Classifications

• • C—CHEMISTRY; METALLURGY
  • C07—ORGANIC CHEMISTRY
  • C07D—HETEROCYCLIC COMPOUNDS
  • C07D307/00—Heterocyclic compounds containing five-membered rings having one oxygen atom as the only ring hetero atom
  • C07D307/77—Heterocyclic compounds containing five-membered rings having one oxygen atom as the only ring hetero atom ortho- or peri-condensed with carbocyclic rings or ring systems
  • C07D307/78—Benzo [b] furans; Hydrogenated benzo [b] furans
  • C07D307/79—Benzo [b] furans; Hydrogenated benzo [b] furans with only hydrogen atoms, hydrocarbon or substituted hydrocarbon radicals, directly attached to carbon atoms of the hetero ring
• • A—HUMAN NECESSITIES
  • A01—AGRICULTURE; FORESTRY; ANIMAL HUSBANDRY; HUNTING; TRAPPING; FISHING
  • A01N—PRESERVATION OF BODIES OF HUMANS OR ANIMALS OR PLANTS OR PARTS THEREOF; BIOCIDES, e.g. AS DISINFECTANTS, AS PESTICIDES OR AS HERBICIDES; PEST REPELLANTS OR ATTRACTANTS; PLANT GROWTH REGULATORS
  • A01N37/00—Biocides, pest repellants or attractants, or plant growth regulators containing organic compounds containing a carbon atom having three bonds to hetero atoms with at the most two bonds to halogen, e.g. carboxylic acids
  • A01N37/10—Aromatic or araliphatic carboxylic acids, or thio analogues thereof; Derivatives thereof
• • A—HUMAN NECESSITIES
  • A01—AGRICULTURE; FORESTRY; ANIMAL HUSBANDRY; HUNTING; TRAPPING; FISHING
  • A01N—PRESERVATION OF BODIES OF HUMANS OR ANIMALS OR PLANTS OR PARTS THEREOF; BIOCIDES, e.g. AS DISINFECTANTS, AS PESTICIDES OR AS HERBICIDES; PEST REPELLANTS OR ATTRACTANTS; PLANT GROWTH REGULATORS
  • A01N43/00—Biocides, pest repellants or attractants, or plant growth regulators containing heterocyclic compounds
  • A01N43/02—Biocides, pest repellants or attractants, or plant growth regulators containing heterocyclic compounds having rings with one or more oxygen or sulfur atoms as the only ring hetero atoms
  • A01N43/04—Biocides, pest repellants or attractants, or plant growth regulators containing heterocyclic compounds having rings with one or more oxygen or sulfur atoms as the only ring hetero atoms with one hetero atom
  • A01N43/06—Biocides, pest repellants or attractants, or plant growth regulators containing heterocyclic compounds having rings with one or more oxygen or sulfur atoms as the only ring hetero atoms with one hetero atom five-membered rings
  • A01N43/12—Biocides, pest repellants or attractants, or plant growth regulators containing heterocyclic compounds having rings with one or more oxygen or sulfur atoms as the only ring hetero atoms with one hetero atom five-membered rings condensed with a carbocyclic ring
• • A—HUMAN NECESSITIES
  • A01—AGRICULTURE; FORESTRY; ANIMAL HUSBANDRY; HUNTING; TRAPPING; FISHING
  • A01N—PRESERVATION OF BODIES OF HUMANS OR ANIMALS OR PLANTS OR PARTS THEREOF; BIOCIDES, e.g. AS DISINFECTANTS, AS PESTICIDES OR AS HERBICIDES; PEST REPELLANTS OR ATTRACTANTS; PLANT GROWTH REGULATORS
  • A01N43/00—Biocides, pest repellants or attractants, or plant growth regulators containing heterocyclic compounds
  • A01N43/34—Biocides, pest repellants or attractants, or plant growth regulators containing heterocyclic compounds having rings with one nitrogen atom as the only ring hetero atom
  • A01N43/36—Biocides, pest repellants or attractants, or plant growth regulators containing heterocyclic compounds having rings with one nitrogen atom as the only ring hetero atom five-membered rings
  • A01N43/38—Biocides, pest repellants or attractants, or plant growth regulators containing heterocyclic compounds having rings with one nitrogen atom as the only ring hetero atom five-membered rings condensed with carbocyclic rings
• • C—CHEMISTRY; METALLURGY
  • C07—ORGANIC CHEMISTRY
  • C07D—HETEROCYCLIC COMPOUNDS
  • C07D209/00—Heterocyclic compounds containing five-membered rings, condensed with other rings, with one nitrogen atom as the only ring hetero atom
  • C07D209/02—Heterocyclic compounds containing five-membered rings, condensed with other rings, with one nitrogen atom as the only ring hetero atom condensed with one carbocyclic ring
  • C07D209/04—Indoles; Hydrogenated indoles
  • C07D209/10—Indoles; Hydrogenated indoles with substituted hydrocarbon radicals attached to carbon atoms of the hetero ring
  • C07D209/18—Radicals substituted by carbon atoms having three bonds to hetero atoms with at the most one bond to halogen, e.g. ester or nitrile radicals
• • C—CHEMISTRY; METALLURGY
  • C07—ORGANIC CHEMISTRY
  • C07D—HETEROCYCLIC COMPOUNDS
  • C07D307/00—Heterocyclic compounds containing five-membered rings having one oxygen atom as the only ring hetero atom
  • C07D307/77—Heterocyclic compounds containing five-membered rings having one oxygen atom as the only ring hetero atom ortho- or peri-condensed with carbocyclic rings or ring systems
  • C07D307/78—Benzo [b] furans; Hydrogenated benzo [b] furans
  • C07D307/79—Benzo [b] furans; Hydrogenated benzo [b] furans with only hydrogen atoms, hydrocarbon or substituted hydrocarbon radicals, directly attached to carbon atoms of the hetero ring
  • C07D307/80—Radicals substituted by oxygen atoms
• • C—CHEMISTRY; METALLURGY
  • C07—ORGANIC CHEMISTRY
  • C07D—HETEROCYCLIC COMPOUNDS
  • C07D307/00—Heterocyclic compounds containing five-membered rings having one oxygen atom as the only ring hetero atom
  • C07D307/77—Heterocyclic compounds containing five-membered rings having one oxygen atom as the only ring hetero atom ortho- or peri-condensed with carbocyclic rings or ring systems
  • C07D307/78—Benzo [b] furans; Hydrogenated benzo [b] furans
  • C07D307/86—Benzo [b] furans; Hydrogenated benzo [b] furans with an oxygen atom directly attached in position 7
• • C—CHEMISTRY; METALLURGY
  • C07—ORGANIC CHEMISTRY
  • C07D—HETEROCYCLIC COMPOUNDS
  • C07D333/00—Heterocyclic compounds containing five-membered rings having one sulfur atom as the only ring hetero atom
  • C07D333/50—Heterocyclic compounds containing five-membered rings having one sulfur atom as the only ring hetero atom condensed with carbocyclic rings or ring systems
  • C07D333/52—Benzo[b]thiophenes; Hydrogenated benzo[b]thiophenes
  • C07D333/54—Benzo[b]thiophenes; Hydrogenated benzo[b]thiophenes with only hydrogen atoms, hydrocarbon or substituted hydrocarbon radicals, directly attached to carbon atoms of the hetero ring
  • C07D333/60—Radicals substituted by carbon atoms having three bonds to hetero atoms with at the most one bond to halogen, e.g. ester or nitrile radicals

Definitions

• This invention relates to pesticides and in particular to certain substituted acetic acid esters as compounds, to pesticidal compositions containing them and to methods of killing pests especially insects and arachnids using the compounds of the invention or compositions containing them.
• esters of chrysanthemumic and related acids have potent insecticidal properties.
• Such insecticides are known as pyrethroid insecticides.
• the naturally occurring pyrethroid insecticides are esters of derivatives of cyclopropane-carboxylic acid. Attention in recent years has been focussed on this general class of pesticides because they do not suffer from the disadvantages which have become increasingly associated with the use of organo halogen and organophosphorus pesticides.
• the present invention is based on the discovery that certain classes of fused bicyclic derivatives of substituted acetic acid form esters which have marked insecticidal properties.
• the present invention accordingly provides compou of the general formula:
• X is an oxygen or a sulphur atom, or a NH or CH 2 group
• W is an oxygen atom or a CH 2 group
• R 1 and R 2 are each independently a hydrogen or halogen (preferably chlorine or bromine) atom, or a lower alkyl aralkyl, aryl, lower alkoxy, or lower alkenyl group, or R 1 and R 2 may together be a methlenedioxy group;
• R 3 is a hydrogen, or halogen (preferably chlorine, bromine or fluorine) atom, or a lower alkyl or lower alkoxy group;
• R 4 is a lower alkyl, lower alkenyl, lower alkynyl, lower alkoxy, cyano, halogen-substituted lower alkyl, halogen-substituted lower alkenyl group, or a C 3 to C 5 alicyclic group; and R 5 is a group of one of the following formulae:
• A is a hydrogen atom, or a cyano group, or a -C ⁇ CH group, or group;
• R 6 and R 7 are each independently a hydrogen atom, or a lower alkyl or lower alkenyl group;
• Z is an oxygen or a sulphur atom, or a -CH 2 - or -CO- group
• Y is a hydrogen atom, or a lower alkyl, lower alkenyl, lower alkynyl or an aryl or furyl group which is either unsubstit ⁇ ted, or is substituted by one or more lower alkyl, lower alkenyl or lower alkoxy groups or halogen atoms;
• R 8 is a hydrogen atom, or a methyl group
• R 9 and R 10 are each independently a hydrogen atom, or a lower alkyl group
• B 1 , B 2 , B 3 , B 4 are each independently a hydrogen, or halogen atom, or a methyl group;
• D 1 and D 2 are each independently a halogen atom (preferably fluorine or chlorine) or a methyl group, and each n may be independently 0, 1 or 2;
• the invention particularly includes compounds of the formu
• R 1 , R 2 , R 3 , R 4 , R 5 and X are as defined above.
• R 1 R 2 R 3 R 4 and R 5 are as defined above .
• Alcohols of the formula R 5 0H, where R 5 is as defined above, are generally known and have been suggested or used as the alcohol radical in synthetic pyrethroids and substituted acetate esters having pesticidal activity.
• R 5 is a group of one of the formulae:
• lower alkyl lower alkoxy
• lower alkenyl lower alkynyl groups
• lower alkynyl groups these terms refer to such groups having up to 4 carbon atoms. Those groups with 3 or 4 carbon atoms can be straight or branched chain groups.
• lower alkyl and lower alkoxy we prefer among “lower alkyl” and “lower alkoxy” groups to use methyl, ethyl, iso-propyl, iso-butyl or tert- butyl and the corresponding alkoxy groups.
• the lower alkenyl groups can be primary, or secondary and the double bond may be in any position in the chain.
• the lower alkynyl groups are preferably ethynyl or 3-propynyl groups.
• dihalo especially di chloro or difluoro, vinyl groups
• aryl groups we prefer phenyl groups and by the term "aralkyl group” we mean one based on a C 1 to C 4 alkyl chain and prefer the aralkyl group to be benzyl.
• the compounds of the present invention contain an asymmetric centre at the ⁇ -carbon atom of the carboxylic acid moiety. They may include other asymmetric centres elsewhere in the molecule.
• the pesticidal activity of the various possible isomers including enantiomers epimers and diastereoisomers will be different. It is not generally possible to predict which isomers are likely to be most active or by how much.
• the present invention includes the racemic and other mixtures that will usually be obtained by non-stereospecific synthesis as well as particular isomers or mixtures having an artificially enhanced proportion of a particular isomer(s) obtained by separation or stereospecific synthesis
• the pesticidal activity of the compounds of the invention which we have tested is such that we infer that they generally have activities at least comparable with those described in Sumitomo's U.K. Patent No. 1439615.
• the compounds of the invention can be made by conventional synthetic routes. It is generally convenient to conduct the synthesis so as to produce the acid and alcohol corresponding to the ester, or reactive derivatives of the acid and/or alcohol, and to react these together to form the ester. For convenience in the reaction schemes outlined below the acid of the formula Ila or lIb:
• esters of general formula (I) may be prepared by any of the following esterification methods:- (a) reaction of an acid halide with an alcohol
• the acid halide is allowed to react with the alcohol at 0oC to 40oC using an acid acceptor, for example, an organic tertiary amine base such as pyridine or triethylamine.
• an acid acceptor for example, an organic tertiary amine base such as pyridine or triethylamine.
• the acid halide may be any type of acid halide but the acid chloride is generally preferred.
• the presence of an inert solvent one which is inert to the reactants and the ester product
• Reaction (b) The acid is allowed to react with the alcohol using an appropriate dehydrating agent, for example dicyclohexylcarbodiimide, in an appropriate inert solvent, such as toluene, benzene or petroleum ether, at temperatures from 0°C to the boiling point of the solvent used.
• Reaction (c) An appropriate acid anhydride is allowed to react with the alcohol at room or elevated temperature without using specific aids. In this case it is preferred to heat the reaction system and to use an inert solvent such as toluene, xylene in order to ensure smooth reaction.
• ester exchange reaction is carried out between an ester of an appropriate acid and a low boiling point alcohol, e.g. methanol, or ethanol, with an appropriate alcohol by means of heating the ester and the alcohol in the presence of an acidic catalyst such as P-toluene sulphonic acid, or in the presence of a basic catalyst such as an alkali metal alkoxide corresponding to the low boiling alcohol of the ester used, or sodium hydride in an inert solvent such as toluene, while removing the low boiling alcohol liberated during the reaction from the reaction system by a fractional distillation column.
• an acidic catalyst such as P-toluene sulphonic acid
• a basic catalyst such as an alkali metal alkoxide corresponding to the low boiling alcohol of the ester used, or sodium hydride in an inert solvent such as toluene
• Reaction (e) The halide or sulphoxylate derivative of the alcohol and an appropriate salt of an appropriate acid, usually an alkali metal salt, a silver salt or an organic tertiary base salt are allowed to react.
• the salts may be formed in situ by adding simultaneously the acid and the corresponding base to the re action system.
• a solvent such as benzene, acetone or dimethylformaraide is preferably used, and the reaction is preferably carried out by heating the reaction system at or below the boiling point of the solvent used.
• Preferred halides of the alcohol are the chlorides and the bromides.
• An appropriate ester is allowed to react with an alkyl halide or sulphoxylate in the presence of a basic catalyst for example sodium amide in an inert solvent, or in the presence of alkali hydroxide in the presence of a phase transfer catalyst for example a quaternary ammonium salt, a phosphonium salt or a crown ether.
• a basic catalyst for example sodium amide in an inert solvent
• alkali hydroxide in the presence of a phase transfer catalyst for example a quaternary ammonium salt, a phosphonium salt or a crown ether.
• the acids of general formula (Ila) may be prepared by one or more of the following routes.
• F 1 , R 1 , R 2 , R 3 , and R 4 are as defined above, Et means ethyl and R means alkyl such as ethyl, Hal means halogen such as bromine or chlorine.
• the substituted acetonitrile starting materials may be made by one or more of the following subsidiary routes:
• the substituted ketones used as starting materials in routes (ii), (iii), (iv) and (v) may be made by conventional methods, or, in the case of substituted or unsubstituted benzofuran-2-yl ketones by the following subsidiary route:
• the acids of general formula lIb may be prepared by one of more of the following routes:
• ketones of formula F 2 COR 4 may be made by one or more of the following subsidiary routes:
• Step 1 The appropriate nitrile may be alkylated with an appropriate halide or sulphoxylate of formula R 4 -J (J being a halide or sulphoxylate radical) in an inert solvent (for example, an ether, tetrahydrofuran, benzene, toluene or liquid ammonia when sodamide or the like is used as base as described below) in the presence of a base such as an alkali metal, alkali metal hydride, alkali metal amide or the like, at room temperature or elevated temperature; or the appropriate nitrile may be alkylated with an appropriate halide or sulphoxylate (R 4 -J) using aqueous alkali (for example, an alkali metal hydroxide) and an inert solvent (for example, an ether, tetrahydrofuran, benzene, toluene,
• an inert solvent for example, an ether, tetrahydrofuran, benz
• the benzofuranone starting compound (substituted or unsubstituted) can be made by conventional synthetic methods e.g. those described in "The Chemistry of Heterocyclic Compounds” edited by A. Weisberger and E. C. Taylor Volume 29 "Benzofurans” by Ahmed Mustafa (published by J. Wiley and Sons, Wiley Interscience, 1974) chapter 5; Benzofuranones.
• Step 2 The appropriate nitrile may be hydrolyzed by one of the well-known methods for such reactions for example by heating the nitrile with a mineral acid, or by heating the nitrile with an alkali metal hydroxide solution or by treating with hydrogen peroxide, followed by reaction with nitrous acid, or by treating with sulphuric acid.
• Step 5 Oxidation by silver hydroxide, prepared in situ, in water.
• Ethoxymethylenetriphenylphospohorane generated in situ from the triphenylphosphonium halide by base such as butyl lithium in ether, phenyl lithium in tetrahydrofuran or sodium ethoxide in ethanol.
• the phosphonium salt may be prepared from triphenylphosphine and the appropriate aldehyde. Step 9
• Step 11 Treatment with a catlytic amount of potassium hydrogen sulphide, lithium trifluoroacetate or lithium perchlorate in refluxing toluene.
• Step 16 Normal procedure for Grignard reagent formation, Magnesium in anhydrous diethyl ether.
• Step 19 Reaction with ⁇ -bromo ester in the presence of base in a mixture of benzene and dimethylformamide as the solvent.
• Reduction for example, using zinc and concentrated hydrochloric acid.
• the acids produced by routes (i) to (xiv) can be converted to reactive derivatives for esterification by known methods. It will be appreciated that the products of some intermediate stages in these routes can be converted into suitable reactive derivatives without intermediate formation or isolation of the free acid. Also some intermediates, notably the product of step 13, are esters of the acid typically ethyl esters and can, accordingly, be used as reactive derivatives of the acid e.g. by ester exchange.
• the compounds of this invention in practice are used as compositions comprising the active ingredient in combination with a diluent and commonly including other additives.
• the invention accordingly includes an insecticidal composition comprising an insecticidal concentration or quantity of a compound of the invention in combination with a diluent.
• the diluent will be a physical carrier to facilitate delivery of the pesticide to its site of action.
• the diluent can be a solvent, a liquid in which the pesticide is dispersible, an aerosol medium or a solid carrier. Dissolved in a suitable solvent such as a volatile organic solvent or an oil the composition can be used as a spray, especially a low volume spray.
• Such a solution can be used in the formulation of emulsions or dispersions as can the compounds themselves.
• emulsions are as used in both low and high volume sprays.
• surface active agents such as dispersants and emulsion (and dispersion) stabilizers will usually be included.
• emulsifiable concentrates in which the insecticidal compound is in combination with a surface active agent and usually in solution in a suitable solvent such that an emulsion for use can be obtained by adding the emulsion continuous phase e.g. water, and, if necessary mixing.
• Solid carriers include dusts and powders e.g. wettable powders and moulded or mouldable particulate solids.
• the insecticidal compositions of the invention include compositions containing active ingredients other than the compound(s) of this invention.
• one or more compounds of the invention can be combined with other insecticides or other pesticides. This can be done to combine the pesticidal effects to obtain a broader spectrum of effectiveness, to take advantage of different modes of pesticidal action, to provide greater specificity, or to achieve enhanced activity.
• the composition may include a synergist to enhance the pesticidal activity of the composition. Typically, in insecticides, such synergists act to inhibit metabolic deactivation of the insecticidal component(s) of the composition. Piperonyl butoxide is a widely used synergist in insecticidal compositions and can be used in the compositions of the present invention.
• Typical pesticidal formulations of compositions containing the compounds of the invention as an active ingredient include (all percentages by weight on the total composition unless otherwise specified): Aerosol Compound of invention 0.02 to 2% Synergist (e.g. piperonyl butoxide) 0.1 to 5%
• a suitable solvent such as an aromatic hydrocarbon and combined with an aerosol propellant e.g. liquefied petroleum gas(L.P.G.) such as butane or halogenated e.g. fluorinated or fluorinated and chlorinated, hydrocarbons such as CCl 2 F 2 , CHCl 2 F, CCl 3 F and CH 3 .CClF 2 (these and similar materials are readily available commercially e.g. under the Trade Marks Freon, Frigen and Arcton among others).
• LPG liquefied petroleum gas
• the proportion of propellant in the composition will typically be: 10 to 40%
• the solution of the compound of the active ingredients may therefore comprise:
• the active ingredients as a solution e.g. in an aromatic hydrocarbon may be dispersed as an emulsion in a medium such as water prior to inclusion in the aerosol with the propellant.
• a small amount of emulsifier e.g. a non ionic surfactant in a concentra tion of up to 1% by weight on the emulsion, will usually be included in such an emulsion.
• the emulsion will typically be used in proportions similar to that of the solution.
• the concentration of the active ingredients in the solution will typically be from 0.12 to 10% by weight on the solution where the solution is used directly. Where the solution is incorporated in the aerosol as an emulsion the concentration may be higher than 10% e.g. up to about 35% by weight on the solution (or saturation).
• the proportion of propeleant in the composition will typically be: 60 to 80%
• the solution of the active ingredients may therefore comprise:
• concentration of the active ingredients in the solution will typically be in the range 0.3 to 20% by weight on the solution, but where relatively large proportions of propellant are used the upper limit of concentration may be as high as 35% by weight on the solution (or saturation).
• Surfactant preferably non-ionic 0.5 to 10% e.g. of the "Tween” type
• the suspending and wetting agents can be those used conventionally.
• Typical wetting agents include sodium dodecylbenzene sulphonate and suspending agents include methyl cellulose.
• Oil e.g. petroleum oil 99 to 5%
• the nature of the oil will depend on the particular end use envisaged. Thus, for ultra low volume spraying the oil will be a heavy petroleum oil e.g. of the "Rissella" type, but for end uses involving higher volumes the oil will typically be a medium or light petroleum oil. Mixtures of oils can be used if desire Conventional other ingredients of oil base composition can be included e.g. synergists, other insecticides an surfactants.
• Thionyl chloride (0.60 g., 0.005 mol) was added to a solution of ⁇ -isopropylbenzofuran-2-acetic acid (1.0 g., 0.005 mol), dimethylformamide (1 drop) in dry toluene (10 cm ) and the mixture was heated at 80o for 2.5 hr. Unchanged thionylchloride and toluene were removed under reduced pressure to leave a residue of ⁇ -isopropylbenzofuran-2-acetyl chloride which was used in the next stage without further purification.
• silica using toluene as the eluant was carried out and the component with R f 0.51 was isolated as m-phenoxybenzyl ⁇ -isopropylbenzo[b]thiophene-3-acetate (0.41 g., 0.00093 mol, 93.2%).
• Example 5 The title compound was made by the method of Example 5 by substituting 5-chloro- ⁇ -isopropylbenzo[b] thiophene-3-acetyl chloride obtained as an intermediate in Example 6 , for the ⁇ -isopropylbenzo hiophene-3-acetyl chloride used in Example 5.
• EXAMPLE 8 m-Phenoxybenzyl 5-chloro- ⁇ -isopropylbenzofuran-2- acetate
• the title compound was made by the method of Example 1 by substituting 5-chlorobenzofuran-2-acetonitrile for the benzofuran-2-acetonitrile used in Example 1.
• Example 5 The title compound was made by the method of Example 5 by substituting 5-chloro- ⁇ -isopropylbenzofuran-2-acetyl chloride, obtained as an intermediate in Example 8, for the ⁇ -isopropylbenzo [b] thiophene-3-acetyl chloride used in Example 5.
• EXAMPLE 10 m-Phenoxybenzyl ⁇ -isopropylbenzofuran-3-acetate
• Example 1 The title compound was made by the method of Example 1 by substituting benzofuran-3-acetonitrile for the benzofuran-2-acetonitrile used in Example 1.
• EXAMPLE 12 m-Phenoxybenzyl 5-chloro- ⁇ -isopropylbenzofuran- 3-acetate
• the title compound was prepared by the method of Example 1 by substituting 5-chlorobenzofuran-3-acetonitrile (prepared by the same method as described in Aust. J. Chem. 1975, 28, 1097 for the preparation of benzofuran-3-acetonitrile) for the benzofuran-2-aceto- nitrile used in Example 1.
• Example 14 The title compound was made by the method of Example 5 by substituting 5-chloro- ⁇ -isopropylbenzofuran-3-acetyl chloride, obtained as an intermediate in Example 12, for the ⁇ -isopropylbenzo[b]thiophene-3-acetyl chloride used in Example 5.
• EXAMPLE 14 ⁇ -Cyano-m-phenoxybenzyl ⁇ -isopropyl-7-methyl benzofuran-3-acetate
• Example 12 by substituting 7-methylbenzofuran-3-acetonitrile for the 5-chloro benzofuran-3-acetonitrile used in Example 12) for the ⁇ -isopropylbenzo[b] thiophene-3-acetyl chloride used in Example 5.
• the ester was prepared in 50.1% yield using the same method as Example 1(d), TLC/silica/toluene, R f
• Example 2 The title compound was prepared by the method of Example 1(d) by substituting ⁇ -t-butylbenzofuran-2-acetyl chloride, obtained as an intermediate in Example
• Example 5 The title compound was made by the method of Example 5 by substituting ⁇ -isopropyl-7-methoxybenzofuran-2-acetyl chloride (made by the method of Example 1 by substituting ⁇ -isopropyl-7-methoxybenzofuran-2-acetonitrile for the ⁇ -isopropylbenzofuran-2-acetonitrile of Example l) for the ⁇ -isopropylbenzo[b]thiophene-3-acetyl chloride used in Example 5.
• Example 18 The title compound was made by the method of Example 18(e) substituting 5-benzyl-3-furylmethanol for the ⁇ -cyano-m-phenoxybenzyl alcohol used in Example 18(e).
• EXAMPLE 20 ⁇ -Cyano-m-phenoxybenzyl ⁇ -ethyl-7-methoxy benzofuran-2-acetate
• the title compound was made by the method of Example 5 by substituting ⁇ -ethyl-7-methoxybenzofuran-2-acetyl chloride (prepared by the method of Example 1 substituting f7-methoxybenzofuran-2-acetonitrile and iodoethane for the benzofuran-2-acetonitrile and 2-iodopropane, respectively used in Example 1) for the ⁇ -isopropylbenzofbj thiophene-3-acetyl chloride used in Example 5.
• EXAMPLE 21 ⁇ -Cyano-m-phenoxybenzyl 2
• Example 5 The title compound was made by the method of Example 5 by substituting 2,3-dihydro- ⁇ -ethyl-7-methoxybenzofuran-2-acetyl chloride- (prepared from the acid in the usual manner).
• the acid was made by catalytic hydrogenation of ⁇ -ethyl-7-methoxybenzofuran-2-acetic acid, an intermediate from Example 20), for the ⁇ -isopropylbenzo[b]thiophene-3-acetyl chloride used in Example 5.
• Example 5 by substituting 5-chloro- ⁇ -isopropyl-7-methylbenzofuran-3-acetyl chloride [prepared by the method of Example 1 by substituting 5-chloro-7-methylbenzofuran-3-acetonitrile (itself prepared by the method described for this class of compound in J. Aust. Chem. 1975, 28, 1097, c.f. Example 12) for the benzofuran-2-acetonitrile used in Example I] for the ⁇ -isopropylbenzo[b]thiophene-3-acetyl chloride used in Example 5.
• TESTS OF ACTIVITY The insecticidal activities of the compounds of the Examples has been shown by the following tests in three species of insects, namely Aedes aegypti, Musca domestica, and Blattella germanica.
• Table 1 shows the results obtained for compounds of the Examples. The results are all expressed as activities relative to the activity of Resmethfin
• Resmethrin is 5-benzyl-3-furylmethylchrysanthemum ate and is a synthetic pyrethoid insecticide developed by the N.R.D.C. see e.g. U.K. Patent Specification No. 1,168,797. It has an activity about 20 times that of natural pyrethrum and has been used as an insecticide and as a reference substance in assessing the insecticidal activity of other compounds.
• a 9.0 cm. square of cabbage leaf was dipped for 4 seconds in the aqueous suspension of the test compound, and allowed to dry.
• the leaf was placed on filter paper in a Petri dish (9.0 cm).
• Five 3rd instar larvae were placed on the leaf, and the dish was placed in a polythene bag containing a wet cotton-wool pad. Knockdown was recorded after 24 hours.
• Table 2 shows the results obtained for some of the compounds of the Examples.
• Phytotoxicity is an important feature when the insecticide is applied to foliage. On application of 100 ppm of fenvalerate to lettuce, cucumber and dwarf French beans, phytotoxicity was observed.
• Photostability is an important feature when the insecticide is applied to foliage. Natural pyrethrum and many synthetic pyrethroids have low photostability, and hence have restricted use as plant protection agents The compounds of this invention exhibit considerably greater photostability than many other pyrethroids, for example, resmethrin.
• a deposit of selected Examples and resmethrin was exposed to a light source and tested at increasing time intervals. Example number 1 had a half-life 5 times greater than resmethrin, and Example number 11 had a half-life 14.5 times greater than resmethrin.

Landscapes

• Chemical & Material Sciences (AREA)
• Organic Chemistry (AREA)
• Life Sciences & Earth Sciences (AREA)
• Dentistry (AREA)
• Wood Science & Technology (AREA)
• Plant Pathology (AREA)
• Health & Medical Sciences (AREA)
• Engineering & Computer Science (AREA)
• Agronomy & Crop Science (AREA)
• General Health & Medical Sciences (AREA)
• Pest Control & Pesticides (AREA)
• Zoology (AREA)
• Environmental Sciences (AREA)
• Agricultural Chemicals And Associated Chemicals (AREA)
• Furan Compounds (AREA)
• Indole Compounds (AREA)
• Organic Low-Molecular-Weight Compounds And Preparation Thereof (AREA)

Priority Applications (1)

Applications Claiming Priority (2)

Publications (1)

Family

ID=10499655

Family Applications (1)

Country Status (5)

Cited By (1)

Citations (2)

• 1979
  • 1979-09-11 WO PCT/GB1979/000149 patent/WO1980000563A1/en not_active Ceased
  • 1979-09-11 JP JP50143279A patent/JPS55500700A/ja active Pending
  • 1979-09-13 BE BE0/197134A patent/BE878773A/fr not_active IP Right Cessation
  • 1979-09-14 IT IT25752/79A patent/IT1123179B/it active
• 1980
  • 1980-04-09 EP EP79901080A patent/EP0020391A1/en not_active Withdrawn

Patent Citations (2)

Also Published As

Similar Documents

Legal Events