CS208686B2 - Insecticide and acaride means - Google Patents

Abstract

1,268,000. Benzimidazoles. ELI LILLY & CO. 2 May, 1969 [3 May, 1968], No. 57613/70. Divided out of 1,267,998. Heading C2C. Compounds of formulae wherein Y is hydrogen or fluorine and Z is hydrogen, fluorine, chlorine, -CF 3 or -CF 2 CF 3 , are prepared by cyclization of a corresponding o - phenylene diamine by heating with a compound of formula Z-CF 2 -COOH. The products have insecticidal and acaricidal activity. 3 - Nitro - 5 - trifluoromethyl - o - phenylene diamine is prepared by reaction of 2,6-dinitro- 4 - trifluoromethyl - 1 - chlorobenzene with ammonium hydroxide to give 2,6-dinitro-4-trifluoromethylaniline, followed by reaction of this with ammonium polysulphide. Reference has been directed by the Comptroller to Specifications 1,087,561 and 1,159,789.

Description

Benzimidazoles are known to be useful in controlling parasites in mammalian and avian bodies. It has further been found that 2-trifluoromethylbenzimidazoles are useful as herbicidal, nematicidal and insecticidal agents, as well as mollusc control agents. (British Patent No. 1,087,581, U.S. Patent No. 3,412,101, South African Patent No. 65/5584, and Dutch Patent No. 67/13786 are given as examples).

The 2-trifluoromethyl derivatives most commonly used as insecticides are substituted in the benzene moiety of the benzimidazole ring system by a chlorine atom and nitro groups, the most active compounds being 2-trifluoromethyl-4,5,6,7-tetrachlorobenzimidazole, 2-trifluoromethyl-5,6 -dichlorobenzimidazole and phenyl-2-trifluoromethyl-4-nitro-6-chloro-1-benzimidazolecarboxylate.

Said compounds generally have the greatest activity against Lepidoptera, such as Prodenia eridania, and Diptera, such as house flies and mosquitoes.

For example, 2-trifluoromethyl-4,5-dichlorobenzimidazole completely destroys the Prodenia eridania larvae at a dose of 250 ppm, but does not act at the same concentration against Oncopeltus fasciatus, cockroach and flowering insects, and its efficacy against domestic flies is excellent only at 1100 ppm.

The isomeric compound, 2-trifluoromethyl-5,6-dichlorobenzimidazole has the same excellent activity against Prodenia eridania larvae at a concentration of 250 ppm, but no activity at the same concentration against Oncopeltus fasciatus, cockroach and flowering as well as house flies. benzimidazoles, in their absolute activity, do not approach organic phosphoric insecticides or have a broad spectrum of activity.

Two large groups of marketed insecticidal agents that are widely used and have a broad spectrum against many low-dose insects are organic phosphorus compounds and chlorinated hydrocarbons.

Many of the most active organic insecticidal phosphorus compounds are extremely toxic to humans and their toxicity by intradermal absorption is of the order of magnitude as high as inhalation toxicity.

These very toxic compounds are therefore extremely dangerous in handling, even when using a gas or oxygen mask. The safest of the phosphate insecticides malathion is still widely used, but its spectrum of action is not as broad as would be desirable and many insect or mite species have become resistant to their action for many years.

Defects of chlorinated hydrocarbons are of a different nature. However, it outweighs the resistance to their action, but this problem is not as serious as one might expect, given the infinite number of new chlorinated hydrocarbons produced.

The main disadvantage of chlorinated hydrocarbons is that they remain in soil and water for many years, which is mainly attributed to their stability to metabolism. This perseverance has now begun to adversely affect other life forms, including birds and fish.

There is therefore a need for compounds that have both insecticidal and acaricidal activity and which have a broad spectrum of activity, are safe to handle and do not remain decomposed.

Accordingly, the present invention provides an insecticidal and acaricidal composition comprising, as active ingredient, a benzimidazole of formula Ia or Ib, or a benzimidazole sodium salt of formula Ia or Ib, or

wherein R is a hydrogen atom, a group

group

R group R-Oskde

R 'is hydrogen or nitro; and

R is C 1 -C 6 alkyl or allyl,

R 'and R ** each represent a hydrogen atom, methyl, ethyl or phenyl, or together with the nitrogen atom to which they are attached form a piperidine ring and

Y is a fluorine or hydrogen atom,

Z is a fluorine, hydrogen or chlorine atom or a -CF3 group or a group wherein the halogen atom mentioned above is an atom having an atomic number below 36.

The invention further relates to a process for the preparation of the benzimidazole compounds of the above formulas, wherein the alkali metal salt of the benzimidazole of the formula IIa and IIb is reacted.

AND

M (Ila)

(IIb) wherein M is an alkali metal atom and Y and Z are as defined above, with a compound of formula R-halogen, wherein R and halogen are as defined above.

The invention also relates to a process for preparing a benzimidazole compound of formula IIIa and IIIb

(lila)

(IIIb) wherein Y is fluorine or hydrogen, and when Y is hydrogen, Z is fluorine, hydrogen, chlorine, or -CF-CF ₂ -CF ₃ and when Y is fluorine, Z is hydrogen, chlorine, CF or a group -CF ₂ -CF?

3 '

(IV) where

Y is as defined above, together with an acid of formula

Z-C-OH

Wherein Z is as defined above.

The composition of the invention is used for controlling insects and mites by applying the above insecticidal and acaricidal composition to insect or mite habitats.

When R is hydrogen in the above formulas, benzimidazole exists in two tautomeric forms, one being (when Y and Z are fluorine atoms) 2,6-bis (trifluoromethyl) -4-nitrobenzimidazole and the other is 2, 5-bis (trifluoromethyl) -7-nitrobenzimidazole.

206686

Both of these structures are in equilibrium in any pure compound. When the hydrogen atom on the benzimidazole nitrogen is replaced by a phenylsulfonyl, carboxyl, thiocarboxamide or other group within the limits of R as defined above, there is no longer the possibility of tautomerization and each of the N-derivative compounds contains a mixture of two substances, one of which for example using 2,6-bis (trifluoromethyl) -4-nitro-1-phenylsulfonylbenzimidazole and the other 2,5-bis (trifluoromethyl) -7-nitro- 1-phenylsulfonylbenzimidazole.

Only one of these isomers can be readily isolated. Thus, it is to be understood that the present invention encompasses both 4-nitro-6-fluoro-ethyl-2-fluoroalkylbenzimidazoles substituted at the 1-position as 7-nitro-5-fluoromethyl-2-fluoroalkylbenzimidazoles substituted at the 1-position.

When using the compositions according to the invention, the insecticidal or acaricidal amount of benzimidazole of the above formulas Ia and Ib is applied to a place where insects or spider insects live, such as foliage or other parts of a living plant, if shallow mites, insects of the order Hemiptera (Oncopeltus fasciatus) or similar insects, or applied to soil in which a useful plant is grown, such as where insect-attacking roots and the like are to be controlled. The insect site may also be the wall of a building if flies or mosquitoes are to be combated.

The benzimidazole of the above formula can be applied to a spider or other insect in its habitat in pure form or in a relatively pure form, if desired, that is unmixed with other ingredients.

However, this method of administration is a waste, since the compounds are active at extremely low concentrations, as will be discussed below. Therefore, the insecticidal and acaricidal properties of 2-fluoroalkyl-6-fluoromethyl-4-nitrobenzimidazoles and their N-derivatives are advantageously utilized by using a preparation containing benzimidazole as an active ingredient dispersed in a suitable inert carrier together or without other compatible ingredients with fungicidal, bactericidal, insecticidal or herbicidal properties.

Formulations containing benzimidazole are best formulated as emulsifiable concentrates or dusts, although granular formulations or wettable powders may be used.

Compounds which are used for direct spraying or dusting on insects or arachnid insects in its habitats are prepared by known methods such as mixing benzimidazole with a non-phytotoxic diluent, such as water, accompanied by a surfactant to form an emulsifiable concentrate, such as clays, bentonites, silica, hydrated aluminum oxide,? kieselguhr or diatomaceous earth to form a dustable powder or wettable powder in which a surfactant is included or combined with one of the materials just mentioned followed by compression of the resulting mixture to form a granular formulation.

Dusting powders and granular formulations are generally used in this state, whereas wettable powders and emulsifiable concentrates are first prepared as a concentrate and then diluted with a non-toxic agent before use.

The benzimidazole active as insecticide is usually present in the diluted powder or spray at a concentration of between about 0.0025% to about 5%, preferably between 0.01 to 0.6%.

The concentration of benzimidazole in the concentrates used to prepare wettable powders or emulsifiable concentrates is necessarily considerably higher and may range from 5 to 90% if desired. The above insecticidal compositions are applied to insect or spider insect sites by spraying or spraying guns or other similar devices.

However, the amount of benzimldazole to be applied for the purpose of killing insects or arachnid insects in a given plant compartment depends on a number of factors such as dew, the vegetation area to be covered, the severity of the insect attack, the foliage being treated, temperature, moisture, etc. In general, between 0.11 and about 5.5 kg of benzimldazole per hectare of insect infested plant organism is used.

Applying to the foliage of the plant up to a level of about 0.01 to 0.6% in water based on the weight / volume of benzimldazole effectively affects life in terms of insecticidal or acaricidal effects.

As an alternative, effective insecticidal or acaricidal protection provides a light but complete dusting of the plant with a pulverulent mass containing about 0.01 to 0.6 weight percent of benzimldazole.

The benzimidazoles of the invention may also be formulated to contain other insecticidal agents. These include rotenone, natural or synthetic chrysanthemic acid esters or related substances including pyrethine and allethrin, chlorinated hydrocarbons including substances such as BHC, lindane, chlordane, heptachlor, toxaphene, aldrin, dieldrin, endrin, DDT, TDE and methoxychlor, organic compounds phosphorus including TEPP, phosphoramides, demeton, malathion, ethion, dimethoate, mecarbam, methylparathion, parathion, OT2,4-dichlorophenyl-O-methylisopropylphosphoramidothioate, ronnel, 0-4-tert-butyl-2-chlorophenyl-0-methylmethylphosphoramidate, tepa, metepa, diazinone and metasistox, sulfites including 2- (p-tert-butylphenoxy) -1-methylethyl-2-chloroethylsulfite and carbamates including 4-dimethylamino-3,5-xylylmethylcarbamate and carbaryl.

Formulations useful in the process of the invention include the following:

I. Wettable powder of% 2, .alpha.-bis- (trifluoromethyl) -4-nitrobenzimidazole, 70.5% of kaolin, 3% of alkylaryl polyether alcohol and 1.5% of sodium lignin sulfonate.

II. Granule

The impregnation solution was prepared from 6 parts of 2,6-bis- (trifluoromethyl) -4-nitrobenzimidazole mixed with 4 parts of ethylene glycol monomethyl ether. 17.2 g of this solution are sprayed onto 82.8 g of diatomaceous earth and the mixture is compressed into grains containing 10% of active ingredient.

III. Granule

The impregnation solution was prepared from 6 parts of 2,6-bis- (trifluoromethyl) -4-nitrobenzimidazole sodium salt and 4 parts of water. 17.2 g of the solution are sprayed onto diatomaceous earth in the same manner as in the previous case, and the sprayed substance is compressed into granules containing 10% of the active substance.

IV. Dusting a portion of 2,6-bis- (trifluoromethyl) -4-nitrobenzimidazole is mixed with 99 parts of talc after finely grinding both components to pass through a No. 325 sieve.

The benzimidazoles of formulas Ia and Ib have a very broad insecticidal and acaricidal spectrum. The compounds are particularly active against insects of the order Coleoptera, both against larvae and against adult forms of Epilachna varivestis, pilouse, cleaver,

Oulema melanopus, Epitrix cucumeris, Megacyllene robiniae, Colorado potato beetle, Darkling beetle, Hypera punctata, Skin beetle, Oryzaephilus surinaj ^ ensis, Lyctus spp. , · Smith,

Sitophilua oryzae, Nodonota puncticollis, Conotrachelus nenuphar and Phyllophaga spp.

б

The 2-fluoroalkyl-6-fluoromethyl-4-nitrobenzimidazoles and their N-derivatives are also extensively effective against Hemiptera insects including aphid species such as shallow cotton, pink club, Trialeurodes vaporariorum, Toxoptera graminum, Rhopalosiphum maidis, green club Bloody Swallowtail, Thistle, Peach Aphid, Therioaphis maculata, Aphis spiraecola, Shallow Poppy.

The compounds also have excellent acaricidal activity and are effective against Paretetranychus pilosus (at a concentration of 10 ppm or less), Briobia pretiosa, Phyllocoptruta oleivora, Panonychus citri, mites and ticks.

These compounds are also active against Heteroptera insects such as Oncopeltus fasciatus, Ligus lineolaris, Leptocoris trivittatus, bed bugs, Anasa tristis and Hilsus leucopterus, against Diptera insects such as house fly, mosquito-transmitting mosquito, and species such as stinging thistle , Haematobia iritans, flower beetle, carrot grass, Lepidoptera such as Prodenia eridania, apple beetle, blacksmith, moth, argyroteemia velutinana, Heliothis zea, corn borer, Trichoplusia ni, Thyridusopterix ephemera, Thyridusopterix ephemera, Thyridusopterix, and Thyridusopterix .

Finally, the compounds have proven activity against cockroaches, the order of Orthoptera, at doses comparable to those used in today's common insecticides for controlling cockroaches.

The insecticidal and acaricidal activity of the compounds according to the invention is demonstrated by the following tests against representative insects and mites.

Trial stupid

Coleoptera

Cuttings Four six-day Bountiful snap bees containing two leaves with approximately 6.5 cm ² of leaf surface are placed in water. Spray the leaves with 5 to 10 ml of the preparation containing a predetermined amount of the test substance.

Half of the formulation is sprayed onto the upper surface of the sheet using a DeVilbiss sprayer at a pressure of 69 kPa from a distance of about 46 cm from the flight. When the leaves have dried, they are cut off from the stalk and placed separately in petri dishes.

Ten individuals in the third developmental stage of non-chewing larvae of Epilachna varivestic grown on beans are placed on individual leaves. Control samples are two leaves sprayed with 5 ml of a formulation containing 500 ppm malathion (reference sample), two leaves are sprayed with the formulation without the active ingredient and two leaves are kept as controls without treatment. After 48 hours, the number of deaths and the number of survivors were counted. Dying larvae count as dead. This rating scale shall apply.

Percentage of death 0 to 10 Rating 0 11 to 20 1 21 to 30 2 31 to 40 3 41 to 50 4 51 to 60 5 61 to 70 6 71 to 80 7 81 to 90 8 91 to 100 9

Prodenia eridania (Lepidoptera) larvae Prodenia eridania of the same appearance in length of 1 to 1.5 cm, grown on lima beans, variety Henderson, is placed on the cut bean leaves in Petri dishes. The obtained leaves were sprayed with the insecticidal preparation in the same manner as in the previous case in Test 8 Epilachna varivestis.

The reference control samples in this case are the leaves sprayed with 5 ml of DDT solution containing 100 ppm DDT. The deaths counted 48 hours after spraying and the dead larvae were counted among the dead. Missing larvae are considered living. The same assessment was carried out as in the previous case.

Aphis gossypii (Hemiptera) four seeds of the pumpkin Blue hubbard squash are planted in a container containing vermiculite and the containers are irrigated from below. After six days, the two weakest plants are cut off and the uterus and first leaves are removed from each of the remaining two plants.

The remaining uterus is infected with 100 individuals of the Aphis gossypii aphid from the baseline colony by laying the uterus against the infected uterus of the same plant and allowing aphid transmission. After transfer, the leaf is removed from the colonies.

After 48 hours, the infected leaves are sprayed so as to be wet-coated with preparations containing an increased amount of insecticide using a DeVilbiss sprayer at a pressure of 69 kPa from a distance of 30 to 40 cm from the plant. *

Control samples consist of two infected and sprayed plants and two infected plants sprayed to complete wetting with a formulation containing 100 ρρψ malathion as the reference standard.

Death was estimated 24 hours after spraying by observation using a tenfold magnification microscope used for histological purposes. The evaluation was carried out as in the previous case.

Tetranychus urticae

The procedure is the same as in the previous aphid experiment 8 except that 100 individuals from the basic colony grown on the plants of the above pumpkin are transferred to the cut uterus of said plant.

Death is estimated 48 hours after spraying. The same assessment method shall be used.

Oncopeltus faeciatuB (Hemiptera) in adults is kept cold and placed in a test cage. Individual cages are sprayed with 5 ml of a test preparation containing a certain amount of insecticidal agent in advance using a DeVilbiss sprayer at a pressure of 69 kPa from a distance of 30 cm from the top of the cage.

When the cage has dried, individuals are fed and watered for 48 hours. A 500 ppm malathion formulation was used as the reference sample and two non-sprayed cages as control samples. Deaths add up 48 hours after spraying. Dying adult individuals count as dead. The same rating as above applies.

206666

Musea domestica (Diptera) (House Fly)

A. Contact test.

Fly cages containing four-day adult house flies are cooled to 2-4 ° C for one hour. 2 sprouts were transferred with 100 flies for each test sprout using a small spoon.

Flies in the cages are kept for one to two hours at 21 to 27 ° C. The cages are sprayed in the same way as Oncopeltus fasciatus with 5 ml of the test product. Two unsprayed cages are kept as controls and two 50 ρρψ cages containing DDT in this quantity are sprayed as a reference sample.

Dead counts are performed 24 hours after spraying. All flies that do not fly or crawl from the bottom of the cage are considered dead. The same evaluation shall be carried out as in the previous cases.

B. Digestive organ test.

Ten chilled house flies are removed from the cage in which they are grown and placed in a covered petri dish. An hour after the flies have been removed from the refrigerated compartment, a cube of sugar containing 0.2 ml of the formulation containing the specified amount of insecticide is placed in a petri dish.

Control samples are treated to contain sugar cubes with 0.2 ml deionized water and cubes containing 0.2 ml of a 500 ppm malathion formulation. Deaths are counted after 24 hours, using the same assessment method as above.

Blatta orientali8 (Orthoptera) (Eastern Cockroach)

The pan containing the cockroaches in late form (3-4 months old) is placed in the refrigerated compartment for approximately one hour. Ten larvae are removed from the pan and placed in the cages and the insects in the cages are kept at 21 to 27 ° C for one hour.

The test cages were then sprayed as described above with Oncopeltas fasciatus using 5 ml of the formulation containing the specified amount of insecticidal substance.

The test cages are maintained for 72 hours, during which time cockroaches are not fed or water is supplied. Control samples consist of two non-sprayed, two product-only and two spray ppm containing 1000 ppm heptachlor.

Counting of the dead individuals is performed 24 hours after spraying with slight shaking of the sprouts. All cockroaches remaining at the bottom are counted as dead individuals.

Anthonomus grandis (Coleoptera) (Flowerpot)

The procedure is the same as that used for Epilachna varivestis and Prodenia eridania, except that ten individuals of the flora are placed on cotton leaves soaked in preparations containing the test compounds. The same assessment method shall be used.

Test results

The tables below show the effect of selected compounds of the invention on the above mentioned species of insects and mites. In each of the following tables, the test compound is indicated by the letter of the assembly that follows.

And 2,6-bis (trifluoromethyl) -4-nitrobenzimidazole

В sodium _2> 6-bis (trifluoromethyl) -4-nitrobenzimidazole

C mixture of 2,6-bis (trifluoromethyl) -4-nitro-1-benzimidazolecarboxylic acid benzyl ester and 2,5-bis (trifluoromethyl) -7-nitro-1-benzimidazolecarboxylic acid benzyl ester D 2,6-bis (trifluoromethyl) methyl ester ) -4-Nitro-1-benzimidazolecarboxylic acid and 2,5-bis (trifluoromethyl) -7-nitro-1-benzimidazolecarboxylic acid methyl ester 2,6-Bis (trifluoromethyl) -4-nitro-1-benzimidazolecarboxylic acid n-hexyl ester F 2,6-bis (trifluoromethyl) -4-nitro-1-phenylsulfonylbenzimidazole

G 2,6-Bis (trifluoromethyl) -4-nitro-1-benzimidazolecarboxylic acid ethyl ester

H mixture of 2,6-bis (trifluoromethyl) -4-nitro-1-benzimidazolecarboxylic acid phenyl ester and 2,5-bis (trifluoromethyl) -1-benzimidazolecarboxylic acid phenyl ester

2,6-Bis (trifluoromethyl) -4-nitro-1-benzimidazolecarboxylic acid isopropyl ester

2,6-Bis (trifluoromethyl) -4-nitro-1-benzimidazolecarboxylic acid allyl ester L 2-chlorodifluoromethyl-4-nitro-6-trifluoromethylbenzimidazole

M 2-Trifluoromethyl-4-nitro-6-difluoromethylbenzimidazole

4-Nitro-2,6-bis (trifluoromethyl) -1-benzimidazolecarboxylic acid p-nitrophenyl ester 0 A mixture of N-ethyl-4-nitro-2,6-bis (trifluoromethyl) thio-1-benzimidazolecarboxanilide and N-ethyl-7 -nitro-2,5-bis (trifluoromethyl) thio-1-benzimidazolecarboxanilide

P is a mixture of N, N-dimethyl-4-nitro-2,6-bis (trifluoromethyl) thio-1-benzimidazolecarboxamide and N, N-dimethyl-7-nitro-2,5-bis (trifluoromethyl) thio-1-benzimidazolecarboxamide.

The following tables list the type of insect or mite as test organism in the heading. Column t of the table lists the code number for the test compound and Column 2 and the others give an average rating using the above scale for a rating of 0 to 9 with decreasing concentrations initially of 1000 ppm to the amount where the insecticidal formulation virtually ceases to be active.

One or more standard insecticidal products are listed for each test case.

Table 1

Test for Epilachna varivestis

Evaluation in ppm

Compound 1 000 500 250 100 ALIGN! 50 25 10 5 AND 9 9 9 9 9 9 9 7 В 9 9 9 9 8 6 7 2 C 9 9 9 9 9 - - - D 9 9 9 9 9 9 9 0 E 9 9 9 9 5 7 7.5 2.5 F 9 9 9 9 9 8 7 0 G 9 - - - - - - H 9 9 9 9 7 3 4 - AND 9 9 9 9 9 6.5 8 0 К 9 - - - - - - - L - 9 9 9 8.5 9 7 4 M 9 7.5 9 5.5 1.5 - - -

Ratings in ррш

Compound 1,000 500 250 100 25 10 5

N 9 9 9 9 9 7 4 - 0 9 9 9 6.5 5.5 6 1 »5 - P Malathion 9 8.5 7 to 8 7.5 7 4,5 0 0 -

Table 2

Test for Prodenia eridania

Compound AND 1 000 evaluation in ppm 100 ALIGN! 500 250 AND 9 6 3 В 9 4 3 0 C 7 6 - 2 D 1 - - - E 7.5 5.0 2 0 F 4 0 - - G 6  - - - H 1 1 1 - AND 8 6 4 0 К 6 - - - L - 3.5 - - M 8 1.5 - - P 0.5 0 0 - DDT 7

^T able 3

Aphis gossypis exam

Hfffoffff.gnX X ДР &

Compound 1 000 500 250 100 ALIGN! 50 25 10 5 AND 9 8 8 7 5 1 0 - В 9 9 8 7 7 8 9 0 C 8 9 5 0 - - - - D 9 9 9 4 2 0 - - E 9 9 9 9.5 8 7 7 1.5 F 9 9 9 8 2 0 - - G 9 - - - - - ~ - - - H 6 8 7 8 4 0 - - AND 9 9 6.5 8 8.5 6 3 0 К 9 - - - - - - - L - 9 9 9 6 5.5 0 - M 9 9 9 7 0 - - - N 9 9 7.5 1 0 - - - P 4,5 7.5 7 4 - 1.5 0 Malathion 8

Table 4

Test for Tetrachynua urticae

Hpqnopetá ▼ ppm

Compound 1 000 500 250 100 ALIGN! 50 25 10 5 2.5 1 AND 9 9 9 9 9 8 8 5 - - В 9 9 9 9 9 8.5 6 5 1 - C 9 9 9 9 9 7 8 - - - D 9 9 9 6 9 4 3 - - - E 9 9 9 9 8 9 8.5 0.5 - - F 9 9 9 9 9 9 6.8 7.5 - 6.3 G 9 - - - - - - - - - H 9 9 9 9 8 2 5.5 - - - AND 9 9 9 9 9 8 8 0 - 0 к 9 - - - - - - - - - L 9 9 9 9 9 8 7.5 - 0 M 9 9 6.5 6.5 1 - - - - - N 9 6.5 6 8 8 9 6 1.5 - 2.5 0 5 - - - - - - - - - P 9 9 6.5 7.5 7.0 6 4 4 - 3 Aramite < 7 to 9

Table 5

Test for Oncopeltis fasciatus

Compound 1 000 500 250 100 ALIGN! 50 25 10 AND 9 9 9 7 4 4 5 В 9 9 9 2 2 1 - C 9 8.5 8 - 7 0 0 D 9 9 9 8 - 5 - E 9 9 8 4 1.5 6.5 0.5 F 9 9 9 7.5 6 0 0 G 9 - - - - - - H 9 9 1 - - - - AND 8 9 9 8 1 0 z 0 К 9 - - - - - L - 9 9 4,5 6 0 0 M 9 9 9 3.5 0.5 - - N 8 9 9 7 1 0 0 0 1 - - - - - - P 2 4 4 4,5 3.5 0 0 Malathion 7 to 8

10

208686 i 12 Table 6 Housefly (contact exam) Evaluation in ppm Compound 1 000 500 250 100 50

AND 9 9 9 9 8 8 4 В 9 9 9 9 8.5 3 3 C 9 9 9 5.5 4 0 0 D 9 9 9 9 9 0 0 E 9 9 9 4 1.5 8 4,5 F 9 9 9 9 9 0 0 G 9 - - - - - - H 9 9 9 9 7 7 3 AND 9 9 9 9 9 6 5 К 9 - - - - - - L - 9 9 9 9 9 1 M 9 9 9 9 9 9 8.5 N 9 9 9 9 9 8 and 0 7 9 9 8 8 8.5 6.5 P 9 9 9 9 9 8.5 4.0 DDT 6 to 8

Housefly - Exam in the digestive tract

Evaluation in ppm

Compound 1 000 500 250 100 ALIGN! 50 25 1 1 AND 9 9 9 7 2 - В 9 9 9 9 4 1 - - C 9 4 0 - - - - - D 8.5 5.5 2 - - - - - E 9 9 8 7 1 - - - F 9 . 9 1 - - - - - G 0 - - - - - - - H 9 - - 0 - - - - AND 9 - 9 9 6 0 - К 9 - - - - - - • L 9 9 7 0.5 - - - M 9 - - 5.5 0 0 0 - N 9 9 9 0 0 - - - 0 1 - - - - - - - P - 9 7 3 0 - - - Malathion 6 to 7

Evaluation in ppm

Table 8

Test for BLatt oriente! Is

Compound 1 000 500 250 100 ALIGN! 50 25 11 AND 7 4 5 0 __ 0 9 6 2 3.5 1 0.5 0 C 9 1.5 0.5 3 1.5 - - D 9 9 5.5 0 0 - - E 9 8.5 2 2 0 - - F 8 4 3 0 0 - - G 5.5 - - - - - - H 5 6.5 7 0.5 0 - - AND 9 6.5 5.5 1.5 0 - - К 9 - - - - - - L - 5.5 1 0 0 - - M 9 1.5 0 - - - - N 5.5 4,5 0 0 0 - - 0 0 - - - - - - P 8 9 5.5 2.5 0 - - Heptaehlor 8 to 9

Table 9

Test for Anthonomus grandis 250 Rating in oom Compound 1 000 500 100 ALIGN! 50 25 10 5 AND 9 9 9 9 8.5 8.8 6.7 7 _; В 9 9 8.5 9 9 8.5 6 6 C 9 9 9 9 7 8.5 4,5 - D 9 9 9 9 9 8.5 5.5 0 E 9 9 9 9 9 6.5 8 2 F 9 9 8.5 9 6.5 7.5 4 .. - G 9 - - - - - - - H 9 9 9 9 8 5.5 1 - AND 9 9 9 7.5 8.5 8.5 8 6 К 9 - - - - - - - L - 9 9 9 9 1.5 0.5 - M 7.5 8.5 8.5 5 1.5 - - - N 9 - - - - 3.5 1.5 - 0 9 9 8.5 8 7.5 6.5 0 - P 9 9 9 9 8 5 1.5 -

bíalathion 7 to 8

The compounds useful as insecticides of the invention are prepared as follows:

Preparation of a representative starting material 2,6-bis- (trifluoromethyl) -4-nitrobenzimidazole.

A solution of 40.5 g of 2,6-dinitro-4-trifluoromethyl-1-chlorobenzene in 300 ml of benzene is treated with 250 ml of 14 N ammonium hydroxide solution. The reaction mixture was stirred at room temperature for 1.5 hours, then an additional 100 mL of 14 N ammonium hydroxide was added and stirring was continued for a further 2 hours. The organic layer was separated and dried.

Removal of the solvent in vacuo gave 2,6-dinitro-4-trifluoromethylaniline which melts after recrystallization from hexane-benzene at about 142-144 ° C.

2,6-dinitro-4-trifluoromethylaniline (g) is dissolved in 300 ml of ethanol. The solution is heated to approximately 35 ° C and 110 ml of a 20% ammonium polysulfide solution containing 5% free sulfur are added.

The temperature of the reaction mixture spontaneously rises to about 60 ° C and is heated at this temperature for about 10 minutes. The reaction mixture was then cooled to about 40 ° C and poured into water. The resulting mixture was filtered. Excess benzene was added to the filtrate and evaporated to dryness in vacuo using an azeotropic mixture of water and benzene. Recrystallization of the resulting solid gave purified 3-nitro-5-trifluoromethyl-o-phenylenediamine, melting at about 121-123 ° C.

The reaction mixture containing 3 g of 3-nitro-5-trifluoromethyl-o-phenylenediamine, 10 ml of trifluoroacetic acid and 25 ml of water was heated to reflux for about 4 hours.

The reaction product containing 2,6-bis- (trifluoromethyl) -4-nitro-benzimidazole was poured into water and stirred until it solidified. Benzimidazole is dissolved in basic medium at pH 11 and the solution is filtered. The pH is then lowered to approximately 7, with 2.6% of bls (trifluoromethyl) -4-nitrobenzimidazole starting to crystallize. The compound was collected by filtration, the filter cake was washed with water and then dried. Recrystallization from benzene / hexane gave 2,6-bis (trifluoromethyl) -4-nitrobenzimidazole, melting at about 95-97 ° C.

Analysis calculated: C 36.13%, N 14.05%, H 1.01%; Found: C 36.24, N 13.87, H 1.32.

Compounds in which the substituent at the 2-position of the benzimidazole ring is different from trifluoromethyl are prepared as described by Smith and Stiendle J. Am. Chem. Soc. 75, 1292 (1953), the process comprising heating an appropriately substituted orthophenylenediemine with trifluoroacetic acid, pentafluoropropionic acid, difluoroacetic acid, heptafluorobutyric acid, or chlorodifluoroacetic acid, preferably in the presence of a dilute hydrochloric acid solution.

The 2-chloro-difluoromethyl-4-nitro-6-trifluoromethylbenzimidazole thus prepared melts

at about 97-98 ° C after recrystallization from hexane. Analysis calculated: 34.25% C, 0.96% H, 13.31% N; found: 34.50% C, 1.01% H, 13.35% N.

Compounds in which the substituent at the 6 or 5 position of the benzene ring of the benzimidazole is difluoromethyl are prepared as described above from 2,6-dinitro-4-difluoromethylbenzene.

This compound is prepared by the reaction of SF4 and 3,5-dinitro-4-hydroxybenzaldehyde to give 2,6-dinitro-4-difluoromethylphenol, which is then converted to the corresponding chloride in a conventional manner. 2-Trifluoromethyl-4-nitro-6-difluoromethylbenzimidazole is prepared from the corresponding diamine by the above-described representative starting material and melts at about 132-134 ° C after recrystallization from benzene.

208666

Analysis calculated: 38.44% C, H, 1.43; N, 14.93; found: 38.30% C, H, 1.40; N, 14.82. Example 1 a d 1

2,6-bis- (trifluoromethyl) -4-nitro-1-phenylsulfonylbenzimidazole.

A solution containing 6.4 g of 2,6-bis- (trifluoromethyl) -4-nitrobenzimidazole anhydrous sodium salt is prepared in 50 ml of anhydrous acetonitrile. 3.5 g of benzenesulfonyl chloride and 20 ml of anhydrous acetonitrile are added.

The sodium chloride formed as a by-product of the reaction was separated by filtration and the 2,6-bis- (trifluoromethyl) -4-nitro-1-phenylsulfonylbenzimidazole thus prepared was isolated by evaporation of the solvent in vacuo.

Recrystallization of the product from benzene / pentane gave 2,6-bis- (trifluoromethyl) -4-nitro-1-phenylsulfonylbenzimidazole, m.p. 183-185 ° C. The nuclear magnetic resonance spectrum shows that the product of interest has been obtained and that no detectable impurities are present.

Example 2

2,6-Bis- (trifluoromethyl) -4-nitro-1-benzimidazolecarboxylic acid phenyl ester and 2,5-Bis- (trifluoromethyl) -7-nitro-1-benzimidazolecarboxylic acid phenyl ester.

The procedure was as in Example 1 except that phenyl chloroformate was used instead of benzenesulfonyl chloride. The product was isolated and recrystallized from pentane to give two fractions, the first melting at 83-92 ° C and the second at 92-95 ° C. The nuclear magnetic resonance spectrum shows that the compounds of interest were substantially free of impurities, although it was not possible to determine precisely what particular structure each of the two fractions had.

Other compounds prepared by the method of the preceding examples using the appropriate chloroformic acid ester or thiocarbamoyl chloride in place of the chloroformic acid phenyl ester include the following compounds:

2,6-bis (trifluoromethyl) -4-nitro-1-benzimidazolecarboxylic acid benzyl ester, m.p. 109-113 ° C, p-nitrophenyl ester 2, α-bis (trifluoromethyl) -4-nitro-1-benzimidazolecarboxylic acid, melting point 60-88 ° C, 2,5-bis (trifluoromethyl) -7-nitro-1-benzimidazolecarboxylic acid methyl ester, m.p. 93-98 ° C, 2,6-bis (trifluoromethyl) -4-nitro-1- methyl ester 93-98 ° C, 2,6-bis (trifluoromethyl) -4-nitro-1-benzimidazolecarboxylic acid n-hexyl ester, m.p. 40-43 ° C, 2,6-bis (trifluoromethyl) ethyl ester - 78-84 ° C, 2,6-bis (trifluoromethyl) -4-nitro-1-benzimidazolecarboxylic acid phenyl ester, m.p. 87-95 ° C, 2,6-bis isopropyl ester (trifluoromethyl) -4-nitro-1-benzimidazolecarboxylic acid, m.p. 49-55 ° C, 2,6-bis (trifluoromethyl) -4-nitro-1-benzimidazolecarboxylic acid allyl ester, m.p. 75 to 80 ° C,

N-ethyl-2,6-bis (trifluoromethyl) -4-nitro-benzimidazole-1-thiocarboxanilide, m.p. 96-104 ° C,

4-nitro-1-piperidinothlokarbonyl-2,6-bis (trifluoromethyl) benzimidazole, m.p. 112 DEG-126 DEG C.,

N, K-di-α-propyl-4-nitro-2,6-bis (trifluoromethyl) thio-1-benzimidazolecarboxamide, m.p. 118-127 ° C,

N, N-diethyl-4-nitro-2,6-bis (trifluoromethyl) thio-1-benzimidazolecarboxamide, m.p. 140-143 ° C,

N, N-dimethyl-4-nitro-2,6-bis (trifluoromethyl) thio-1-benzimidazolecarboxamide, m.p. 105-114 ° C.

Most of the compounds encompassed by formulas Ia and Ib are phytotoxic at doses substantially higher than those at which they are insecticidal, and many of them are effective herbicides against a number of plants at 8.8 kg / ha or above.

However, the highest efficacy of insecticides corresponding to formulas Ia and Ib provides sufficient marginal safety to be used either as soil additives in the presence of crop plants in growth or after sowing, or when applied as a single application to foliage as agricultural insecticidal products.

Example 3

Preparation of salts.

A mixture is prepared containing 6 g of 2,6-bis (trifluoromethyl) -4-nitrobenzimidazole, 1.1 g of sodium methylate and 100 ml of methanol. The reaction mixture was shaken and filtered. Evaporation of the filtrate to dryness gives a mixture of 2,6-bis (trifluoromethyl) nitrobenzimidazole sodium salt and 2,5-bis (trifluoromethyl) -7-nitrobenzimidazole sodium salt, m.p. 200 ° C. The mixture is water soluble, but insoluble in acid.

The compounds of the invention resemble organic phosphoric acid derivatives in terms of ingestion toxicity, but differ from organic phosphoric acid derivatives in that they have low toxicity when applied to the skin. The tables below contain estimates of acute oral and acute dermal toxicity of 2,6-bis (trifluoromethyl) -4-nitrobenzimidazole, in several mammalian species.

TabulkalO

Acute oral toxicity of 2,6-bis (trifluoromethyl) -4-nitrobenzimidazole.

Used animals

Estimated mg / kg mouse female rat male up to 20 to 22 female rat guinea pig male guinea pig female

Table 11

Acute dermal toxicity of 2,6-bis (trifluoromethyl) -4-nitrobenzimidazole.

Used animals Estimated LD 50, mg / kg rabbit male rabbit female > 500 > 500

The group of high-activity inaecticidal and acaricidal preparations within the formulas Ia and Ib consists of 2,6- (5) -bi8 (trifluoromethyl) -4- (7) -benzimidazole and its N ^1- derivatives, corresponding to the general formula

wherein R, R *, R, R 'and R have the meanings given above and n is an integer of 1 to 3. The use of compounds corresponding to the above formula as insecticidal and acaricidal substances is a preferred process of the invention.

Claims (8)

SUBJECT OF THE INVENTION An insecticidal and acaricidal hindered benzimidazole of the formula Ia and Ib, respectively, characterized in that, as active ingredient, a salt or a Ib, or a benzimidazole sodium salt of the general formula (Ia) optionally wherein R is a hydrogen atom, a group of ₂ (Ib) R * —_ U- ° -r o a group R ** -O-C- or И 0 where R * is hydrogen or nitro; and R is C 1 -C 6 alkyl or allyl, R * and R 'each represent a hydrogen atom, methyl, ethyl or phenyl, or together with the nitrogen atom to which they are attached form a piperidine ring and Y is a fluorine or hydrogen atom, Z is a fluorine, hydrogen or chlorine atom or a -CF ^ group or a CFg-CF ^ group, wherein the halogen atom mentioned above is an atom having an atomic number below 36; 2. A composition according to claim 1, wherein the fluoromethyl) -4-nitrobenzimidazole. 3. The composition of claim 1, wherein 2,6-bis- (trifluoromethyl) -4-nitrobenzimidazole. that it contains 2,6-bis (tri) as the active substance, and that it contains sodium as the active substance; 4. A composition according to claim 1 wherein the 2,6-bis- (trifluoromethyl) -4-nitro-1-benzimidazolecarboxylic acid ester. 5. A composition according to claim 1, wherein the active ingredient is fluoromethyl) -4-nitro-1-phenylsulfonylbenzimidazole. 6. A composition according to claim 1, wherein the active ingredient is 2,6-bis- (trifluoromethyl) -4-nitro-1-benzimidazolecarboxylic acid. 7. A composition according to claim 1, wherein the active ingredient is fluoromethyl-4-nitro-6-trifluoromethylbenzimidazole. 8. A composition according to claim 1, wherein the active ingredient is methyl-4-nitro-6-difluoromethylbenzimldazole. 2,6-bis (triallyl ester) 2-Chloro-2-trifluoro-