CN103524422A - Benzimidazole derivative, and preparation method and purpose thereof - Google Patents

Abstract

其中，R₁选自H、F、Cl、Br、CH₃、NO₃中的一种，-OR₂取代的位置为邻位、间位和对位中的一种。该苯并咪唑衍生物可以用于防治线虫，主要防治植物寄生线虫，如根结线虫，南方根结线虫（M.incognita）、爪哇根结线虫(M.javanica)、花生根结线虫(M.arenaria)和北方根结线虫(M.hapla)。也可以作为杀菌剂，防治多种病原菌。该苯并咪唑衍生物可以有效地控制植物害虫、害螨、线虫和病菌，可以应用在农业上防治病虫害，病原菌。The invention discloses a benzimidazole derivative as well as its preparation method and application. Its structural formula is as follows:

Wherein, R ₁ is selected from one of H, F, Cl, Br, CH ₃ , NO ₃ , and the substitution position of -OR ₂ is one of ortho, meta and para. The benzimidazole derivatives can be used to prevent and control nematodes, mainly plant parasitic nematodes, such as root-knot nematode, root-knot nematode incognita (M.incognita), root-knot nematode Java (M.javanica), root-knot nematode peanut (M. arenaria) and root-knot nematode (M.hapla). It can also be used as a fungicide to prevent and control a variety of pathogenic bacteria. The benzimidazole derivative can effectively control plant pests, harmful mites, nematodes and germs, and can be used in agriculture to prevent and control diseases and insect pests and pathogenic bacteria.

Description

Benzimidazole derivatives and their preparation and use

technical field

The invention relates to the technical field of insecticide and acaricide, in particular to benzimidazole derivatives and their preparation methods and applications.

Background technique

With the development of economy and society, people have higher and higher requirements for the economic benefits of agriculture, but the harm of agricultural pests and mites seriously affects the yield and quality of agricultural products. For example, aphids can harm a variety of plants, and the honeydew they secrete can Cause coal pollution; diamondback moth harms cabbage, cabbage and other cruciferous plants, affecting the quality of vegetables, so it is more and more important to kill pests and mites.

Contents of the invention

In view of this, the object of the present invention is to propose a kind of benzimidazole derivative and its preparation method and application, to effectively control plant pests, harmful mites, nematodes and germs.

Based on the above object, the structural formula of the benzimidazole derivative provided by the invention is as follows:

Wherein, R ₁ is selected from one of H, F, Cl, Br, CH ₃ , NO ₃ , the position substituted by -OR ₂ is one of ortho, meta and para, and R ₂ is selected from

和

中的一种。

and

One of.

Alternatively, the benzimidazole derivatives are prepared through the following steps:

Dissolving hydroxybenzaldehyde and sodium bisulfite in an aqueous ethanol solution, stirring at room temperature for 0.3-0.8 hours, and suction filtering the reaction mixture to obtain sodium hydroxybenzenemethanesulfonate;

Dissolve the sodium hydroxybenzenemethanesulfonate and substituted o-phenylenediamine in N,N-dimethylformamide, reflux for 1-3 hours, then pour the reaction mixture into ice, suction filter, and re- crystallized intermediates;

Dissolve the intermediate and triethylamine in dichloromethane, cool in an ice-salt bath to -3~-8°C, dissolve the acid chloride compound in dichloromethane to form an acid chloride solution, and then add the acid chloride solution to In the reaction system of the intermediate and triethylamine, the temperature is naturally raised to 24-28°C, and the stirring reaction is continued for 1-1.2h; the organic layer obtained by the reaction is separated, and then washed with water, dried, concentrated and separated by silica gel column chromatography The organic layer obtains the benzimidazole derivative;

Wherein, the structural formula of the substituted o-phenylenediamine is

The structural formula of the intermediate is

The structural formula of the acid chloride compound is R ₂ -Cl,

R ₁ is selected from one of H, F, Cl, Br, CH ₃ , NO ₃ ,

_R2 is selected from

和

中的一种。

and

One of.

The present invention also provides a method for preparing the above-mentioned benzimidazole derivatives, comprising the following steps:

Dissolving hydroxybenzaldehyde and sodium bisulfite in an aqueous ethanol solution, stirring at room temperature for 0.3-0.8 hours, and suction filtering the reaction mixture to obtain sodium hydroxybenzenemethanesulfonate;

Dissolve the sodium hydroxybenzenemethanesulfonate and substituted o-phenylenediamine in N,N-dimethylformamide, reflux for 1-3 hours, then pour the reaction mixture into ice, suction filter, and re- crystallized intermediates;

Dissolve the intermediate and triethylamine in dichloromethane, cool in an ice-salt bath to -3~-8°C, dissolve the acid chloride compound in dichloromethane to form an acid chloride solution, and then add the acid chloride solution to In the reaction system of the intermediate and triethylamine, the temperature is naturally raised to 24-28°C, and the stirring reaction is continued for 1-1.2h; the organic layer obtained by the reaction is separated, and then washed with water, dried, concentrated and separated by silica gel column chromatography The organic layer obtains the benzimidazole derivative;

Wherein, the structural formula of the substituted o-phenylenediamine is

The structural formula of the intermediate is

The structural formula of the acid chloride compound is R ₂ -Cl,

R ₁ is selected from one of H, F, Cl, Br, CH ₃ , NO ₃ ,

_R2 is selected from

和

中的一种。

and

One of.

Optionally, the hydroxybenzaldehyde is selected from one of 2-hydroxybenzaldehyde, 3-hydroxybenzaldehyde and 4-hydroxybenzaldehyde.

Optionally, the volume ratio of ethanol to water in the ethanol aqueous solution is 1:0.9-1.2.

Preferably, in the step of washing the organic layer with water, the organic layer is washed with water for 2 to 4 times, and the volume of water used for each washing is 1.3 to 1.8 times the volume of the organic layer.

Preferably, the washed organic layer is dried with anhydrous magnesium sulfate.

Optionally, the silica gel is 100-200 mesh, the eluent is petroleum ether and ethyl acetate, and the volume ratio of the petroleum ether and ethyl acetate is 4-1:1.

The present invention also provides the use of the above-mentioned benzimidazole derivatives, which are used for insecticide, acaricide and fungicide.

As can be seen from the above, the present invention provides a novel benzimidazole derivative, and the benzimidazole derivative provided by the invention can be used to control various agricultural, garden and storage harmful insects, such as Lepidoptera , Diptera, Homoptera and some invertebrate insects such as mites. Specifically: Aphisgossypii (Cotton aphid), Myzus persicae (Peach aphid), Lipaphis erysimi (Pipella aphid), Plutellaxylostella (Plutella xylostella), Nilaparvata lugens (Brown planthopper), Tetranychus cinnabarinus (Cinnabarinus), Pieris brassicae (Pipella cabbage butterfly), Anopheles spp .(Anopheles), Culex spp (Culex). It can also be used to control nematodes, mainly to control plant parasitic nematodes, such as root-knot nematode, southern root-knot nematode (M.incognita), Javan root-knot nematode (M.javanica), peanut root-knot nematode (M.arenaria) and northern root-knot nematode Knot nematode (M. hapla). It can also be used as a fungicide to prevent and control a variety of pathogenic bacteria. The benzimidazole derivative can effectively control plant pests, harmful mites, nematodes and germs, and can be used in agriculture to prevent and control diseases and insect pests and pathogenic bacteria.

Detailed ways

In order to make the object, technical solution and advantages of the present invention clearer, the present invention will be further described in detail below in conjunction with specific examples.

The structural formula of the benzimidazole derivative provided by the invention is as follows:

Wherein, R ₁ is selected from one of H, F, Cl, Br, CH ₃ , NO ₃ , the position substituted by -OR ₂ is one of ortho, meta and para, and R ₂ is selected from

和

中的一种。

and

One of.

The specific combinations of some compounds are shown in Table 1:

Table 1

The present invention also provides the preparation method of described benzimidazole derivatives, and its synthetic route is as follows:

Wherein, R ₁ is selected from one of H, F, Cl, Br, CH ₃ , NO ₃ , the position substituted by -OR ₂ is one of ortho, meta and para, and R ₂ is selected from

和中的一种。

and One of.

Among them, rt means room temperature, rf means reflux, and ice-salt baths.

Embodiment 1 (preparation method of compound 14)

Dissolve 0.04mol (4.88g) of p-hydroxybenzaldehyde and 0.04mol (4.16g) of sodium bisulfite in 40ml of aqueous ethanol (the volume ratio of ethanol and water is 1:1), and stir at room temperature for 0.5h. The mixture obtained by the reaction was filtered by suction to obtain 7.7 g of sodium p-hydroxybenzene methanesulfonate, and the yield was 86%.

Dissolve 0.01mol (2.26g) sodium p-hydroxybenzene methanesulfonate and 0.01mol (1.08g) o-phenylenediamine in 30ml of N,N-dimethylformamide, reflux for 2h; then pour the reaction mixture Pour into ice, filter with suction, and recrystallize to obtain 1.14g of 2-(2-hydroxybenzene)-1hydro-benzimidazole with a yield of 54%.

NMR data: ¹ HNMR, 300MHz, internal standard TMS, solvent CDCl ₃ , d: 7.93(d,2H), 7.57(br,1H), 7.55(m,2H), 7.21(m,2H), 6.93(d, 2H), 5.35 (br, 1H).

Dissolve 4mmol (0.84g) of 2-(2-hydroxybenzene)-1hydro-benzimidazole and 4mmol (0.42g) of triethylamine in 8ml of dichloromethane, and cool to -5°C in an ice-salt bath. Dissolve 4mmol (0.64g) of cyanoyl chloride in 8ml of dichloromethane to form a 0.05mol/l solution of cyanoyl chloride, and slowly add 2-(2-hydroxybenzene)-1hydro-benzimidazole and tris In the reaction system of ethylamine, the temperature was naturally raised to 26° C., and the stirring reaction was continued for 1 h. Separate the organic layer obtained by the reaction, wash the organic layer 3 times with 1.5 times the volume of water, then dry the washed organic layer with anhydrous magnesium sulfate, filter and concentrate the organic layer, and finally separate it with silica gel column chromatography (100- 200 mesh silica gel, the eluent is petroleum ether: ethyl acetate = 4:1-1:1), the product 1.1g was obtained, and the yield was 82%. The structural formula of the resulting product is:

NMR data: ¹ HNMR, 300MHz, internal standard TMS, solvent CDCl ₃ , d: 7.92(d,2H), 7.59(br,1H), 7.53(m,2H), 7.21(m,2H), 6.93(d, 2H), 1.07(d, 13H).

Embodiment 2 (preparation method of compound 15)

Dissolve 0.04mol (4.88g) of p-hydroxybenzaldehyde and 0.04mol (4.16g) of sodium bisulfite in 50ml of aqueous ethanol (the volume ratio of ethanol and water is 1:1.2), and stir at room temperature for 0.6h. The mixture obtained by the reaction was filtered by suction to obtain 7.7 g of sodium p-hydroxybenzene methanesulfonate, and the yield was 86%.

Dissolve 0.01mol (2.26g) of sodium p-hydroxybenzene methanesulfonate and 0.01mol (1.08g) of o-phenylenediamine in 35ml of N,N-dimethylformamide, and reflux for 1.5h; then the reaction mixture Pour into ice, filter with suction, and recrystallize to obtain 1.14g of 2-(2-hydroxybenzene)-1hydro-benzimidazole with a yield of 54%.

NMR data: ¹ HNMR, 300MHz, internal standard TMS, solvent CDCl ₃ , d: 7.93(d,2H), 7.57(br,1H), 7.55(m,2H), 7.21(m,2H), 6.93(d, 2H), 5.35 (br, 1H).

Dissolve 4mmol (0.84g) of 2-(2-hydroxybenzene)-1hydro-benzimidazole and 4mmol (0.42g) of triethylamine in 7ml of dichloromethane, and cool to -7°C in an ice-salt bath. 4mmol (0.92g) of 3-methyl-2-(4-chlorophenyl)butyryl chloride was dissolved in 8ml of dichloromethane to form 0.05mol/l of 3-methyl-2-(4-chlorophenyl)butyl The acid chloride solution was slowly added into the reaction system of 2-(2-hydroxybenzene)-1hydro-benzimidazole and triethylamine, the temperature was naturally raised to 28°C, and the stirring reaction was continued for 1.2h. Separate the organic layer obtained by the reaction, wash the organic layer 2 times with 1.8 times the volume of water, then dry the washed organic layer with anhydrous magnesium sulfate, filter and concentrate the organic layer, and finally separate it with silica gel column chromatography (100- 200 mesh silica gel, the eluent is petroleum ether:ethyl acetate=4:1-1:1), the product 1.2g was obtained, and the yield was 74%. The structural formula of the resulting product is:

NMR data: 1HNMR, 300MHz, internal standard TMS, solvent CDCl3, d: 7.96(d,2H), 7.57(br,2H), 7.35(m,4H), 7.24(m,3H), 7.05(d,2H) , 3.37(s,1H), 2.44(m,1H), 1.17(t,3H), 0.75(m,3H).

Embodiment 3 (preparation method of compound 30)

Dissolve 0.04mol (4.88g) of p-hydroxybenzaldehyde and 0.04mol (4.16g) of sodium bisulfite in 45ml of aqueous ethanol (the volume ratio of ethanol and water is 1:0.9), and stir at room temperature for 0.3h. The mixture obtained by the reaction was filtered by suction to obtain 7.7 g of sodium p-hydroxybenzene methanesulfonate, and the yield was 86%.

Dissolve 0.01mol (2.26g) of sodium p-hydroxybenzenemethanesulfonate and 0.01mol (1.26g) of 4-fluoro-o-phenylenediamine in 30ml of N,N-dimethylformamide and reflux for 3h; then the reaction was obtained The mixture was poured into ice, suction filtered, and recrystallized to obtain 1.14g of 2-(2-hydroxybenzene)-1hydro-(4-fluoro)benzimidazole with a yield of 50%.

NMR data: ¹ HNMR, 300MHz, internal standard TMS, solvent CDCl ₃ , d: 7.93(d,2H), 7.57(br,1H), 7.55(m,2H), 7.21(m,2H), 6.939(d, 2H), 5.35 (br, 1H).

Dissolve 4mmol (0.91g) of 2-(2-hydroxybenzene)-1hydro-(4-fluoro)benzimidazole and 4mmol (0.42g) of triethylamine in 10ml of dichloromethane, and cool in an ice-salt bath to - 8°C. Dissolve 4mmol (0.92g) of 3-methyl-2-(4-chlorophenyl)butyryl chloride in 8ml of dichloromethane to prepare 0.05mol/l of 3-methyl-2-(4-chlorophenyl) Butyryl chloride solution was slowly added into the reaction system of 2-(2-hydroxybenzene)-1hydro-(4-fluoro)benzimidazole and triethylamine, the temperature was naturally raised to 28°C, and the reaction was continued for 1.1h with stirring. Separate the organic layer obtained by the reaction, wash the organic layer 4 times with 1.3 times the volume of water, then dry the washed organic layer with anhydrous magnesium sulfate, filter and concentrate the organic layer, and finally separate it with silica gel column chromatography (100- 200 mesh silica gel, the eluent is petroleum ether:ethyl acetate=4:1-1:1), the product 1.2g was obtained, and the yield was 74%. The structural formula of the resulting product is:

NMR data: ¹ HNMR, 300MHz, internal standard TMS, solvent CDCl ₃ , d: 7.98(d,2H), 7.57(br,2H), 7.35(m,4H), 7.24(m,3H), 7.05(d, 2H), 3.37(s, 1H), 2.44(m, 1H), 1.17(t, 3H), 0.75(m, 3H).

Embodiment 4 (preparation method of compound 74)

Dissolve 0.04mol (4.88g) of p-hydroxybenzaldehyde and 0.04mol (4.16g) of sodium bisulfite in 38ml of aqueous ethanol (the volume ratio of ethanol and water is 1:1.1), and stir at room temperature for 0.8h. The mixture obtained by the reaction was filtered by suction to obtain 7.7 g of sodium p-hydroxybenzene methanesulfonate, and the yield was 86%.

Dissolve 0.01mol (2.26g) of sodium p-hydroxybenzenemethanesulfonate and 0.01mol (1.22g) of 4-methyl-o-phenylenediamine in 30ml of N,N-dimethylformamide, and reflux for 1h; then the reaction The resulting mixture was poured into ice, filtered with suction, and recrystallized to obtain 1.1 g of 2-(2-hydroxybenzene)-1hydro-(4-methyl)benzimidazole with a yield of 51%.

NMR data1 HNMR, 300MHz, internal standard TMS, solvent CDCl ₃ , d: 7.93( ^d ,2H), 7.57(br,1H), 7.55(m,2H), 7.21(m,2H), 6.93(d,2H ), 5.35 (br, 1H), 2.34 (s, 3H).

Dissolve 4 mmol (0.89 g) of 2-(2-hydroxybenzene)-1 hydrogen-(4-methyl) benzimidazole and 4 mmol (0.42 g) of triethylamine in 10 ml of dichloromethane, and cool in an ice-salt bath to -3°C. Dissolve 4mmol (0.64g) of fenchromoyl chloride in 8ml of dichloromethane to form a 0.05mol/l methanoyl chloride solution, and slowly add it to 2-(2-hydroxybenzene)-1hydrogen-(4-methyl ) in the reaction system of benzimidazole and triethylamine, the temperature was naturally raised to 24° C., and the stirring reaction was continued for 1.1 h. Separate the organic layer obtained by the reaction, wash the organic layer 3 times with 1.5 times the volume of water, then dry the washed organic layer with anhydrous magnesium sulfate, filter and concentrate the organic layer, and finally separate it with silica gel column chromatography (100- 200 mesh silica gel, the eluent is petroleum ether:ethyl acetate=4:1-1:1), the product 1.1g was obtained, and the yield was 71%. The structural formula of the resulting product is:

NMR data: ¹ HNMR, 300MHz, internal standard TMS, solvent CDCl ₃ , d: 7.92(d,2H), 7.59(br,1H), 7.53(m,2H), 7.21(m,2H), 6.93(d, 2H), 2.34(s, 3H), 1.07(d, 13H).

The benzimidazole derivatives provided by the invention can be used to control various agricultural, garden and storage harmful insects, such as Lepidoptera, Diptera, Homoptera and some invertebrate insects, such as mites. Specifically: Aphis gossypii (Cotton aphid), Myzus persicae (Peach aphid), Lipaphis erysimi (Pipella aphid), Plutella xylostella (Plutella xylostella), Nilaparvata lugens (Brown planthopper), Tetranychuscinnabarinus (Cinnabar spider mite), Pieris brassicae (Pipella cabbage butterfly), Anopheles spp. (Anopheles), Culex spp (Culex).

The benzimidazole derivatives provided by the present invention can be used for preventing and controlling nematodes, mainly controlling plant parasitic nematodes, such as root-knot nematode, root-knot nematode incognita (M.incognita), root-knot nematode Java (M.javanica), root-knot nematode peanut (M. arenaria) and root-knot nematode (M. hapla).

The benzimidazole derivatives provided by the invention can also be used as fungicides to prevent and treat various pathogenic bacteria.

The benzimidazole derivatives provided by the present invention are made into various forms of compositions, such as powders, wettable powders, granules, emulsifiable concentrates, suspension concentrates, etc., and applied to soil, plants, and seeds. In order to effectively control harmful insects, harmful mites, nematodes, etc., when the benzimidazole derivative is made into a corresponding composition, the composition contains 15%-90% of the benzimidazole derivative by mass fraction.

The benzimidazole derivatives provided by the invention are used to measure the biological activity of several insects and acarids. The assay method is: after the benzimidazole derivatives are dissolved in dimethyl sulfoxide, an aqueous solution containing 0.1% Tween 100 is used Dilute the benzimidazole derivative solution to the desired concentration.

Targeting Myxus persicae (Peach aphid), Plutella xylostella (Plutella xylostella), Nilaparvatalugens (BPH), and Tetranychus cinnabarinus (Tetranychus cinnabarinus), the airbrush spray method and immersion method were used to identify the insecticidal activity. The spray pressure of the airbrush spray method was 10psi (approximately 0.7kg/cm ² ), the spray volume is 0.5ml, and the mortality of the target is investigated 48-72 hours after treatment.

The specific operation process is as follows:

(1) Control of aphids (spray method): Dissolve 20mg of benzimidazole derivatives in 2ml of dimethyl sulfoxide to form a 10mg/ml stock solution, and then dilute the stock solution to a certain concentration with an aqueous solution containing 0.1% Tween 100 . Use a hand-held sprayer to apply the test solution onto leaves containing the appropriate aphids (approximately 30-50 aphids/leaf) until the test solution runs off the sides of the leaves. Each compound was replicated 3 times at each concentration. The blank control was only treated with an aqueous solution containing 0.1% Tween 100. Keep the leaves for 2-3 days under the conditions of 23°C and 40% relative humidity, record the total number and dead number of aphids on each leaf, and calculate the mortality rate.

(2) Control of Plutella xylostella (immersion method): Dissolve 20mg of benzimidazole derivatives in 2ml of dimethyl sulfoxide to form a 10mg/ml stock solution, and then dilute the stock solution with an aqueous solution containing 0.1% Tween 100 to A certain concentration. Cut the leaves of cabbage into discs with a diameter of about 7cm, soak them in a test solution of a certain concentration for 5-10s, take them out and dry them in the air, place 10-20 diamondback moths on each leaf, seal with plastic wrap, and repeat for each concentration of medicine 3 times. The temperature is 24°C, the humidity is 70%, and the breeding is carried out for 24-48 hours. The total number of insects and the number of dead insects in each petri dish are recorded.

(3) Control of brown planthopper (spray method and system test): immerse the seedlings in the water at the bottom of the two-part glass cylinder, use a metal mesh screen to support the seedlings at the bottom, and then use scotch tape to connect the two parts of the glass cylinder. Each treatment uses three cylinders. Dissolve 20 mg of benzimidazole derivatives in 2 ml of dimethyl sulfoxide to prepare a 10 mg/ml stock solution, and dilute the stock solution to different concentrations with an aqueous solution containing 0.1% Tween 100. 0.5 ml of the test solution and the solvent control and the blank control were sprayed into the glass cylinder. For the system test, the stock solution was added to the water of the test seedlings to form different concentrations. In the foliar spray and system tests, 3rd instar nymphs of N. lugens were introduced into cylinders 3 h after application. The treated test unit (cylinder) was placed in a growth chamber with a temperature of 28°C and a humidity of 70%, and observations and records were made on day 2 and day 6.

(4) Control of Tetranychus cinnabarinus (drug film method): dilute the benzimidazole derivatives with acetone into different concentrations of liquid medicine, repeat each concentration 3 times, draw 1.2ml from the diluted liquid medicine and add 1.5 ml centrifuge tube, gently rotate the centrifuge tube to form a uniform drug film on the inner wall of the tube, pour off the excess drug solution, and put it in a ventilated place until the acetone is completely volatilized. The control is treated with acetone alone, and the method is the same. Place 30 healthy and consistent adult mites in each drug-coated tube, and check the mortality rate for 24 hours under normal indoor feeding conditions. Death standard: lightly touch the insect body with a brush, if only one foot moves or does not move at all, it is dead. A control mortality rate of less than 10% was considered valid.

(5) Control of Anopheles larvae: Dilute the benzimidazole derivatives with dechlorinated tap water containing 0.1% Tween into different concentrations of liquid medicine, domesticate the Anopheles larvae in the dechlorinated tap water, and pick the size respectively Forty 3rd-instar larvae with consistent and rapid activities were placed in different concentrations of the drug solution, and each concentration was repeated three times. The tap water without drug application was used as the blank control, and the mortality rate of the larvae after 2 hours of treatment was calculated.

The test results are as follows:

Table 2

It should be noted that the benzimidazole derivative provided by the present invention can be used in the form of a composition for killing insects and acarids, and the composition comprises a benzimidazole derivative and a phytologically acceptable carrier. The composition can be applied in various forms such as spray, topical treatment, seed coating, microcapsule, systemic absorption, bait, etc., to achieve the purpose of controlling insects. The composition may be a concentrated solid or liquid formulation (dissolved in water for use) or a granular formulation. Most of the dispersions of benzimidazole derivatives are aqueous suspensions or emulsions made from concentrated formulations of benzimidazole derivatives. These water-soluble, water-suspendable and emulsifiable formulations are commonly referred to as wettable powders or wettable granules. They are a uniform mixture of active compounds (ie benzimidazole derivatives), inert carriers and surfactants, and the concentration of active compounds is usually 10%-90% of the mass fraction. The carrier is usually montmorillonite clay, diatomaceous earth, silicate and attapulgite clay, accounting for 0.5%-10% of the wettable powder (granule). The surfactant can be naphthalene sulfonate, alkylnaphthalene sulfonate, alkyl sulfate and non-ionic surfactant.

The benzimidazole derivatives can also be dissolved in a suitable organic solvent and re-dispersed in the form of a solution for use. Insecticides and acaricides are usually used with active ingredients in a liquid carrier, and the usage rate is determined according to the concentration of the active ingredients. The carrier is usually water. Usually the concentration of the active ingredient is 10mg/kg-5000mg/kg, which can be well controlled, and 10mg/kg-500mg/kg is sufficient for most compounds. The site of application of the compound may be any site where insects or mites gather, such as vegetable crops, fruit, ornamental plants, surfaces of buildings, soil, and the like. The compounds of the invention can be applied together with one or more insecticides, fungicides and herbicides, or sequentially.

It can be seen that the benzimidazole derivatives provided by the present invention can effectively control plant pests, harmful mites, nematodes and pathogens, and can be applied in agriculture to prevent and control pests and pathogenic bacteria.

Those of ordinary skill in the art should understand that: the above descriptions are only specific embodiments of the present invention, and are not intended to limit the present invention. Any modifications, equivalent replacements, and improvements made within the spirit and principles of the present invention etc., should be included within the protection scope of the present invention.

Claims (9)

1. a benzimidazole derivative, characterized in that its structural formula is as follows:

Wherein, R ₁ is selected from one of H, F, Cl, Br, CH ₃ , NO ₃ , the position substituted by -OR ₂ is one of ortho, meta and para, and R ₂ is selected from

and

One of. 2. benzimidazole derivative according to claim 1, is characterized in that, described benzimidazole derivative is made through the following steps: Dissolving hydroxybenzaldehyde and sodium bisulfite in an aqueous ethanol solution, stirring at room temperature for 0.3-0.8 hours, and suction filtering the reaction mixture to obtain sodium hydroxybenzenemethanesulfonate; Dissolve the sodium hydroxybenzenemethanesulfonate and substituted o-phenylenediamine in N,N-dimethylformamide, reflux for 1-3 hours, then pour the reaction mixture into ice, suction filter, and re- crystallized intermediates; Dissolve the intermediate and triethylamine in dichloromethane, cool in an ice-salt bath to -3~-8°C, dissolve the acid chloride compound in dichloromethane to form an acid chloride solution, and then add the acid chloride solution to In the reaction system of the intermediate and triethylamine, the temperature is naturally raised to 24-28°C, and the stirring reaction is continued for 1-1.2h; the organic layer obtained by the reaction is separated, and then washed with water, dried, concentrated and separated by silica gel column chromatography The organic layer obtains the benzimidazole derivative; Wherein, the structural formula of the substituted o-phenylenediamine is

The structural formula of the intermediate is

The structural formula of the acid chloride compound is R ₂ -Cl, R ₁ is selected from one of H, F, Cl, Br, CH ₃ , NO ₃ , _R2 is selected from

and

One of. 3. a method for preparing the described benzimidazole derivatives of claim 1, is characterized in that, comprises the following steps: Dissolving hydroxybenzaldehyde and sodium bisulfite in an aqueous ethanol solution, stirring at room temperature for 0.3-0.8 hours, and suction filtering the reaction mixture to obtain sodium hydroxybenzenemethanesulfonate; Dissolve the sodium hydroxybenzenemethanesulfonate and substituted o-phenylenediamine in N,N-dimethylformamide, reflux for 1-3 hours, then pour the reaction mixture into ice, suction filter, and re- crystallized intermediates; Dissolve the intermediate and triethylamine in dichloromethane, cool in an ice-salt bath to -3~-8°C, dissolve the acid chloride compound in dichloromethane to form an acid chloride solution, and then add the acid chloride solution to In the reaction system of the intermediate and triethylamine, the temperature is naturally raised to 24-28°C, and the stirring reaction is continued for 1-1.2h; the organic layer obtained by the reaction is separated, and then washed with water, dried, concentrated and separated by silica gel column chromatography The organic layer obtains the benzimidazole derivative; Wherein, the structural formula of the substituted o-phenylenediamine is

The structural formula of the intermediate is

The structural formula of the acid chloride compound is R ₂ -Cl, R ₁ is selected from one of H, F, Cl, Br, CH ₃ , NO ₃ , _R2 is selected from

and One of. 4. the preparation method of benzimidazole derivative according to claim 3 is characterized in that, described hydroxybenzaldehyde is selected from 2-hydroxybenzaldehyde, the one in 3-hydroxybenzaldehyde and 4-hydroxybenzaldehyde . 5. The method for preparing benzimidazole derivatives according to claim 3, characterized in that the volume ratio of ethanol to water in the ethanol aqueous solution is 1:0.9-1.2. 6. the preparation method of benzimidazole derivative according to claim 3 is characterized in that, in the step of described washing organic layer, adopts water to wash organic layer 2～4 times, the volume of water used for each washing is 1.3 to 1.8 times the volume of the organic layer. 7. The preparation method of benzimidazole derivatives according to claim 6, characterized in that, anhydrous magnesium sulfate is used to dry the washed organic layer. 8. the preparation method of benzimidazole derivative according to claim 3 is characterized in that, described silica gel is 100～200 order, eluent is sherwood oil and ethyl acetate, and described sherwood oil and ethyl acetate The volume ratio of esters is 4-1:1. 9. The use of benzimidazole derivatives according to claim 1, characterized in that the benzimidazole derivatives are used for insecticide, acaricide and bactericide.