CA2013785A1 - Pest control agents - Google Patents

Abstract

PS/5-17541/=

Pest control agents Abstract of the Disclosure There are disclosed novel substituted N-amino-1,2,4-triazinones of formula I

(I) wherein R1 is C1-C12alkyl or C3-C7cycloalkyl, R2 and R3 are each independently of the other hydrogen or C1-C6alkyl, R4, R5, R6 and R7 are each independently of one another hydrogen, halogen, Cl-C3alkyl,

Description

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PS/5-17541/=

Pest control a~ents The present invention relates to novel insecticidal N-amino-1,2,4-triazinones, to their preparation and to intennediates for their preparation5 to compositions which contain said aminotriazines, and to the use thereof in pest control.

The aminotriazines of this invention have the formula I

R3 0 ~~ R7 (I) H R4 1~ n wherein Rl is Cl- Cl2alkyl or C3-C7cycloalkyl, R2 and R3 are each independently of the other hydrogen or Cl-C6alkyl, R4, R5, R6 and R7 are each independently of one another hydrogen, halogen, C~ 3alkyl, N~ , Cl-C3alkoxy or Cl-C3alkylthio, and n is O or 1, and to the salts thereof, with the proviso that n is 1, if simultaneously ~e pyridine ring is attached via the 3-position to the methylidene group and R4, Rs, R6 and R7 are each hydrogen.

The compounds of formula I can also be obtained in the form of acid addition salts.
Suitable acids for forming such salts are organie and inorganic aeids, ~or example hydro-ehlorie aeid, hydrobromie aeid, nitric acid, different phosphoric acids, sulfuric acid, acetic acid, propionic acid, butyric acid, valeric acid, oxalic acid, malonic acid, maleic acid, fumaric acid, lactic acid, tartaric acid or sa~licyclic acid.

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The alKyl groups by themselves or as moieties of other substituents may be straight-chain or branched. Typical of such alkyl groups are methyl, ethyl, propyl, isopropyl, butyl, isobutyl, sec-butyl, tert-butyl or pen~l, hexyl, octyl, decyl, dodecyl and the like, and the isomers thereof.

Suitable aL~coxy and aLkylthio groups may be straight-chain or branched and are e.g, typically, methoxy, methylthio, ethoxy, ethylthio and propoxy.

Cycloalkyl groups may be e.g., cyclop~opyl, cyclobutyl, cyclopentyl or cyclohexyl.

Halogens are suitably fluoro and chloro and also bromo and iodo. Preferred halogens are fluoro and chloro.

Preferred compounds of formula I are those wherein R1 is C1-C4alkyl; those wherein R1 is methyl, ethyl, isopropyl or cyclopropyl; and those wherein n is 1.

Also preferred are the compounds of formula la R,~R6 R1~< ~N ~ CHJ~ Jl~ (Ia) N ~ ~C~ n H
wherein Rl to 3~7 have the above given meanings.

In formulae I and Ia above, the substituents R2 and R3 are conveniently each independently of the o~her hydrogen or methyl, preferably hydrogen.

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Among the compounds of formula I, those of formula Ib R1~<N ~ N = CHI~R~; (Ib) n wherein Rl, R4 to R7 and n are as defined above, may also be highlighted.

On account of the* biological activity, those compounds of formula Ib are preferred in which Rl is methyl or ethyl, R5 is hydrogen, R4, R6 and R7 are each independently of one another chloro, methyl, methoxy or amino.

Particularly preferred compounds of this invention are those of formulae I, Ia and Ib wherein R6 is hydrogen; or wherein R4, R5, R6 and R7 are hydrogen and n is 1; or wherein Rl is methyl.

Further preferred compounds of formula Ib are those in which R4, Rs and R6 are each independently of one another methyl or fluoro and R7 is hydrogen, methylthio or dimethylamino, and n is 0.

Among ~he compounds of formula I, those compounds of forrnula Ic Rl~,N CH~N

N~N~C~O (Ic) H
wherein Rl, R2 and R3 are as defined above, also merit special mention.

On account of its biological aclivity, 2,3,4,5-tetrahydro-3-oxo-4-[(pyridin-N-oxide-3-yl)-methyleneimino]-6-methyl-1,2,4-triazine of formula 2~37~

N ~ , C
O

is to be singled out for special men~ion.

The compounds of formula I can be prepared by processes which are known per se, for example by reacting an aminotriazinone of formula II

R~< ~NH2 N ~ ~ (II) N O
H

wherein Rl is Cl- Cl2alkyl or C3-C7cycloaLkyl, R~ and R3 are each independently of the other hydrogen or Cl-C6aLtcyl, with an aldehyde of for nula III

,X~, N ~ (III) R4 ~
n wherein R4, R5, R6 and R7 are each independently of one another hydrogen, halogen, Cl-C3alkyl, /~2 N\ , Cl-C3aLIcoxy or Cl-C3aLIcylthio, and n is O or 1, ~R3 with the proviso that n is 1, if simultaneously the pyridine ring is attached via the 3-position to the methylidene g,roup and R4, Rs, R6 and R7 are each hydrogen, 2~ 37~

and isolating the reaction product. If desired, the resultant compounds can be converted into their salts in conventional manner.

The process is ordinarily carried out under normal pressure in the presence of a catalytic amount of a strong acid and in a solvent. The reaction temperature is in the range from +10 to 100C, preferably from +40 to 80C. Suitable acids are strong inorganic acids such as mineral acids, preferably hydrochloric acid. Suitable solvents are alcohols, ethers and ethereal compounds, nitriles or also water.

The starting aminotriazinones of forrnula II are known or can be prepared in a manner which is known per se, for example by cyclic rearrangement with hydrazine hydrate, i.e.
reacting an oxadiazolone of formula IV
R

2 ~ 3 ,C - CO--R~ (IV) N--N
CF3J~o/~O

with hydrazine hydrate (H2N-N~I2-H20), wherein Rl7 R2 and R3 are as defined above. The process for the preparation of the aminotriazinones of formula II is ordinarily carried out under normal pressure and with or without a solvent. The reaction temperature is in the range from +15 to 120C, preferably from +20 to 80C. Suitable solvents are typically water, nitriles such as acetonitrile, alcohols, dioxane or tetrahydrofuran.

The above mentioned oxadiazolones of formula IY can be prepared by processes which are known per se, for example by reacting 5-trifluoromethyl-1,3,4-oxadiazol-2~3H)-one of formula V

N--N (V) CF3--~o/C~O

with a ketone of formula VI

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l2 X--C--CO-R1 (YI) in which formulae the substituents Rl, R2 and R3 are as defined above and X is halogen.
The process for the preparation of the oxadiazolones of formula IV is carried out under normal pressure and in the presence of a base and in a solvent. The reaction temperature is in the range from 0 to +150C, preferably from +20 to 100C. Suitable bases are organic and inorganic bases such as trimethylamine, alcoholates, sodium hydroxide or sodium hydride. Suitable solvents are typically alcohols, halogenated hydrocarbons such as chloroform, nitriles such as acetonitrile, tetrahydrofuran, dioxane, dimethyl sulfoxide or also water.

Among the aminotriazinones of formula II, 4-amino-6-phenyl-1,2,4-triazin-3-one is known (Liebigs ~nnalen der Chemie, 749, 125 (1971), i.e. the compound of formula II in which Rl is phenyl, and R2 and R3 are each hydrogen. The compounds of formulae V and VI are known or can be prepared by processes which are known per se. The aldehydes of formula III, wherein n is 0, are known or can be prepared by processes which are known per se ~Z. Chemie 184 (1970), J. Org. Chem. 46, 4836 (1981), Eur. J. Med. Chem. 12, 531 (1977), Heterocycles 26, 4836 (1981), J. Org. Chem~ 53, 5320 (1988)]. The compounds of formula III (n = 1) are usually prepared starting from the corresponding aldehyde (n = 0) by reaction with a suitable oxidising agent such as m-chloroperbenzoic acid, whereby the aldehyde group is temporarily protected with a suitable protective group. To this end the aldehyde group can, for example, be acetylised.

The process of this invention is suitable for the preparation of compounds of formula I
using pyridine derivatives (n = 0~ as well as pyridine-N-oxides (n = 1) as starting materials. Depending on the desired final compound, a suitable free pyridine aldehyde (n = 0) or the N-oxide thereof (n = 1) is used.

It has now been found that the instant compounds of formula I are better tolerated by warm-blooded animals and have greater stability than known phosphoric acid esters and carbamates, while being well tolerated by plants. They are therefore most suitable for use as pest control agents, especially for controlling pests of plants, in particular insects.

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The compounds of formula I are particularly suitable for controlling insects of the orders:
Lepidoptera, Coleoptera, Homoptera, Heteroptera, Diptera, Thysanoptera, Orthoptera, Anoplura, Siphonaptera, Mallophaga, Thysanura, Isoptera, Psocoptera and Hymenoptera, as well as representatives of the order Acarina.

Most particularly, plant-injurious insects, especially plant-injurious insects in ornamentals and crops of useful plants, in particular in cotton, vegetable, rice and fruit crops, can be controlled with the compounds of formula I. In this connection, particular attention is drawn to the fact that the compounds of formula I have a strongly pronounced systemic as well as contact action against sucking insects, especially against insects of the Aphididae family (e.g. against Aphis fabae, Aphis craccivora, Myzus persicae and Bemisia tabaci~
which can only be controlled with difficulty using known pesticides.

The good pesticidal activity of the compounds of formula I corresponds to a mortality of at least 5~-60 % of the above pests.

The activity of the compounds employed and of the compositions containing them can be substantially broadened and adapted to prevailing circumstances by addition of other insecticides and/or acaricides. Examples of suitable additives include: organophosphorus compounds, nitrophenols and derivatives thereof, formamidines, ureas, carbamates, pyrethroids, chlorinated hydrocarbons, and Bacillus thuringiensis preparations.

The compounds of formula I are used as pest control agents in unmodified form, or prefer-ably together with the adjuvants conventionally employed in the art of formulation, and are therefore formulated in known manner to emulsifiable concentrates, directly sprayable or dilutable solutions, dilute emulsions, wettable powders, soluble powders, dusts, granu-lates, and also encapsuladons in e.g. polymer substances. As with the compositions, the methods of application such as spraying, atornising, dusting, scattering or pouring, are chosen in accordance with the intended objectives and the prevailing circumstances.

The formuladons, i.e. the compositions, preparations or mixtures containing the compound (acdve ingredient) of formula I or combinations thereof with other insecticides or acari-cides, and, where appropriate, a solid or liquid adjuvant, are prepared in known manner, e.g. by homogeneously mixing and/or grinding the active ingredients with extenders, e.g.
solvents, solid carriers and, in some cases, surface-active compounds (surfactants).

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Suitable solvents are: aromatic hydrocarbons, preferably the fractions containing 8 to 12 carbon atoms, e.g. xylene rnixtures or substituted naphthalenes, phthalates such as dibutyl phthalate or dioctyl phthalate, aliphatic hydrocarbons such as cyclohexane or paraffins, alcohols and glycols and their ethers and esters, such as ethanol, ethylene glycol, ethylene glycol monomethyl or monoethyl ether, ketones such as cyclohexanone, strongly polar solvents such as N-methyl-2-pyrrolidone, dimethyl sulfoxide or dimethyl form-amide, as well as vegetable oils or epoxidised vegetable oils such as epoxidised coconut oil or soybean oil; or water.

The solid carriers used e.g. for dusts and dispersible powders are normally natural mineral fillers such as calcite, talcum, kaolin, montmorillonite or attapulgite. To improve the physical properties it is also possible to add highly dispersed silicic acid or highly dispersed absorbent polymers. Suitable granulated adsorptive calTiers are porous types, for example pumice, broken brick, sepiolite or bentonite; and suitable nonsorbent carriers are materials such as calcite or sand. In addition, a great number of pregranulated materials of inorganic or organic nature can be used, e.g. especially dolomite or pulverised plant residues.

Depending on the nature of the compound of formula I to be formulated, or of combina-tions thereof with other insecticides or acaricides, suitable surface-active compounds are non-ionic, cationic and/or anionic surfactants having good emulsifying, dispersing and wetting properties. The term "surfactants" will also be understood as comprising mixtures of surfactants.

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

Suitable soaps are the alkali metal salts, aLt~aline earth metal salts or unsubstituted or substituted ammonium salts of higher fatty acids (Clo-C22), e.g. the sodium or potassium salts of oleic or stearic acid, or of natural fatty acid mixtures which can be obtained, e.g.
from coconut oil or tallow o;l. Further suitable surfactants are also the fatty acid methyl-taurin salts as well as modified and unmodifled phospholipids.

More frequently, however, so-called synthetic surfactants are used, especially fatty sulfonates, fatty sulfates, sulfonated benzimidazole derivatives or alkylarylsulfonates.

The fatty sulfonates or sulfates are usually in the form of alkali metal salts, alkaline earth metal salts or unsubstituted or substituted ammonium salts and generally contain a C8-C22-alkyl radical which also includes the alkyl moiety of acyl radicals, e.g. the sodium or calcium salt of lignosulfonic acid, of dodecylsulfate, or of a mixture of fatty alcohol sulfates obtained from natural fatty acids. These compounds also comprise the salts of sulfated and sulfonated fatty alcohol/ethylene oxide adducts. The sulfonated ben~imida-zole derivatives preferably contain 2 sulfonic acid groups and one fatty acid radical containing about 8 to 22 carbon atoms. Examples of a1kylarylsulfonates are the sodium, calcium or triethanolamine salts of dodecylbenzenesulfonic acid, dibutylnaphthalene-sulfonic acid, or of a condensate of naphthalenesulfonic acid and formaldehyde. Also suitable are corresponding phosphates, e.g. salts of the phosphated adduct of p-nonyl-phenol with 4 to 14 moles of ethylene oxide.

Non-ionic surfactants are preferably polyglycol ether derivatives of aliphatic or cycloaliphatic alcohols, or saturated or unsaturated fatty acids and alkylphenols, said derivatives containing 3 to 30 glycol ether groups and 8 to 20 carbon atoms in the (aliphatic) hydrocarbon moiety and 6 to 18 carbon atoms in the alkyl moiety of the alkylphenols. Further suitable non-ionic surfactants are the water-soluble adducts of polyethylene oxide with polypropylene glycol, ethylenediaminopolypropylene glycol and alkylpolypropylene glycol containing 1 to 10 carbon atoms in the alkyl chain, which adducts contain 20 to 250 ethylene glycol ether groups and 10 to 100 propylene glycol ether groups. These compounds usually contain 1 to 5 ethylene glycol units per propylene glycol unit.

Representative examples of non-ionic surfactants are nonylphenolpolyethoxyethanols, castor oil thioxilate, polypropylene/polyethylene oxide adducts, tributylphenoxypoly-ethoxyethanol, polyethylene glycol and octylphenoxypolyethoxyethanol. Fatty acid esters of polyoxyethylene sorbitan, e.g. polyoxyethylene sorbitan trioleate, are also suitable non-ionic surfactants.

Cationic surfactants are preferably quaternary ammonium salts which contain, as N-substi-tuent, at least one C8-C~,aLkyl radical and, as further substituents, unsubstituted or halogenated lower alkyl, benzyl or hydroxy-lower aLkyl radicals. The salts are preferably in the form of halides, methylsulfates or ethylsulfates, e.g. stearyltrimethylammonium chloride or benzyl bis(2-chloroethyl)ethylarnmonium bromide.

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The surfactants customarily employed in the art of forrnulation are described e.g. in the following publications "McCutcheon's Detergents and Emulsifiers Annual", MC Publishing Corp., Ridgewood, New Jersey, 1979; Dr. Helmut Stache, "Tensid Taschenbuch" (Handbook of Surfactants), Carl Hanser Verlag, Munich/Vienna, 1981.

The pesticidal compositions usually contain 0.1 to 99 %, preferably 0.1 to 95 %, of a compound of formula I, 1 to 99.9 % of a solid or liquid adjuvant, and 0 to 25 %, preferably 0.1 to 25 %, of a surfactant, the percentages being by weight.

Whereas commercial products are preferably formulated as concentrates, the end user will normally employ diluted formulations of substantially lower concentration, for example 0.1 to 1000 ppm. In general, the concentration of compound of formula I - especially for crop areas - is 0.025 to 1.0 kg/ha, preferably 0.1 to 0.5 kg/ha, for example 0.1 to 0.25 kg/ha.

The compositions may also contain further ingredients, such as stabilisers, antifoams, viscosity regulators, binders, tackifiers as well as fertilisers or other chemical agents for obtaining special effects.

Examples:
1. Preparation of the compounds of formula I and their intermediates.

Example H 1: 2-Oxo-S-trifluoromethyl-2~3-dihydro- 1 ~3~4-oxadiazole-1-3-acetone 15 g (0.5 mol) of an 80% dispersion of NaH in oil are washed free of oil with petroleum ether and added to 125 ml of dimethyl formamide. Then 77 g (0.5 mol~ of S-trifluoro-methyl-1,3,4-oxadiazole-2(3H)-one in 250 ml of dimethyl formamide are added dropwise to this suspension at room temperature over 1 hour, and the mixture is stirred for 3 hours.
After addition of 55.5 g (0.6 mol) of chloroacetone, the reaction mixture is stirred for 16 hours at room temperature and then concentrated by evaporation. IJpon addition of 1000 ml of water to the residue, the solid precipitate is filtered with suction and dried, to give the title compound of formula 20~3r~

N N (compound 1.01) CF3--l~o~ 0 in the form of a colourless solid; m.p. 85C (yield: 96 g; 91.7%).

The following compounds of formula IV are prepared in analogous manner.

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Table 1:

N N ~ (IV) Compound Rl R2 R3 Physical data __ 1.01 CH3 H H m.p. 85C
1.02 i-C3H7 H H m.p. 74-75C
1.03 c(C~I3)3 H H m.p. 67C
1.04 C6Hs H H m.p. 100-102C
1.05 CH3 C~I3 H oil 1.06 CH3 CH3 CH3 oil 1.07 C2Hs H H m.p. 76-77C

1.08 /\ H H m.p. 77-78C
1.09 H H H
1.10 C2Hs CH3 H
1.11 n~C3H7 H H

1.12 ~ CH3 H
1.13 H CH3 H
1.14 i-C3~I7 CH3 H
1.15 i-C3H7 CH3 CH3 1.16 C(CH3)3 CH3 H
1.17 CH3 C2~s H
1.18 C~I3 C2Hs CH3 1.19 1/\ CH3 ~H3 1.20 A C2Hs CH3 .

2 ~ 11 3 7 g j ExampleH2: 2,3~4,5-Tetrahydro-3-oxo-4-amino-6-methvl-1,2.4-triazine With cooling, 210 g (1.0 mol) of 2-oxo-5-trifluoromethyl-2,3-dihydro-1,3,4-oxadiazole-3-acetone are added to 250 ml of hydrazine hydrate. The resultant clear brown solution is stirred for 2 hours and then concentrated by evaporation under vacuum. The residue is chromatographed over silica gel (elution with a 9:1 mixture of methylene chloride/methanol), and the solvent is removed by evaporation. The title compound of formula H3C~N'''NH2 (compound 2.01) H

crystallises from the residual oil after addition of ether; m.p. 117-119C (yield: 64 g;
50%).

The following compounds of formula II are prepared in analogous manner:

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Tabl~ 2:

Rl~><N ~ NH2 ~N~O
H
Compound Rl R2 R3 m.p. C
2.01 CH3 H H 117-119 2.02 CH3 CH3 H 172-174 2~03 CH3 CH3 CH3 138-139 2.04 C2Hs H H 143-145 2.05 i-C3H7 H H 79-81 2.06 C(CH3)3 H H 148-150 2.07 ~ H H 94-95 2.08 C6Hs H H 199-202 2~09 4-Cl-C6H4 H H 208-210 2.10 H H H
2.11 CH3 C2Hs H
2.12 C2Hs CH3 CH3 2.13 C2Hs CH3 H
2.14 n~C3H7 H H
2.15 n-C3H7 ~,H3 H
2.16 n~C3H7 CH3 CH3 2.17 i-C3H7 CH3 H
2.18 C(CH3)3 CH3 H
2.19 C(CH3)3 CH3 CH3 rl ~ ~

Table 2: (continuation) Compound Rl R2 R3 m.p. C

2.20 ~ CH3 CH3 2.21 /\ CH3 ~
xample H3: 2~3~4~5-Tetrahydro-3-oxo-4-r(2-methylpvTidin-3-yl)-methYleneaminol-6-methvl- 1 ,2,4-triazine To a solution of 0.5 g (4 mmol) of 2,3,4,5-tetrahydro-3-oxo-4-amino-6-methyl-1,2,4-tri-azine in 250 ml of ethanol are added, at room temperature, 0.48 g (4 mmol) of 2-methyl-pyridine-3-carbaldehyde and 1 drop of concentrated HCl. The reaction mixture is stirred for 1/2 hour and then filtered. The isolated solid is washed with ether and dried, affording the title compound of formula H3C ~ ~ N = CH <~
~N~O c~N (compound4.19) I
H

n the form of a colourless solid; m.p. 226-229C (yield: 0.6 g; 64%).
xample H4: 2.3,4.5-tetrahvdro-3-oxo-4-r(pvridin-N-oxide-3-vl)-methvleneaminol-6-methyl- 1 ,2,4-triazine To a solution of 2.56 g (0.02 mol) 2,3,4,5-tetrahydro-3-oxo-4-amino-6-methyl-1,2,4-triazine in 25 ml of ethanol are added 2.44 g (0.02 mol) of pyridine-3-carbaldehyde-N-oxide. The reac~ion mixture is refluxed for 1/2 hour, then cooled, and the precipitated solid is isolated by filtration, washed with ether and dried. The title compound of formula H3C ~ , N--CH~
N ~ ~ N (compound 4.09) O

~ ~ 37~

is obtained in the form of a white solid; m.p. 242-244C (yield: 3.6 g; 84%).
The following compounds of formula.e Ia, Ib and Ic are also prepared as described above:
Table 3:

R4~ R6 ~><N' J~N~R (Ia) H R4, Rs, R6, R7 = H, n = 0 _ Compound Rl R2 R3 PhysicEl data 3.01 CH3 H H m.p. 249-250C
3.02 C~I3 C~3 CH3 m.p. 162-163C

20~L3rl$~

Table 4:

< , N = CH~ (Ib) N ~ ~C~ R4 N R7 n _ . _ Compound R1 R4 Rs R6 R7 n Physical data _ 4.01 CH3 H H H Cl O m.p. 227-228C
4.02 CH3 Cl H Cl Cl 0 m.p. 248-249C
4.03 C2Hs H H H Cl 0 m.p. 226-227C
4.04 CH3 H H H CH3O 0 m.p. 193-196C
4.05 CH3 CH3~ H H C~3O 0 m.p. 241-243C
4.06 CH3 Cl H H H 0 m.p. 240-241C
4.07 CH3 H H H CH3 0 m.p. 220-223C
4.08 CH3 NH2 H H H O m.p. > 250C
4.09 CH3 H H H H 1 m.p. 242-244C
4.10 CH3 H H CH3 H 0 m.p. 229-230C
4.11 CH3 H CH3 H H 0 4.12 CH3 H H F H 0 4.13 CH3 F H H H 0 4.14 CH3 H H H F 0 4.1~ CH3 H F H H 0 4.16 CH3 H H H CH3S o 4.17 CH3 H H H (CH3)2N 0 4.18 CH3 CH3 H H H 1 m.p. 238-240 4.19 OEI3 OEl3 H H H O m.p.226-229C

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Table 4: (continuation) Compound Rl R4 Rs R6 R7 n Physical data 4.20 CH3 SCH3 H H H 0 m.p. 255C
4.21 C4Hg(t) H H H H 1 m.p. 129-132C
4.22 C3H7(i) H H H H 1 m.p. 120-121C

Table 5:

~l ~ ~o~ N (Ic) H

Compound Rl R2 R3 Physical data _ _ .

5.01 CH3 H H m.p. 242C
5.02 (CH3)2CH H H m.p. 168-170C
5.03 CH3 CH3 CH3 m.p. 234-235C

Example 2: Formulation Examples Formulations for compounds of formula I or combinations thereof with other insecticides or acaricides (throughout, percentages are by weight) Fl. Wettable powders a) b) c) compound of formula I or combination 25 %50 % 75 %
so~iumligninsulfonate 5 % 5 %
sodium laurylsulfate 3 % - 5 %
sodium diisobutylnaphthalenesulfonate - 6 % 10 %
octylphenol polyethylene glycol ether (7-8 mol of ethylene oxide) - 2 %
highly dispersed silicic acid 5 % 10 %10 %
kaolin 62 % 27 %

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The active ingredient or combination is thoroughly mixed with the adju~/ants and the mixture is thoroughly ground in a suitable mill, affording wettable powders which can be diluted with water to give suspensions of the desired concentration.

F2. Emulsifiable concentrate compound of forrnula I or combination10 %
octylphenol polyethylene glycol ether (4-5 mol of ethylene oxide) 3 %
calcium dodecylbenzenesulfonate 3 %
castor oil polygycol ether (36 mol of ethylene oxide) 4 %
cyclohexanone 30 %
xylene mixture 50 %

Emulsions of any required concentration can be obtained from this concentrate by dilution with water.

F3. Dusts a) b) compound of formula I or combination 5 % 8 %
talcum 95 %
kaolin - ~2 %

Ready for use dusts are obtained by mixing the active ingredient with the carrier, and grinding the mixture in a suitable mill.

F4. Extruder ~ranulate compound of formula 1 or combination10 %
sodium ligninsulfonate 2 %
carboxymethylcellulose 1 %
kaolin ~7 %

The active ingredient or combination is mixed and ground with the adjuvantsf and the mixture is subsequently moistened wi~h water. The mixture is extruded and then dried in a stream of air.

3 ~ ~ ~

FS. Coated ~ranulate compound of formula I or combination 3 ~o polyethylene glycol (mol.wt.200)3 %
kaolin 94 %

The finely ground active ingredient or combination is uniformly applied, in a mixer, to the kaolin moistened with polyethylene glycol. Non-dusty coated granulates are obtained in this manner.

F6. Suspensis~n concentrate compound of formula I or combination 40 %
ethylene glycol 10 %
nonylphenol polyethylene glycol ether (15 mol of ethylene oxide) 6 ~o sodium lignosulfonate 10 %
carboxymethylcellulose 1 %
37 % aqueous formaldehyde solution 0.2 %
silicone oil in the form of a 75 %
aqueous emulsion 0.8 %
water 32 %

The finely ground active ingredient or combination is intimately mixed with the adjuvants, giving a suspension concentrate from which suspen- sions of any desired concentration can be obtained by dilution with water.

3. Biological Examples Example B~1: Contact action a~ainst Aphis craccivora Before ~he start of the test, 4- to S-day-old pea seedlings (Pisum satirum) reared in pots are each populated with about 200 insects of the species Aphis craccivora. The treated plants are sprayed direct to drip point 24 hours later with an aqueous formulation containing 400 ppm of the test compound. Two plants are used for each test compound, and a morta-lity count is made after a further 24 and 72 hours. The test is carried out at 21-22C and a relative humidity of about 55 %.

Compounds according to Tables 3, 4 and 5 exhibit good activity in this test.

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Example B.2: Systemic action against Myzus persicae Pimenta plants are in~ected with well populated pea seedlings. The soil is treated 4 days later with 25 ml of a 0.1% spray mixture prepared from a 10% emulsifiable concentrate and water, such that the concentration of test compound in the soil is 12.5 ppm (amount by weight, based on the volume of the soil). The plants are enveloped in a paper frill.

Evaluation of mortality is made 3 and 7 days after the start of the test. Two plants, each in a separate pot, are used for each test compound. The test is carried out at 25C and ca.
65% relative humidity.

After 1, 2 and 4 weeks the plants are populated anew and fresh mortality counts are made after 3 and 7 days following treatment.

Compounds according to Tables 3, 4 and 5 exhibit good activity in this test.

Example B.3: Contact action a~ainst Mvzus persicae. direct sPraY test 4 days before treatment, pipmenta plants (in the 6-leaf stage, in pots) are infested with a population of Myzus persicae (R strain) by placing pea seedlings 2-3 cm long and well populated with aphids on the pimenta plants. As soon as the pea seedlings begin to wither, the aphids migrate onto the test plants (pimenta). The treated plants are sprayed direct to drip point 24 hours later with an aqueous suspension prepared from a 25 % wettable powder, containing 100 ppm of the test compound. Four plants are used for each test compound. A mortality count is made 7 days after application. The test is carried out at 21-22C and ca. 60 % relative humidity.

The compounds according to Tables 3, 4 and 5 exhibit good activity in this test. In particular, compound 4.09 effects over 80 % kill.

Example B.4: Test of lon -term action a~ainst MYZUS ~sicae Peperoni plants (in the 6-leaf stage, in pots) are treated by spray application with the test solutions and, 2 days after the treatment, the test plants are infested with a population of Myzus persicae (R strain) as described in ~xample B.3. An evaluation of the percentage mortality is made S days after populating the plants.

7 ~ ~

The compounds according to Tables 3, 4 and 5 exhibit good activity against myzuspersicae in this test. In particular compound 4.09 effects over 8() % kill.

Example B.5: Contact action against Bemisia tabaci Bean plants in pots (Phaseolus vulgaris, Autan variety) are populated in the 2~1eaf stage with Bemisia tabaci (40 adults per plant). After a 3-day period for oviposition, the adults are removed. Ten days after population, when ca. 2/3 of the nyrnphs are in the late first nymphal stage and 1/3 are already in the second nymphal stage, the plants are treated in a spray chamber with a spray mixture (prepared from a 10% emulsifiable concentrate and water) in different concentrations.

A count of dead nymphs, pupae and adults of the Fl generation is rnade 24 days after population. The test is carried out at 25C and 50-60% relative humidity.

Compounds according to Tables 3, 4 and 5 exhibit good activity at a concentration of 3 ppm. In particular, compound 4.09 effects over 80% kill.

Claims (21)

1. A compound of formula I
(I) wherein R1 is C1-C12alkyl or C3-C7cycloalkyl, R2 and R3 are each independently of the other hydrogen or C1-C6alkyl, R4, R5, R6 and R7 are each independently of one another hydrogen, halogen, C1-C3alkyl, , C1-C3alkoxy or C1-C3alkylthio, and n is 0 or 1, or a salt thereof, with the proviso that n is 1, if simultaneously the pyridine ring is attached via the 3-position to the methylidene group and R4, R5, R6 and R7 are each hydrogen.

2. A compound of formula I according to claim 1, wherein R1 is C1-C4alkyl.

3. A compound of formula I according to claim 1, wherein R1 is methyl, ethyl, isopropyl or cyclopropyl.

4. A compound of formula I according to claim 1, wherein n is 1.

5. A compound of formula Ia according to claim 1 (Ia) wherein R1 to R7 and n are as defined in claim 1.

6. A compound according to claims 1 or 5, wherein R2 and R3 are each independently of the other hydrogen or methyl.

7. A compound according to claims 2 or 3, wherein R2 and R3 are each independently of the other hydrogen.

8. A compound of formula Ib according to claim 1 (Ib) wherein R1, R4 and R7 and n are as defined in claim 1.

9. A compound according to any one of claims 1, 3 or 8, wherein R1 is methyl or ethyl, R5 is hydrogen, R4, R6 and R7 are each independently of one another chloro, methyl, methoxy or amino.

10. A compound according to any one of claims 1, 3 or 8, wherein R6 is hydrogen.

11. A compound according to any one of claims 1, 2 or 3, wherein R4, R5, R6 and R7 are each hydrogen and n is 1.

12. A compound according to any one of claims 1, 5 or 8, wherein R1 is methyl.

13. A compound according to claim 8, wherein R4, R5 and R6 are each independently of one another methyl or fluoro, R7 is hydrogen, methylthio or dimethylamino, and n is 0.

14. A compound of formula Ic according to claim 1 (Ic) wherein R1, R2 and R3 are as defined in claim 1.

15.2,3,4,5-Tetrahydro-3-oxo-4-[(pyridin-N-oxide-3-yl))-methyleneimino]-6-methyl-1,2,4-triazine of formula according to claim 12.

16. A process for the preparation of a compound according to claim 1 of formula I
(I) or of a salt thereof, which process comprises reacting an aminotriazinone of formula II
(II) wherein R1 is C1-C12alkyl or C3-C7cycloalkyl, R2 and R3 are each independently of the other hydrogen or C1-C6alkyl, with an aldehyde of formula III

(III) wherein R4, R5, R6 and R7 are each independently of one another hydrogen, halogen, C1-C3alkyl, C1-C3alkoxy or C1-C3alkylthio, and n is 0 or 1, with the proviso that n is 1, if simultaneously the pyridine ring is attached via the 3-posidon to the methylidene group and R4, R5, R6 and R7 are each hydrogen, and, if desired, converting the resultant compound of formula I into a salt thereof.

17. A pesticidal composition which contains, as active component, a compound of formula I as claimed in claim 1, together with suitable carriers and/or adjuvants.

18. A method of controlling pests, which comprises contacting or treating said pests, their different development stages or the locus thereof, with a pesticidally effective amount of a compound of formula I as claimed in claim 1 or a salt thereof, or with a composition containing a pesticidally effective amount of such a compound in addition to carriers and adjuvants.

19. A method according to claim 18, wherein the pests to be controlled are insects and arachnids.

20. A method according to claim 19, wherein the pests to be controlled are plant-injurious insects.

21. A method according to claim 20, wherein the pests to be controlled are sucking insects.