PYRAZOLINE INSECTICIDES

Abstract: Insecticidal compounds of formula I where R¹ is hydrogen, alkyl or alkenyl; X is oxygen or sulphur; each R², which may be the same of different, is halogen, alkyl, haloalkyl, cyano, nitro, alkoxy, haloalkoxy, alkylthio, haloalkylthio, alkylsulphonyloxy, alkylsulphonyl, alkoxycar­ bonyl or acyl or two adjacent R² groups together with the carbons to which they are attached form a 5 to 7 membered ring which may comprise one or more oxygen atoms and may be substituted; m is 0 to 4; either a) R a is hydrogen and one of R b and R c is phenyl, para substituted by the group R⁴, and the other is hydrogen; or b) R a and R b are both alkyl and R c is phenyl para substituted by the group R⁴; R⁴ and R⁵ which may be the same or different, are R⁸SO₂O, hydrogen, halogen, alkyl, haloalkoxy, alkylthio or alkylsulphonyl, wherein R⁸ is alkyl or haloalkyl; with the proviso that at least one of R⁴ and R⁵ is R⁸SO₂O or at least R⁴ is haloalkoxy.

Description: PYRAZOLINE INSECTICIDES This invention relates to new compounds having insecticidal activity. Various pyrazoline derivatives have been disclosed as having insecticidal activity. The closest prior art to the compounds of the present invention is described in European Patent Specification No. 58424 which claims compounds having the formula EMI1.1 wherein R represents hydrogen. a lower alkyl group, z phenyl group a a halogen-substituted phenyl group, a cyanoalkyl group or a lower alkoxyalkyl group: R and R3 respectively represent hydrogen a lower alkyl group, a phenyl group or a halogen-substituted phenyl group: R4 represents hydrogen or a lower alkyl group; X represents hydrogen or halogen: W represents oxygen or sulphur; Y and Z respectively represent hydrogen, a halogen, a lower alkyl group. a lower alkoxy group a a nitro group, a trifluoromethyl group a a lower alkylthio group a an acyl group a a nitrile group, a lower alkylsulphonyl group a a lower alkoxycarbonyl group a -A-R or Y and Z form -0-aH2 -0-; and A represents -0-, -S-, -SO- or -SO - and 5 represents a halogen-substituted lower alkyl group. The compounds of the present invention often have advantages over compounds of the prior art and in particular where we have compared compounds of the present invention over their isomers in the above patent specification we have found unexpected improvements in certain activities. We are also not aware of any pyrazoline compounds of this type which contain phenyl groups on the 3, 4 or 5 position which carry a sulphonyloxy group. Thus according to the invention there are are provided compounds of formula I EMI2.1 where R is hydrogen, alkyl or alkenyl; X is oxygen or sulphur; each R2, which may be the same or different, is halogen, alkyl, haloalkyl, cyano, nitro, alkoxy, haloalkoxy, alkylthio, haloalkylthio, alkylsulphonyloxy, alkylsulphonyl, alkoxycarbonyl or acyl or two adjacent Rê groups together with the carbons to which they are attached form a 5 to 7 membered ring which may comprise one or more oxygen atoms and may be substituted; m is 0 to 4; either a) Ra is hydrogen and one of Rb and RC is phenyl, para substituted by the group R4 , and the other is hydrogen; or b) Ra and Rb are both alkyl and Rc is phenyl para substituted by the group R4 ; R4 and R5 which may be the same or different. are R8SO2O, hydrogen, halogen, alkyl, haloalkoxy, alkylthio or alkylsulphonyl, wherein R is alkyl or haloalkyl; wih the proviso that at least one of R4 and R5 is R8SO2O or at least R4 is haloalkoxy. When R4 is haloalkoxy it is particularly preferred that it is difluoromethoxy. Particularly preferred groups for R8 are methyl and trifluoromethyl. Alkyl, alkoxy, alkylthio, haloalkyl and haloalkoxy are generally ofCl¯a carbon atoms. Preferably Ra and Rb are hydrogen. A particularly preferred group of compounds are these in which R5 is hydrogen or halogen. especially chlorine or fluorine. Generally m is 1 and R2 is in the para position. Preferred R groups are chlorine, fluorine, bromine or methylthio and especially trifluoromethyl. The compounds of the invention have insecticidal activity and are particularly useful in combating a variety of economically important insects, e.g. Lepidoptera, including larvae of Spodootera littoralis, Heliothis spp (e.g. Heliothis armiqer), Plutella ixylostella, Pieris brassicae. grape berry moths, eg. Eutoecilia ambiquella) and loopers (e.g. Trichotlusia ni) Diptera, including Musca domestica, Ceratatis caPitata and Aedes aeqytti; Homoptera, including hoppers e.g. Nilitarvata luqens; Coleoptera, including Phaedon cochleariae and the boll weevil (Anthonomus Qrandis); Orthoptera and Dictyoptera, including Blattella Qermanica and Hymenoptera, especially ants, such as Solenopsis spp., Atta spp and Monomorium spp. The compounds also have activity against human and animal ectoparasites, such as blowfly (Lucilia spp,) and lice e.g. Damalinia bovis. The invention also includes an insecticidal composition which comprises a compound of formula I in association with an agronomically acceptable diluent or carrier. More than one compound of the invention can, of course, be included in the composition. In addition the composition can comprise one or more additional pesticides, for example compounds known to possess herbicidal, fungicidal, insecticidal, acaricidal or nematicidal properties. Alternatively the compounds of the invention can be used in sequence with the other pesticides. Insecticides and acaricides which can be used in conjunction with the compounds of the invention include natural and synthetic pyrethroids (such as the natural pyrethrins, allethrin, bioallethrin, resmethrin, bioresmethrin, tetramethrin, furamethrin, fenpyrithrin, permethrin, cypermethrin, deltamethrin, fenvalerate, alphamethrin, phenothrin, fenpropathrin, flumethrin, empenthrin. pral lethrin, tralocythrin, tralomethrin, flucythrinate, fluvalinate, cyfluthrin and cyhalothrin), organophosphorus compounds (such as tetrachlorvinphos, fenitrothion, malathion, dialifos, chlorfenvinphos, dioxathion, demeton-S-methyl. phosalone,dichlorovos, bromophos-ethyl, diazinon, dimethoate, sulprofos, acephate. chlorpyrifos. crufomate, heptenophos, naled, phenthoate, phorate, terbufos, pirimiphos-ethyl, pirimiphos-methyl, parathion-methyl, temephos, famphur, chlormephos. coumaphos, fenthion and phosmet), carbamates (such as bendiocarb, carbofuran, aldicarb, carbaryl, pirimicarb, promecarb, propoxur, formetanate, methomyl, oxamyl, thiofanox. bufencarb, thiodicarb, carbosulfan and dimetilan), chlorinated compounds1 (such as toxaphene, endosulphan, HCH and DDT) and miscellaneous compounds including amitraz, chlormethiuron, endosulphan, cyhexatin, diflubenzuron, chlordimeform. benzoximate, dicofol, propargite and clofentezine. The diluent or carrier in the composition of the invention can be a solid or a liquid optionally in association with a surface-active agent, for example a dispersing agent1 emulsifying agent or wetting agent. Suitable surface-active agents include anionic compounds such as a carboxylate. for example a metal carboxylate of a long chain fatty acid; an N-acylsarcosinate; mono- or di-esters of phosphoric acid with fatty alcohol ethoxylates or salts of such esters; fatty alcohol sulphates such as sodium dodecyl sulphate a sodium octadecyl sulphate or sodium cetyl sulphate; ethoxylated fatty alcohol sulphates; ethoxylated alkylphenol sulphonates; lignin sulphonates; petroleum sulphonates; alkyl-aryl sulphonates such as alkyl-benzene sulphonates or lower alkylnaphthalene sulphonates, e.g. butyl-naphthalene sulphonate; salts of sulphonated naphthalene-formaldehyde condensates; salts of sulphonated phenol-formaldehyde condensates; or more complex sulphonates such as the amide sulphonates, e.g. the sulphonated condensation product of oleic acid and N-methyl taurine or the dialkyl sulphosuccinates, e.g. the sodium sulphonate of dioctyl succinate. Nonionic agents include condensation products of fatty acid esters, fatty alcohols, fatty acid amides or fatty-alkyl- or alkenyl-substituted phenols with ethylene oxide, fatty esters of polyhydric alcohol ethers, e.g. sorbitan fatty acid esters1 condensation products of such esters with ethylene oxide, e.g. polyoxyethylene sorbitan fatty acid esters, block copolymers of ethylene oxide and propylene oxide. acetylenic glycols such as 2,4,7,9-tetramethyl-5-decyn-4,7-diol, or ethoxylated acetylenic glycols. Examples of a cationic surface-active agent include, for instance, an aliphatic mono-, di-, or polyamine as an acetate, naphthenate or oleate: an oxygen-containing amine such a amine oxide or polyoxyethylene alkylamine; an amide-linked amine prepared by the condensation of a carboxylic acid with a di- or polyamine; or a quaternary ammonium salt. The compositions of the invention can take any form known in the art for the formulation of insecticidal compounds, for example, a solution, a dispersion, an aqueous emulsion, a dusting powder, a seed dressing, a fumigant, a smoke. a dispersible powder, an emulsifiable concentrate, granules or baits. Moreover it can be in a suitable form for direct application or as a concentrate or primary composition which requires dilution with a suitable quantity of water or other diluent before application. As a dispersion, the composition comprises a compound of the invention dispersed in a liquid medium, preferably water. It is often convenient to supply the consumer with a primary composition-which can be diluted with water to form a dispersion having the desired concentration. The primary composition can be provided in any one of the following forms. An emulsifiable concentrate comprises a compound of the invention dissolved in a water-immiscible solvent together with an emulsifying agent and which is formed into an emulsion on mixing with water. A dusting powder comprises a compound of the invention intimately mixed with a solid pul-verulent diluent, for example, kaolin. A granular solid comprises a compound of the invention associated with similar diluents to those which may be employed in dusting powders, but the mixture is granulated by known methods. Alternatively it comprises the active ingredient adsorbed or absorbed on a pre-granular diluent, for example, Fuller's earth, attapulgite or limestone grit. A wettable powder usually comprises the active ingredient in admixture with a suitable surfactant and an inert powder diluent such as china clay. Another suitable concentrate, particularly when the product is a solid. is a flowable suspension concentrate which is formed by grinding the compound with water or an oil. a wetting agent and a suspending agent. Baits can include an attractant and may comprise a protein hydrolysate e.g. for the control of fruit flies, sugar e.g. for the control of adult Musca spp. or peanut butter or corn cob e.g. for the control of cockroaches or ants. The concentration of the active ingredient in the composition of the present invention is preferably within the range of 1 to 30 per cent by weight, especially 5 to 30 per cent by weight. In a primary composition the amount of active ingredient can vary widely and can be, for example, from 5 to 95 per cent by weight of the composition. The compounds of the invention may be prepared by reacting a compound of formula II EMI10.1 (i) with phosgene or thiophosgene followed by a compound of formula EMI10.2 or (ii) with a compound of formula EMI11.1 where R11 and R12 form a double bond when R1 is hydrogen, or R11 is R1 and R12 is chlorine. Alternatively a compound of formula III EMI11.2 can be reacted with a compound of formula IV EMI11.3 Compounds where R1 is hydrogen can be subsequently alkylated or alkenylated e.g. by reaction with an alkyl or alkenyl halide under basic conditions. The above reactions may suitably be carried out at a temperature of 0 - 1000C. The compounds of formula II are novel and form part of the invention. They may be prepared by reacting a compound of formula III with hydrazine. The compounds of formula III in which Rc is substituted phenyl may be prepared by reacting a compound of formula V EMI12.1 with a compound of formula RaRb CO, e.g formaldehyde. Compounds in which Ra and Rb are alkyl are usually prepared by reaction of V with a compound Ra Rb CHI, followed by halogenation eg. with bromine, and dehydrohalogenation, eg using lithium chloride. Compounds of formula V may be prepared from the corresponding hydroxy compound, by sulphonation or by reaction with a polyhaloalkane. Those compounds in which Rb is substituted phenyl may be prepared by reacting a compound of formula EMI13.1 with a compound of formula EMI13.2 Compounds which comprise an alkylsulphonyl group may be obtained by oxidising the corresponding compound comprising an alkylthio group, using a suitable oxidising agent such as hydrogen peroxide. The invention is illustrated in the following Examples. Structures of isolated novel compounds were confirmed by elemental and/or other appropriate analyses. ExamPle 1 Methanesulphonyl chloride (26 ml) was added dropwise to a solution of l-(4-chlorophenyl)-2-(4-hydroxyphenyl) ethanone (42 g) in pyridine (120 ml). The mixture was heated under reflux for 2 hours and then poured iwto an ice hydrochloric acid mixture. The product was filtered off, dried and recrystallised from ethanol to give l-(4-chlorophenyl)-2-(4-methylsulphonyloxyphenyl)ethanone m.p. 135-1370C (Intermediate A). This product (26 g) was suspended in methanol and aqueous formaldehyde (37% w/v, 24 ml), piperidine (0.9 ml) and glacial acetic acid (0.9 ml) successively added. The mixture was stirred at room temperature for ten minutes and then heated under reflux for 4 hours. Methanol was distilled out and the residue poured into ice/water to give a gummy deposit and an emulsion. The latter was decanted and sodium chloride added and the mixture stood overnight. The resulting precipitate was filtered and dried. This was combined with material obtained by triturating the gummy deposit with ethanol, to give 1-(4-chlorophenyl) 2-(4-methylsulphonyloxyphenyl)-2-propen-l-one , m.p. 65-700C (Intermediate B). A mixture of this product (11.7 g), hydrazine hydrate (3.4 ml) and propanol (17 ml) was heated on a steam bath for 4 hours and the mixture filtered while hot. The filtrate was cooled and ice-cold methanol (15 ml) added. The solid material which formed was collected washed with ethanol and dried, to give crude 3-(4-chlorophenyl)-4-(4-methylsulphonyloxyphenyl)-2-pyrazoli ne (Intermediate C). This was suspended in dry ether and 4-chlorophenyl isocyanate (3.85 g) added followed by a few drops of triethylamine. The mixture was cooled in an ice-bath for 1 hour and then stirred overnight at room temperature.The solid material was collected and recrystallised from ethyl acetate to give N,3-bis (4-chlorophenyl)-4-(4-methylsulphonyloxyphenyl) -2-pyrazoline-l-carboxamide, m.p. 205-70C (Compound 1). In a similar manner the following products were obtained. Compounds containing a methylsulphonyl group were obtained by oxidising the corresponding compound containing a methylthio group using aqueous hydrogen peroxide in acetic acid. Compounds in which R is methyl were obtained by treating the corresponding compound where R is hydrogen with methyl iodide in the presence of sodium hydride and dimethyl formamide (in the case of sulphonyloxy containing compounds) or in the presence of potassium hydroxide and acetone. Compounds in which R1 is alkyl were obtained from the corresponding compound where R1 is hydrogen by reaction will alkyl bromide in the presence of potassium hydroxide. The position of the R4 containing phenyl is given in the column headed A. EMI16.1 Cpd. X R5 R1 R4 A R R2 R10 m.p. No. ( C) 2 O Cl H CF3SO2O 4 H Cl H 154-6 3 0 Cl H CF3SO2O 4 H F H 150-2 4 S Cl H CF3SO2O 4 H Cl H 184-7 5 O Cl H CF3SO2O 4 Cl H H 140-4 6 0 Cl H CF3SO2O 4 H H H 139-42 7 O Cl H CF3SO2O 4 Cl Cl H 175-7 8 0 H H MeSO2O 4 H Cl H 165-8 9 O H H MeSO2 0 4 H OMe H 118-21 10 0 H H MeSO2O 4 H CN H 160-4 11 S H H MeSO2O 4 H Cl H 164-8 12 0 H H MeS020 4 H Br H 139-42 13 O Cl H MeSO2O 4 H NO2 H 108-11 14 0 Cl H MeSO2O 4 H OMe H 144-7 Cpd. X R5 R1 R A R9 R2 R10 m.p. No. ( C) 15 0 F H MeSO2O 4 H C1 H 169-73 16 0 F H MeSO2O 4 H Br H 140-3 17 0 C1 H MeSO2O 4 H CN H 165-8 18 0 H H CF3SO2O 4 H Cl H 125-8 19 0 Me H MeSO2O 4 H Cl H 193-5 20 0 H H CF3 SO2O 4 H Br H 129-31 21 0 Me H MeSO2O 4 H Br H 184-8 22 0 Cl H CF3SO2O 4 H Br H 162-3 23 0 Cl H CF3SO2O 4 CF3 H H 179-83 24 0 Cl H CF3SO2O 4 H Me H 176-8 25 O F H CF3SO2O 4 H Cl H 138-40 26 0 F H CF3SO2O 4 H F H 133-5 27 0 MeS H MeSO2O 4 H Cl H 129-32 28 0 F H CF3SO2O 4 H Br H 138-40 29 O Me H CF3SO2O 4 H Cl H 174-5 30 0 Me H CF3SO2O 4 H F H 163-5 31 0 Me H CF3 SO2O 4 H Br H 181-2 32 0 MeS H CF3S020 4 H Br H 154-7 33 0 Cl H CHF2O 4 H Cl H 135-7 34 0 Cl H CHF2O 4 H F H 141-3 Cpd. X R5 R1 R4 A R R2 R10 m.p. No. ( C) 35 0 C1 H CHF2O 4 H Br H 148-50 36 0 C1 H CHF2O 4 Cl H H 137-9 37 0 Me H CHF2O 4 H F H 139-40 38 0 Me H CHF2O 4 H C1 H 140-2 39 0 Me H CHF2O 4 H Br H 136-8 40 O MeSO2O H Cl 4 H Cl H 140-2 41 0 MeSO2O H F 4 H Cl H 150-3 42 0 MeSO2O H H 4 H Cl H 138-40 43 0 MeSO2O H Cl 4 H Br H 166-70 44 0 CHF2O H CHF2O 4 H Cl H 101-4 45 0 H H CHF2O 4 H Cl H 136-9 46 0 F H CHF2O 4 H Cl H 114-6 47 0 MeS H CHF2O 4 H Br H 110-3 48 0 H H CHF2O 4 H Br H 136-9 49 0 MeS H CHF2O 4 H Cl H 112-3 50 s Cl H CHF2O 4 H Cl H 175-7 51 0 Cl H CHF2O 4 H Me H 180-3 52 0 Cl H CHF2O 4 H No2 H 191-4 53 0 F H CHF2O 4 CF3 H H 140-1 54 0 F H MeSO2O 4 H Pri H 167-9 Cpd. x R5 RÚ R4 A R9 R2 H10 n.p. No. ( C) 55 0 F H MeSO2O 4 H I H 188-91 56 0 F H CHF2O 4 .H Br H 140-2 57 0 F H CHF2O 4 Cl Cl H 130-3 58 0 Cl H CHF2O 4 -OCH2O- H 187-9.5 59 O Cl H CHF2O 4 H MeS H 154-6 60 0 Cl H CHF2O 4 H CN H 179-82 61 0 F H MeSO2O 4 H CF3 H 173 62 0 Cl H CHF2O 4 H CF3 H 135-7 63 0 Cl H CHF2O 4 H COOPr H 163-6 64 0 Br H CHF2O 4 H CF3 H 134-5 65 0 Br H CHF2O 4 H Cl H 141-4 66 0 Br H CHF2O 4 H COOPr H 163-5 67 0 Cl H CHF2O 4 CF3 H H 137-40 68 0 H H CHF2O 4 H F H 126-8 69 0 H H CHF2O 4 H CF3 H 123-5 70 0 H Me CHF2O 4 H CF3 H 129-31 71 0 H H CHF2O 4 H Pr H 112-4 72 0 H H CHFzO 4 H COOPr H 142.5-5 73 0 Cl H CHF2O 4 H Pr H 129-32 74 0 Cl H CHF2O 4 H EtSO2O H 178-80 Cpd. X R5 RÚ R4 A R9 Rê R10 m.p. No. ( C) 75 0 H Me CHF2O 4 H Br H 109-10 76 0 Cl H CHF2O 4 -H Cl Me 141-3 77 O Cl Me CHF2O 4 H Cl H 119-20 78 d F H MeSO2O 4 H CHF2 0 H 167-70 79 0 Cl H CF2HCF2O 5 H Pri H 171-3 80 0 Cl H CF2HCF2O 5 H COOPr H 146-9 81 0 Cl H CF2HCF2O 5 H F H 172-4 82 0 F H MeSO2O 4 Cl F H 169-72 83 0 H H CHF2O 4 H COCH3 H 183-4 84 0 Cl H CF2HCF2O 5 H SMe H 186-90 85 0 Cl H CF2HCF2O 5 -OCH2O- H 165-7.5 86 0 Cl H CF2HCF2O 5 H CN H 225-6 87 0 H H CHF2O 4 H Me H 158-61 88 0 Cl H CF2HCF2O 5 H Cl H 166-8 89 0 MeSO2 H CHF2O 4 H Cl H 205-7 90 0 Cl H CHF20 5 H Pr H 144-6 91 0 F Me MeSO2O 4 H Cl H 124-5 92 S Cl H CHF2O 5 H Cl H 173-6 93 0 Cl H CHF2O 5 H F H 168-71 94 0 Cl H CHF2O 5 H Cl H 216-7 Cpd. X R5 RÚ R4 A R9 Rê R10 m.p. No. ( C) 95 0 H H CHF20 4 H EtSO2O H 153-5 96 0 H H CHF2O 4 H Cl Me 177-9 97 0 C1 allyl CHF2O 4 H C1 H oil 98 0 Cl H CHF2O 4 H CHF2O H 127-30 99 0 H H CHF2O 4 H CF2HCF2O H 160-1 100 0 H H CHF2 0 4 H CF 2BrO H 140-2 101 0 Cl H CHF20 4 H CF2BrO H 175-6.5 102 0 Cl H CHF2O 4 H CF2HCF2O H 179-80.5 103 0 Cl H CF3CH20 4 H C1 H 168.5-70 During the course of preparation of the above, various intermediates were prepared. In many cases they were not isolated but used in the next stage without purification, the structures having been confirmed by n.m.r. The physical properties of these intermediates of compounds where the R4-containing phenyl is in the 4 position are as follows. Temperatures are melting points in 0 C. R5 R4 Type A Type B Type C Cl MeSO2O 135-7 65-70 C1 CF3SO2O 100-3 oil 105-9 H MeSO2O 97-8 F MeSO2O 150-5 oil H CF3SO2O 90-2 oil 80-2 F CF3SO2O oil 104-6 MeS MeSO2O oil 111-8 Me CF3SO2O 126-8 oil MeS CF3SO2O oil Cl CHF2O 71-73 MeSO2O F 128-30 oil MeSO2O H oil 152-4 CHF2O CHF2O oil F CHF2O oil H CHF2O 88-92,5 oil oil MeS CHF2O 130-3 oil Br CHF2O oil Type A intermediates in which R4 or R5 are CF3SO2O were prepared using trifluoromethanesulphonic anhydride or fluoride, instead of the sulphonyl chloride. Type A intermediates in which R4 is CHF2O were prepared by bubbling chlorodifluoromethane into a mixture of the corresponding hydroxy compound with aqueous sodium hydroxide and dioxan, at elevated temperature for 3 hours. The mixture was then heated for a further period and then kept overnight at room temperature, after which it was poured into water and the product obtained by a conventional work-up procedure. For these compounds in which the R containing phenyl is in the 5 position the type B intermediate was obtained by reacting a 4-haloalkoxy benzaldehyde with a 4-substituted acetophenone in the presence of aqueous sodium hydroxide at room temperature. In this way the following were obtained. a) 1-(4-chlorophenyl)-3-[4-(1,1,2,2-tetrafluoroethoxy) phenyl)-2-propen-l-one, m.p. 100-20C. b) l-(4-chlorophenyl)-3-(4-difluoromethoxyphenyl) -2-propen-l-one, m.p. 105-80C. The type C intermediates were obtained from these by reaction with hydrazine hydrate. Since the products were unstable they were used in the next stage without purification. ExamPle 2 Sodium hydride (3.4 g of an 80% dispersion in oil) was added portionwise to 1-(4-chlorophenyl)-2-(4-difluormethoxylphenyl) ethanone (24.3g) in tetrahydrofuran. The mixture was stirred for Yi hour at room temperature and isopropyl iodide (8.8 ml) added dropwise. The mixture was heated under reflux for 4 hours and then filtered and evaporated. The residue was added to ether (150 ml) and water (50 ml). The ether layer was dried and evaporated and the residue subjected to flash column chromatography to give 1-(4-chlorophenyl)-2-(4-difluromethoxyphenyl)-4-methylbutan one, obtained as a yellow oil. Bromine (2.5 ml) was added dropwise to this (14.4 g) in carbon tetrachloride. The mixture was stirred at room temperature for 24 hours and then evaporated. Dimethylformanide (75 ml) and lithium, chloride (8.7 g) were added portionwise and the mixture heated at 1300C for 3 hours It was then cooled, poured into water and extracted with ether. The extracts was dried and evaporated and the residue subjected to flash column chromatography to give 1-(4-chlorophenyl)-2-(4-difluoromethoxyphenyl)-4-methyl 2-buten-1-one. obtained as an orange oil. Hydrazine hydrate (15.2 ml of a 64% solution) was added and the mixture stirred under nitrogen and in the dark for 24 hours. The mixture was then evaporated, ether (200 ml) and water (200 ml) added and the ether layer dried and evaporated to give crude 3-(4-chlorophenyl)-4-(difluoromethoxyphenyl)-5, 5-dimethyl-2-pyrazoline. This was then treated with the appropriate phenylisoyanate as described in Example 1 to give the following EMI25.1 Compound No R2 mg( C) 201 SCH3 119-20 202 Pr 138-40 203 C1 144-5 204 COOPr 135-7 Example 3 This example illustrates an alternative route to compounds of the invention in this case Example 1 compound 1. Intermediate C to Example 1 compound 1 (4.lg) was dissolved in tetrahydrofuran (50 ml) and phosgene (3 ml) in tetrahydrofuran (20 ml) was added dropwise whilst maintaining the temperature at 10-200C. The mixture was then stirred at room temperature for 60 hours, washed with water and the organic layer separated. dried and evaporated. The residue was subjected to flash chromatograpy. The product was triturated with diiopropyl ether to give N,3-bis (4-chlorophenyl) 4-(4-methylsulphenyloxyphenyl )-2-pyrazoline-1-carboxamide, mp 199-200"C. ExamPle 4 N-methyl-N-phenyl carbamoyl chloride (1.0 g) was added partionwise to a stirred solution of intermediate C to Example 1, compound 1 (2.0 g) in pyridine (5 ml). The mixture was cooled in an ice-bath for 20 minutes, stirred for 1 hour, added to water (150 ml) and extracted with dichloromethane. The extract was washed with dilute hydrachloric acid and water, dried and evaporated. The residue was subjected to flash chromatography and the resulting oil triturated with ether to give N-methyl-N-phenyl-3- (4-chlorophenyl)-4- (4-methylsulphonyloxyphenyl )-2-pyrazoline-l-carboxamide, mp. 162-30C (Compound 401). In a similar manner there was obtained N-methyl-Nphenyl-3-(4-chlorophenyl)-4-(4 trifluoromethylsulphonyloxyphenyl)-2-pyrazoline-1- carboxamide, mp 113-40C. (Compound 402). Example 5 Aliquots of acetone solutions of test compounds at various concentrations were applied to 9 cm diameter filter papers placed in the bottom of 9 cm diameter glass dishes closed by glass lids. The treated surfaces, together with controls treated with acetone alone, were then infested with adult houseflies, (Musca domestica) and held at 250C for 24 hours. The percentage mortality of the insects was then recorded. Compounds 2, 18. 20, 22, 23, 25, 26, 28, 33, 34, 35, 38, 39, 45, 46, 49, 56, 57, 59, 62, 64, 65, 68, 70 and 75 have an LD50 of less than 1000 mg/mê of filter paper. Compounds 33 and 45 were compared with their isomers disclosed in EP 58424. The results were as follows. In all these compounds X. RÚ, R9 Rê and R10 are the same. The differences are that the groups at R and R are reversed. Compound of Invention Compound of EP 58424 R4 R LD50 (mg/rn2) R R LD50 (mg/mê 33 CHF2O Cl 300-1000 Cl CHF2O > 1000 45 CHF2O H 100-300 H CHF2O > 1000 Example 6 Cabbage leaves were dipped in aqueous dispersions at various concentrations of test compound and the leaves allowed to dry. The dispersions contained 500 mg/litre of an ethylene oxide/nonylphenol wetting agent. Each leaf was placed in a petri dish with a lid and 10 second instar larvae of Spodottera littoralis applied to each leaf. After three days untreated leaves are added to each replicate. Two days later an assessment was made of the mortality. Two replications were carried out at each concentration of each compound and an LD50 calculated. Compounds 1-3, 5-8, 11-22. 24-57, 58, 59-62, 64, 65, 68, 71, 74, 75, 81 and 88 have an LD50 of less than 300 mg/litre. ExamPle 7 Compounds were tested in a similar manner to Example 6 but using Heliothis armiser fed on tobacco leaves. Compounds 1-8, 15-18, 20, 22-26, 28, 29, 31, 33-36, 40. 41, 43-46. 49, 50, 54-56, 58-62, 65, 69 and 88 have an LD50 of less than 300 mg/litre. Example 8 Third instar larvae of the diamond-backed moth, Plutella xylostella were ingested onto cabbage leaves and 24 hours later the plant and larvae were sprayed with dispersions of compound as described in Example 3. After drying ingested leaves were placed in petri dishes. An assessment of mortality was made 5 days later. Compounds 1-18. 20-40. 42-69, 70-79 and 81-84 had a LD50 of less than 1000 mg/litre. Example 9 1 ml aliquots of an acetone solution containing test compound at various concentrations were applied to cotton wool dental rolls 1 cm x 2 cm, contained in glass vials 2 cm diameter x 5 cm long. After drying, the treated materials were then impregnated with 1 ml of nutrient solution, infested with third instar larvae of the Mediterranean fruit-fly, (Ceratitis caPitata) or first instar larvae of sheep blow fly (Lucilia sericata), closed by a cotton wool plug and held at 250C for 24 hours. The percentage mortality of the insects was then recorded. Compounds 1-6, 8-22, 28-35, 38, 39, 41 and 42 have an LD50 of less than 100 mg/litre against Ceratitis caPitata and compounds 44-69, 70, 71, 73-86 and 95-97 have an LD50 of less than 1000 mg/litre against Lucilia sericata. In all the test Examples, less then 5% mortality was recorded for the controls. Example 10 This example illustrates typical formulations using the compound of the invention Wettable Powder concentrate % w/w Compound No 33 25 Sodium lignosulphonate 5 China clay 70 Bait % w/w Wettable powder concentrate from above to give active ingredient content of 0.4 Apple pomice 37.2 Rolled bran 37.2 Plain white flour to 100 Different compounds were also formulated in a similar manner and at various concentrations.

Claims: Claims 1) Compounds of formula I EMI32.1 where R1 is hydrogen, alkyl or alkenyl; X is oxygen or sulphur; each Rê. which may be the same or different, is halogen, alkyl, haloalkyl, cyano, nitro, alkoxy, haloalkoxy, alkylthio, haloalkylthio, alkylsulphonyloxy, alkylsulphonyl, alkoxycarbonyl or acyl or two adjacent Rê groups together with the carbons to which they are attached form a 5 to 7 membered ring which may comprise one or more oxygen atoms and may be substituted; m is O to 4; either a) R is hydrogen and one of Rb and Rc is phenyl, para substituted by the group R4, and the other is hydrogen; or b) Ra and Rb are both alkyl and Rc is phenyl para substituted by the group R4; R4 and R5 which may be the same or different, are R8SO2O. hydrogen, halogen, alkyl. haloalkoxy, alkylthio or alkylsulphonyl, wherein R8is alkyl or haloalkyl; with the proviso that at least one of R4 and R5 is R8SO2O or at least R4 is haloalkoxy. 2) Compounds according to claim 1 in which Ra and Rb are hydrogen. 3) Compounds according to claim 1 or 2 in which R5 is hydrogen or halogen. 4) Compounds according to claim 1, 2 or 3 in which H4is difluoromethoxy. 5) Compounds according to claim 1 in which m is 1 and This in the para position. 6) Compounds according to claim 5 in which Rê is chlorine, fluorine, bromine, methylthio or trifluoromethyl. 7) Compounds according to any one of the preceding claims in which R1 is hydrogen. 8) N,3-Bis(4-chlorophenyl)-4-(4-difluoromethoxyphenyl) -2-pyrazoline-1-carboxamide. 9) 3-(4-chlorophenyl)-4-(4-difluoromethoxyphenyl) N-(4-trifluoromethylphenyl)-2-pyrazoline-l- carboxamide. 10) 4-(4-Difluoromethoxyphenyl)-3-phenyl-N (4-trifluoromethylphenyl)-2-pyrazoline-l-carboxamide. 11) An insecticidal composition comprising a compound as claimed in any one of the proceding claims in association with an agronomically acceptable carrier. 12) A method of combating insects which comprises applying to the insects or their locus a compound claimed in any one of claims 1 to 10. 13) Compounds of formula II EMI35.1 in which Ra, Rb, Rc, and R5 have the meanings given in claim 1.

Inventors: GILES, DAVID PETER, WILLIS, ROBERT JOHN
Applicants: SCHERING AGROCHEMICALS LIMITED
Application year: 1983
Main classification: C07D231
IPC codes: C07C45, C07D405, A01N43, C07C49, A01N47, C07D231