabenz-methyl, imazapyr, imazaquin, imazethapyr, imazapic, imazamox, flumioxazin, flumiclorac-pentyl, picloram, amodosulfuron, chlorsulfuron, nicosulfuron, rimsulfuron, triasulfuron, triallate, pebulate, prosulfocarb, molinate, atrazine, simazine, cyanazine, ametryn, prometryn, terbuthylazine, terbutryn, sulcotrione, isoproturon, linuron, fenuron, chlorotoluron and metoxuron.
Suitable fungicides include isopyrazam, mandipropamid, azoxystrobin, trifloxystrobin, kresoxim methyl, famoxadone, metominostrobin and picoxystrobin, cyprodanil, carbendazim, thiabendazole, dimethomorph, vinclozolin, iprodione, dithiocarbamate, imazalil, prochloraz, fluquinconazole, epoxiconazole, flutriafol, azaconazole, bitertanol, bromuconazole, cyproconazole, difenoconazole, hexaconazole, paclobutrazole, propiconazole, tebuconazole, triadimefon, trtiticonazole, fenpropimorph, tridemorph, fenpropidin, mancozeb, metiram, chlorothalonil, thiram, ziram, captafol, captan, folpet, fluazinam, flutolanil, carboxin, metalaxyl, bupirimate, ethirimol, dimoxystrobin, fluoxastrobin, orysastrobin, metominostrobin and prothioconazole.
Suitable insecticides include thiamethoxam, imidacloprid, acetamiprid, clothianidin, dinotefuran, nitenpyram, fipronil, abamectin, emamectin, bendiocarb, carbaryl, fenoxycarb, isoprocarb, pirimicarb, propoxur, xylylcarb, asulam, chlorpropham, endosulfan, heptachlor, tebufenozide, bensultap, diethofencarb, pirimiphos methyl, aldicarb, methomyl, cyprmethrin, bioallethrin, deltamethrin, lambda cyhalothrin, cyhalothrin, cyfluthrin, fenvalerate, imiprothrin, permethrin and halfenprox.
Suitable plant growth regulators include paclobutrazole and 1-methylcyclopropene.
Suitable safeners include benoxacor, cloquintocet-mexyl, cyometrinil, dichlormid, fenchlorazole-ethyl, fenclorim, flurazole, fluxofenim, mefenpyr-diethyl, MG-191, naphthalic anhydride, and oxabetrinil.
Of course, the various editions of The Pesticide Manual [especially the 14th and 15th editions] also disclose details of agrochemicals, any one of which may suitably be used with the present invention.
The skilled man will appreciate that compositions of the invention may comprise one or more of the agrochemicals as described above.
Compositions of the invention will typically comprise the agrochemical in an amount that is recommended in the art. Generally the agrochemical will be present at a concentration of about 0.001% to 90% w/w. The skilled man will appreciate that compositions of the invention may be in the form of a ready-to-use formulation or in concentrate form suitable for further dilution by the end user, and the concentration of agrochemical and compound of formula (I) will be adjusted accordingly. In concentrated form, compositions of the invention typically comprise agrochemical at 5 to 75% w/w, more preferably 10 to 50% w/w agrochemical. Ready-to-use compositions of the invention will typically comprise from 0.0001% to 1% w/w, more preferably from 0.001% to 0.5% w/w, and more preferably still from 0.001% to 0.1% w/w agrochemical.
Typically a compound of formula (I) will comprise from about 0.0005% to about 90% w/w of the total composition. When in concentrated form, compositions of the invention typically comprise a compound of formula (I) from 1% to 80% w/w, preferably from 5% to 60% w/w and more preferably from 10% w/w to 40% w/w. Ready to use compositions of the invention typically comprise a compound of formula (I) from about 0.05% to about 1% w/w of the total composition, more preferably still from about 0.1% to about 0.5% w/w of the total composition. In specific embodiments the aromatic ester will be included at concentrations of 0.1%, 0.2%, 0.25%, 0.3%, 0.4% or 0.5% w/w of the total composition. Compounds of formula (I) may be manufactured and/or formulated separately, and in order to be used as an adjuvant these may be added to a separate agrochemical formulation at a subsequent stage, typically immediately prior to use.
The skilled man will appreciate that compositions of the invention may be in the form of a ready-to-use formulation or in concentrate form suitable for further dilution by the end user, and the concentration of agrochemical and compound of formula (I) will be adjusted accordingly. Compounds of formula (I) may be manufactured and/or formulated separately, and in order to be used as an adjuvant these may be added to a separate agrochemical formulation at a subsequent stage, typically immediately prior to use.
Compositions of the invention may be formulated in any suitable manner known to the man skilled in the art. As mentioned above, in one form a composition of the invention is a formulation concentrate which may be diluted or dispersed (typically in water) by an end-user (typically a farmer) in a spray tank prior to application.
Additional formulation components may be incorporated alongside compounds of formula (I) or compositions of the invention in such formulations. Such additional components include, for example, adjuvants, surfactants, emulsifiers, and solvents, and are well known to the man skilled in the art: standard formulation publications disclose such formulation components suitable for use with the present invention (for example, Chemistry and Technology of Agrochemical Formulations, Ed. Alan Knowles, published by Kluwer Academic Publishers, The Netherlands in 1998; and Adjuvants and Additives: 2006 Edition by Alan Knowles, Agrow Report DS256, published by Informa UK Ltd, December 2006). Further standard formulation components suitable for use with the present invention are disclosed in WO2009/130281A1 (see from page 46, line 5 to page 51, line 40).
Thus, compositions of the present invention may also comprise one or more surfactants or dispersing agents to assist the emulsification of the agrochemical on dispersion or dilution in an aqueous medium (dispersant system). The emulsification system is present primarily to assist in maintaining the emulsified agrochemical in water. Many individual emulsifiers, surfactants and mixtures thereof suitable for forming an emulsion system for an agrochemical are known to those skilled in the art and a very wide range of choices is available. Typical surfactants that may be used to form an emulsifier system include those containing ethylene oxide, propylene oxide or ethylene oxide and propylene oxide; aryl or alkylaryl sulphonates and combinations of these with either ethylene oxide or propylene oxide or both; carboxylates and combinations of these with either ethylene oxide or propylene oxide or both. Polymers and copolymers are also commonly used.
Compositions of the present invention may also include solvents, which may have a range of water solubilitites. Oils with very low water solubilities may be added to the solvent of the present invention for assorted reasons such as the provision of scent, safening, cost reduction, improvement of the emulsification properties and alteration of the solubilising power. Solvents with higher water solubility may also be added for various reasons, for instance to alter the ease with which the formulation emulsifies in water, to improve the solubility of the pesticide or of the other optional additives in the formulation, to change the viscosity of the formulation or to add a commercial benefit.
Other optional ingredients which may be added to the formulation include for example, colourants, scents, and other materials which benefit a typical agrochemical formulation.
Compositions of the invention may formulated for example, as emulsion or dispersion concentrates, emulsions in water or oil, as microencapsulated formulations, aerosol sprays or fogging formulations; and these may be further formulated into granular materials or powders, for example for dry application or as water-dispersible formulations. Preferably compositions of the invention will be formulated as, or comprised by an emulsion concentrate (EC), an emulsion in water (EW), a microcapsule formulation (CS), a suspension of particles with an emulsion of (suspoemulsion; SE), a dispersion concentrate (DC) or an oil suspension (OD).
Compositions of the invention may be used to control pests. The term “pest” as used herein includes insects, fungi, molluscs, nematodes, and unwanted plants. Thus, in order to control a pest a composition of the invention may be applied directly to the pest, or to the locus of a pest.
Compositions of the invention also have utility in the seed treatment arena, and thus may be applied as appropriate to seeds.
The skilled man will appreciate that the preferences described above with respect to various aspects and embodiments of the invention may be combined in whatever way is deemed appropriate.
Various aspects and embodiments of the present invention will now be illustrated in more detail by way of example. It will be appreciated that modification of detail may be made without departing from the scope of the invention.
The aromatic ester bis-2-ethylhexyl phthalate was tested as an adjuvant in compositions of mesotrione, in a glasshouse against four weed species. An agrochemical composition was prepared containing 0.5% v/v of the adjuvant in a track sprayer and was applied at a volume of 200 liters per hectare. Mesotrione was applied at either 60 or 120 grams per hectare. The adjuvant oils were emulsified using a small amount of the surfactant Pluronic® PE 10500, which was present in the composition at a concentration of 0.02% v/v. The weed species and their growth stage at spraying were Polygonum convolvulus (POLCO; growth stage 13), Brachiaria platyphylla (BRAPL; growth stage 13)
Digitaria sanguinalis (DIGSA; growth stage 13) and Amaranthus tuberculatus (AMATU; growth stage 13).
Each spray test was replicated three times. The efficacy of the herbicide was assessed visually and expressed as a percentage of the leaf area killed. Samples were assessed at time periods of 7, 14 and 21 days following application. The results shown below in Table 10 are mean averages over the two rates of mesotrione, three replicates, four weed species and the three assessment timings, and are compared to the efficacy of mesotrione in the absence of adjuvant and mesotrione plus the commercial tank mix adjuvant Turbocharge® (applied at 0.5% v/v).
The results show that the inclusion of either bis-2-ethylhexylphthalate or Turbocharge® increases the efficacy of the herbicide mesotrione, and that both compounds are thus effective adjuvants.
The aromatic ester bis-2-ethylhexyl phthalate was tested as an adjuvant in compositions of fomesafen, in a glasshouse against four weed species. An agrochemical composition was prepared containing 0.5% v/v of the adjuvant in a track sprayer and was applied at a volume of 200 liters per hectare. Fomesafen was applied at a rate of either 60 or 120 grams per hectare. The adjuvant oils were emulsified using a small amount of the surfactant Pluronic® PE 10500, which was present in the composition at a concentration of 0.02% v/v. The weed species and their growth stage at spraying were Chenopodium album (CHEAL; growth stage 14), Abutilon theophrasti (ABUTH; growth stage 12), Setaria viridis (SETVI; growth stage 13), and Xanthium strumarium (XANST; growth stage 12).
Each spray test was replicated three times. The efficacy of the herbicide was assessed visually and expressed as a percentage of the leaf area killed. Samples were assessed at time periods of 2, 7 and 14 days following application. The results shown below in Table 11 are mean averages over the two rates of fomesafen, three replicates, four weed species and the three assessment timings, and are compared to the efficacy of fomesafen without adjuvant and fomesafen with the commercially available adjuvant Turbocharge® (applied at 0.5% v/v).
The results show that that the inclusion of either bis-2-ethylhexylphthalate or Turbocharge® increases the efficacy of the herbicide mesotrione, and that both compounds are thus effective adjuvants.
| Number | Date | Country | Kind |
|---|---|---|---|
| 1107040.6 | Apr 2011 | GB | national |
| Filing Document | Filing Date | Country | Kind | 371c Date |
|---|---|---|---|---|
| PCT/GB12/00339 | 4/13/2012 | WO | 00 | 12/2/2013 |
