IE48749B1 - Pesticidally active benzophenone hydrazone derivatives,methods for their production and pesticidal compositions and methods - Google Patents

Abstract

Compounds of formula I in which m is 0 and n is 0 or m is 1 and n is 0 or 1; p is 0, 2 or 3, x is 0 or 1; R<1>, R<5> and R <7> are halogen, alkyl, haloalkyl, or alkoxy or R<1> and an adjacent R<5> group together with the benzene to which they are attached form a naphthyl group; R<2> and R<4> may be the same or different and are hydrogen, alkyl, acyl, an ester or thioester group, optionally substituted carbamoyl or optionally substituted thiocarbamoyl, or R<2> and R<4> together with the nitrogen to which they are attached form a 5 to 7 membered ring which may optionally contain one or more heteroatoms; R<3> is optionally substituted alkyl, alkenyl, N,N- dialkylamino, or phenyl optionally substituted by alkyl or halogen; with the proviso that when p is 0, R<2> and R<4> are not both hydrogen; have pesticidal activity, especially against insects and acarids, and pesticidal compositions and methods are described. Methods of making the compounds and novel intermediates are also described.

Description

This invention relates to compounds having pesticidal activity. Commercially available insecticidal products generally fall into four main categories, namely chlorinated compounds such as DDT, camphechlor and BHC, organophosphorus compounds such as parathion, carbamates such as carbaryl and more recently synthetic pyrethroids such as permethrin.

Resistance to an insecticide often develops after a period of use and there is therefore always a need for new insecticides and particularly for new groups of insecticides.

Many proposals appear in the literature that a group of compounds has pesticidal properties, but often such compounds are found not to be commercially acceptable as pesticides.

We have now found that certain benzophenone hydrazones have insecticidal activity against a wide range of pests.

Certain benzophenone hydrazones are already known. For instance in U.S. Patent Specification No. 3 732 307 there are described compounds of the formula Η—Ν- H N II c wherein X is selected from the group consisting of perfluoroalkyl, perfluoroalkoxy and perfluoroalkyl thio containing up to four carbonatoms, and Y is selected from the group consisting of hydrogen, chlorine, bromine, fluorine, alkyl, alkoxy, alkylthio, perfluoroalkyl, perfluoroalkoxy and perfluoroalkylthio containing up to four carbon atoms.

These compounds are distinguished in that specification from, for example, benzophenone hydrazones described by J.R. DoAmaral et al., J. Med. Chem. 12, 21 (1969) apparently by virtue of inter alia, having the hydrazine NH^ unsubsituted in the compounds of specification 3 732 307. The compounds of that specification are described primarily as plant growth regulants although it is also mentioned in U.S. Specification 3 732 307 that the compounds have activity against Insects. Of the 24 Examples given in that specification 20 of the Examples are of compounds that contain neither alkylthio nor perfluoroalkylthio groups. The emphasis throughout the specification is primarily on compounds having perfluoroalkyl, especially trifluoromethyl, substitution and there is no suggestion that the class of compounds in which there is an alkylthio or perfluoroalkylthio in the 4-position of one of the benzene rings would be of any particular utility nor that compounds which are 4-subtituted in this manner but additionally contain substituents other than those mentioned in that specification would be of any particular utility.

Certain benzylidine semicarbazides are described as insecticides in French Patent Specification No. 2 171 217.

According to the invention there are provided compounds of formula I R2- n — R4 in which m is 0 and n is 0 or m is 1 and n is 0 or 1; ρ is 0, 2 or 3, x is 0 or 1; R1, R5 and R7 are halogen, alkyl, haloalkyl or alkoxy or R1 and an adjacent R5 group together with the benzene to which they are attached form a naphthyl group; 4 R and R may be the same or different and are hydrogen, alkyl, acyl, a carboxylic ester or thioester group, substituted thiocarbamoyl, optionally substituted carbamoyl, or R2 and R4 together with the nitrogen to which they are attached form a to 7 membered ring which may optionally contain one or more heteroatoms; R3 is optionally substituted alkyl, alkenyl, N,N-dialkylamino, or phenyl optionally substituted by alkyl or halogen; and with the proviso that when p is 0 and R2 is hydrogen then R4 is not hydrogen or carbamoyl 2 4 and when p is 2 R and R are not both hydrogen. 48748 In one aspect of the invention p is 0, so that the substitution in one of the benzene rings is then SR^ and the hydrazine NH2 must be substituted. It is particularly surprising that the substitution of, for instance, R by alkyl or, especially, acyl, ester or thioester or carbamoyl gives useful compounds.

According to another aspect of the Invention p is 2 or 3. It will q of course be appreciated that by referring to the substituent -(O)2SR we mean that substituent -s'r3 H and by referring to the substituent -(0)3SR we mean the substituent - O —SRJ (I 0 The compounds where p is 3 are particularly preferred in the invention. It will further be appreciated that these substituents are entirely different from any substituents suggested in U.S. Patent Specification No. 3 732 307.

In the present specification any reference to halo or halogen should be construed as a reference to fluorine, chlorine, bromine or iodine, preferably fluorine, chlorine or bromine.

Preferred compounds within the first aspect of the invention include 1 2 those wherein p, n, x = 0, m = 1, R is halo, R is hydrogen, o 4 R is alkyl and R is acyl or alkoxycarbonyl.

Preferred compounds within the second aspect of the invention 2 15 include those wherein p = 3, x = 0, R is hydrogen, R and R are halo R4 is hydrogen, acyl or alkoxycarbonyl and R2 is alkyl, optionally substituted phenyl or optionally substituted benzyl.

In formula I, r\ R8 and R2 are preferably halogen and especially chlorine. When one of these groups is alkyl or alkoxy these may be e.g. of 1 to 4 carbon atoms, but are preferably methyl or methoxy. It is generally preferred that m is 1, and n and x are 0. When they are haloalkyl this is preferably, trifluoromethyl. ? 4 R is preferably hydrogen and R is preferably other than hydrogen and is usually a carbonyl derivative. When RZ and R4 are alkyl this may be e.g. of 1 to 4 carbon atoms, and is preferably methyl. If R2 or R4 form a ring with the nitrogen to which they are attached this may be for example piperidine, pyrrolidine, thiamorpholine and especially morpholine.

If R or R is an ester or thioester group this is generally of © formula R XCO, where X is oxygen or sulphur, preferably oxygen and R8 is an organic radical e.g. alkyl, e.g. of 1 to 12, preferably 1 to 8 carbon atoms, and especially ethyl, these alkyl groups being optionally substituted, (e.g. by Cp^alkoxy; C3_y cycloalkyl, halogen or aryl, such as phenyl, substituted phenyl or naphthyl, aryloxy such as phenoxy and substitutrd phenoxy); cycloalkyl, e.g. of 3 to 7 carbon atoms and especially alkenyl e.g. of 2 to 12 carbon atoms, 48748 which group may optionally be substituted (e.g. by aryl such as phenyl or substituted phenyl); alkynyl e.g. of 2 to 6 carbon atoms, aryl such as optionally substituted phenyl or 2-naphthyl; heteroaryl, such as furyl, thienyl, pyridyl; and heterocyclyl such as morpholinyl, piperidyl and thiamorpholinyl. Where a phenyl group is substituted this may be by a wide number of groups e.g. alkyl, haloalkyl, nitro, alkoxy, alkylthio, dialkylamino, phenyl or halogen. If R2 or are acyl this is generally of formula R9CO 9 8 where R is R as defined above or hydrogen.

If R2 or R4, in Formula I, is an optionally substituted carbamoyl group or a substituted thiocarbamoyl group, the group may be of the formula -CXNR^R^1 where R10 and R11 are the same or different and are hydrogen, optionally substituted alkyl or optionally substituted phenyl or together with the nitrogen to which they are attached form a 5 or 7 membered ring which may optionally contain one or more heteroatoms and X is 0 or S, except that when X is S R^ and R^1 cannot both be hydrogen. Suitable optionally substituted alkyl or phenyl or heterocyclic 2 4 8 groups are listed above in the description of, for instance, R , R and R . R3 is preferably optionally substituted alkyl, e.g. of 1 to 4 carbon atoms. Preferred substituents are halogen. When R is alkenyl this is usually 1-propenyl. When R3 is dialkylamino this is preferably dimethylamino. It is particularly preferred that R is methyl or trifluoromethyl.

A preferred group of compounds are those in which p is 3.

A particularly preferred group of compounds are those in which m is 1, n and x are 0, p is 3, R is halogen, R is alkyl, optionally substituted by halogen and R2 is hydrogen. 487 49 Especially preferred from this group are compounds in which 3 4 8 R is methyl or tri fluoromethyl and R is R (0) CO where q is 0 or 1, M o R is C1-12 alkyl, optionally substituted by alkoxy, C3_7 cycloalkyl, halogen phenoxy or substituted phenoxy; C3_? cycloalkyl, θ2-12 alkeni^’ optionally substituted by phenyl or substituted phenyl; C2_g alkynyl, or optionally substituted phenyl, wherein any substituted phenyl group is substituted by C^_4 alkyl, C-|_4 haloalkyl, nitro, C-|_4 alkoxy, ΙΟ alkylthio, C, . di alkyl amino, phenyl or halogen; and when 1-4 8 q is 0, R is also hydrogen.

The compounds of the invention are active against a variety of economically important insects that cause serious and widespread damage to crops which as, for example, insects of the order Lepidophera including caterpillars of the diamond back moth (Plutella maculipennis), the cabbage white butterfly (Pieris brassicae), the Epyptian cotton leaf worm (Spodoptera littoral is) and Heliothis spp. such as H. armigera H. viriscens and H. zea. Many of the compounds have also shown activity against other caterpillars such as these of the codling moth (Laspeyresia pomonella). Some of the compounds have shown activity against other pests such as beetles of the order Coleoptera, including the mustard beetle (Pheadon cochleariae), grain weevil (Sitophilus granarius), flour beetle (Tribolium castaneum) and meal worm (Tenebrio molitor); cockroaches of the order Orthoptera such as BIatelia germanica; aphids of the order Hemiptera, including the vetch aphid (Megoura viciae).

Many of the compounds also have activity against a variety of economically important acarid and insect pests of animals, including farm livestock. For example, many compounds have been shown to be active against larvae stages of insects of the order Diptera e.g. sheet blowfly 48748 (Lucilia spp.) and mosquitoes e.g. Aedes aegypti. Some of the compounds especially those in which R^ is optionally substituted carbamoyl or substituted thiocarbamoyl group have shown systemic activity, i.e. the internal tissues of an animal which has been treated with tiie compound exert an insecticidal effect. This property is important in the treatment of animals such as cattle, which are infested with tissue-dwelling stages of insects e.g. warble fly (Hypoderma spp.). Some of the compounds are also active against lice and keds and acarid parasites especially ticks e.g Boophilus microplus and mites e.g. Sacoptes spp.

Some of the compounds have also been shown to have fungicidal, herbicidal and plant-growth regulant activity.

The invention also includes an insecticidal composition comprising a compound of formula I and an inert diluent. More than one compound of the invention can be included in the composition, and the diluent can be a solid or liquid, optionally together with a surface-active agent for example a dispersing agent, emulsifying agent or wetting agent.

One or more additional pesticides such as for example compounds known to possess acaridical or insecticidal activity can be added to the composition of the invention to enhance or widen the spectrum of its activity.

Such additional pesticides include, for example, an organophosphorus compound such as tetrachlorvinphos, fenithrothion, demeton-S-methyl, phosalone, dioxathion, chlorfenvinphos, dichlorvos, bromophosethyl, diazinon, dimethoate, methyl parathion, Bolstar[o-ethyl-0-(4methy1thiophenyl)-S-propy1 phosphorodithioate], or chlorpyrifos; a carbamate such as methomyl, carbaryl; pirimicarb or promecarb; a bridged diphenyl compound such as tetradifon, tetrasul or DDT; a chlorinated 487 49 hydrocarbon such as benzene hexachloride, endosulphan, endrin or toxaphene; an acaricide such as amitraz, chlordimeform, clenpyrin, chlormethiuron or nimidane; a synthetic pyrethroid such as permethrin, fenvalerate or cypermethrin or a thin pesticide such as cyhexatin or fenbutatin oxide.

The composition of the invention can take any of the forms known for the formulation of insecticidal compounds, for example, it can be in the form of a solution, an aqueous dispersion, an aqueous emulsion, an emulsifiable concentrate, a dispersible powder, a dusting powder or granules. Thus it can be in a suitable form for direct application as an insecticide or as a concentrate requiring dilution with an appropriate quantity of water or other diluent before application.

As a dispersion the composition comprises a compound of the invention dispersed in an aqueous medium. It is often convenient to supply the consumer with a concentrate which when diluted with water forms a dispersion of the desired concentration and can be.provided in, for example, any of the following forms. It can be a dispersible solution which comprises a compound of the invention dissolved in a watermiscible solvent with the addition of a dispersing agent, or a dispersible powder comprising a compound of the invention and a dispersing agent. A further alternative comprises a compound of the invention in the form of a finely ground powder in association with a dispersing agent and intimately mixed with water to give a paste or cream which can if desired be added to an emulsion of oil in water to give a dispersion of active ingredient in an aqueous oil emulsion.

An emulsion comprises a compound of the invention dissolved in a water-immiscible solvent which is formed into an emulsion with water in the presence of an emulsifying agent. An emulsion of the desired concentration can be formed from a concentrated stock emulsion that comprises a compound of the invention in combination with an emulsifying agent, water and water-immiscible solvent. Alternatively the consumer can be supplied with an emulsifiable concentrate comprising a solution of a compound of the invention in a water-immiscible solvent containing an emulsifying agent.

A dusting powder comprises a compound of the invention intimately mixed and ground with a solid pulverulent diluent, for example, kaolin.

A granular solid comprises a compound of the invention associated with similar diluents to those employed in dusting powders but the mixture is granulated by known methods. Alternatively the active ingredient can be absorbed or adsorbed on a pre-formed granular diluent for example fuller's earth, attapulgite or limestone grit.

The concentration of the active ingredient (when used as the sole active component) in a composition for direct application to the crop by conventional ground methods is preferably within the range of 0.001 to 10 percent by weight of the composition, especially 0.005 to 5 per cent by weight, but more concentrated compositions containing up to 20 percent may be desirable in the case of aerial sprays. As a concentrated primary composition the concentration of active ingredients nay vary widely and can be, for example, from 5 to 95 percent by weight of the composition.

As previously described the compounds of the invention have exceptional activity as insecticides and accordingly the invention includes a method of combating insects which comprises applying a compound of formula I to the locus of the insects, that is, the insects or their habitat. The compound of the invention can either be applied on its own or more preferably as one of the compositions described above.

Many of the insects which the compounds of the invention are active against, for example those of the order Lepidoptera and Diptera, attack plant life and a preferred method of the invention is one of protecting plants from attack by insects by applying a compound of formula I to the locus of the plants. For instance the diamond back moth and cabbage white butterfly attack vegetable crops such as brassicas, and leaf worms are a serious pest on cotton.

Direct treatment by for example spraying or dusting the plants infested with insects is often the preferred method but the active compound can also be applied to the soil in which plants are grown as granules, or as a root drench. In such instances the active compound is absorbed by the roots of the plant and confers protection from the insects. The quantity of active compound applied can vary widely depending on the particular circumstances and usually the amount is in the range of from 0.01 to 20 kilograms per hectare, more especially, from 0.1 to 10 kilograms per hectare.

Also included in the invention is a method of protecting animals from attack by pests which comprises treating the animal with a compound of formula I. Parasites are a frequent source of irritation to animals such as livestock and many can be controlled by external application of a compound of formula I. The method may be by direct application to the animal, or by application to the quarters, e.g. buildings, in which the animals live.

The compounds of the invention can be prepared by a number of processes, as follows: 1) By reacting a compound of formula II the product can then be acylated with a) an acyl halide or acid anhydride when R2 or R4 is to be an acyl group, with b) a chloroformate or 2 4 chlorothioformate when R or R is to be an ester group, or with c) an isocyanate or isothiocyanate when R2 or R4 is to be an optionally substituted carbamoyl or a substituted thiocarbamoyl group.

In this specification it will be appreciated that the term acylating agent includes these three types of compound.

The reaction with the hydrazine or hydrazine derivative is usually carried out at a temperature of from 50°C to 100°C, in the presence of acetic acid.

The acylation reaction is preferably carried out in the presence of an inert organic liquid as the reaction medium which is also preferably a solvent for the reactants, at a temperature of from 0°C to 100°C. Advantageously the reaction is effected in the presence of a suitable acidbinding agent, for example a tertiary alkyl amine, pyridine or an alkali metal carbonate. When the acylating agent is a halide this is preferably the chlorine.

Compound of formula II in which p is 3 can be prepared by reacting a sulphonyl halide of the formula R3S0gX where X is halogen and preferably chlorine, with the corresponding 4*-hydroxy compound of formula III This step is preferably carried out in the presence of an inert organic solvent and an acid binding agent.

Compounds of formula II in which p is 0 can be preapred by a 5 Friedel-Craft reaction between where Y is a halide, usually chloride, with Compounds of formula II in which p is 2 may be prepared by oxidising e.g. 10 with hydrogen peroxide, the corresponding compound in which p is 0. 2) when p is 3, by reacting a compound of formula IV R2 R4 \ / N 4 in which R and R are not both, hydrogen, with a compound of formula 3 R S02Y in which Y is halogen, preferably chlorine. The reaction is preferably carried out at a temperature of 0 to 100°C, usually in the presence of an acid binder.

Compounds of formula IV can, in their turn, be prepared by reacting a suitable hydrazine derivative of the formula NH2NR2R4 with a compound of formula III above, preferably in the presence of an inert organic solvent and optionally together with acetic acid.

The present state of our knowledge indicates that most of the above reactions give rise to a product that comprises a mixture of the E and Z-isomers.

It is to be understood that formula I above denoting the compounds of the invention includes both these isomers. In all cases the pairs of isomers can be separated by conventional methods, such as for example chromatography or fractional recrystallisation, but, as the isomeric mixtures have very valuable insecticidal activity, we generally find that there is no advantage in separating the isomers. The activity of the isomers of any one compound may differ and in some cases the activity of one isomer may be negligible; pure isomers lacking insecticidal activity form no part of the present invention. The novel reactants of formula IV also exist in isomeric form and the structure shown is intended to include both of the isomers.

The invention is illustrated in the following Examples.

Compounds according to the invention were prepared according to one of the following reaction schemes.

SCHEME 1 nh2nr2r4 in which at least one of RZ and R is not H (R1) OSOgR3 n2h4 OSO,RJ SCHEME 3 acylating agent SCHEME 4 c° “@7 (R5)n (A) from/ nh2nr2r4 I r3so2ci SCHEME 5 48748 SCHEME 6 (R1) oxidise nh2nh2 Acylating, agent (I) from Scheme 5 nh2nr2r4 By the term acrylating agent is included acid halides, acid anhydrides, and isocyanates. Examples 1 to 6 are typical examples of preparations according to these schemes.

Structures of all compounds prepared according to the invention were 5 confirmed by infra-red analyses.

Example 1 Illustration of Scheme 1 Phenol is reacted with £-chlorobenzoyl chloride in a Friedel-Crafts reaction in the presence of aluminium chloride to give 4-chloro-4'-hydroxybenzophenone, 179-181°C (A). To a solution of this (5 g.) in pyridine (6 ml.) was added methanesulphony! chloride (2.5 g.), at room temperature. The reactants were heated on a steam bath for 1J hours and the liquid reaction product poured into dilute hydrochloric acid to give a solid which was filtered and air-dried. This solid was recrystallised from industrial methylated spirits to give 4-chloro-4'methylsulphonyloxybenzophenone, m.p. 120-121°C. (ΒΙΑ solution of 9.4 g of this product and ethyl carbazate (7.8 g.) in glacial acetic acid (8 ml.) and ethanol (200 ml.) was heated under reflux for 48 hours and then evaporated to dryness in vacuo. The residue was extracted with methylene chloride (250 ml.) and the extract washed with water, aqueous sodium hydroxide (2.5 N) and water and then dried and evaporated to dryness to give 4-chloro-4‘-methylsulphonyloxybenzophenone ethoxycarbonyl hydrazone, m.p. 132.5 - 140°C (C).

Example 2 Illustration of Scheme 2 To a solution of (8) from Example 1 (9.35 g.) in ethanol (200 ml.) was added hydrazine hydrate (8 ml.) followed by glacial acetic acid (1.5 ml.). The mixture was heated under reflux with stirring for 17 hours. The solvent was evaporated under reduced pressure to give an oil which was extracted with chloroform. The extract was washed with water, aqueous sodium hydroxide and water and then dried over magnesium sulphate. The solvent was evaporated under reduced pressure to give an oil. On standing this crystallised to give 4-chloro-4'-methylsulphony1oxybenzophenone hydrazone, m.p. 70-110°C (D).

Example 3 Illustration of Scheme 3 A solution of propionyl chloride (2 g.) in ether (15 ml.) was added dropwise with stirring to a solution of (0) from Example 2 (6.2 g.) in pyridine (20 ml.) at 0 to 5°C over 30 minutes. The mixture was then stirred at room temperature for 1J hours and then quenched with water (1 litre) and the solid filtered, washed with dilute hydrochloric acid and water and dried in vacuo at 60°C for hours to give 4-chloro-4‘-methylsulphonyloxybenzophenone propionylhydrazone m.p. 128 to I44°C (C).

Example 4 Illustration of Scheme 4 A solution of A from Example 1 (92.8 g.), ethyl carbazate (100 g.) glacial acetic acid (100 ml.) in ethanol (1 litre) was heated under reflux, with stirring, for 48 hours. Evaporation of solvent under reduced pressure gave a slurry and the solid was separated from the liquors by filtration. This solid was washed with a little cold industrial methylated spirits and then dried in vacuo at 50°C.

The liquors were evaporated again under reduced pressure and the resulting oil was extracted with chloroform and the extract washed with aqueous sodium carbonate and then water. The extract was dried over magnesium sulphate and evaporated under reduced pressure to give a second batch of solid.

The combined solid material was recrystallised from industrial methylated spirits to give 4-chloro-4'-hydroxybenzophenone ethoxycarbonyl hydrazone, m.p. 185-187°C. (E). To a solution comprising (E) (95.55 g.) and triethylamine (90 ml.) in tetrahydrofuran (700 ml.) was added dropwise methanesulphonyl chloride (44.7 g.) in tetrahydrofuran (25 ml.) over 35 minutes. A fine precipitate formed with evolution of heat and the mixture was left overnight with continuous stirring. It was poured into water (500 ml.) and then extracted with methylene dichloride (500 ml.). The extract was washed with five 500 ml. portions of water and then dried with magnesium sulphate. Evaporation of solvent under reduced pressure gave a semi-solid residue which was triturated with industrial methylated spirits, filtered and washed with further solvent, leaving a white solid which was dried in vacuo at 75°C for three hours, to give 4-chloro-4‘methylsulphonyloxybenzophenone ethoxycarbonyl hydrazone, m.p. 132-142°C. (C).

Example 5 Illustration of Scheme 5 Isopropyl phenyl sulphide was reacted with 4-chlorobenzoyl chloride in a Friedel-Crafts reaction in the presence of aluminium chloride to 4874a give 4-chloro-4‘-isopropylthiobenzophenone, m.p. 105-107°C. (F). To a solution of (F) (101 g.) in ethanol (650 ml.) was added hydrazine hydrate (67.5 ml.). The mixture was heated under reflux for 24 hours, after which the solvent was evaporated under reduced pressure. Water was added to the residue which was extracted with chloroform, washed with aqueous sodium hydroxide and then water. The organic extract was dried with magnesium sulphate and evaporated under reduced pressure to give 4-chloro-4'-isopropylthiobenzophenone hydrazone, b.p. 188-190°C at 0.1 mm. (G). This was then treated in a similar manner to that described in Example 3 with ethyl chloroformate to give 4-chloro-4‘isopropylthiobenzophenone ethoxycarbonyl hydrazone, m.p. 115-135°C. (H).

Example 6 Illustration of Scheme 6 Using a Friedel-Crafts reaction as described in Example 5 there was obtained 4-chloro-4‘-propylthiobenzophenone, m.p. 94-95°C. (F).

This (2.9 g.) was then dissolved in glacial acetic acid and hydrogen peroxide added (3.5 ml of 100 vol.). The mixture was stirred and heated at 60°C for 5 hours and then poured into water. The solid product was collected washed with water, dried and then poured into water, dried and recrystallised from ethanol to give 4-chloro-4'propylsulphonyl benzophenone, m.p. 140.5-142.5°C. (I). This was then treated with hydrazine hydrate as described in Example 5 to give 4-chloro4'-propyl sulphonyl benzophenone hydrazone, m.p. 110-120°C. (J), which was then treated with propionyl chloride in a similar manner to that described in Example 3 to give 4-chloro-4'-propyl sulphonyl benzophenone propionyl hydrazone, m.p. 155-170°C. (K).

Example 7 Illustration of Scheme 7 A solution of (F) from Example 5 (14.52 g) was treated with ethyl carbazate in a similar manner to that described in Example 1 to give 4-chloro-4-isopropylthiobenzophenone ethoxycarbonyl hydrazone, m.p. 155-135 °C.

In the above and with the following Examples the products are generally obtained as mixtures of geometric isomers, the ratio of the two isomers varying from product to product.

Examples 8-22 The compounds shown in the following Table were prepared by one of the schemes given above in a similar manner to the method described above in the appropriate Example; The physical data (melting point in °C, unless otherwise stated) are given in column J for the final product, in column K for the starting material and in column L for the intermediate.

When using Scheme 3 the starting material is the product of a previous Example.

The starting material (column K) is type A when Schemes 1, 2 or 4 20 are used and type F if Schemes 5 or 7 are used.

The intermediate (column L) is type B if Scheme 1 or 2 is. used, type E if Scheme 4 is used and Type G if Scheme 5 is used.

In the column headed A there is given the type of acylating agent or hydrazine derivative used as follows: Acylating Agents M N Ν' 0 P Q MM NN Hydrazine derivatives S T U V W X Y Acyl halide Acid anhydride Acetic-formic anhydride Methyl isocyanate Phenyl isocyanate Methyl isothiocyanate p-Chlorophenyl isocyanate Ethyl isocyanate Ethyl carbazate Methyl carbazate Semicarbazide Benzyl carbazate N-aminomorpholine Thiosemicarbazide 4,4-Dimethylsemi carbazi de The column headed B identifies the scheme used.

The column headed C identifies the Example from which the starting material is derived.

In the Table ND = not determined * = Starting material prepared by reacting product of Example 2 with methyl hydrazine to give crude 4-chloro-4-methylsulphony oxybenzophenone methyl hydrazone.

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CC X I X X X X X X X δ X Φ 2 X X X X Q. a cn cn cn cn cn cn A A cn A cn cn cn cn A J? A o φ 0) φ 3 φ Φ o o Φ φ f © o » CC S 0. 2 2 2 ID 2 2 2 2 2 2 o 2 5 i δ to tz I I X X X X X X X X X X X X X I m X X X X X X X X X ϋ X X X X X χ. X X o o υ o Ο o O Q o o ID o υ u o o χ 6 2 A o CM A b- co A ο CM A LU Z cn tr tr V tr tr tr »r *r tn m tn in TABLE 1 (Continued) o CO M· CO xb CO e CM CM CM CM CM CM CM CM ω CO CO m- - co - co CO - - CO <0 CO CO ¢0 CO < 2 2 cn CO 2 CO 2 O □ 2 s 2 2 2 2 co -203 CM O> m 0» in 8 o Oi j 200.5- 89.5- X co ΐ co GO 135-1; 185-1 X. 187.5^-191 193-194 191-192 s I co 187.5—191 179-181 I S’ZSI «e -e 130.5 a o β CO <0 r- co GO N. V -103 s co 146 ·* r K a CM CO o co ~3 I s 1 o V 129.5- -εβι I r* b- i 0· CO 130- I co co T· I CM a CM I s 1 co 139- i m ® 150- 157- c CC I —COPr - CQBu -COOEt -COOEt V o Q I -COOEt £ Φ 2 O O o Φ 8 -COOEt CM § o o -COOBu φ 2 X o CM $ 8 I -co-f^ Cl CM U 5 8 b- o 8 o i -coo— -COOEt CM CC I X X X X X X X X X X X X X X X X fe X X X X X X X X X X X X X X X X X a co co co co co co co co co CO co co co CO co «0 co CJ CC © 2 Φ 2 CM 5 Φ 2 Φ 2 φ 2 « 2 « 2 « 2 Φ 2 Me Φ 2 Φ 2 Me Φ 2 Φ 2 o o ft X X X X X X X X X X I I I I X X X tfj a: X X X 5 X - I X I X I X X X X X X T~ cc m ffl m δ m δ δ δ LU m δ δ δ δ δ δ δ x o' U1 Z S tn in 8 N. to 8 <5 tn 8 τ— co CM CO CO co V co to co £ b» CO ¢0 CO σ> co g UJ CD < υ CM CM CM CM CM CM CM CM CM CM CM CM CD rt rt rt - - rt « co rt CO - « rt O rt < 2 2 2 co □ 2 2 2 s s <0 2 2 2 2 125-127 120-121 136-137 167-168 179-181 e in co in -? 180-186 166-169 182-186 I 184-188 a> 7 •e •m· 158-174 89-97 166-168 128-129.5 156-158 150-165 94-122 115-132 105-127 102-132 u. φ 2 δ Φ 2 ow z T CC Φ o o 1 8 I Φ o ϋ 1 ί -COOEt CM X z o o φ ο ο I in X Qf 8 I ft o s o 1 -CO#^ -COOEt UJ 3 o m o o o o ( I -COOBul 8 X o o o ί CM CC X X X X X X I X X X I I I X X N- CC X X X X X X X X X X X X I X X o. rt rt rt rt rt rt rt « rt rt rt rt co rt rt CO CC φ 2 Φ 2 φ 2 Φ 2 Φ 2 (0 2 o 2 o 2 o 2 © 2 φ 2 rt LL © O 2 © 2 © 2 E X X X X X X X X X X X X X X X tn X X X I δ X X X X X X δ X X X X X o δ Q ® 2 O o δ δ 5 5 δ o 2 δ δ δ δ x 6 ω z h- CM r*. rt h- 'T h» in h- (0 r* co h- a> r«- o 00 oo CM co co co co in co TABLE 1 (Continued) o r-i CM CM * CM CM CM CM CM CM ffl Cj CO CO co CO 'i CO <0 CM CO <0 co < V) 2 2 2 2 2 co 2 2 co 2 2 2 37.5 1 o σ» 8 8 -] 1 7 i '» to IO Oi m ifl co IO ε to 8 5 id 7 f O> Oi b- ** co io V M· V) b- 8 IO * to b. b. <0 b. o 8 co s CO b. o b. 8 i 8 I S 1 CO Λ 7 1 T· I 1 to δ j, 1 I b- Λ b. < m o to co b- co IO ® δ δ 2 5 «An Z\ £ Q. π ι ΓΪ I li < > o co in γ CM T J UJ V V UJ Q T 1 o 0. Q o 1 1 O IL O o 1 -co -co o o t -co 1 o o 1 8 1 -co X o o 1 8 1 1 8 1 CM (C X X X X 2 X X I X X X X X X ΐε u. X X X X X X X X X I X X X Q. co co co co n co <0 co co <0 CO co co co «. ® ® o ® « ® o ® ® CM « ® 9 ® (£ 2 2 2 2 2 CL 2 2 2 2 2 2 2 έ ·& X X X I I X X X X o X X X X 'a: X X X X X X X X X X X X X X £ o δ ϋ o o o Q o o Q o □ Q δ x 6 uiz 8 N. CO s o> «0 8 σ» CM 0) <2 Oi * O) in 01 8 a 8 8 Ο CM CM CM CM CM CM CM CM CM CM CM CM CM ω CO τΤ CO CO co co co co CO co co CO co - CO < 2 « 2 2 s 2 2 2 2 2 2 2 2 co 2 ο σ> CD 1 7 ο Oi co co in hr 7 7 r- s in in co ’ί £ £ ό S) CM § o co Tf 8 “5 '! Ί 1 7 Ί Ί 1 I 7 7 Λ 7 7 1 1 CM CO Ο CM co co co co m· N. CO r- to co co co CM δ Tf CC tn ro E I o u X o co cm X tn CM X CM o' CM X o π X o CM X o Φ 2 Φ £ to « I UJ Φ 0 IX CM to UJ 9 CM X o o o o Q O 1 1 -CO(C o o 1 o o O X o o 1 1 o o o o 8 1 M — CO -co· -co. Bi -co- -co- o o o 1 -coc CM α: X X I X X X X X X X X X X X X κ X X X X X X X X X X X X X X X X Ο. co co co co co CO co co CO co co co co rt co CM o 2 Έ 2 O 2 2 2 2 2 2 5 2 2 2 2 2 X (Ο CC X X X I X X X X X X X X X X X ίθ X X X X X X X I X X X X X X o 2 X ’χ ο δ δ δ δ δ δ δ δ δ δ δ δ δ δ χ ο Ο V- CM co ττ «η n. CO o o CM CO Tf ω ζ Ο Ο O o ο ο o o t* o o *- T“ TABLE 1 (Continued) o (u CM CM CM CM CM CM CM CM CM CM CM CM CD co CO CO CO co 5»· CO CO CO co CO CO CO CO < 2 2 2 2 2 OT OT 2 2 2 2 2 2 2 2 8 8 -I 1 in GO T“ CO co y: N. T*· 6- in T“ 197 0> V 8 rs. CO r- CM 5T <0 8 in in 8 co to 8 5 V- & T“ 7 -> I h. CO Λ 133- r- co 1 CM 1 1 co 4 1 GO 1 Ό· d 0» Xf a fs. CM © CM in V 10 0 r- O $ JL U.” o (D £ Z Q. β ! 2 nf / \uj \\ /)% h. IL , $ ά UJ UL tt -co- O o o oJ o o f -co- -coot -coot -coot 5 0 υ I 1 -coo -co- 0 8 1 δ o 1 -co- 1 CM X x r X X X X X X X X X X X X X 'i X X I X X X X X X X X X X X X CL co co co co «0 co co co co w CO CO co co co co φ o Φ Φ Φ 3 Φ Φ Φ φ φ φ φ 0 X 2 2 2 2 2 UJ £0 2 2 2 2 2 2 2 2 to X X X X X X X X X X X X X X I X tn X I X X X 9 2 X X X X X X X X X X Vc δ δ δ δ Φ 2 δ δ O 0 0 0 0 Q δ 0 x o w to N β 0» a CM CM 8 8 8 £m 8 8 u) Z - T- β 4874S TABLE 1 (Continued) 0 m N © m- o- © © p- © © © © © © © © © © © < CO z co co 2 2 CO 2 2 z 2 2 2 2 2 2 2 2 d d d © © d ©_Cf) co © « © rt © § rt © rt © o © 8 8 © © 8 -1 3 1 1 © © o o J. J. J. 8 J. ( © I © 1 © ] © 1 © © © 0 © © © © © © © r· © © d d d d d d X) © © © Xi p- o © 8 © 8 8 © © © © © © •fc. © © © © © o © 8 o © o o o 'l © o ( 1 © © © © 8 7 © 7 7 XT 1 co 7 1 © « 1 « 7 W rt i- V* +“ © a r- © 1- *- d X) a o 133 127 108 rt CM 120 § 145 © CM 102 CM rt 4— rt 103 120 120 -o 7 { g 1 ( o co 1 © 1 © A rt 1 © CM 5 I P- © J © J s I o rt ιr· © o © T- rt © © CM © <0δ« f5 JL 0 CM J. o i f^n X X - ‘ά 0 CM X* 3UCM ω © UJ UJ UJ X T “L 3 3 © X X X n δ 8 g (U X O o u O X m ω Ω 0 0 1 0 o o o o o Q T Ω o o o o o p o o o 1 ο 0 1 1 o 0 1 o I 0 o o 1 0 1 □ o I 0 0 0 1 o 1 0 I cm X X X X X X X X X X X X X X X X X X X Ί X X X X X X X X X X X X X X X X X X Q. © © rt rt o o o o O o o o © σ © o © © « X X X X UJ X <Λ 3 CQ ® 2 u X X X X X X X X X ’“L. X X © X X 3 X X X X X X X X X X X X I I X X m X X X X X X X X X X X X X X X X X I X C m o 3 3 m 5 3 3 3 3 3 3 3 3 0 3 3 0 x o S? h- ΑΓ 8 © © © rt © s © © 8 P- © 8 © © § r“ © CM © rt © UJ z V Τ» UJ .j CD < o CD fs. r- in in in in in m tn in in in in in m m rt rt < rt 1- 5 2 Z 2 Z Z 2 Z 2 s 5 2 2 2 2 2 V“ ,. τ- Q a o o co o d o o o o d --. ««» *S. co CO r> o o rt rt rt co co co rt o o © o o o rt rt cn cn cn rt rt ο rt rt rt rt 1 o co o cn co cn rt 1 1 co co rt co co co co rt co co co rt co rt co co co co UJ *“ a CD t” CL Q. d. ci, ci. d. Q. d. Q. ¢3, fi. d. JO Δ jO jO n JO -Ω Λ X3 Δ- J3 rt in tn tn CO cn in cn in rt rt in rt O tn in co o o o o o © in cn © o © o o o 0) rt co cn σ> 1 L I 1 1 1 1 1 J 1 1 t 1 1 co XT •Μ- co co CO rt co rt tT co CO co co co co o 0) rt CD o o o o rt o rt rt o o © o o o T“ m T CO © in σ» N- rt CM h*. o h. co co CM co CO ’J CM tt co cn CM V T T— CM CM- ’t I rt r •o 1 tn 8 rt 1 m 1 cn CM co 1 cn 1 r- ί tn 1 r- 1 o CM 1 rt 8 1 co i T“ 1 o »- CO co tr V co T co rt CO rt CM co 0 Φ 2 0 M· X jc G_ rl o CO ή O CM LJJ LJJ 1 x UsJj UJ 2 T cn 73 co /17 co 1 a () X n UJ 0 2 n m O n 0 1 71 J O o O O O O o O r> n T Q o o O πu R O o o 1 U O 1 o 1 (J 1 o o o I o 1 a 1 0 1 0 1 0 1 O 1 o 1 o 1 0 1 I CM CC X X I X X X X X X X X X X X X I .X X r— CC I X X X X X X X I X X X X X X X X X CL o o o © o © o o o o o o © © o © o a co a: £ £ £ “φ (D £ £ £ £ £ £ £ £ £ £ £ £ £ £ co X X X I I X X X X X X X X X X X X X X in X X X X X I X X X X X X X X X X X X X Έ 5 ΰ ΰ o o ΰ 5 δ δ δ 0 0 0 0 0 0 0 0 Ό· in r-. rt cn o CM co cn rt r- rt rt o (O cn (0 cn cn co f- r*. n- N. r*. r— r- r-,. co rt u z TABLE 1 (Continued) tr 487 49 TABLE » (Conlinuod) Ο CM CM CM m A A A - - < X 1 Z z A A u 3 A A b- b- “5 I I ao H s. S3 in δ c £ Ml X UJ X s UJ 8 UJ 8 o 1 a l a I o 0 CM c X X X « 2 X b* c X X X X X a A A A A A A a> « Φ u? ® X 2 5 2 o 2 <0 X I X X I X to X X I I I I lT if? X υ o o 0 0 •Μ- A to b. eo UJ z A a A A A 48743 Example 219 The product of Example 4 was separated into its geometric isomers by high pressure liquid phase chromatography. TheE isomer had a m.p. of T60-T61°C and the Z-isomer had a m.p. of 152-156°C.

Example 22Q This Example illustrates the activity of compounds of the invention against larvae of the diamond back moth (Plutella maculipennisj.

Ten larvae were placed in a tube together with a square inch of cabbage which had been dipped in the test solution and allowed to dry.

After twenty-four hours untreated cabbage was added for food and after a further twenty-four hours an assessment was made of the mortality of the larvae.

Two replicates were carried out for each test compound and test solutions of varying concentrations employed so that an LDg0 value could be calculated.

The compounds of Examples 1 to 218 had an LDgg of less than 5000 ppm.

Example 221 The following types of concentrates were formulated as below: later Dispersible Concentrate Product of Example 4 15.0% w/v Ethyl an BV1 15.0% w/v Ethyl an C40 AH2 15.0% w/v Cyclohexanone 30.0% W/v N-Methylpyrrolidone 31.0% w/v Aqueous Flowable Product of Example 4 33.0% w/v Dyapol PT3 5.0% w/v A Monolan PB 0.25% w/v Anti foam M309 0.5% w/v Rhodopol 2% gel 0.1% w/v Water to 100% vol. Oily Suspension Product of Example 4 33.0% w/v Dyapol PT3 1.0% w/v Ethylan ENTX4 * * 7 15.0% w/v Antimousse 4118 0.5% w/v Light Liquid Paraffin to 100.0% vol. Dispersible Powder Product of Example 4 50.0% w/v Dyapol PT3 10.0% w/v Aerosol OT-B9 0.5% w/v Precipitated silica 10.0% w/v Polyviol Ml 3/14010 2.0% w/v Kaolin 27.5% w/v Ethylan, Monolan, Rhodopol and Polyviol are Trade Marks A nonyl phenolethoxy!ate, ? AH is an ethoxylated castor oil. 3 Sodium salt is a cresol sulphonic acid/formaldehyde condensation product. 4 Ethylene oxide/propylene oxide copolymer, c A silica based emulsion.

A high molecular weight polysaccharide. 7 Alkyl phenol ethoxyl ate.

Q A silica based emulsion 9 Dioctyl ester of sodium sulphosuccinic acid.

A grade of polyvinyl alcohol.

Claims (22)

1. Compounds of fonnula I in which m is 0 and n is Oy^tn is 1 and n is 0 or 1; p is 0, 2 or 3, 15 7 5 x is 0 or 1; R , R and R are halogen, alkyl, haloalkyl, or alkoxy or r! and an adjacent R 5 group together with the benzene to which they are attached form a naphthyl group; R and R may be the same or different and are hydrogen, alkyl, acyl, a carboxylic ester or thioester group, substituted thiocarbamoyl or optionally substituted carbamoyl or 2 4 10 R and R together with the nitrogen to which they are attached form a 5 to 7 membered ring which may optionally contain one or more heteroatoms; R is optionally substituted alkyl, alkenyl, Ν,Ν-dialkylamino, or phenyl optionally substituted by alkyl or halogen; with the proviso that when p is 0 and R is hydrogen then R is not hydrogen or carbamoyl 2 4 15 and when p is 2 R and R are not both hydrogen.

2. Compounds according to claim 1 in which the ester or thioester o group is of fonnula R XCO- where X is oxygen or sulphur and R is optionally substituted alkyl, optionally substituted alkenyl, g cycloalkyl, aryl or heteroaryl, the acyl group is of formula R CO where 20 R 8 * is hydrogen or R 8 , and the carbamoyl group is of formula -CONR^V^ where R 10 and R 11 are the same or different and are hydrogen, optionally Suhs&fcufced aiKjL o' ocb'onallij 48748 substituted phenyl or together with the nitrogen to which they are attached form a 5 to 7 membered ring which may optionally contain one or more heteroatoms.

3. Compounds according to claim 1 or Z in which m is 1 and n is 0 and x is 0.

4. Compounds according to claims 1, 2 or 3 in which R 1 is chlorine.

5. Compounds according to any preceding claim in which p is 0 and at least one of R 2 and R 4 is an acyl, ester or thioester group.

6. Compounds according to claim 3 in which p is 0, R^ is halo, 2 4 *3 R is hydrogen and R is acyl or alkoxycarbonyl and R is alkyl.

7. Compounds according to claim 1 wherein p = 3, x = 0, R 2 is hydrogen, R^ and R 5 are halo, R 4 is hydrogen, acyl or alkoxyq carbonyl and R is alkyl, optionally substituted phenyl or optionally substituted benzyl. q

8. Compounds according to claim 6 in which R is 0μ 4 alkyl optionally substituted by halogen. q

9. Compounds according to claim 8 in which R is methyl or tri fluoromethyl.

10. Compounds according to any one of the preceding claims in which R is hydrogen and R is not hydrogen.

11. Compounds according to claim 10 in which R 4 is of formula R°(0) q C0 where q is 0 or 1, R is C^^ alkyl, optionally substituted by C 1-4 alkoxy, C 3 _ ? cycloalkyl, halogen, phenoxy or substituted phenoxy; C 3 _ 7 cycloalkyl; C^-12 alkenyl, optionally substituted by phenyl or substituted phenyl; C 2 _ 6 alkynyl, or optionally substituted phenyl, wherein any substituted phenyl group is substituted by C 1-4 alkyl, C^ haloalkyl, nitro, 0μ 4 alkoxy, C-|_4 alkylthio, dialkylamino, phenyl or halogen, and when q is 0, R is also hydrogen.

12. The compound 4-chloro-4'-methylsulphonyloxybenzophenone formyl hydrazone. 5

13. The compound 4-chloro-4'-methylsulphonyloxybenzophenone ethoxycarbonyl hydrazone.

14. The compound 4-chloro-4'-trifluoromethyl sulphonyloxybenzophenone ethoxycarbony1 hydrazone.

15. A pesticidal composition comprising a compound according to 10 any of claims 1 to 14 and an inert diluent or carrier.

16. A method of combating pests such as insects or acarids which comprises applying a compound according to any of claim 1 to 14 to the locus of the pest.

17. A method according to claim 16 for protecting plants from attack 15 by insects which comprises applying the compound to the plant.

18. A method according to claim 16 for protecting livestock from attack by insect or acarid parasites which comprises applying the compound to the parasites.

19. A process for the preparation of a compound according to claim 1 20 which comprises reacting a compound of formula II 48748 with a compound of formula NH 2 NR 2 R 4 , and when R 2 and R 4 are both hydrogen (i) when p is 0, the product is acylated or (ii) when p is 2 or 3 the product is optionally acylated, the acylation being carried out with a) an acyl halide or acid anhydride Λ 5 when R or R* is to be an acyl group, with b) an ester residue halide when R 2 or R 4 is to be an ester group, or with c), an isocyanate or 2 4 isothiocyanate when R or R is to be an optionally substituted carbamoyl group or a substituted thiocarbamoyl group.

20. A process for the preparation of a compound according to 10 claim 1 wherein p is 3 comprising reacting a compound of formula IV in which R 2 and R 4 are not both hydrogen with a compound of formula RS0 2 Y in which Y is halogen, preferably chlorine.

21. 22. A process for the preparation of a compound of claim 1, substant15 ially as described herein with reference to the Examples.

22. 23, A compound according to claim 1 whenever prepared by a process as claimed in any one of claims 19 to 21.