CS269982B2 - Insecticide and acaricide and method of active substances production - Google Patents

Abstract

Thiadiazole derivs. of formula (I), their salts and optical isomers are new: R1=H or 1-4C alkyl; R=H, 1-4C alkyl, alkoxy or alkylthio (all opt. substd. by 1-9 halo); halo; NO2; CN; or (all opt. substd.) phenyl, phenylalkyl, phenoxy, phenylthio or pyridyloxy; n=1-5. - Also new are intermediates of formula (IV).

Description

(57) The insecticidal and acaricidal composition is characterized in that it contains at least one optionally substituted 2-phenyl-5-pyridyl-4,5-dihydro-1,3,4-thiadiazole of the general formula I, in which r6 represents hydrogen or C 1 -C 4 -alkyl, R is C 1 -C 4 -alkyl, halogen, C 1 -C 4 -alkoxy or CF 3 and n is 0 to 2, or a salt thereof or an optically active isomer of a compound of formula (I) together with a carrier and / or other ingredients. A process for the preparation of the novel compounds of the formula I is further described by treating a compound of the formula ц with a compound of the formula III, then converting the optionally obtained compound of the formula I into its salt or separating into its optical isomers. The composition is used to combat pests that attack plants and animals.

26_9 9 82 (11) (13) 02 (52) Int. Cl. ⁴

A 01 N 43/82

The invention also relates to an insecticidal and acaricidal composition comprising, as active ingredient, novel, optionally substituted 2-phenyl-5-pyridyl-4,5-dihydro-1,3,4-thiadiazoles. their use as active ingredients in insecticidal and acaricidal agents ·

It has been found that the novel, optionally substituted 2-phenyl-5-pyridyl-4,5-dihydro-1,3,4-thiadiazoles of formula I

wherein n represents a hydrogen atom or an alkyl group having 1 to 4 carbon atoms,

R is C 1 -C 4 alkyl, halogen, C 1 -C 4 alkoxy or trifluoromethyl, and n is 0 to 2;

as well as its salts and optical isomers of the compounds of the formula I have excellent efficacy as insecticidal and acaricidally active compounds with good plant compatibility and low warm-blood toxicity.

Accordingly, it is an object of the present invention to provide an insecticidal and acaricidal composition comprising at least one optionally substituted 2-phenyl-6-pyridyl-4,5-dihydro-1,3,4-thiadiazole of the aforementioned and defined general formula. I or a salt thereof or an optically active isomer of this compound together with suitable carriers and / or other additives

Preferred are compounds of formula I wherein n is 1 or 2;

Of particular interest as active ingredients of the insecticidal and acaricidal compositions of the invention are compounds of formula (Ia)

(ia) in which

is hydrogen or alkyl having 1 to 4 carbon atoms, and R ₃ are independently hydrogen, halogen, alkyl of 1-4 carbon atoms, trifluoromethyl or alkoxy yne with 1 to 4 carbon atoms,

As well as salts of a compound of formula Ia, and in particular such a compound of formula Ia, in which

R ^ represents a hydrogen atom, a methyl group or an ethyl group,

R ₂ and R 8 are each independently hydrogen or halogen in the 2 and / or 4-position.

Preferred are, in addition to the compounds mentioned above, those compounds of the general formula (i) and (ii) and ( _t) in which R @ 1 and / or R @ 2 are hydrogen.

In view of their biological activity, those compounds of the formula I or Ia in which the pyridyl group is attached by its 3-position to the 5-position of the 4,5-dihydro-1,3,4-thiadiazole ring are of particular interest.

The active compounds which can be used in the insecticidal and acaricidal compositions according to the invention also include salts, in particular salts which are physiologically harmless to plants, of the compounds of the formulas I and Ia, respectively. Suitable salts with organic and inorganic acids are, for example, the following: chlorides, bromides, iodines, sulphates, hydrogen sulphates, chlorates, perchlorates, rhodanides, nitrates, phosphates, hydrogen phosphates, tetraflaoroborates, formates, acetates, trichloroacetates, trifluoroacetates, trifluoroacetates, trifluoroacetates malonates, succinates, small ones, tetrates or citrates.

The active substances which can be used further in the compositions according to the invention also include optical isoomers of the compounds of the general formulas I and Ia, respectively, which can be obtained from racetic forms in a manner known per se by conventional separation methods.

The compounds of formula (I) and (i) may be prepared in a manner known per se (cf. DM Evans et al., Chem. Soc., Chem. Commuru 1982, 188. KN Zelenin et al., Khim, Geterotskikl, Soedin, 1982). 7.904) ·

According to the invention, compounds of formula I are prepared by reacting a compound of formula II

(II) in which

is as defined above, with a compound of formula III

(III) in which:

The foregoing meanings are to be understood.

The compounds of formula (I) or (Ia) are then optionally converted into their salts or separated. The other optical isomers are preferably carried out in a solvent, suitable solvents are, for example, aromatic hydrocarbons, such as benzene, toluene and xylene; acetone, cyclohexanone and ethyl ethyl ketone; ethers, such as tetrahydrofuran, dioxane and diethyl ether, halogenated hydrogen atoms such as chloroform, tetrachloroethane and chlorobenzene alcohols, such as ethanesters, such as ethyl acetate, aliphatic aids, such as dinethylforma; id and dinethylacetaididioethylsulfoxide and other solvents which have an adverse effect on the reaction.

The reaction temperature may vary within a wide range from -10 to 200 ° C. Preferably, temperatures ranging from room temperature to about 150 ° C are used.

Pyridinecarbonyl derivatives of the general formula II which are used as starting materials and also the hydrazides of the thiobenzoic acids of the general formula III which are also used as the starting materials are known and can be prepared analogously or according to known processes OPf;

The compounds of the formula I or Ia can further be produced by a process of the type consisting in the reaction of a compound of the formula IV

(IV) wherein

R1 _and R2 have the same meanings as metal sulfide

The compounds of the formula I or Ia can then be converted into their compounds in known manner or separated into optically active isoners.

This process is preferably carried out in a polar solvent, such as water, an alcohol such as methanol or ethanol. The cyclization reaction is carried out with a metal sulfide, preferably a soluble metal sulfide, such as sodium sulfide or potassium sulfide, or with a corresponding hydrogen sulfide. advantageous alkaline reaction medium ·

The reaction temperature may be between -15 ° C and 100 ° C. Preferably, a temperature range of -10 to +50 ° C is used, for example room temperature ·

Substituted 2 ', 3-diazabutadienes of formula (iv) which, as novel compounds, serve as starting materials for the latter process can be prepared analogously to known methods (cf. W, T, Flowers et al., Chem., Soc., Perkin. Trans, 1 (2), 349, 1981), As explained below;

02

whereas

R 1, Ran have the above meanings.

The compounds of the formulas I and Ia, respectively, have been found to have excellent insecticidal and acaricidal activity with good plant tolerance and low warm-blood toxicity. These substances are particularly suitable for controlling insects and mites, i.e. pests which attack plants and animals.

The compounds of the formulas I and Ia, in particular, are suitable for controlling insects of the order of the butterflies (Lepidoptera), beetles (Coleoptera), even-winged insects (Homoptera), bugs (Heteroptera), two-wings (Dioptera), thrips (Thysanoptera), , lice (Anoplura), Siphonaptera, lice (Mallophaga), Scaly (Thysanura), termites (Isoptera), book flies (Psocoptera) and hymenoptera (Hymenoptera), as well as representatives of the order mites (Acarlna).

The good insecticidal and acaricidal activity of the compounds according to the invention corresponds to a mortality of at least 50 to 60% of said pests.

The compounds of the formulas I and Ia according to the invention can in particular be used to control various insects which are harmful to plants, in particular insects which are harmful to ornamental plants, in particular in cotton, vegetable, rice and fruit crops. In this context, it should be pointed out that the compounds are characterized by a very pronounced systemic, but in particular contact, action on sucking insects, in particular on insects of the Aphadidae family, such as Aphis fabae, Aphis craccivora and Peach aphids (e.g. Myzus persicae), which are difficult to control by conventional means.

The compounds of the formulas I and Ia, furthermore, are characterized by a good action against the larval stages of insects and nymphs, in particular biting pests. The compounds of the formula I can then be used with great results against harmful cicadas, especially in rice crops. The compounds according to the invention are furthermore suitable for combating ectoparatites, for example buzzers (Lucilia sericata), as well as ticks on domestic and utility animals, for example by treating animals, stables and pastures.

The effect of the compounds according to the invention or of the compositions containing them can be substantially expanded and adapted to the given conditions by the addition of further insecticides and / or acaricides.

Přís suitable additives are, for example, representatives of the following groups of active substances: organic phosphorous compounds, nitrophenols and their derivatives, formamidines, ureas, carbamates, pyrethrolides, chlorinated hydrocarbons and preparations based on Bacillus thuringlensis.

The compounds of the formulas I and I, respectively, are used in the unaltered state or preferably together with auxiliaries used in the preparation of such compositions and are thus processed, for example, into emulsion concentrates, sprayable solutions or further dilute solutions, emulsion concentrates, wettable powders, soluble powders, dusts, granules, as well as encapsulated granules, for example in polymeric substances · Methods of application, such as spraying, fogging, dusting, scattering or potting, are selected in accordance with the intended objectives and conditions.

The compositions, i.e. compositions containing the active ingredient, optionally combining these active ingredients with other insecticides or acaricides, and optionally a solid or liquid additive, preparation or concentrate, are prepared in a known manner, for example by thoroughly mixing and / or grinding the active ingredients with carriers. Examples are solvents, solid carriers and surfactants (surfactants).

Aromatic hydrocarbons, preferably C8-C12 fractions, such as mixtures of xylenes or substituted naphthalenes, phthalic acid esters, such as dibutyl phthalate, aliphatic hydrocarbons, such as cyclohexane, paraffin hydrocarbons, alcohols and glycols, as well as their ethers, can be used as solvents and esters, such as ethanol, ethylene glycol, ethylene glycol monomethyl ether or ethylene glycol monoethyl ether, ketones. Such as cyclohexanone, strongly polar solvents such as N-methyl-2-pyrrolidone, dlmethylsulphoxide or dimethylformamide, and optionally epoxidized vegetable oils, such as coconut oil or soybean oil or water as solid carriers, for example for dusts and dispersible powders generally natural stone meal, such as limestone, talc, kaolin, montmorillonite or attapulgite · Highly disperse silicas or highly disperse absorbent polymers may also be added to improve the physical properties □ porous-type substances, such as, for example, granular, adsorptive granular carriers, pumice stone, brick gossip, sepiolite or bentonite and, for example, limestone or sand are suitable as non-sorptive carrier materials. In addition, a variety of granular materials of inorganic or organic origin may also be used, such as especially dolomite or comminuted residues. n · ⁴ □ as surface-active compounds are, depending on the nature of the active ingredient of formula I or Ia, or combinations of these active ingredients with other insecticides or acaricides, which are used in the formulation, non-ionic, cationic and / or anionic surfactants having good emulsifying, dispersing and wetting properties. Surfactants are also mixtures of surfactants.

Suitable anionic surfactants can be both water-soluble soaps and water-soluble synthetic surface-active compounds.

□ alkali metal, alkaline earth metal or optionally substituted substituted ammonium salts such as sodium or potassium salts of oleic acid or stearic acid or salts derived from soaps of the higher fatty acids (C 10 -C 22) are suitable as soaps. Natural fatty acids, which can be obtained, for example, from coconut oil or phthalic oil. As the surfactants, the salts of the fatty acid with methyltaurine as well as the modified and unmodified phospholipids must also be mentioned.

however, synthetic surfactants, in particular fatty sulfonates, fatty sulfates, sulfonated benzimidazole derivatives or alkylarylsulfonates, are more commonly used.

The fatty sulfonates or fatty sulfates are generally present in the form of alkali metal, alkaline earth metal or optionally substituted ammonium salts and generally contain an alkyl group of 8 to 22 carbon atoms, the alkyl moiety also comprising an alkyl moiety of acyl groups, such as examples include the sodium or calcium salt of ligninsulfonic acid, dodecylsulfuric acid ester, or a mixture of sulfated fatty alcohols prepared from natural fatty acids. Also included are salts of sulfuric acid esters and sulfonic acids with fatty alcohol and ethylene oxide adducts. The sulfonated benzimidazole derivatives preferably contain two sulfo groups and a C 8 -C 22 fatty acid residue. Alkyl larylsulfonates are, for example, sodium, calcium or triethanolamine dodecylbenzenesulfonic acid, dibutylnaphthalenesulfonic acid or the naphthalenesulfonic acid-formaldehyde condensation product. Also suitable are corresponding phosphates, such as salts of the phosphoric acid ester of the p-nonylphenol adduct with 4 to 14 moles of ethylene oxide.

□ suitable nonionic surfactants are, in particular, derivatives of polyglycol ether of aliphatic or cycloaliphatic alcohols, saturated or unsaturated fatty acids and alkylphenols, which may contain 3 to 30 glycol ether groups having 8 to 20 carbon atoms in the (a11phatic) hydrocarbon radical and 6 to 18 carbon atoms in alkyl radical of alkylphenols. Other suitable nonionic surfactants are the adducts of polyethylene oxide and polypropylene glycol, ethylenediaminopolypropylene glycol and an alkylpolypropylene glycol having from 1 to 10 carbon atoms in the alkyl chain containing 20 to 250 ethylene glycol ether groups and 10 to 100 propylene glycol ether groups. Said compounds usually contain 1 to 5 units of ethylene glycol per propylene glycol unit.

Příklady examples of non-ionic surfactants include nonylphenol polyethoxyethanols, polyglycol ethers, castor oil, polypropylene adducts with polyethylene oxide, tributions of phenoxypolyethoxyethanol, polyethylene glycol and octylphenoxypolyethoxyethanol. Also suitable are fatty acid esters of polyoxyethylene sorbitan, such as polyoxyethylene sorbitan trioleate.

The cationic surfactants are in particular quaternary ammonium salts which contain as a substituent on the nitrogen atom at least one alkyl group having 8 to 22 carbon atoms and, as further substituents, lower or halogenated alkyl groups of the benzyl group or lower hydroxyalkyl groups. These salts are preferably in the form of halides, methylsulfates or ethylsulfates, and examples include stearyltrimethylammonium chloride and benzyl di- (2-chloroethyl) ethylammonium bromide.

Surfactants useful in the formulation of compositions are described, for example, in the following publications:

* Mc Cutcheon's Detergents and Emulsifiers Annual * Mc Publishing Corp., Ridgewood, New Jersey, 1979 Helmut Stache 'Tensid Taschenbuch', by Hanser Verlag Munich / Vienna 1981.

the pesticidal preparations contain, as a rule, from 0.1 to 99%, in particular from 0.1 to 95%, of an active compound of the formula I or of a combination of the active compound of the formula I with other insecticides or acaricides, 1 to 99.9% of a solid or liquid additive; 0 to 25% _t, in particular 0.1 to 20% tensides. While concentrated formulations are preferred as marketed formulations, the end consumer generally uses dilute formulations having a substantially lower concentration of active ingredient.

the compositions may also contain other additives, such as stabilizers, antifoams, viscosity regulators, binders, adhesives, as well as fertilizers or other active ingredients, to achieve special effects.

Examples illustrating a process for the preparation of active substances

Example 1

Preparation of 2- (4-chlorophenyl) -5- (pyrid-3-yl) -4,5-dihydro-1,3,4-thiadlazole

39.2 g of p-chlorothiobenzoic acid hydrazide are dissolved in 350 l of ethanol. 21.4 g of pyrldyl-3-aldehyde (dissolved in 20 ml of ethanol) are added dropwise to this solution under a nitrogen atmosphere. · The reaction temperature is maintained by cooling to 20 DEG C. After completion of the addition, the reaction mixture is further stirred at reflux for 1 hour. The filtrate is concentrated to 3/4 of its original volume and the precipitated product is filtered off, washed with hexane and dried.

m.p. 106-108 ° C (Compound No. 1.1)

Example 2

Preparation of 2- (3-nitrophenyl) -5- (pyridin-3-yl) -4,5-dihydro-1,3,5-thiadiazole

A solution of 8.7 potassium hydroxide in 100 ml of ethanol is saturated with hydrogen sulfide. To this solution is added dropwise 8.7 potassium hydroxide in 100 ml of ethanol, then 22.4 g of 1-chloro-1- (3-Nitrophenyl) -4- (3-pyridyl) -2,3-diazabutadiene. The reaction mixture is further stirred for 1 hour at room temperature, then concentrated and the residue is taken up in ethyl acetate. The ethyl acetate solution was washed twice with water and twice with saturated sodium chloride solution, dried over sodium sulfate, filtered, and evaporated.

mp 109-111 ° C (Compound No. 1.2)

The following compounds of formula (Ia) were prepared in an appropriate manner as described in the above examples

Compound _of the position of the pyridyl group * 1 ^R 2 ^R 3 physical data 1 * 3 2 ti 4-C1 H m.p. Mp 91-93 ° C 1.4 4 H 4-C1 H m.p. 145 - 147 ' 1.5 3 -CH ₃ 4-C1 H m.p. 119 - 120 ' 1.6 3 H H H m.p. Mp 70-73 ° C 1.7 3 -CH ₃ H H 20 May »1,6450 1.8 4 .CH ₃ 4-C1 H m.p. 123 - 125 ' 1.9 2 • CH ₃ 4-C1 H m.p. Mp 92-93 ° C 1.10 3 H 2-CL H m.p. 125 - 126 ' 1.11 .3 H 2-F H m.p. 78-80 ° C 1.12 3 H _4-CH3 H t, .t. 118 - 119 ' 1.13 3 H 4-CF3 H m.p. 98-100 ° l 1.14 3 H 3-F H m.p. Mp 73-75 ° C 1.15 3 H 4-F H m.p. 103 - 105 ' 1.16 3 H 4-ВГ H m.p. 126 - 128 ' 1.17 3 M 3-C1 H m.p. Mp 86-87 ° C 1.18 3 W 3-CH3 H m.p. 80-82 ° C 1.19 3 H 4-0CH ₃ H m.p. Mp 93-94 ° C 1.20 3 H 3-C1 4-C1 m.p. 104 - 108 '

The following compounds of formula (Ia) can also be obtained as described above

the position of the pyridyl group «1 ^R 2 ^R 3 2 - ^C 4 ^H 9 H _H-CH3 4 H H 4-nC ₄ H ₉ 2 -CH ₃ 4-0CH ₃ H 4 - ° 2 ^Η 4 H -OCH ₃

CS 269982 82

the position of the pyridyl group ^R 1 ^R 2 ^R 3 2 -Nc ₃ H ₇ 2-F H 4 H 2-C1 6-C1 3 H 2-C1 4-C1 3 H 2-C1 3-C1 3 H 3-F 5-F 3 H 3-F 4-F 3 H 2-F 4-F 3 H 2-F 3-F 3 H ⁴ ' ^C 2 ^H 5 H 3 ’ H 3-C1 5-C1

Further, the following salts of the compounds of formula (Ia) can be obtained as described above

compound no. the position of the pyridyl group ^R 1 r ₂ ^R 3 salt-forming acid physical data (° C) 2.1 3 H 4-C1 H Elavelic acid m.p. 200 - 201 2.2 3 H 4-C1 H Н0Г m.p. 232-234 2.3 3 H 4-C1 H p-tolthienesulfonic acid m.p. 261-262 2.4 3 H 4-C1 H benzoic acid m.p. 70-72 2.5 3 H 4-C1 H HCl m.p. 192 193 2.6 3 H 4-C1 H HBr m.p. 228-229

Examples of compositions and preparations for the active compounds of the formulas I and Ia according to Examples 1 and 2, or for combinations of these active compounds with other insecticides or acaricides (% by weight)

Example з

1 · Wettable powder E) (b) C) active ingredient or combination of active ingredients 25% 50% 75% sodium dinofinsulfonic acid 5% 5% sodium lauryl sulfate 3% - 5%. natriuradi isobutylnaphthalenesulfonate 6% 10% octylphenolpolyethylene glycol ether (7 to 8 moles of ethylene oxide) 2% highly disperse silicic acid 5% 10% 10% kaolin 62 27% - Active substance or combination of active substances is mixed with the ingredients and the mixture is dissolved mills in a suitable mill · Wettable powder is obtained, which can be diluted with water to suspensions each desired concentration·

2. Emulsion concentrate Active substance or active ingredient combination octylphenolpolyethylene glycol ether (4 to 5 moles of ethylene oxide) calcium dodecylbenzenesulphonic acid Castor oil polyglycol ether (36 moles of ethylene oxide) cyclohexanone Mixture of xylenes

From this concentrate can be diluted by concentration ·

3. Dust the active ingredient or active ingredient combination talc kaolin

Directly usable dust is obtained and the mixture obtained is ground in a suitable mill.

%% ‘%

% water to prepare emulsions each required

(a) (b)% 8% -% - 92%, in which the active substance is mixed with a carrier

CS 2699-2 B2

4 · Granulate prepared by extrusion active substance or combination of active substances 10% lignin sulphonic acid sodium salt 2% carboxymethylcellulose 1% kaolin 87%

The active ingredient is mixed with the ingredients, the mixture is ground and moistened with water. This mixture is processed on an extruder, then granulated and the granulate obtained is dried in an air stream.

5 · Granulate obtained by coating the active substance or active substance combination 3% polyethylene glycol (molecular weight 200) 3% kaolin 94% The finely divided active substance or active substance combination is uniformly applied to a kaolin moistened with polyethylene glycol in a mixing device. In this way a dust-free coated granulate is obtained.

6 · Suspension concentrate active substance or active substance combination. 40% ethylene glycol 10% nonyl phenolpolyethylene glycol ether (15 mol ethylene oxide) 6% sodium lignin sulphonic acid 10% carboxymethylcellulose 1%

37% aqueous formaldehyde solution 0.2% silicone oil in the form of 75% aqueous emulsion 0.8% water 32% The finely divided active ingredient or active ingredient combination is intimately mixed with the ingredients. In this way, a suspension concentrate is obtained from which suspensions of any desired concentration can be prepared by dilution with water *

Example 4

Effect against house fly (Musea domestica)

Weigh 50 g of freshly prepared larvae nutrient substrate into beakers. From a 1% (w / w) acetonic solution of the active substance in question, a certain amount is measured by pipette and dropped onto the nutrient substrate contained in the beakers to achieve an active substance concentration of 400 ppm * After mixing the substrate, acetone is allowed to evaporate for at least 20 hours · 25 day-old larvae of the house fly (Musea domestica) are then placed in a beaker containing the nutrient substrate treated for each active substance. When the larvae have pupae, the resulting pupae are separated by washing with water from the substrate and kept in containers closed with a net lid.

In each case, the washed pupae are counted (toxic effect of the active substance on larvae development), after 10 days the number of specimens of the house-hatched from the pupae is determined.

Compounds 1.1, 1.2, 1.3, etc. to 1.20 show at least 50 to 60% mortality in housefly in this test.

Example 5

Effect against buzzard larvae (Lucillia sericata)

To 9 ml of culture medium, at 50 ° C, add 1 ml of an aqueous preparation containing 0/5% of the active substance. About 30 freshly stripped specimens of the buzzard (Lucillia sericata) are then added to the broth. After 48 and 96 hours, the insecticidal effect was determined by determining mortality.

Compounds 1.1 to 1.20 of Examples 1 and 2 exhibit at least 50-60% mortality in the buzzard larvae in this test.

Example 6

Effect against mosquito larvae (Aedes aegypti)

Pipette 0.1 ml of an acetonic solution of the active ingredient into a surface of 150 ml of water contained in the vessel to obtain a concentration of 200 ppm. After evaporating the acetone, 30-40 two-day mosquito larvae are placed in the vessel. Mortality was found after 2 and 7 days.

Compounds 1.1 to 1.20 of Examples 1 and 2 exhibit at least 50-60% mosquito larvae mortality in this assay.

Example 7

Contact effect on Aphis craccivora

Bean seedlings (vicia faba) aged 4 to 5 days grown in pots are always occupied about 200 specimens of aphid Aphis craccivora before the beginning of the experiment. The plants so treated are sprayed directly 24 hours later up to the wetting stage with an aqueous preparation containing the test compound. Two plants were used for each test compound. The mortality results are evaluated after a further 24 and 72 hours, the experiment is carried out at a temperature of 21 to 22 ° C and a relative air humidity of about 55%. up to 100% mortality. Compounds Nos. 1.6, 1.11, 2.1, 2.2, 2.3, 2.4 and 2.5 exhibit the same effect at 400 ppm.

Example 8

Systemic effect on Aphis craccivora

The rooted bean plants are transplanted into pots containing 600 ml of soil. Then the soil is poured with 50 ml of test compound preparation (which was obtained from 25% wettable powder) at a concentration of 800 ppm directly in pots.

After 24 hours, the above-ground parts of the plants are occupied by Aphis craccivora aphids and the plants are coated with a plastic cylinder so that the aphids are protected from possible direct contact with the test substance or from contact with the test substance in the form of a gas.

The mortality is evaluated 48 and 72 hours after the start of the experiment. Two plants are used for each test substance, one in a separate pot. The experiment is carried out at 25 ° C and at about 70% humidity.

Compounds 1 · 1 to 1 · 2Ο of Examples 1 and 2 exhibit at least 50 to 60% mortality in shallow Aphis craccivora in this test.

Example 9

Contact effect no shallow peach (Myzиз persicae)

About 4 to 5 days old bean seedlings (Vicia faba) grown in water are always occupied by about 200 specimens of shallow peach (Myzus persicae) before the experiment. · The treated plants are sprayed 24 hours later up to the wetting stage with an aqueous suspension containing up to 200 ppm test compound · 2 plants are used per test substance · Evaluation of mortality values is performed 24 and 72 hours after application · Experiment is carried out at 21 to 22 ° C and at about 60% relative humidity ·

In this test, 80-100% mortality is achieved using Compound # 1 of Example 1 at 200 ppm, Compound # 2 · 5 at 3 ppm, and Compounds # 2.1, 2 · 2, 2.3, and 2.4 at concentration 50 ppm ·

Example 10 systeoic effect on shallow peach (Myzus persicae)

Rooted cabbage plants are transplanted at 4-5 leaf stages into pots containing 60 ml of soil. Then the soil is directly covered with an aqueous preparation of the test compound (obtained from 25% wettable powder) at a concentration of 800 ppm each.

After 24 hours, the above-ground parts of the plants so treated are populated with Myzus persicae, and the plants are covered with plastic cylinders to protect them from being in direct contact with the test substance or against contact with the test substance in the form of gas.

The% mortality was evaluated 48 hours after the start of the experiment. Two plants grown in separate pots were used for each test compound. the experiment was carried out at a temperature of about 25 ° C and 60% relative humidity.

Compounds 1 · 1 to 1 · 20 of Examples 1 and 2 exhibit at least 50 to 60% mortality in Myzus persicae in this test.

Example 11

Penetrating effect on shallow Aphis craccivora (leaf penetration)

In a plastic beaker 8 cm high (about 6 cm diameter), place a suitable small piece of the plant god Vicia faba, which is heavily infested with aphids of the species Aphis craccivora · Cover the beaker with a plastic lid with a hole cut out in the middle 2 cm diameter · A leaf of the bean plant (Vicia faba) is placed on the opening in the lid without being separated from the planted plant. The sheet is then fixed with a second lid with a beaker opening above the opening of the first lid. From the bottom side, ie from the side of the opening of the first cap, the shallow leaf in the beaker now infects the leaf of the plant that is feeding them. · On the upper side, an aqueous preparation of the test substance at 400 ppm is applied evenly over the area. pipette, test to be tested, 2d if the test compound applied to the top of the leaf serving as aphid food diffuses in sufficient quantity through the leaf to the bottom of the leaf to kill the sucking aphids ·

J

The experiment is carried out at about 20 ° C and at 60% relative humidity. Mortality percentages are evaluated 48 hours after drug administration.

Compounds 1.1 to 1.20 of Examples 1 and 2 exhibit at least 50-60% mortality in Aphis cracclvora in this test.

Example 12

Eating effect on Laodelphax striatellus and Nilaparvata lugens (nymphs)

This test is performed on growing plants. For this purpose, 4 rice plants (8 mm thick) are grown in pots (8 cm in diameter) in each case.

on

The rotating plate plants are sprayed with 100 ml of an acetonic solution containing 800 ppm of the respective active ingredient. After the spray layer has dried, each plant is occupied with 20 nymphs of the third stage insects. In order to prevent the cicadas from escaping, the occupied plants are always tilted with glass cylinders open on both sides and covered with gauze. The nymphs are maintained up to the next stage of development for 10 days on the treated plants. Mortality percentages are evaluated on days 1, 4, and 8 after treatment.

Compounds 1.1 to 1.20 of Examples 1 and 2 exhibit at least 60% mortality in the test pests in this test.

Example 13

Ovicidal effect on Laodelphax striatellus and Nilaparvata lugens

The test is performed on growing plants. For this purpose, 4 rice plants (8 mm thick, 20 cm high) are grown in a pot (8 cm diameter).

The plants are sprayed on a rotating plate with 100 ml of an acetonic solution containing 400 ppm of the active ingredient. After the spray layer has dried, each plant is occupied by 3 adult female insects tested. To prevent animals from escaping, each occupied plant is covered with a glass cylinder and covered with gauze at the top. The females are kept for 4 days until egg laying on the treated plant and then removed.

About 8 days after occupation, young cicadas hatch and count, and the percent mortality is determined by comparing the number of hatched larvae on treated plants and untreated control plants.

Compounds No. 1.1 to 1.20 of Examples 1 and 2 exhibit at least 50-60% ovicidal activity on the eggs of the test pests in this test.

object of the invention

Insecticidal and acaricidal composition, characterized in that it contains at least one optionally substituted 2-phenyl-5-pyridyl-4,5-dihydro-1,3,4-thiadiazole of the general formula I (I) in which:

Claims (19)

x (C 1 -C 4) or trifluoromethyl, and n is 0 to 2, or a salt or optical isomer of a compound of formula (I); 2. A composition according to claim 1, characterized in that it contains at least one compound of the formula I in which n is 1 or 2 and R @ 1 and R @ 2 are as defined in point 1. Composition according to item 182, characterized in that it contains at least one compound of the formula Ia (Ia) as an active ingredient in which: R ^ represents a hydrogen atom or an alkyl group having from 1 to 4 carbon atoms, R? and R 8 are independently hydrogen, halogen, C 1 -C 4 alkyl, trifluoromethyl or C 8 -C 4 alkoxy, or such compounds; 4. A composition according to claim 3, characterized in that it contains at least one compound of the formula Ia in which r @ 1 represents a hydrogen atom, a methyl group or an ethyl group, R @ ₂ and R @ 3 independently represent a hydrogen atom or an atom. halogen in position 2 and / or 4 · 5. A composition according to claim 3 or 4, characterized in that it contains at least one compound of the formula Ia in which R @ 1 represents a hydrogen atom and a and r @ ₂ are as defined in point 3 or 4 as active ingredient. Composition according to one of Claims 1 to 5, characterized in that it contains, as active ingredient, at least one compound of the formula I or ia in which R 1 represents a hydrogen atom and the other substituents have the meaning given in any one of items 1 to 5 . Composition according to one of Claims 1 to 6, characterized in that it contains, as an active ingredient, at least one compound of the general formula I and / or ia in which the pyridyl group is bound by its 3-position to the 5-position of 4,5-dihydro-1; 3,4-thiadiazole ring, the other substituents being as defined in any one of items 1 to 6. 8. A composition according to claim 5, characterized in that It contains, as an active ingredient, a compound of the formula 9. A composition according to claim 5, characterized in that it contains a compound as an active ingredient 10. A composition according to claim 5, wherein the compound of the formula contains as active ingredient CS 269982 82 A process for the preparation of optionally substituted 2-phenyl-5-pyridyl-4,5-dihydro-1,3,4-thiadiazoles of the general formula I in which: R @ 1 represents a hydrogen atom or a C1 -C4 alkyl group, R is C 1 -C 4 alkyl, halogen, C 1 -C 4 alkoxy or trifluoromethyl, and is 0 to 2, as well as their salts and optical isomers, as defined in item 1, characterized in that: It is a compound of formula (II) wherein: R _x, as defined above, is a compound of formula III (III) wherein: The wounds have the meanings given above, whereupon the optionally obtained compound of formula I is converted into its salt or separated into its salt. optical isomers. 12. The process of claim 11, wherein n is 1 or 2 a 13. A process according to claim 12, wherein the compounds of formula (II) are used as starting materials with the formula (III) to give compounds of formula (I), the other symbols being as defined in point 11. by reacting III to form compounds of formula (Ia) H (Ia) wherein H is C 1-4 alkyl, and R 6 is independently H, halogen, C 1-4 alkyl, trifluoromethyl or C 1-4 alkoxy carbon, and the compounds obtained are optionally converted into their salts. Process according to Claim 13, characterized in that the corresponding compounds of the formulas II and III are used as starting materials to give compounds of the formula Ia in which R R represents a hydrogen atom, a methyl group or an ethyl group, R ^ and R _3. are independently hydrogen or halogen in position 2 and / or position 4. 15. A process according to claim 13 or 14, wherein the corresponding compounds of formula II and III are used as starting materials to give compounds of formula Ia in which R @ 1 is hydrogen and the other substituents are as defined in point 13, or 14. Process according to one of Claims 11 to 15, characterized in that the corresponding compounds of the formulas II and III are used as starting materials to give compounds of the formulas I and Ia, respectively, in which the radical is hydrogen and the other substituents are as defined in any of points 11 to 15. Process according to one of Claims 11 to 16, characterized in that the corresponding compounds of the formulas II and III are used as starting materials to give compounds of the formulas I and Ia, respectively, in which the pyridyl group is bound by its 3-position to the 5-position. The 4,5-dihydro-1,3,4-thiadiazole ring and the general symbols have the meanings given in any one of items 11 to 16. CS 269982 82 18. A process according to claim 15, wherein the starting compound is a starting material and the starting material is a starting material to form a compound of the formula: A process according to claim 15, wherein the corresponding compounds of the formulas II and III are used as starting materials to form a compound of the formula У