WO1997011952A1 - Fungicides - Google Patents

Abstract

A compound of formula (I) wherein A?1 and A2¿ are, independently, phenyl, furyl or thienyl each optionally substituted by halogen, C¿1-4? alkyl, C1-4 alkoxy, C1-4 alkylthio, C1-4 haloalkyl, C1-4 haloalkoxy or C1-4 haloalkylthio; R is C1-4 alkyl, C1-4 haloakyl, C2-4 alkenyl, C2-4 haloalkenyl, C3-7 cycloalkyl, C3-7 cycloalkyl(C1-4)alkyl, benzyl or phenyl, wherein benzyl and phenyl are optionally substituted by halogen, C1-4 alkyl, C1-4 haloalkyl, C1-4 alkoxy or C1-4 haloalkoxy; and R?1, R2, R3 and R4¿ are, independently, hydrogen, C¿1-8? alkyl, C1-8 haloalkyl, C1-8 alkoxy, C1-8 haloalkoxy, halogen, nitro, COR?7, NR5R6¿, benzyl or phenyl (wherein benzyl and phenyl are optionally substituted by halogen, C¿1-4? alkyl, C1-4 haloalkyl, C1-4 alkoxy, C1-4 haloalkoxy or NR?5R6); R1 and R2 or R2 and R3¿ may join together to form a ring, the ring being optionally substituted by halogen, C¿1-4? alkyl, C1-4 haloalkyl, C1-4 alkoxy, C1-4 haloalkoxy or nitro; and R?5, R6 and R7¿ are independently hydrogen or C¿1-4? alkyl; provided that at least one of R?1 and R4¿ is hydrogen.

Description

FUNGICIDES

The present invention provides pyrazolylborane derivatives of formula (I), processes for their preparation, compositions comprising them, and methods of using them to combat fungi, (especially fungal infections of plants), insects, acarine pests, nematodes, mites or micro-organisms.

The present invention provides a compound of formula (I)

wherein A¹ and A² are, independently, phenyl, furyl or thienyl each optionally substituted by halogen. C_1-4 alkyl, C_1-4 alkoxy, C_1-4 alkylthio, C_1-4 haloalkyl, C_1-4 haloalkoxy or C_1-4 haloalkylthio; R is C_1-4 alkyl, C_1-4 haloalkyl, C_2-4 alkenyl, C_2-4 haloalkenyl, C₃.7 cycloalkyl, C_3-7 cycloalkyl(C_1-4)alkyl, benzyl or phenyl, wherein benzyl and phenyl are optionally substituted by halogen, C_1-4 alkyl, C_1-4 haloalkyl, C_1-4 alkoxy or C_1-4 haloalkoxy; and R¹, R², R³ and R⁴ are, independently, hydrogen, C_1-8 alkyl, C_1-8 haloalkyl, C_1-8 alkoxy, C_1-8 haloalkoxy, halogen, nitro, COR⁷, NR⁵R⁶, benzyl or phenyl (wherein benzyl or phenyl are optionally substituted by halogen, C_1-4 alkyl, C_1-4 haloalkyl, C_1-4 alkoxy, C_1-4 haloalkoxy or NR⁵R⁶); R¹ and R² or R² and R³ may join together to form a ring, the ring being optionally substituted by halogen, C_1-4 alkyl, C_1-4 haloalkyl, C_1-4 alkoxy, C_1-4 haloalkoxy or nitro; and R⁵, R⁶ and R⁷ are independently hydrogen or C_1-4 alkyl; provided that at least one of R¹ and R⁴ is hydrogen.

Alkyl, alkoxy and alkylthio groups are straight or branched chain and, for example, methyl, ethyl, n-propyl, iso-propyl, n-butyl or tert-butyl.

Halogen is fluorine, chlorine, bromine or iodine.

Alkenyl is, for example, vinyl or allyl. Cycloalkyl is, for example, cyclopropyl, cyclopentyl or cyclohexyl.

In one aspect the present invention provides a compound of formula (I) wherein A¹ and A² are, independently, phenyl optionally substituted by halogen, C_1-4 alkyl, or C_1-4 haloalkyl.

In another aspect the present invention provides a compound of formula (I) wherein

A¹ and A² are both unsubstituted phenyl.

In yet another aspect the present invention provides a compound of formula (I) wherein R is C_1-4 alkyl (especially methyl).

When R¹ and R² or R² and R³ join to form a ring the ring formed is carbocyclic or heterocyclic (preferably comprising 1, 2 or 3 heteroatoms independently selected from nitrogen, oxygen and sulphur) and is, optionally, aromatic. The ring is preferably a 5- or 6- membered ring. For example, R¹ and R² or R² and R³, together with the ring to which they are attached, may join to form a benzene, cyclohexane, pyridine or imidazole ring.

In another aspect the present invention provides a compound of formula (I) wherein R¹, R², R³ and R⁴ are, independently, hydrogen, C_1-8 alkyl, C_1-8 haloalkyl, halogen, COR⁷ or phenyl; R¹ and R² or R² and R³ may join together to form a ring, the ring being optionally substituted by halogen, C_1-4 alkyl, C_1-4 haloalkyl or nitro; provided that at least one of R¹ and R⁴ is hydrogen.

In yet another aspect the present invention provides a compound of formula (I) wherein R is C_1-4 alkyl (especially methyl or ethyl), C_2-4 alkenyl (especially vinyl), phenyl or C_{3- 6} cycloalkyl (especially cyclopropyl); A¹ and A² are both phenyl (optionally substituted with halogen (especially fluorine) or C_1-4 alkyl (especially methyl)), 2-thienyl or 3-furanyl; R¹, R², R³ and R⁴ are, independently, hydrogen, halogen (especially chlorine or bromine), C_1-4 alkyl (especially methyl or ethyl), NO₂, NH₂, N(CH₃)₂, C_1-4 haloalkyl (especially trifluoromethyl), benzyl or COR⁷ (wherein R⁷ is C_1-4 alkyl (especially methyl)); or R¹ and R² join to form a ring (R¹ and R² especially join to form the group C(CH₃)=CH-C(CH₃)=N); or R² and R³ join to form a ring (R² and R³ especially join to form the group CH₂CH₂CH₂CH₂, CHCHCHCH, CHCHCClCH, CHCClCHCH, CHCHC(NO₂)CH or CHC(NO₂)CHCH).

In a further aspect the present invention provides a compound of formula (I) wherein R is C_1-4 alkyl (especially methyl or ethyl), C_2-4 alkenyl (especially vinyl), phenyl or C₃-6 cycloalkyl (especially cyclopropyl); A¹ and A² are both phenyl (optionally substituted with halogen (especially fluorine) or C_1-4 alkyl (especially methyl)), 2-thienyl or 3-furanyl; R¹, R², R³ and R⁴ are, independently, hydrogen, halogen (especially chlorine or bromine), C_1-4 alkyl (especially methyl or ethyl), NO₂, C_1-4 haloalkyl (especially trifluoromethyl), benzyl or COR⁷ (wherein R⁷ is C_1-4 alkyl (especially methyl)); or R¹ and R² form a ring (R¹ and R² especially join to form the group C(CH₃)=CH-C(CH₃)=N); or R² and R³ form a ring (R² and R³ especially join to form the group CH₂CH₂CH₂CH₂, CHCHCHCH, CHCHCCICH, CHCHC(NO₂)CH or CHC(NO₂)CHCH).

In a still further aspect the present invention provides a compound of formula (I) wherein R is C_1-4 alkyl (especially methyl); A¹ and A² are both unsubstituted phenyl; R¹ is hydrogen, C_1-4 alkyl (especially methyl), phenyl or COR⁷; R², R³ and R⁴ are, independently, hydrogen, Cn alkyl (especially methyl), halogen (especially bromine), phenyl or COR⁷; provided that at least one of R¹ or R⁴ is hydrogen; and R⁷ is C_1-4 alkyl (especially methyl).

Examples of compounds of formula (I) are provided in Table I. Throughout TABLE I the following abbreviations are used:

Me = methyl Et = ethyl t-Bu = tert-butyl Ph = phenyl

A compound of formula (I) can be prepared by reacting a compound of formula (II):

wherein A¹ and A² are as defined above, with a Grignard reagent of formula RMgX, wherein R is as defined above and X is chlorine, bromine or iodine, and reacting the product formed with a compound of formula (III):

wherein R¹ , R² , R³, and R⁴ are as defined above. It is preferred that the reaction of RMgX with a compound of formula (II) is carried out at a temperature in the range -30 to 20°C (such as about O°C). It is preferred that this preparation is carried out in a suitable solvent, such as an ether (for example tetrahydrofuran or diethyl ether).

Alternatively a compound of formula (I) can be prepared by reacting a compound of formula (IV):

wherein R, A¹ and A² are as defined above, with a compound of formula (III) as defined above. It is preferred that this process is carried out at room temperature and in the presence of a solvent (such as an ether, for example diethyl ether).

Alternatively a compound of formula (I) can be prepared by reacting a compound of formula (V):

wherein R, A¹ and A² are as defined above, with a compound of formula (III) (as hereinbefore described) in a suitable solvent (such as a chlorinated solvent, for example dichloromethane) and at a suitable temperature (for example ambient temperature).

A compound of formula (V) can be prepared by reacting a compound of formula (II)

(as hereinbefore described) with a Grignard reagent of formula RMgX (as hereinbefore described), and reacting the product formed with ammonia and ammonium chloride solution sequentially. Alternatively a compound of formula (I) can be prepared by reacting a compound of formula (VI):

wherein A¹ and A² are as defined above and R* is C_1-4 alkoxy, with a Grignard reagent of formula RMgX (as hereinbefore described), and reacting the product formed with a compound of formula (III) (as hereinbefore described). It is preferred that the reaction of RMgX with a compound of formula (VI) is carried out at a temperature in the range -30 to 20°C (such as O°C). It is preferred that this preparation is carried out in a suitable solvent- such as an ether (for example tetrahydrofuran or diethyl ether).

A compound of formula (VI) can be prepared by reacting a tri( C_1-4 alkyl)borate with a

Grignard reagent A¹MgX or sequential addition of Grignard reagents A¹MgX and A²MgX, wherein A¹, A² and X are as defined above. It is preferred that this reaction is carried out at a temperature in the range -30 to 20°C (such as about O°C) and in a suitable solvent, such as an ether (for example tetrahydrofuran or diethyl ether).

Alternatively a compound of formula (VI) can be prepared by deprotonating a suitable phenyl, thiopheπe or furan compound using an alkyl lithium (such as n-butyl lithium), and reacting the product with a tri( C_1-4 alkyl)borate. It is preferred that this reaction is carried out at a temperature in the range -80 to 10°C (especially -80 to 0°C), and that it is conducted in a suitable solvent (such as tetrahydrofuran).

Compounds of formula (I) can be purified using standard procedures (such as crystallisation, trituration or high pressure liquid chromatography).

Compounds of formulae (II), (III), (IV), (V) and (VI) and Grignard reagents of formula RMgX are either known in the art or can be made by adaptation of standard literature procedures or by methods hereinbefore described.

In a further aspect the present invention provides processes, as hereinbefore described, for preparing the compounds of formula (I).

The compounds of formula (I) are active fungicides and may be used to control one or more of the following pathogens: Pyricularia oryzae on rice and wheat and other Pyricularia spp. on other hosts; Puccinia recondita, Puccinia striiformis and other rusts on wheat, Puccinia hordei, Puccinia striiformis and other rusts on barley, and rusts on other hosts e.g. turf, rye, coffee, pears, apples, peanuts, sugar beet, vegetables and ornamental plants; Erysiphe graminis (powdery mildew) on barley, wheat, rye and turf and other powdery mildews on various hosts such as Sphaerotheca macularis on hops, Sphaerotheca fuliginea on cucurbits (e.g. cucumber), Podosphaera leucotricha on apple and Uncinula necator on vines; Cochliobolus spp., Helminthosporium spp., Drechslera spp. (Pyrenophora spp.), Rhynchosporium spp., Septoria spp. (including Mycosphaerella graminicola and

Leptosphaeria nodorum), Pseudocercosporella herpotrichoides and Gaeumannomyces graminis on cereals (e.g. wheat, barley, rye), turf and other hosts; Cercospora arachidicola and Cercospoήdium personatum on peanuts and other Cercospora species on other hosts, for example, sugar beet, bananas, soya beans and rice; Botrytis cinerea (grey mould) on tomatoes, strawberries, vegetables, vines and other hosts and other Botrytis spp. on other hosts; Alternaria spp. on vegetables (e.g. cucumber), oil-seed rape, apples, tomatoes, cereals (e.g. wheat) and other hosts; Venturia spp. (including Venturia inaequalis (scab)) on apples, pears, stone fruit, tree nuts and other hosts; Cladosporium spp. on a range of hosts including cereals (e.g. wheat); Monilinia spp. on stone fruit, tree nuts and other hosts; Didymella spp. on tomatoes, turf, wheat and other hosts; Phoma spp. on oil-seed rape, turf, rice, potatoes, wheat and other hosts; Aspergillus spp. and Aureobasidium spp. on wheat, lumber and other hosts; Ascochyta spp. on peas, wheat, barley and other hosts; Plasmopara viticola on vines; other downy mildews such as Bremia lactucae on lettuce, Peronospora spp. on soybeans, tobacco, onions and other hosts, Pseudoperonospora humuli on hops and

Pseudoperonospora cubensis on cucurbits; Pythium spp. (including Pythium ultimum) on turf and other hosts; Phytophthora infestans on potatoes and tomatoes and other Phytophthora spp. on vegetables, strawberries, avocado, pepper, ornamentals, tobacco, cocoa and other hosts; Thanatephorus cucumeris on rice and turf and other Rhizoctonia species on various hosts such as wheat and barley, vegetables, cotton and turf; Sclerotinia spp. on turf, peanuts, oil-seed rape and other hosts; Sclerotium spp. on turf, peanuts and other hosts;

Colletotrichum spp. on a range of hosts including turf, coffee and vegetables; Laetisaria fuciformis on turf; Mycosphaerella spp. on banana, peanut, citrus, pecan, papaya and other hosts; Diaporthe spp. on citrus, soybean, melon, pear, lupin and other hosts; Elsinoe spp. on citrus, vines, olives, pecans, roses and other hosts; Pyrenopeziza spp. on oil-seed rape and other hosts; Oncobasidium theobromae on cocoa causing vascular streak dieback; Fusarium spp., Typhula spp., Microdochium nivale, Ustilago spp., Urocystis spp., Tilletia spp., and Claviceps purpurea on a variety of hosts but particularly wheat, barley, turf and maize;

Ramularia spp. on sugar beet and other hosts; post-harvest diseases particularly of fruit (e.g. Pencillium digitatum and P. italicum and Trichoderma viride on oranges, Colletotrichum musae and Gloeosporium musarum on bananas and Botrytis cinerea on grapes); other pathogens on vines, notably Eutypa lata, Guignardia bidwellii, Phellinus igniarus,

Phomopsis viticola, Pseudopezicula tracheiphila and Stereum hirsutum; other pathogens on lumber, notably Cephaloascus fragrans, Ceratocysris spp., Ophiostoma piceae, Penicilliwn spp., Trichoderma pseudokoningii, Trichoderma viride, Trichoderma harzianum, Aspergillus niger, Leptographium lindbergi and Aureobasidium pullulans; and fungal vectors of viral diseases e.g. Polymyxa graminis on cereals as the vector of barley yellow mosaic virus (BYMV).

Further, some of the compounds may be useful as seed dressings against pathogens including Fusarium spp., Septoria spp., Tilletia spp., (e.g. bunt, a seed-bome disease of wheat), Ustilago spp. and Helminthosporium spp. on cereals, Rhizoctonia solani on cotton and Pyricularia oryzae on rice. In particular, some of the compounds show good eradicant activity against Pythium ultimum.

The compounds may move acropetally/locally in plant tissue. Moreover, the compounds may be volatile enough to be active in the vapour phase against fungi on the plant.

The invention therefore provides a method of combating fungi which comprises applying to a plant, to a seed of a plant or to the locus of the plant or seed a fungicidally effective amount of a compound as hereinbefore defined, or a composition containing the same.

The compounds may be used directly for agricultural purposes but are more

conveniently formulated into compositions using a carrier or diluent. The invention thus provides fungicidal compositions comprising a compound as hereinbefore defined and an acceptable carrier or diluent therefor. It is preferred that all compositions, both solid and liquid formulations, comprise 0.0001 to 95%, more preferably 1 to 85%, for example 1 to 25% or 25 to 60%, of a compound as hereinbefore defined.

When applied to the foliage of plants, the compounds of the invention are applied at rates of 0.1g to 10kg, preferably lg to 8kg, more preferably lOg to 4kg, of active ingredient (invention compound) per hectare. When used as seed dressings, the compounds of the invention are used at rates of 0.0001g (for example 0.001g or 0.05g) to lOg, preferably 0.005g to 8g, more preferably 0.005g to 4g, of active ingredient (invention compound) per kilogram of seed.

The compounds can be applied in a number of ways. For example, they can be applied, formulated or unformulated, directly to the foliage of a plant, to seeds or to other medium in which plants are growing or are to be planted, or they can be sprayed on, dusted on or applied as a cream or paste formulation, or they can be applied as a vapour or as slow release granules.

Application can be to any part of the plant including the foliage, stems, branches or roots, or to soil surrounding the roots, or to the seed before it is planted, or to the soil generally, to paddy water or to hydroponic culture systems. The invention compounds may also be injected into plants or sprayed onto vegetation using electrodynamic spraying techniques or other low volume methods, or applied by land or aerial irrigation systems.

The term "plant" as used herein includes seedlings, bushes and trees. Furthermore, the fungicidal method of the invention includes preventative, protectant, prophylactic, systemic and eradicant treatments.

The compounds are preferably used for agricultural and horticultural purposes in the form of a composition. The type of composition used in any instance will depend upon the particular purpose envisaged.

The compositions may be in the form of dustable powders or granules comprising the active ingredient (invention compound) and a solid diluent or carrier, for example, fillers such as kaolin, bentonite, kieselguhr, dolomite, calcium carbonate, talc, powdered magnesia, fuller's earth, gypsum, diatomaceous earth and china clay. Such granules can be preformed granules suitable for application to the soil without further treatment. These granules can be made either by impregnating pellets of filler with the active ingredient or by pelleting a mixture of the active ingredient and powdered filler. Compositions for dressing seed may include an agent (for example, a mineral oil) for assisting the adhesion of the composition to the seed; alternatively the active ingredient can be formulated for seed dressing purposes using an organic solvent (for example, N-methylpyrrolidone, propylene glycol or

N,N-dimethylformamide). The compositions may also be in the form of water dispersible powders or water dispersible granules comprising wetting or dispersing agents to facilitate the dispersion in liquids. The powders and granules may also contain fillers and suspending agents.

The compositions may also be in the form of soluble powders or granules, or in the form of solutions in polar solvents.

Soluble powders may be prepared by mixing the active ingredient with a water-soluble salt such as sodium bicarbonate, sodium carbonate, magnesium sulphate or a polysaccharide, and a wetting or dispersing agent to improve water dispersibility/solubility. The mixture may then be ground to a fine powder. Similar compositions may also be granulated to form water-soluble granules. Solutions may be prepared by dissolving the active ingredient in polar solvents such as ketones, alcohols and glycol ethers. These solutions may contain surface active agents to improve water dilution and prevent crystallisation in a spray tank.

Emulsifiable concentrates or emulsions may be prepared by dissolving the active ingredient in an organic solvent optionally containing a wetting or emulsifying agent and then adding the mixture to water which may also contain a wetting or emulsifying agent. Suitable organic solvents are aromatic solvents such as alkylbenzenes and alkylnaphthalenes, ketones such as cyclohexanone and methylcyclohexanone, chlorinated hydrocarbons such as chlorobenzene and trichlorethane, and alcohols such as benzyl alcohol, furfuryl alcohol, butanol and glycol ethers.

Aqueous suspension concentrates of largely insoluble solids may be prepared by ball or bead milling with a dispersing agent with a suspending agent included to stop the solid settling.

Compositions to be used as sprays may be in the form of aerosols wherein the formulation is held in a container under pressure of a propellant, e.g. fluorotrichloromethane or dichlorodifluoromethane.

The invention compounds can be mixed in the dry state with a pyrotechnic mixture to form a composition suitable for generating in enclosed spaces a smoke containing the compounds.

Alternatively, the compounds may be used in micro-encapsulated form. They may also be formulated in biodegradable polymeric formulations to obtain a slow, controlled release of the active substance. By including suitable additives, for example additives for improving the uptake, distribution, adhesive power and resistance to rain on treated surfaces, the different compositions can be better adapted for various utilities. Other additives may be included to improve the biological efficacy of the various formulations. Such additives can be surface active materials to improve the wetting and retention on surfaces treated with the formulation and also the uptake and mobility of the active material, or additionally can include oil based spray additives, for example, certain mineral oil and natural plant oil (such as soya bean and rape seed oil) additives, or blends of them with other adjuvants.

The invention compounds can be used as mixtures with fertilisers (e.g. nitrogen-, potassium- or phosphorus-containing fertilisers). Compositions comprising only granules of fertiliser incorporating, for example coated with, a compound of formula (I) are preferred. Such granules suitably contain up to 25% by weight of the compound. The invention therefore also provides a fertiliser composition comprising a fertiliser and the compound of formula (I).

Water dispersible powders, emulsifiable concentrates and suspension concentrates will normally contain surfactants, e.g. a wetting agent, dispersing agent, emulsifying agent or suspending agent. These agents can be cationic, anionic or non-ionic agents.

Suitable cationic agents are quaternary ammonium compounds, for example, cetyltrimethylammonium bromide. Suitable anionic agents are soaps, salts of aliphatic monoesters of sulphuric acid (for example, sodium lauryl sulphate), and salts of sulphonated aromatic compounds (for example, sodium dodecylbenzenesulphonate, sodium, calcium or ammonium lignosulphonate, butylnaphthalene sulphonate, and a mixture of sodium

diisopropyl- and triisopropylnaphthalene sulphonates).

Suitable non-ionic agents are the condensation products of ethylene oxide with fatty alcohols such as oleyl or cetyl alcohol, or with alkyl phenols such as octyl- or nonylphenol and octylcresol. Other non-ionic agents are the partial esters derived from long chain fatty acids and hexitol anhydrides, alkyl glucosides, polysaccharides and the lecithins and the

condensation products of the said partial esters with ethylene oxide. Suitable suspending agents are hydrophilic colloids (for example, polyvinylpyrrolidone and sodium

carboxymethylcellulose), and swelling clays such as bentonite or attapulgite. Compositions for use as aqueous dispersions or emulsions are generally supplied in the form of a concentrate containing a high proportion of the active ingredient, the concentrate being diluted with water before use. these concentrates should preferably be able to withstand storage for prolonged periods and after such storage be capable of dilution with water in order to form aqueous preparations which remain homogeneous for a sufficient time to enable them to be applied by conventional spray equipment. The concentrates may conveniently contain up to 95%, suitably 1-85%, for example 1-25% or 25-60%, by weight of the active ingredient. After dilution to form aqueous preparations, such preparations may contain varying amounts of the active ingredient depending upon the intended purpose, but an aqueous preparation containing 0.0001 to 10%, for example 0.005 to 10%, by weight of active ingredient may be used.

The compositions of this invention may contain other compounds having biological activity, e.g. compounds having similar or complementary fungicidal activity or which possess plant growth regulating, herbicidal or insecticidal activity.

By including another fungicide, the resulting composition can have a broader spectrum of activity or a greater level of intrinsic activity than the compound of formula (I) alone.

Further the other fungicide can have a synergistic effect on the fungicidal activity of the compound of formula (I). Examples of fungicidal compounds which may be included in the composition of the invention are (RS)-1-aminopropylphosphonic acid, (RS)- 4-(4-chlorophenyl)-2-phenyl-2-(1H-1,2,4-triazoI-1-ylmethyl)butyronitrile, (Z)-N-but-2-enyloxymethyl-2-chloro-2',6'-diethylacetanilide, 1-(2-cyano-2-methoxyiminoacetyl)-3-ethyl urea, 4-(2,2-difluoro-1,3-benzodioxol-4-yl)pyrrole-3-carbonitrile, 4-bromo-2-cyano-N,N-dimethyl-6-trifluoromethylbenzimidazole-1-sulphonamide, 5-ethyl-5,8-dihydro-8-oxo

(1,3)-dioxol-(4,5-g)quinoline-7-carboxylic acid, α-[N-(3-chloro-2,6-xylyl)-2-methoxy¬acetamidoj-γ-butyrolactone, N-(2-methoxy-5-pyridyl)-cyclopropane carboxamide, alanycarb, aldimorph, ampropylfos, anilazine, azaconazole, BAS 490F, benalaxyl, benomyl, biloxazol, binapaciyl, bitertanol, blasticidin S, bromuconazole, bupirimate, butenachlor, buthiobate, captafol, captan, carbendazim, carbendazim chlorhydrate, carboxin, chinomethionate, chlσrbenzthiazone, chloroneb, chlorothalonil, chlorozolinate, clozylacon, copper containing compounds such as copper oxychloride, copper oxyquinolate, copper sulphate, copper tallate, and Bordeaux mixture, cycloheximide, cymoxanil, cyproconazole, cyprofuram, debacarb, di-2-pyridyl disulphide 1,1'-dioxide, dichlofluanid, dichlone, diclobutrazol, diclomezine, dicloran, didecyl dimethyl ammonium chloride, diethofencarb, difenoconazole,

0,0-di-iso-propyl-S-benzyl thiophosphate, dimefluazole, dimetconazole, dimethomorph, dimethirimol, diniconazole, dinocap, dipyrithione, ditalimfos, dithianon, dodemorph, dodine, doguadine, edifenphos, epoxiconazole, etaconazole, ethirimol, ethoxyquin, ethyl

(Z)-N-benzyl-N-([methyl(methyl-thioethylideneamino-oxycarbonyl)amino]thio)-β-alaninate, etridiazole, fenaminosulph, fenapanil, fenarimol, fenbuconazole, fenfuram, fenpiclonil, fenpropidin, fenpropimorph, fentin acetate, fentin hydroxide, ferbam, ferimzone, fluazinam, fludioxonil, fluoroimide, fluquinconazole, flusilazole, flutolanil, flutriafol, folpet, fuberidazole, furalaxyl, furametpyr, furconazole-cis, guazatine, hexaconazole, hydroxyisoxazole, hymexazole, ICIA5504, imazalil, imibenconazole, ipconazole, iprobenfos, iprodione, isopropanyl butyl carbamate, isoprothiolane, kasugamycin, mancozeb, maneb, mepanipyrim, mepronil, metalaxyl, metconazole, methfuroxam, metiram, metiram-zinc, metsulfovax, myclobutanil, ΝTΝ0301, neoasozin, nickel dimethyldithiocarbamate, nitrothal-isopropyl, nuarimol, ofurace, organomercury compounds, oxadixyl, oxolinic acid, oxycarboxin, pefurazoate, penconazole, pencycuron, phenazin oxide, phosetyl-Al, phosphorus acids, phthalide, polyoxin D, polyram, probenazole, prochloraz, procymidone, propamocarb, propamocarb hydrochloride, propiconazole, propineb, propionic acid, prothiocarb, pyracarbolid, pyrazophos, pyrifenox, pyrimethanil, pyroquilon, pyroxyfur, pyrrolnitrin, quaternary ammonium compounds, quinconazole, quinomethionate, quintozene, rabenazole, sodium pentachlorophenate, streptomycin, sulphur, tebuconazole, techlofthalam, tecnazene, tetraconazole, thiabendazole, thicyofen, thifluzamide, 2-(thiocyanomethylthio)benzothiazole, thiophanatemethyl, thiram, timibenconazole, tolclofos-methyl, tolylfluanid, triacetate salt of 1, 1'-iminodi(octamethylene)diguanidine, triadimefon, triadimenol, triazbutyl, triazoxide, tricyclazole, tridemorph, triforine, triflumizole, triticonazole, validamycin A, vapam, vinclozolin, XRD-563, zineb and ziram. The compounds of formula (I) can be mixed with soil, peat or other rooting media for the protection of plants against seed-borne, soil-borne or foliar fungal diseases.

The compounds of formula (I) may also be used to combat and control infestations of insect pests and also other invertebrate pests, for example, acarine pests. The insect and acarine pests which may be combated and controlled by the use of the invention compounds include those pests associated with agriculture (which term includes the growing of crops for food and fibre products), horticulture and animal husbandry, forestry, the storage of products of vegetable origin, such as fruit, grain and timber, and also those pests associated with the transmission of diseases of man and animals.

In order to apply the compounds to the locus of the pests they are usually formulated into compositions which include in addition to the insecticidally active ingredient or ingredients of formula (I) suitable inert diluent or carrier materials, and/or surface active agents. The compositions may also comprise another pesticidal material, for example another insecticide or acaricide, or a fungicide, or may also comprise an insecticide synergist, such as for example dodecyl imidazole, safroxan, or piperonyl butoxide.

The compositions may be in the form of dusting powders wherein the active ingredient is mixed with a solid diluent or carrier, for example kaolin, bentonite, kieselguhr, or talc, or they may be in the form of granules, wherein the active ingredient is absorbed in a porous granular material for example pumice.

Alternatively the compositions may be in the form of baits wherein the active ingredient is mixed with a nutrient carrier for example sucrose, yeast, malt extract, cereal or cereal products and optionally an attractant such as a pheromone or pheromone analogue.

Alternatively the compositions may be in the form of liquid preparations to be used as dips or sprays, which are generally aqueous dispersions or emulsions of the active ingredient in the presence of one or more known wetting agents, dispersing agents or emulsifying agents (surface active agents) of the type described above for the fungicidal compositions.

The insecticidal compositions may be prepared by dissolving the active ingredient in a suitable solvent, for example, a ketonic solvent such as diacetone alcohol, or an aromatic solvent such as trimethylbenzene and adding the mixture so obtained to water which may contain one or more known wetting, dispersing or emulsifying agents.

Other suitable organic solvents are dimethyl formamide, ethylene dichloride, isopropyl alcohol, propylene glycol and other glycols, diacetone alcohol, toluene, kerosene, white oil, methylnaphthalene, xylenes and trichloroethylene, N-methyl-2- pyrrolidone and

tetrahydrofurfuryl alcohol (THFA).

The insecticidal compositions which are to be used in the form of aqueous dispersions or emulsions are generally supplied in the form of a concentrate containing a high proportion of the active ingredient or ingredients, the said concentrate to be diluted with water before use. These concentrates are often required to withstand storage for prolonged periods and after such storage, to be capable of dilution with water to form aqueous preparations which remain homogeneous for a sufficient time to enable them to be applied by conventional spray equipment. The concentrates may contain 10-85% by weight of the active ingredient or ingredients. When diluted to form aqueous preparations such preparations may contain varying amounts of the active ingredient depending upon the purpose for which they are to be used. For agricultural or horticultural purposes, an aqueous preparation containing between 0.0001% and 0.1% by weight of the active ingredient (approximately equivalent to from 5-2000g/ha) is particularly useful.

In use the insecticidal compositions are applied to the pests, to the locus of the pests, to the habitat of the pests, to growing plants liable to infestation by the pests, or, where there is systemic uptake by plants, to the soil surrounding plants liable to infestation, by any of the known means of applying pesticidal compositions, for example, by dusting or spraying.

The compounds of the invention may be the sole active ingredient of the insecticidal composition or they may be admixed with one or more additional active ingredients such as insecticides, insecticide synergists, herbicides, fungicides or plant growth regulators where appropriate.

Suitable additional active ingredients for inclusion in admixture with the compounds of the invention may be compounds which will broaden the spectrum of activity of the compounds of the invention or increase their persistence in the location of the pest. They may synergise the activity of the compound of the invention or complement the activity for example by increasing the speed of effect, improving knockdown or overcoming repellency. Additionally multi-component mixtures of this type may help to overcome or prevent the development of resistance to individual components.

The particular insecticide, herbicide or fungicide included in the mixture will depend upon its intended utility and the type of complementary action required. Examples of suitable insecticides include the following:

• Pyrethroids such as permethrin, esfenvalerate, deltamethrin, cyhalothrin in particular lambda-cyhalothrin, cypermethrin, alpha cypermethrin, bifenthrin, fenpropathrin, cyfluthrin, tefluthrin, fish safe pyrethroids for example ethofenprox, natural pyrethrin. tetramethrin, s-bioallethrin, fenfluthrin, prallethrin, or

5-benzyl-3-furylmethyl-(E)-(1R,3S)-2,2-dimethyl-3-(2-oxothiolan-3-ylidenemethyl) cyclopropane carboxylate;

• Organophosphates such as profenofos, sulprofos, methyl parathion, azinphos-methyl, demeton-s-methyl, heptenophos, thiometon, fenamiphos, monocrotophos, triazophos, methamidophos, dimethoate, phosphamidon, malathion, chloropyrifos, phosalone, fensulfothion, fonofos, phorate, phoxim, pirimiphos-methyl, fenitrothion or diazinon;

• Carbamates (including aryl carbamates) such as pirimicarb, cloethocarb, carbofuran, ethiofencarb, aldicarb, thiofurox, carbosulfan, bendiocarb, fenobucarb, propoxur or oxamyl;

• Benzoyl ureas such as triflumuron, or chlorfluazuron;

• Organic tin compounds such as cyhexatin, fenbutatin oxide, or azocyclotin;

• Macrolides such as avermectins or milbemycins, for example such as abamectin,

ivermectin, and milbemycin;

• Hormones such as pheromones;

• Organochlorine compounds such as benzene hexachloride, DDT, chlordane or dieldrin; or

• Amidines, such as chlordimeform or amitraz.

In addition to the major chemical classes of insecticide listed above, other insecticides having particular targets may be employed in the mixture if appropriate for the intended utility of the mixture. For instance selective insecticides for particular crops, for example stemborer specific insecticides for use in rice such as cartap or buprofezin can be employed.

Alternatively insecticides specific for particular insect species/stages for example ovo-larvicides such as clofentezine, flubenzimine, hexythiazox and tetradifon, acaricides such as dicofol, propargite, bromopropylate, chlorobenzilate, or growth regulators such as hydramethylnon, cyromazine, methoprene, hydroprcne, chlorfluazuron and diflubenzuron may also be included in the compositions.

Examples of suitable insecticide synergists for use in the compositions include piperonyl butoxide, sesamex, and dodecyl imidazole.

Suitable herbicides, fungicides and plant-growth regulators for inclusion in the compositions will depend upon the intended target and the effect required. An example of a rice selective herbicide which can be included is propanil, an example of a plant growth regulator for use in cotton is "Pix", and examples of fungicides for use in rice include blasticides such as blasticidin-S.

The ratio of the compound of the invention to the other active ingredient in the composition will depend upon a number of factors including type of target, effect required from the mixture etc.

However in general, the additional active ingredient of the composition will be applied at about the rate as it is usually employed, or at a slightly lower rate if synergism occurs.

The compounds of formula (I) and insecticidal compositions comprising them may also be active against organophosphate, pyrethroid or cyclodiene (for example lindane or dieldrin) resistant strains of public and animal health pests. They may be effective in combating both susceptible and resistant strains of the pests in their adult and immature stages of growth, and may be applied to the infested host animal by topical, oral or parenteral administration.

The compounds of formula (I) can be used to control one or more of the following micro-organisms: Aspergillus niger, Aureobasidium pullulans, Candida albicans,

Gliocladium roseum, Pencillium pinophylum, Bacillus subtilis, Escherichia coli,

Pseudomonas aeruginose or Staphylococcus aureus.

Systems in which micro-organisms cause problems include liquid, particularly aqueous, systems such as cooling water liquors, paper mill liquors, metal working fluids, geological drilling lubricants, polymer emulsions and especially surface coating compositions such as paints, varnishes and lacquers and more especially solid materials such as wood, plastics materials and leather. The compounds of formula (I) can be used as disinfectants (especially for solid surfaces). A compound of formula (I) can be included in such materials to provide an anti-microbial effect. The amount of the compound is typically in the range of 0.00001 to 2.0% preferably from 0.0001 to 1% and especially from 0.0002 to 0.5% by weight of the compound relative to the system to which it is added.

The invention therefore provides a method of combating the growth of micro-organisms which comprises applying a compound of formula (I) to a surface or providing a compound of formula (I) to the locus of a surface, said surface being susceptible to micro-organism growth. When used to control micro-organisms, a compound of formula (I) may be used directly or formulated in a composition comprising a carrier or diluent.

In such compositions the carrier is generally selected so that the composition is compatible with the medium to be protected. Thus, for example, if the medium to be protected is a solvent-based paint, lacquer or varnish the carrier is preferably a solvent especially a non-polar solvent such as white spirits.

If the medium to be protected is a plastics material, the carrier is preferably a plasticiser or stabiliser typically used in the fabrication of plastics articles such as

dioctylphthalate, dioctyladipate or epoxidised soya bean oil. If the medium to be protected is an aqueous medium, the carrier is preferably water or a water-miscible organic solvent or mixture thereof. Examples of suitable water-miscible organic solvents are acetic acid, N,N-dimethylformamide, dimethylsulphoxide, N-methyl-2-pyrrolidine, alcohols (such as ethanol or a glycol (such as ethylene glycol, propylene glycol or dipropylene glycol)) or lower C_1-4 alkyl carbitols (such as methyl carbitol). If the carrier is a solid, the composition may be a dry solid.

When used to protect paint-films, latices or plastics materials it is preferred that a compound of formula (I) is formulated in a composition including a carrier which is a plasticiser or stabiliser. Thus in a further aspect the present invention provides a biocidal composition comprising a biocidally effective amount of a compound of formula (I) and a biocidally acceptable carrier or diluent therefor. If the biocide composition is in the form of a suspension or emulsion, it preferably also contains a surface active agent to produce a stable dispersion or to maintain the non-continuous phase uniformly distributed throughout the continuous phase. Any surface active agent which does not adversely affect the biocidal activity of the compound of formula (I) may be used, such as those hereinbefore recited, for example alkylene oxide adducts of fatty alcohols, alkyl phenols, amines such as ethylene diamine or anionic surfactants such as adducts of naphthol sulphonates and formaldehyde.

The concentration of the compound of formula (I) in the biocide composition is preferably up to a level at which the biocide composition is stable under the conditions of storage or transportation and is preferably from 1 to 50%, especially from 5 to 30% and more especially from 10 to 20% by weight relative to the total weight of the biocide composition. The compound of formula (I) may be the only antimicrobial compound used to protect the medium or it may be used together with other compounds having antimicrobial activity. A mixture of anti-microbial compounds hereinafter referred to as a "biocide mixture" often has a broader anti-microbial spectrum and hence is more generally effective than the components of the mixture. The other antimicrobial compound or compounds may possess antibacterial, anti-fungal, anti-algal or other antimicrobial activity. The biocide mixture typically contains from 1 to 99% by weight, and preferably from 40 to 60% by weight, of a compound of formula (I) relative to the total weight of an antimicrobially active compound, in the biocide mixture.

Examples of other antimicrobial compounds which may be used, together with the compound of formula (I) are: quaternary ammonium compounds such as N,N-dimethyl-N-dodecyl-N-benzylammonium chloride, NN-dimethyl-N-octadecyl-N-(dimethylbenzyl)-ammonium chloride, N,N-dimethyl-N,N-didecylammonium chloride, N,N-dimethyl-N,N-didodecylammonium chloride, N,N,N-trimethyl-N-tetradecylammonium chloride, N-benzyl-N,N-dimethyl-N(C₁₂-C₁₈-alkyl)ammonium chloride, N-(dichlorobenzyl)-N,N-dimethyl-N-dodecylammonium chloride, N-hexadecylpyridinium chloride; N-hexadecylpyridinium bromide, N-hexadecyl-N,N,N-trimethylammonium bromide; N-dodecylpyridinium chloride, N-dodecylpyridinium bisulphate, N-benzyl-N-dodecyl-N,N-bis(beta-hydroxyethyl)ammonium chloride, N-dodecyl-N-benzyl-N,N-dimethylammonium chloride, N-benzyl-N,N-dimethyl-N-(C₁₂-C₁₈-alkyl)ammonium chloride, N-dodecyl-N,N-dimethyl-N-ethylammonium ethylsulphate, N-dodecyl-N,N-dimethyl-N-(1-naphthylmethyl)ammonium chloride, N-hexadecyl-N,N-dimethyl-N-benzylammonium chloride, N-dodecyl-N,N-dimethyl-N-benzylammonium chloride and 1-(3-chloroallyl)-3,5,7-triaza-1-azonia-adamantane chloride; urea derivatives such as 1,3-bis(hydroxymethyl)-5,5-d-methylhydantoin, bis(hydroxymethyl) urea, 3-(3,4-dichlorophenyl)-1,1-dimethylurea, 3-(4-isopropylphenyl)-1,1-dimethylurea, tetrakis(hydroxymethyl)acetylene diurea, l-(hydroxymethyl)-5,5-dimethylhydantoin and imidazolidinylurea; amino compounds such as 1,3-bis(2-ethylhexyl)-5-methyl-5-amino-hexahydropyrirnidine, hexamethylenetetramine, 1,3-bis(4-aminophenoxy)propane and 2-[(hydroxymethyl)amino]ethanol; imidazole derivatives such as 1-[2-(2,4-dichlorophenyl)-2-(2-propenyloxy)ethyl]-1H-imidazole, 2-(methoxycarbonylamino)benzimidazole, 1-decyl-3-dodecyl-2-methylimidazolium bromide and dodecylbis(1-decyl-2-methylimidazolium)dibromide; nitrile compounds such as 2-bromo-2- bromomethyl-glutaronitrile, 2-chloro-2-chloromethylglutaronitrile and 2,4,5,6-tetra- chloroisophthalodinitrile; thiocyanate derivatives such as methylene(bis)thiocyanate; tin compounds or complexes such as tributyltin oxide, chloride, naphthoate, benzoate or 2-hydroxybenzoate; isothiazolin-3-ones such as 4,5-trimethylene-4-isothiazolin-3-one, 2-methyl-4,5-trimethylene-4-isothiazolin-3-one, 2-methylisothiazolin-3-one, 5-chloro-2-methyIisothiazolin-3-one, benzisothiazolin-3-one, 2-methylbenzisothiazolin-3-one, 2-octylisothiazolin-3-one, 4,5-dichloro-2-octylisothiazolin-3-one, N-(2-ethylbutyl)benzisothiazolin-3-one and N-(n-hexyl)benzisothiazolin-3-one; thiazole derivatives such as 2-(thiocyanomethylthio)benzthiazole and mercaptobenzthiazole; nitro compounds such as tris(hydroxymethyl)nitromethane, 5-bromo-5-nitro-1,3-dioxane and 2-bromo-2-nitropropane-1,3-diol; iodine compounds such as iodopropynylbutylcarbamate and tri-iodoallyl alcohol; aldehydes derivatives such as glutaraldehyde (pentanedial), p-chlorophenyl-3-iodopropargyl hemiformal, formaldehyde and glyoxal; amides such as chloracetamide, N,N-bis(hydroxymethyl)chloracetamide, N-hydroxymethylchloracetamide and dithio-2,2-bis(benzmethylamide); guanidine derivatives such as poly(hexamethylenebiguanide) and 1,6-hexamethylene-bis[5-(4-chlorophenyl)biguanide]; imidazolium halides such as N,N-didecyl-2-methyIimidazolium bromide and 1,12-bis-(N-decyl-2-methylimidazolium)dodecyI dibromide; thiones such as 3,5-dimethyltetrahydro-1,2,5-2H-thiodiazine-2-thione; triazine derivatives such as hexahydrotriazine, 1,3,5-tri-(hydroxyethyl)-1,3,5-hexahydrotriazine, 6-chloro-2,4-diethylamino-s-triazine and 4-cyclopropylamino-2-methylthio-6-t-butylamino-s-triazine;

oxazolidine derivatives such as bis-oxazolidine; furan derivatives such as 2,5-dihydro-2,5-dialkoxy-2,5-dialkylfuran; carboxylic acids or salts or esters thereof such as sorbic acid and 4-hydroxybenzoic acid or their salts or esters; phenol derivatives such as 5-chloro-2-(2,4-dichlorophenoxy)phenol, thio-bis(4-chlorophenol) and 2-phenylphenol; sulphone derivatives such as diiodomethyl-p-tolyl sulphone, 2,3,5,6-tetrachloro-4-(methylsulphonyl)pyridine and hexachlorodimethyl sulphone; thioamides such as dimethyldithiocarbamate, ethylenebisdithiocarbamate and 2-mecaptopyridine-N-oxide or metal complexes thereof; and imides such as trict-loromethylmercaptophthalimide, fiuorodichloromethylmercaptophthalimide and tricWoromethylmercaptotetrahydrophthalimide.

The following Examples illustrate the invention. The following abbreviations are used throughout:

EXAMPLE 1

This Example illustrates the preparation of (1H-3,5-dimethyl-2-pyrazolyl)

(diphenyl)methylborane (Compound No. 1 in Table I).

Methylmagnesium bromide (3.0 M solution in diethyl ether; 20 ml, 60 mmol) was added to a solution of diphenylborinic acid ethanolamine ester (4.5 g, 20 mmol) in

tetrahydrofuran (60 ml) at ambient temperature. The resulting solution was stirred at ambient temperature under nitrogen for 2 hours. 3,5-Dimethylpyrazole (3.84 g, 40 mmol) was added and the reaction mixture stirred under nitrogen at ambient temperature for 19 hours. The solution was acidified by the addition of dilute hydrochloric acid, and the phases separated.

The aqueous phase was extracted with ethyl acetate and the combined organic phases dried and evaporated to leave a pale yellow oil which solidified on standing. This solid was suspended in hexane, then filtered and dried to yield the title compound as a cream solid (2.78 g); mp 146-148°C. Η NMR (CDC1₃ ): δ 9.48 (1H, br s), 7.17 (10H, m), 5.97 (1H, s), 2.10

(6H, br s), 0.55 (3H, s) ppm.

EXAMPLE 2

This Example illustrates the preparation of di(4-fluorophenyl)(1H-3,5-dimethyl-2- pyrazolyl)methylborane (Compound No. 721 in Table I).

To a stirred solution of tri-iso-propylborate (18.8g) in diethyl ether (200ml), under nitrogen and at 0°C (approximately) was added 4-fluorophenylmagnesium bromide (101ml of a 2.0M solution in diethyl ether) dropwise, not allowing the temperature to rise above 0°C. When the addition was complete, the mixture was stirred at 0°C for 2.5 hours and then warmed to room temperature over 30 minutes. Ethereal hydrogen chloride (4ml; 0.1825g/ml) was then added slowly to the mixture. The resulting mixture was filtered and the filtrate evaporated in vacuo to leave a brown oil and a solid. The mixture of oil and solid was treated with pentane, the pentane mixture was filtered under nitrogen, and the filtrate evaporated in vacuo to leave a mobile oil. The oil was distilled at 99°C and 0.9 mmHg to give wo-propyl di(4-fluorophenyl)borate as a colourless oil. To a stirred solution of iso-propyl di(4-fluorophenyl)borate (0.52g) in dry tetrahydrofuran (10ml) at -5°C under nitrogen, was added, dropwise, methylmagnesium bromide (0.67ml of a 3M solution in diethyl ether). The mixture was stirred at -5°C for 1 hour and then at room temperature for 1 hour. The mixture was cooled to -5°C and 2,4-dimethylpyrazole (192mg) was slowly added. The mixture was then allowed to stand at room temperature overnight.

The mixture was cooled to 5°C and saturated, aqueous ammonium chloride solution added cautiously until the white solid that formed initially dissolved. The resulting mixture was then extracted several times with ethyl acetate. The extracts were combined, washed with saturated brine, dried and then evaporated in vacuo to leave the title compound as a viscous oil (0.622g).

1H NMR: 67.18 & 6.87 (2 × m, 8H), 5.86(s,1H), 2.10(brs, 6H), 0.19(s,3H)ppm.

EXAMPLE 3

This Example illustrates the preparation of (1H-2-pyrazolyl)(diphenyl)methylborane (Compound No.3 in Table I).

Methylmagnesium bromide (49.8ml of a 2.7M solution in diethyl ether) was added to a stirred solution of diphenylborinic acid ethanolamine ester (10.0g) in dry tetrahydrofuran (150ml) at room temperature. A water bath was used to maintain the temperature at approximately room temperature. The resulting solution was stirred at room temperature for 2 hours. Ammonia gas was then bubbled into the solution, with vigorous stirring, for about 1.75 hours. The reaction mixture was allowed to stand for 4 days.

Saturated aqueous ammonium chloride solution (125ml) was added dropwise followed by water (20ml). The organic layer was separated, washed with saturated brine, dried and evaporated in vacuo to leave a waxy solid. This solid was stirred with chloroform (30ml) for 30 minutes and filtered. The residue was washed with a little cold chloroform and dried to leave the ammonia complex of (diphenyl)methylborane as a crystalline solid (5.82g). ¹H NMR: (DMSO) δ 7.18(dd, 4H), 6.98(t,4H), 6.85(m,2H), 4.96(brs,3H), 0.02(s,3H)ppm.

To a solution of the ammonia complex of (diphenyl)methylborane (0.2g) in dichloromethane (5ml) was added, with stirring, a solution of pyrazole (0.069g) in dichloromethane (5ml). The resulting mixture was stirred for 2.5 hours and then allowed to stand overnight. The mixture was filtered over magnesium sulphate and the filtrate evaporated in vacuo to leave the title compound (200mg) as a white solid.

EXAMPLE 4

This Example illustrates the preparation of (1H-3,5-dimethyl-2-pyrazolyl)

triphenylborane (Compound No. 193 in Table I).

A solution of 3,5-dimethylpyrazole (1.00g, 10.4mmol) and triphenylborane (2.52g, 10.4mmol) in diethyl ether (20ml) was stirred under nitrogen at ambient temperature for 4 hours and then allowed to stand overnight. The resultant white solid was filtered off, washed with diethylether and dried to provide the title compound (1.00g).

EXAMPLE 5

The compounds were tested against a variety of foliar fungal diseases of plants. The technique employed was as follows.

The plants were grown in John Innes Potting Compost (No 1 or 2) in 4 cm diameter minipots. The test compounds were formulated either by bead milling with aqueous

DISPERSOL T or as a solution in acetone or acetone/ethanol which was diluted to the required concentration immediately before use. The formulations (100 ppm active ingredient) were sprayed on to the foliage or applied to the roots of the plants in the soil. The sprays were applied to maximum retention and the root drenches to a final concentration equivalent to approximately 40 ppm a.i. in dry soil. TWEEN 20 was added to give a final concentration of 0.05% when the sprays were applied to cereals.

For most of the tests the compounds were applied to the soil (roots) or to the foliage (by spraying) one or two days before the plant was inoculated with the disease. Foliar pathogens were applied by spray as zoosporangial suspensions onto the leaves of test plants. After inoculation, the plants were put into an appropriate environment to allow infection to proceed and then incubated until the disease was ready for assessment. The period between inoculation and assessment varied from four to fourteen days according to the disease and environment

The disease level present (i.e. leaf area covered by actively sporulating disease) on each of the treated plants was recorded using the following assessment scale:

Each assessment was then expressed as a percentage of the level of disease present on the untreated control plants. This calculated value is referred to as a POCO (Percentage of Control) value. An example of a typical calculation is as follows:

Disease level on untreated control = 90

Disese level on treated plant = 30

This calculated POCO value is then rounded to the nearest of the values in the 9-point assessment scale shown above. In this particular example, the POCO value would be rounded to 30. If the calculated POCO falls exactly mid-way between two of the points, it is rounded to the lower of the two values.

The results are shown in Table II.

Unless stated otherwise, data represent activity following application as a combined foliar spray and root drench treatment at 100 ppm.

EXAMPLE 6

The compounds were tested against a variety of micro-organisms. The technique employed was as follows.

A bacterial inoculum consisted of 24 hour cultures of the organisms grown in Oxoid Nutrient broth, subcultured daily and incubated at 37°C.

Spore suspensions of each of the test micro-organisms were prepared in the following manner. To 250 ml conical flasks containing sporulating cultures of the micro-organisms, growing on Oxoid Malt extract agar, a number of sterile 3mm glass beads and approximately 50 ml of a sterile solution of TWEEN 80 in water were added. Each flask was swirled so that the beads removed the spores and the resulting suspension was poured into a sterile 100gm medical flat bottle containing approximately 50 ml of the sterile 0.01 % v/v solution of TWEEN 80. The suspension was storable for up to four weeks at 4°C. The compounds of formula (I) were tested against the micro-organisms listed in the footnote to Table III. The data presented in Table III show the minimum concentration required for complete control of each micro-organism.

EXAMPLE 7

The activity of compounds of formula (I) was determined using adult Tetranychus urticae strain G90.

French bean plants were selected with fully developed primary leaves. The growing points and leaf tips were removed, leaving 2 leaves per plant. Adult-infested leaves from a Tetranychus urticae strain G90 culture were placed on the leaves of the selected french beans. The plants were left at 25°C, 60% relative humidity, for a 16 hour photoperiod overnight.

Approximately 25 mL of a 7.5 g/L agar solution was added to 1½" squat pots and allowed to cooL Cut leaf discs from the infested french bean plants were placed, underside uppermost, on the agar on droplet of water. At least 20 mites were present on each disc. The pots were sprayed with a solution of a compound of formula (I) (solute 1:1 acetone:ethanol) at various rates. After a brief drying period each pot was covered with a ventilated lid and stored at 25°C, 60% relative humidity, for a 16 hour photoperiod. The pots were assessed three days after treatment and insect mortality scored. The following percentage mortality results for compounds of TABLE I were obtained:

Claims

1. A compound of formula (I)

wherein A¹ and A² are, independently, phenyl, furyl or thienyl each optionally substituted by halogen, C_1-4 alkyl, C_1-4 alkoxy, C_1-4 alkylthio, C_1-4 haloalkyl, C_1-4 haloalkoxy or C_1-4 haloalkylthio; R is C_1-4 alkyl, C_1-4 haloalkyl, C_2-4 alkenyl, C_2-4 haloalkenyl, C_3-7 cycloalkyl, C_3-7 cycloalkyl(C_1-4)alkyl, benzyl or phenyl, wherein benzyl and phenyl are optionally substituted by halogen, C_1-4 alkyl, C_1-4 haloalkyl, C_1-4 alkoxy or C_1-4 haloalkoxy; and R¹, R², R³ and R⁴ are, independently, hydrogen, C_1-8 alkyl, C_1-8 haloalkyl, C_1-8 alkoxy, C_1-8 haloalkoxy, halogen, nitro, COR⁷, NR⁵R⁶, benzyl or phenyl (wherein benzyl and phenyl are optionally substituted by halogen, C_{1- 4} alkyl, C_1-4 haloalkyl, C_1-4 alkoxy, C_1-4 haloalkoxy or NR⁵R⁶); R¹ and R² or R² and R³ may join together to form a ring, the ring being optionally substituted by halogen, C_1-4 alkyl, C_1-4 haloalkyl, C_1-4 alkoxy, C_1-4 haloalkoxy or nitro; and R⁵, R⁶ and R⁷ are independently hydrogen or C_1-4 alkyl; provided that at least one of R¹ and R⁴ is hydrogen.

2. A compound as claimed in claim 1 wherein R is C_1-4 alkyl.

3. A compound as claimed in claim 1 or 2 wherein A¹ and A² are both unsubstituted phenyl.

4. A compound as claimed in claim 1 wherein wherein R is C_1-4 alkyl, C_2-4 alkenyl, phenyl or C_3-6 cycloalkyl; A¹ and A² are both phenyl (optionally substituted with halogen or C_1-4 alkyl), 2-thienyl or 3-furanyl; R¹, R², R³ and R⁴ are, independently, hydrogen, halogen, C_1-4 alkyl, NO₂, NH₂, N(CH₃)₂, C_1-4 haloalkyl, benzyl or COR⁷ (wherein R⁷ is C_1-4 alkyl); or R¹ and R² or R² and R³ join to form a ring. A process for preparing a compound of formula (I), the process comprising:

i. reacting:

a) a compound of formula (V)

OR

b) the product produced by contacting a compound of formula (II)

with a Grignard reagent of formula RMgX,

OR

c) the product produced by contacting a compound of formula (VI)

with a Grignard reagent of formula RMgX,

OR

d) a compound of formula (IV)

with a compound of formula (III)

wherein R, A¹, A², R¹, R², R³ and R⁴ are as defined above, R* is C_1-4 alkoxy, and X is chlorine, bromine or iodine. 6. A fungicidal composition comprising a fungicidally effective amount of a compound according to claim 1 and a fungicidally acceptable carrier or diluent therefor. 7. A method of combating fungi which comprises applying to plants, to the seeds of plants or to the locus of the plants or seeds, a compound according to claim 1 or a composition according to claim 6. 8. A biocidal composition comprising a biocidally effective amount of a compound according to claim 1 and a biocidally acceptable carrier or diluent therefor. 9. A method of combating the growth of micro-organisms which comprises applying a compound of formula (I) or a composition according to claim 8 to a surface or providing a compound of formula (I) to the locus of a surface, said surface being susceptible to micro-organism growth.

10. An insecticidal, acaricidal, miticidal or nematicidal composition comprising an effective amount of a compound according to claim 1 and an acceptable carrier or diluent therefor. 11. A method of combating insect, acarine, mite or nematode pests which comprises applying to the locus of the pest, an effective amount of a compound according to claim 1 or a composition according to claim 10.