GB2181125A

GB2181125A - Pesticidal benzoylurea compounds

Info

Publication number: GB2181125A
Application number: GB08524545A
Authority: GB
Inventors: Martin Anderson
Original assignee: SHELL INT RESEARCH; Shell Internationale Research Maatschappij BV
Current assignee: SHELL INT RESEARCH; Shell Internationale Research Maatschappij BV
Priority date: 1985-10-04
Filing date: 1985-10-04
Publication date: 1987-04-15
Also published as: GB8524545D0

Abstract

Compounds of the general formula <IMAGE> in which each of A and B independently represents a halogen atom or an alkyl group; m is 0 or 1; each of R1 and R2 independently represents an alkyl group optionally substituted by one or more moieties selected from halogen, alkoxy, alkoxycarbonyl, haloalkoxycarbonyl, alkylcarbonyl, haloalkylcarbonyl, alkylsulphonyl and haloalkylsulphonyl; X represents a halogen atom or a cyano, nitro, alkyl or haloalkyl group; each of Y and Z independently represents a halogen atom or a cyano, nitro or haloalkyl group; n is 0, 1, 2, 3 or 4; and p is 0, 1 or 2, have insecticidal and acaricidal activity. The invention also relates to certain intermediates for use in the preparation of these compounds.

Description

SPECIFICATION Pesticidal benzoylurea compounds The present invention relates to benzoylurea compounds having pesticidal, especially insecticidal and acaricidal, activity.

The invention provides a compound of the general formula

in which each of A and B independently represents a halogen atom or an alkyl group; m is O or 1; each of R, and R2 independently represents an alkyl group optionally substituted by one or more moieties selected from halogen, alkoxy, alkoxycarbonyl, haloalkoxycarbonyl, alkylcarbonyl, haloalkylcarbonyl, alkylsulphonyl and haloalkylsulphonyl; X represents a halogen atom or a cyano, nitro, alkyl or haloalkyl group; each of Y and Z independently represents a halogen atom or a cyano, nitro or haloalkyl group; n is O, 1, 2, 3 or 4; and p is O, 1 or 2.

Except where otherwise stated, throughout this Specification and claims, any alkyl moiety preferably has up to 6, especially up to 4, carbon atoms. In relation to the groups A, B and X, a preferred alkyl group is methyl. In relation to the groups X, Y and Z a preferred haloalkyl group is trifluoromethyl. Halogen atoms may be fluorine, chlorine, bromine or iodine atoms, with fluorine and chlorine being preferred. When n or p is greater than 1, the substituents X or Z present may be the same or different.

Preferably each of A and B independently represents a fluorine or chlorine atom or a methyl group. Most preferably, A is a fluorine atom, m is 1 and B is a fluorine or chlorine atom, preferably in the 6-position of the phenyl ring (A of course being in the 2-position).

Preferably X represents a fluorine or chlorine atom or a methyl group. Thus typically (X)n may be 4 fluorine atoms, 2 fluorine atoms and two chlorine atoms, or a fluorine atom and three chlorine atoms. Preferably at least one moiety X is a fluorine atom ortho to the nitrogen linkage.

The subscript n is preferably 1.

Preferably Y represents a chlorine atom or a nitro, cyano or trifluoromethyl group. A trifluoromethyl group Y is especially preferred.

Preferably Z represents a chlorine atom or a cyano or nitro group. Preferably p is O or 1.

Most preferably Z represents a chlorine atom and p is 1; such a chlorine atom is preferably in the position ortho to the oxygen linkage.

Preferably, R1 and R2 are identical. Whether identical or different, it is preferred that at least one of R1 and R2, and preferably both of them, is an unsubstituted alkyl group.

The invention also provides a process for the preparation of a compound of the general formula I, which comprises reacting a compound of the general formula

with a compound of the general formula

in which A, B, m, X, Y, Z, R1, R2, n and p have the meanings given for the general formula I.

The reaction is suitably carried out in the presence of a solvent. Suitable solvents are aromatic solvents such as benzene, toluene, xylene, or chlorobenzene, hydrocarbons such as petroleum fractions, chlorinated hydrocarbons such as chloroform, methylene chloride or dichloroethane, and ethers such as diethyl ether, dibutyl ether, or dioxan. Mixtures of solvents are also suitable.

Preferably the reaction is carried out at a temperature from 0 C to 100"C, suitably ambient temperature. Preferably the molar ratio of isocyanate to amine is from 1:1 to 2:1. Preferably the reaction is carried out under anhydrous conditions.

The compounds of formula II are themselves novel and constitute a further aspect of the invention; they may be prepared by reacting a compound of the general formula

with a compound of the general formula

in which Hal represents a halogen atom.

The reaction between the compounds of formulae IV and V is preferably carried out in the presence of an inert solvent, for example a hydrocarbon or chlorinated hydrocarbon, and the reaction temperature is preferably in the range of from 0 to 100"C, preferably 10 to 30"C. The reaction is suitably carried out in the presence of an inorganic or organic base. Preferably an amine such as triethylamine is used.

The compounds of formula IV may be prepared by reacting a compound of general formula

with a compound of the general formula

in which X, n, Y, Z, and p have the meanings given for the compound of general formula IV.

The reaction between the compounds of formulae VI and VII is preferably carried out in the presence of an inert solvent, for example a polar aprotic solvent such as dimethylsulphoxide or dimethylformamide, in the presence of a base, for example an alkali metal hydroxide, alkoxide or carbonate, or an organic base. The reaction temperature is suitably in the range of from 0 to 1500C, preferably 30 to 100"C.

The compounds of general formula V may be prepared by reacting a sulphenyl halide compound of general formula S(Hal)2 with a compound of general formula

The reaction is preferably carried out in the presence of an inert solvent, for example a hydrocarbon or halogenated hydrocarbon and a base, preferably an organic base such as pyridine, and may be carried out at a temperature from - 10 to 100"C.

The compounds of the general formula I exhibit pesticidal, for example insecticidal and acaricidal, activity. Accordingly the invention also provides a pesticidal composition comprising a compound of the general formula I together with a carrier. The invention further provides a method of combating pests at a locus, which comprises applying to the locus a pesticidal compound or composition according to the invention.

A carrier in a composition according to the invention is any material with which the active ingredient is formulated to facilitate application to the locus to be treated, which may for example be a plant, seed or soil, or to facilitate storage, transport or handling. A carrier may be a solid or a liquid, including a material which is normally gaseous but which has been com pressed to form a liquid, and any of the carriers normally used in formulating pesticidal compositions may be used. Preferably compositions according to the invention contain 0.5 to 95% by weight of active ingredient.

Suitable solid carriers include natural and synthetic clays and silicates, for example natural silicas such as diatomaceous earths; magnesium silicates, for example talcs; magnesium aluminium silicates, for example attapulgites and vermiculites; aluminium silicates, for example kaolinites, montomorillonites and micas; calcium carbonate; calcium sulphate; ammonium sulphate; synthetic hydrated silicon oxides and synthetic calcium or aluminium silicates; elements, for example carbon and sulphur; natural and synthetic resins, for example coumarone resins, polyvinyl chloride, and styrene polymers and copolymers; solid polychlorophenols; bitumen; waxes; and solid fertilisers, for example superphosphates.

Suitable liquid carriers include water; alcohols, for example isopropanol and glycols; ketones, for example acetone, methyl ethyl ketone, methyl isobutyl ketone and cyclohexanone; ethers; aromatic or araliphatic hydrocarbons, for example benzene, toluene and xylene; petroleum fractions, for example kerosine and light mineral oils; chlorinated hydrocarbons, for example carbon tetrachloride, perchloroethylene and trichloroethane. Mixtures of different liquids are often suitable.

Agricultural compositions are often formulated and transported in a concentrated form which is subsequently diluted by the user before application. The presence of small amounts of a carrier which is a surface-active agent facilitates this process of dilution. Thus preferably at least one carrier in a composition according to the invention is a surface-active agent. For example the composition may contain at least two carriers, at least one of which is a surface-active agent.

A surface-active agent may be an emulsifying agent, a dispersing agent or a wetting agent; it may be nonionic or ionic. Examples of suitable surface-active agents include the sodium or calcium salts of polyacrylic acids and lignin sulphonic acids; the condensation of fatty acids or aliphatic amines or amides containing at least 12 carbon atoms in the molecule with ethylene oxide and/or propylene oxide; fatty acid esters of glycerol, sorbitan, sucrose or pentaerythritol; condensates of these with ethylene oxide and/or propylene oxide; condensation products of fatty alcohol or alkyl phenols, for example poctylphenol or poctylcresol, with ethylene oxide and/or propylene oxide; sulphates or sulphonates of these condensation products; alkali or alkaline earth metal salts, preferably sodium salts, of sulphuric or sulphonic acid esters containing at least 10 carbon atoms in the molecule, for example sodium lauryl sulphate, sodium secondary alkyl sulphates, sodium salts of sulphonated castor oil, and sodium alkylaryl sulphonates such as dodecylbenzene sulphonate; and polymers of ethylene oxide and copolymers of ethylene oxide and propylene oxide.

The compositions of the invention may for example be formulated as wettable powders, dusts, granules, solutions, emulsifiable concentrates, emulsions, suspension concentrates and aerosols. Wettable powders usually contain 25, 50 or 75% w of active ingredient and usually contain in addition to solid inert carrier, 3-10% w of a dispersing agent and, where necessary, 0-10% w of stabiliser(s) and/or other additives such as penetrants or stickers. Dusts are usually formulated as a dust concentrate having a similar composition to that of a wettable powder but without a dispersant, and are diluted in the field with further solid carrier to give a composition usually containing -10% w of active ingredient. Granules are usually prepared to have a size between 10 and 100 BS mesh (1.676-0.152 mm), and may be manufactured by agglomeration or impregnation techniques.Generally, granules will contain -75% w active ingredient and 0-10% w of additives such as stabilisers, surfactants, slow release modifiers and binding agents. The so-called "dry flowable powders" consist of relatively small granules having a relatively high concentration of active ingredient. Emulsifiable concentrates usually contain, in addition to a solvent and, when necessary, co-solvent, 10-50% w/v active ingredient, 2-20% 2-20% w/v emulsifiers and 0-20% w/v of other additives such as stabilisers, penetrants and corrosion inhibitors.Suspension conentrates are usually compounded so as to obtain a stable, non-sedimenting flowable product and usually contain 10-75% w active ingredient, 0.5-15% w of dispersing agents, 0.1-10% w of suspending agents such as protective colloids and thixotropic agents, 0-10% w of other additives such as defoamers, corrosion inhibitors, stabilisers, penetrants and stickers, and water or an organic liquid in which the active ingredient is substantially insoluble; certain organic solids or inorganic salts may be present dissolved in the formulation to assist in preventing sedimentation or as anti-freeze agents for water.

Aqueous dispersions and emulsions, for example compositions obtained by diluting a wettable powder or a concentrate according to the invention with water, also lie within the scope of the invention. The said emulsions may be of the water-in-oil or of the oil-in-water type, and may have a thick 'mayonnaise'-like consistency.

The composition of the invention may also contain other ingredients, for example other compounds possessing pesticidal, herbicidal, or fungicidal properties. The compounds of the invention are especially useful when applied in admixture with other insecticides, especially organophosphates and pyrethroids. Mixtures with the commercial products fenvalerate, permeth rin, cypermethrin, deltamethrin and alphamethrin are especially useful.

The following Examples illustrate the invention. Example 1 illustrates the preparation of the intermediate of the general formula IV while Examples 2-4, 5 and 6 illustrate the preparation of compounds of the general formula I.

Example 1 Preparation of 2-fluoro-4-[2-chloro-4-(trifluoromethyl)phenoxy]ani/ine A solution of 2-fluoro-4-hydroxyaniline (7.19) and potassium hydroxide (3.79, 85% pure) in dimethylsulphoxide (25ml) was heated to 80"C and treated with a solution of 1,2-dichloro-4 (trifluoromethyl)benzene (10.99) in dimethylsulphoxide (10ml). The mixture was stirred at 90-95"C for 20 hours, after which time it was diluted with a mixture of water and dichloromethane. The organic phase was dried over sodium sulphate and evaporated down to give 3.69 of.

the crude desired product as a brown oil.

Chromatography over silica gel using toluene/petroleum ether (4:1 ratio) gave 1.1 g of the pure amine as a yellow oil.

Example 2 Preparation of di(n-propyl)aminosulphenyl chloride Sulphur dichloride (22.79) in dichloromethane (100ml) was cooled to -5"C and a solution of pyridine (17.49) in dichloromethane (50ml) was added, over 30 minutes, while the temperature was maintained between -5 and 0 C. The resulting solution was stirred for 15 minutes and a solution of di(n-propyl)amine (20.29) dissolved in dichloromethane (50ml) was added, over 30 minutes, while the temperature was maintained between -5 and 0 C. The resulting solution was stirred for 2 hours, whilst the temperature was allowed to rise to ambient. The solution was filtered and the solvent evaporated off. Diethyl ether was added (150ml), the resulting solution filtered, and the filtrate evaporated.Distillation of the resiude yielded the title compound, (28.79), b.p. 94-5"C/15mm.

Example 3 Preparation of [4-[2-chloro-4-(trifluoromethyl)phenoxy]-2-fluorophenyl][[di(n-propyl)amino]thio]amine A solution of the compound prepared in Example 2 (3.79) in diethyl ether (25ml) was added, over 20 minutes at 15-20"C, to a solution of triethylamine (2.2g) and the compound prepared in Example 1 (6.1 g) in diethyl ether (100my). The resulting solution was stirred at ambient temperature for 3 hours. Diethyl ether was added (100ml), the solution was washed with water, and dried. The solvent was removed by evaporation, and the product was used without further purification in the following Example.

Example 4 Preparation of N[[[4-[2-chloro-4-(trifluoromethyl)phenoxy]-2-flurophenyl][[di(n-propyl)amino]thio]ami- no]carbonyl]-2, 6-difluorobenzamide 2,6-Difluorobenzoyl isocyanate (2.69) in diethyl ether (15ml) was added over 30 seconds to the product of Example 3 (5.4g). The solution was stirred at ambient temperature for 2- hours after which a slight precipitate formed. Petroleum ether (50ml) was added, and the resulting suspension cooled in a freezer (-5 to 0 C) for 3 hours. The precipitate which formed was filtered off and recrystallised from a diethyl ether/petroleum ether solvent(1:1 v/v), yielding 2.39 of crystals, m.p. 1 18-1210C.

Analysis: C H N Calculated (%) 52.3 3.9 6.8 Found (%) 52.5 3.4 6.7 Example 5 Preparation of N[[[4-[2-chloro-4-(trifluorometh yl)phenoxy]-2-flurophen ylff[diisoprop ylamino]thio]ami- no]carbonyl]-2, 6-difluorobenzamide The title compound was prepared in a similar manner to the compound of Example 4. The intermediate compound di(isopropyl)aminosulphenyl chloride boiled at 92-4"C/20mmHg. The title compound was a solid which melted at 147-9"C.

Analysis: C H N Calculated (%) 52.3 3.9 6.8 Found (%) 52.7 3.9 6.6 Example 6 Preparation of N[[[4-[2-chloro-4-(trifluoromethyl)phenoxy]-2-flurophen ylff[diethylamino]thio]amino]- carbonyl]-2,6-difluorobenzamide The title compound was prepared in a similar manner to the compound of Example 4. The intermediate compound diethylaminosulphenyl chloride boiled at 60-620C/ 11 mmHg. The further intermediate compound, [4-[2-chloro-4-(trifluoromethyl)phenoxy)-2-fluorophenyl][[diethylamino]th- io]amine was isolated, as a solid, m.p. 58-60"C. The title compound was a solid which melted at 140-2"C.

Analysis: C H N Calculated (%) 50.7 3.4 7.1 Found (%) 50.4 3.2 6.7 Example 7 Insecticidal Activity.

The insecticidal activity of the compounds of the invention was determined in the following tests, employing the insects Spodoptera littoralis (S.l.) and Aedes aegypti (A.a) The test methods used for each species appear below. In each case the tests were conducted under normal conditions (23"C+2"C; fluctuating light and humidity).

In each test an LCso (the dosage of active material required to kill half of the test species) for the compound was calculated from the mortality figures and compared with the corresponding LCso for a standard insecticide, ethyl parathion, in the same tests. The results are expressed as toxicity indices thus; LC50(parathion) toxicity index=~~~~~~~~~~~~~~~~~~~~~~~x 100 LC50 (test compound) and are set out in Table I below.

(i) Spodoptera Littoralis (S.l.) Solutions or suspensions of the compound were made up over a range of concentrations in 10% acetone/water containing .025% Triton X100 ("Triton" is a registered trade mark). These solutions were sprayed using a logarithmic spraying machine onto petri dishes containing a nutritious diet on which the Spodoptera littoralis larvae had been reared. When the spray deposit had dried each dish was infested with 10 2nd instar larvae. Mortality assessments were made 7 days after spraying.

(ii) Aedes aegypti (A.a.) Several solutions of the test compound of varying concentration were prepared in acetone.

100 microlitre quantities were added to 100ml of tap water, the acetone being allowed to evaporate off. 10 early 4th instar larvae were placed in the test solution; after 48 hours the (surviving) larvae were fed with animal feed pellets, and the final percentage mortality assessed when all the larvae had either pupated and emerged as adults or died.

The results are given in Table I.

Table I Insecticidal Activity

Compound of Exalrple No. | Tonicity Index 5.1. A.a.

4 1 3300 920 5 1 - 4900 490 6 1800 1600 Example 8 A caricidal Activity.

Leaf discs were infested with 30-60 larvae of the mite Tetranicus urticae and sprayed with varying dosages of solutions of the test compound made up as in test (i) of Example 10 above.

When dry, the discs were maintained at constant temperature for 12 days, after which mortality assessments were made, and the LC50 values calculated.

The results are given in table II below.

Table II Acaricidal Activity

Cwpound of | I50 ($ active ingredient Example No t in No.

4 0.0002 5 0.00035 6 0.00021

Claims

1. A compound of the general formula

in which each of A and B independently represents a halogen atom or an alkyl group; m is O or 1; each of R, and R2 independently represents an alkyl group optionally substituted by one or more moieties selected from halogen, alkoxy, alkoxycarbonyl, haloalkoxycarbonyl, alkylcarbonyl, haloalkylcarbonyl, alkylsulphonyl and haloalkylsulphonyl; X represents a halogen atom or a cyano, nitro, alkyl or haloalkyl group; each of Y and Z independently represents a halogen atom or a cyano, nitro or haloalkyl group; n is 0, 1, 2, 3 or 4; and p is 0, 1 or 2.

2. A compound as claimed in claim 1, in which each of A and B independently represents a fluorine or chlorine atom or a methyl group.

3. A compound as claimed in claim 1, in which A is a fluorine atom, m is 1 and B is a fluorine or chlorine atom in the 6-position of the phenyl ring.

4. A compound as claimed in any one of claims 1 to 3, in which X represents a fluorine or chlorine atom or a methyl group.

5. A compound as claimed in claim 4, in which X represents fluorine.

6. A compound is claimed in claim 4 or 5, wherein n is 1 and X is ortho to the nitrogen linkage.

7. A compound as claimed in any one of claims 1 to 6, in which Y represents a chlorine atom or a nitro, cyano or trifluoromethyl group, Z represents a chlorine atom or a cyano or nitro group, and p is O or 1.

8. A compound as claimed in claim 7, in which Y represents a trifluoromethyl group, p is 1 and Z represents a chlorine atom in a position ortho to the oxygen linkage.

9. A compound as claimed in any one of claims 1 to 8, in which R1 and R2 are identical.

10. A compound as claimed in any one of claims 1 to 9, in which R, and R2 are both unsubstituted alkyl groups.

11. A compound as claimed in claim 1 and named in any one of Examples 4 to 6 herein.

12. A process for the preparation of a compound as claimed in claim 1, which comprises reacting a compound of the general formula

with a compound of the general formula

in which A, B, m, X, Y, Z, R1, R2, n and p have the meanings given in claim 1.

13. A process as claimed in claim 12, substantially as hereinbefore described with reference to the Examples.

14. A compound as claimed in claim 1, wherever produced by a process as claimed in either of claims 12 or 13.

15. A pesticidal composition comprising a compound as claimed in any one of claims 1 to 11, together with a carrier.

16. A composition as claimed in claim 15, which comprises at least two carriers, at least one of which is a surface-active agent.

17. A method of combating pests at a locus, which comprises applying to the locus a compound as claimed in any one of claims 1 to 11 or a composition as claimed in either claim 15 or 16.

18. A compound of the general formula II as defined in claim 12.

19. A compound of the general formula II, as claimed in claim 18 and produced in any one of Examples 3, 5 or 6 herein.

20. A process for the preparation of a compound as claimed in claim 18 or 19, which comprises reacting a compound of the general formula

with a compound of the general formula

in which Hal represents a halogen atom.

21. A process as claimed in claim 20, substantially as hereinbefore described with reference to the Examples.

22. A compound of the general formula II, when prepared by the process as claimed in either of claims 20 or 21.