阅读说明：本技术 一类1,2,4-三唑席夫碱硫醚衍生物及其制备方法和用途 (1,2, 4-triazole Schiff base thioether derivatives, and preparation method and application thereof ) 是由 王彦恩 张金林 陈来 于 2020-05-27 设计创作，主要内容包括：本发明提供了一类1,2,4-三唑席夫碱硫醚衍生物及其制备方法和用途,本发明涉及1,2,4-三唑席夫碱硫醚类衍生物,它们具有如5所示的化学结构通式：其中,R～(1)选自：2-吡啶基、3-噻吩基；R～(2)选自：2,4-二氯苯基、2-吡啶基、3,5-二甲基异恶唑基、1,2,4-三唑啉-5-酮基、环丙基；R～(3)选自：5-氯-2-氟苯基、4-硝基苯基、5-甲基呋喃基、2-噻吩基；本发明公开了上述化合物的结构通式、合成方法与用作除草剂的用途,其与农业上可接受的助剂或增效剂以及与商品除草剂组合使用在防治农业、林业、园艺杂草中的用途和制备方法。(The invention provides 1,2, 4-triazole Schiff base thioether derivatives, a preparation method and application thereof, and relates to 1,2,4-Triazole Schiff base thioether derivatives have a chemical structural general formula shown as 5: wherein R is 1 Selected from: 2-pyridyl, 3-thienyl; r 2 Selected from: 2, 4-dichlorophenyl, 2-pyridyl, 3, 5-dimethylisoxazolyl, 1,2, 4-triazolin-5-onyl, cyclopropyl; r 3 Selected from: 5-chloro-2-fluorophenyl, 4-nitrophenyl, 5-methylfuryl, 2-thienyl; the invention discloses a structural general formula of the compound, a synthesis method and application of the compound as a herbicide, and application and a preparation method of the compound in preventing and treating agricultural, forestry and gardening weeds by combining the compound with agriculturally acceptable auxiliary agents or synergists and commercial herbicides.)

1. A1, 2, 4-triazole Schiff base thioether derivative is characterized by having a chemical structural general formula shown as a formula 5:

5:

wherein R is¹Selected from: 2-pyridyl, 3-thienyl; r²Selected from: 2, 4-dichlorophenyl, 2-pyridyl, 3, 5-dimethylisoxazolyl, 1,2, 4-triazolin-5-onyl, cyclopropyl; r³Selected from: 5-chloro-2-fluorophenyl, 4-nitrophenyl, 5-methylfuryl and 2-thienyl.

2. The 1,2, 4-triazole schiff base thioether derivative 5 of claim 1, which is synthesized by the following method:

wherein R is¹Selected from: 2-pyridyl, 3-thienyl; r²Selected from: 2, 4-dichlorophenyl, 2-pyridyl, 3, 5-dimethylisoxazolyl, 1,2, 4-triazolin-5-onyl, cyclopropyl; r³Selected from: 5-chloro-2-fluorophenyl, 4-nitrophenyl, 5-methylfuryl, 2-thienyl;

the specific method for synthesizing the 1,2, 4-triazole Schiff base thioether derivative and measuring the biological activity comprises the following steps of:

A. the preparation method of the compound 2 comprises the following steps:

in a 50mL single-neck round-bottom flask, 0.60mL of 80% hydrazine hydrate solution and 0.0041mol of methyl aryl (hetero) cycloformate 1 are sequentially added, wherein the methyl aryl (hetero) cycloformate is selected from the following components: heating a system to reflux by using 2-picolinic acid methyl ester and thiophene-3-formic acid methyl ester, monitoring the reaction process by using TCL (thermal transfer chromatography), stopping the reaction after reacting for about 5 hours, cooling the system to room temperature, adding a small amount of absolute ethyl alcohol into a reaction solution, carrying out reduced pressure rotary evaporation to remove redundant hydrazine hydrate, recrystallizing the residual solid in the ethyl alcohol to obtain a white solid, and drying in a vacuum drying oven to obtain the aromatic heterocyclic hydrazide 2 with the yield of 85-90%; the amount of compound 2 produced and the volume of the reaction vessel are scaled up or down accordingly.

B. A method for preparing compound 3:

0.0041mol of aro (hetero) cyclohydrazide 2 was added to an absolute ethanol solution of KOH (0.46g, 0.0082mol), and CS (0.74mL, 0.0123mol) was added dropwise to the solution under ice-bath conditions₂Heating the solution to reflux, monitoring the reaction process by TCL (thermal transfer chromatography), after the reaction is finished, carrying out reduced pressure rotary evaporation on the solvent to obtain a crude product, namely potassium salt of aryl (hetero) ring-3-oxadiazole sulfydryl, continuously carrying out reflux reaction on the potassium salt in 3mL of 80% hydrazine hydrate solution for about 4 hours, then pouring the reaction solution into 200mL of ice water for dissolving, adjusting the pH value of the solution to be about 5 by using 10% HCl, generating yellow precipitate, carrying out reduced pressure suction filtration, and carrying out overnight drying in a vacuum drying oven to obtain 4-amino-5-sulfydryl-1, 2, 4-triazole compound 3, wherein the yield is 70-82%; the amount of compound 3 produced and the volume of the reaction vessel are scaled up or down accordingly.

C. A method for preparing compound 4:

in a dry 50mL round bottom flask, 0.0025mol of compound 3, 5mL of anhydrous ethanol solvent, 1.05mL of triethylamine, 0.0030mol of bromomethyl aryl (hetero) cyclic derivative selected from: heating a system to reflux by 1-bromomethyl-2, 4-dichlorobenzene, 2-bromomethylpyridine, 4-bromomethyl-3, 5-dimethylisoxazole, 3-chloromethyl-1, 2, 4-triazoline-5-one and bromomethyl cyclopropane, monitoring the reaction process by TLC, decompressing and distilling a solvent after the reaction is finished, dissolving a crude product by using 80mL of dichloromethane, washing by using 50mL of saturated saline solution, carrying out extraction separation, drying an organic layer by using anhydrous sodium sulfate, carrying out suction filtration and decompression and rotary distillation on the solvent, carrying out silica gel column chromatography purification on the crude product by using 200-300 meshes to obtain an eluent of dichloromethane and ethyl acetate, wherein the volume ratio is 10:1-50:1 and the yield is 85-97% according to different products, and obtaining the 1,2, 4-triazolylamino derivative 4.

D. A method for preparing compound 5:

0.7 mmole of 1,2, 4-triazolylamino derivative 4 was dissolved in 4mL of glacial acetic acid solvent, 0.7 mmole of an aromatic (hetero) cyclic formaldehyde was added, said aromatic (hetero) cyclic formaldehyde being selected from: heating a system to reflux by using 5-chloro-2-fluorobenzaldehyde, 4-nitrobenzaldehyde, 5-methylfuran-2-aldehyde and 2-thiophenecarboxaldehyde, monitoring the reaction process by using TCL (thermal transfer chromatography), decompressing and distilling to remove a solvent after the reaction is finished, purifying a crude product by using 200-300-mesh silica gel column chromatography, and separating and purifying to obtain the 1,2, 4-triazole Schiff base thioether compound 5. The eluent is dichloromethane and methanol, the volume ratio is 50: 1-100: 1 according to different products, the yield is 70-95%, and the preparation amount of the compound 5 and the volume of a reaction container are enlarged or reduced according to corresponding proportion.

3. Use of the 1,2, 4-triazole schiff base thioether derivative 5 of claim 1 with an agriculturally acceptable adjuvant for the preparation of herbicides.

4. The 1,2, 4-triazole schiff base thioether derivative 5 of claim 1, in combination with any one or more of the commercial herbicides nicosulfuron, tribenuron-methyl, cinosulfuron, sulfometuron-methyl, penoxsulam, alachlor, acetochlor, butachlor, metolachlor, 2-methyl-4-chloro, trifluralin, mesotrione, topramezone, pendimethalin, atrazine, prometryn, cyanazine, ametryn, metribuzin, aclonifen, oxyfluorfen, acifluorfen, lactofen, fluoroglycofen-ethyl, pyraflufen-ethyl, iprobenfos, imazapyr, imazamox, imazaquin, imazapyr, pyriminobac, and pyriminobac, Pyriftalid, phenmedipham, desmedipham, dichlorvos, pyributicarb, dicamba, folpet, haloxyfop, benazolin, quizalofop, thia diclofop, fluroxypyr, dithiopyr, fluazinone, thiazopyr, diflufenzopyr, paraquat, glyphosate, anil, fluroxypyr, flumioxazin, fluthiacet, flufenacet, fluthiacet, metribuzin, pyraflutole, pyraflufen-ethyl, isoxaflutole, bromoxynil, and the like; the total mass percentage content of the 1,2, 4-triazole Schiff base thioether derivative 5 in the compound herbicide is 1% -90%, and the mass percentage of the 1,2, 4-triazole Schiff base thioether derivative 5 to the commercial herbicide is 1% -99% -1%; the formulation suitable for the compound herbicide is any one of wettable powder, microcapsule suspending agent, dispersible liquid formulation, dispersible solid formulation, seed treatment emulsion, aqueous emulsion, large granule, microemulsion, oil suspending agent, water soluble granule, soluble concentrate, water dispersible granule, poison grain, aerosol, sustained release block, capsule granule, dry-mixed seed powder, missible oil, electrostatic spray, aqueous oil-in-oil emulsion, oil-in-water emulsion, aerosol can, fine granule, aerosol candle, aerosol cylinder, aerosol stick, seed treatment suspending agent, aerosol tablet, aerosol pill, gas generating agent, drift powder, ointment, hot fogging concentrate, solid/liquid mixed package agent, liquid/liquid mixed package agent, cold fogging concentrate, solid/solid mixed package agent, medicinal paint, seed treatment liquid, microgranule, oil dispersible powder, colloid, pour-on agent, smearing agent, Suspending emulsion, film-forming oil agent, soluble powder, seed treatment water-soluble powder, ultra-low volume suspending agent, tracing powder, ultra-low volume liquid, steam releasing agent, and wet-mixed seed water-dispersible powder; the plant suitable for the compound herbicide is selected from rice, wheat, barley, oat, corn, sorghum, sweet potato, cassava, soybean, sweet broad bean, pea, mung bean, small bean, cotton, silkworm, peanut, rape, sesame, sunflower, beet, sugarcane, coffee, cocoa, ginseng, fritillaria, rubber, coconut, oil palm, sisal, tobacco, tomato, pepper, radish, cucumber, cabbage, celery, tuber mustard, beet, rape, shallot, garlic, watermelon, melon, cantaloupe, papaya, apple, orange, peach, tea, potherb, bamboo shoot, hop, pepper, banana, papaya, orchid, bonsai; the compound herbicide is suitable for controlling weeds and is selected from: grassy weeds: crab grass, green bristlegrass herb, goosegrass herb, barnyard grass, moleplant seed, tiger tail grass, wild oat, teff grass, golden green bristlegrass herb, long silvergrass club grass, amur foxtail and the like; broad-leaved weeds such as Amaranthus retroflexus, herba Portulacae, fructus Chenopodii, herba Desmodii Trifoliatae, herba Acalyphae, herba Xanthii, Ambrosia, piemarker, Kochiae fructus, herba Solani Nigri, herba Spinaciae, herba Stellariae, herba Moslae, herba Ecliptae, herba seu radix Valerianae, herba Convolvuli Alsinoides, and semen Cuscutae; cyperaceae weeds such as herba Tagetis Erectae, herba Cyperi Erectae, herba Salsolae Collinae, herba Alii Fistulosi, etc.

Technical Field

The technical scheme of the invention relates to a 1,2, 4-triazole Schiff base thioether compound, in particular to a thioether derivative containing 1,2, 4-triazole Schiff base.

Background

The use of the herbicide can improve the yield and the quality of grains and plays an important role in crop production. However, in recent years, the herbicide resistance of weeds is rapidly developed due to the long-term use of a large amount of the same herbicide or the same action mechanism (Perotti V.E., Plant Sci.,2020,290:110255-110270.), the herbicide resistance directly causes the reduction of the pesticide effect and the increase of the use amount of the herbicide, and vicious circle is caused, so that the effective solution of the weed resistance is a problem to be solved for creating new pesticides.

At present, the biological reasonable design of new pesticide molecules is mainly based on the existing known target enzymes, so as to obtain new compounds with biological activity, but the pesticide with a single target is used in a large amount for a long time, so that the drug resistance risk of pests is inevitably increased, and if the pesticides with the same or similar targets are alternately used, the Pest resistance problem becomes more serious (Thomas C.S., Pest Manag.Sci.,2017,73: 672-. The newly discovered targets can provide a basis for developing pesticide molecules with new action mechanisms, so that the weed resistance risk is effectively solved (Wang T., Curr.Pharm.Biotechno.,2015,16(1):11-25.), and therefore, the development of herbicides with the new action targets is one of effective methods for controlling resistant weeds.

Transketolase is an important enzyme in the carbon metabolism and Karlvin cycle of plants (Yamaoka C., Plant Cell physiol.,2016,57(1):115-124.), and plays an important role in the photosynthesis of plants. The subject group utilizes the related technology to confirm that the transketolase is a new herbicide action target (Zhao B., Toxins,2018,10(1):1-14.), and the crystal structure of the transketolase has been reported at present (Nikkola M., J.mol.biol.,1994,238(3): 387-404) so that the research and development of the completely new action mechanism herbicide by taking the enzyme as the target are of great significance.

Recently, a subject group virtually screens a ZIBC database based on target transketolase to obtain a pyrazole amide lead compound ZINC12007063(Huo J.Q., macromolecules, 2018,23: 2116). the invention uses a 4-amino-5-mercaptotriazole active substructure as a mother nucleus, adopts a framework transition strategy, carries out lead optimization on the ZINC12007063, designs and synthesizes series 1,2, 4-triazole Schiff base thioether compounds, and carries out systematic weeding bioactivity screening so as to provide more efficient candidate compounds for the creation of novel herbicides.

Disclosure of Invention

The technical problem to be solved by the invention is as follows: provides a synthesis method of a novel 1,2, 4-triazole Schiff base thioether derivative, a method for regulating and controlling the biological activity of agricultural, horticultural and forestry weeds and a determination method thereof, and also provides application of the compounds in the agricultural field, the horticultural field and the forestry field.

The technical scheme adopted by the invention for solving the technical problem is as follows: the chemical structural general formula of the 1,2, 4-triazole Schiff base thioether compound with herbicidal activity in the agricultural field, the horticultural field and the forestry field is shown as formula 5:

5:

wherein R is¹Selected from: 2-pyridyl, 3-thienyl; r²Selected from: 2, 4-dichlorophenyl, 2-pyridyl, 3, 5-dimethylisoxazolyl, 1,2, 4-triazolin-5-onyl, cyclopropyl; r³Selected from: 5-chloro-2-fluorophenyl, 4-nitrophenyl, 5-methylfuryl, 2-thienyl;

the synthesis method of the 1,2, 4-triazole Schiff base thioether derivative 5 comprises the following steps:

wherein R is¹Selected from: 2-pyridyl, 3-thienyl; r²Selected from: 2, 4-dichlorophenyl, 2-pyridyl, 3, 5-dimethylisoxazolyl, 1,2, 4-triazolin-5-onyl, cyclopropyl; r³Selected from: 5-chloro-2-fluorophenyl4-nitrophenyl, 5-methylfuryl, 2-thienyl;

the specific method for synthesizing the 1,2, 4-triazole Schiff base thioether derivative 5 and measuring the biological activity comprises the following steps of:

A. the preparation method of the compound 2 comprises the following steps:

in a 50mL single-neck round-bottom flask, 0.60mL of 80% hydrazine hydrate solution and 0.0041mol of methyl aryl (hetero) cycloformate 1 are sequentially added, wherein the methyl aryl (hetero) cycloformate is selected from the following components: heating a system to reflux by using 2-picolinic acid methyl ester and thiophene-3-formic acid methyl ester, monitoring the reaction process by using TCL (thermal transfer chromatography), stopping the reaction after reacting for about 5 hours, cooling the system to room temperature, adding a small amount of absolute ethyl alcohol into a reaction solution, carrying out reduced pressure rotary evaporation to remove redundant hydrazine hydrate, recrystallizing the residual solid in the ethyl alcohol to obtain a white solid, and drying in a vacuum drying oven to obtain the aromatic heterocyclic hydrazide 2 with the yield of 85-90%; the amount of compound 2 produced and the volume of the reaction vessel are scaled up or down accordingly.

B. A method for preparing compound 3:

0.0041mol of aro (hetero) cyclohydrazide 2 was added to an absolute ethanol solution of KOH (0.46g, 0.0082mol), and CS (0.74mL, 0.0123mol) was added dropwise to the solution under ice-bath conditions₂Heating the solution to reflux, monitoring the reaction process by TCL (thermal transfer chromatography), after the reaction is finished, decompressing and rotary-distilling the solvent to obtain a crude product, namely potassium salt of aryl (hetero) ring-3-oxadiazole sulfydryl, continuously refluxing the potassium salt in 3mL of 80% hydrazine hydrate solution for about 4 hours, then pouring the reaction solution into 200mL of ice water for dissolving, adjusting the pH value of the solution to about 5 by using 10% HCl to generate yellow precipitate, decompressing and filtering, and drying in a vacuum drying oven overnight to obtain 4-amino-5-sulfydryl-1, 2, 4-triazole compound 3, wherein the yield is 70-82%; the amount of compound 3 produced and the volume of the reaction vessel are scaled up or down accordingly.

C. A method for preparing compound 4:

in a dry 50mL round bottom flask, 0.0025mol of compound 3, 5mL of anhydrous ethanol solvent, 1.05mL of triethylamine, 0.0030mol of bromomethyl aryl (hetero) cyclic derivative selected from: heating a system to reflux by 1-bromomethyl-2, 4-dichlorobenzene, 2-bromomethylpyridine, 4-bromomethyl-3, 5-dimethylisoxazole, 3-chloromethyl-1, 2, 4-triazoline-5-one and bromomethyl cyclopropane, monitoring the reaction process by TLC, decompressing and distilling a solvent after the reaction is finished, dissolving a crude product by using 80mL of dichloromethane, washing by using 50mL of saturated saline solution, carrying out extraction separation, drying an organic layer by using anhydrous sodium sulfate, carrying out suction filtration and decompression and rotary distillation on the solvent, carrying out silica gel column chromatography purification on the crude product by using 200-300 meshes to obtain an eluent of dichloromethane and ethyl acetate, wherein the volume ratio is 10:1-50:1 and the yield is 85-97% according to different products, and obtaining the 1,2, 4-triazolylamino derivative 4.

D. A method for preparing compound 5:

0.7 mmole of 1,2, 4-triazolylamino derivative 4 was dissolved in 4mL of glacial acetic acid solvent, 0.7 mmole of an aromatic (hetero) cyclic formaldehyde was added, said aromatic (hetero) cyclic formaldehyde being selected from: heating a system to reflux by using 5-chloro-2-fluorobenzaldehyde, 4-nitrobenzaldehyde, 5-methylfuran-2-aldehyde and 2-thiophenecarboxaldehyde, monitoring the reaction process by using TCL (thermal transfer chromatography), decompressing and distilling to remove a solvent after the reaction is finished, purifying a crude product by using 200-300-mesh silica gel column chromatography, and separating and purifying to obtain the 1,2, 4-triazole Schiff base thioether compound 5. The eluent is dichloromethane and methanol, the volume ratio is 50: 1-100: 1 according to different products, the yield is 70-95%, and the preparation amount of the compound 5 and the volume of a reaction container are enlarged or reduced according to corresponding proportion.

E. The herbicidal activity of the 1,2, 4-triazole schiff base thioether derivative 5 of the invention is determined as follows:

the herbicidal activity of the 1,2, 4-triazole Schiff base thioether derivative 5 adopts a small cup method and a spray treatment method, and the method comprises the following specific steps: 20 mg of the sample was dissolved in 1 ml of N, N-dimethylformamide and diluted to 200. mu.g/ml with an aqueous solution containing a quantity of Tween 80 emulsifier. In the small cup method, seeds with consistent germination are picked by tweezers and evenly placed on filter paper sheets in a small beaker of 50ml, 10 seeds are placed in each cup, each treatment is repeated for 3 times, and a pipettor is used for sucking 1 ml of medicine liquid drops to the filter paper sheets. All treatments were placed in a climatic chamber for incubation at 25 + -0.5 deg.C with 60 + -5% humidity and light intensity with a day-to-day ratio of 16: 8. Measuring root length and stem length 7 days after treatment, and calculating rootInhibition rate and stem inhibition rate. The concentration used by the stem leaf spray method was 90 grams active content per hectare. In the stem and leaf treatment method, when the dicotyledonous weeds grow to the two leaf stage, the monocotyledonous weeds grow toDuring the leaf period, the test agent is uniformly sprayed on the weed leaves by using a walking spray tower, a solution without a sample is used as a blank control, each treatment is repeated for 3 times, the treated weeds are cultured in a climatic chamber, and the inhibition degree of the sample on the weed growth is investigated by using an absolute value method after 7 days. The test plants are the species of most typical weeds actually occurring in the field in agricultural production in China, and the names of the test plants are as follows: the latin name of the crabgrass is Digitaria sanguinalis L, Amaranthus retroflexus L.

The invention has the beneficial effects that: 1,2, 4-triazole Schiff base thioether derivative 5 is subjected to derivative synthesis, and the 1,2, 4-triazole Schiff base thioether derivative 5 is subjected to screening of herbicidal activity.

The synthesis, biological activity and application of 1,2, 4-triazole schiff base thioether derivative 5 are more specifically illustrated by specific preparation and biological activity determination examples, which are only used for specifically illustrating the invention and not limiting the invention, in particular, the biological activity is only illustrated and not limiting the patent, and the specific implementation modes are as follows:

example 1: the preparation method of the compound 2 comprises the following steps:

firing in 50ml single round bottomIn a bottle, 0.60mL of 80% hydrazine hydrate solution and 0.0041mol of methyl aryl (hetero) cyclic formate 1 are sequentially added, wherein the methyl aryl (hetero) cyclic formate is selected from the following components: heating a system to reflux by using 2-picolinic acid methyl ester and thiophene-3-formic acid methyl ester, monitoring the reaction process by using TCL (thermal transfer chromatography), stopping the reaction after reacting for about 5 hours, cooling the system to room temperature, adding a small amount of absolute ethyl alcohol into a reaction solution, carrying out reduced pressure rotary evaporation to remove redundant hydrazine hydrate, recrystallizing the residual solid in the absolute ethyl alcohol to obtain a white solid, and drying in a vacuum drying oven to obtain the aromatic heterocyclic hydrazide 2 with the yield of 85-90%; when R is¹For 3-thienyl, the nuclear magnetic data are as follows:¹H NMR(CD₃OD,400 MHz). delta.8.02-8.01 (m,1H),7.48-7.47(m, 2H). The amount of compound 2 produced and the volume of the reaction vessel are scaled up or down accordingly.

Example 2: a method for preparing compound 3:

0.0041mol of aro (hetero) cyclohydrazide 2 was added to an absolute ethanol solution of KOH (0.46g, 0.0082mol), and CS (0.74mL, 0.0123mol) was added dropwise to the solution under ice-bath conditions₂Heating the solution to reflux, monitoring the reaction process by TCL (thermal transfer chromatography), after the reaction is finished, decompressing and rotary-distilling the solvent to obtain a crude product, namely potassium salt of aryl (hetero) ring-3-oxadiazole sulfydryl, continuously refluxing the potassium salt in 3mL of 80% hydrazine hydrate solution for about 4 hours, then pouring the reaction solution into 200mL of ice water for dissolving, adjusting the pH value of the solution to about 5 by using 10% HCl to generate yellow precipitate, decompressing and filtering, and drying in a vacuum drying oven overnight to obtain 4-amino-5-sulfydryl-1, 2, 4-triazole compound 3, wherein the yield is 70-82%; when R is¹For 3-thienyl, the nuclear magnetic data are as follows:¹H NMR(CD₃cl,400MHz): δ 8.22(d, J ═ 2.0Hz,1H),7.44-7.39(m,2H),4.50(s, 2H). The amount of compound 3 produced and the volume of the reaction vessel are scaled up or down accordingly.

Example 3: a method for preparing compound 4:

in a dry 50mL round bottom flask, 0.0025mol of compound 3, 5mL of anhydrous ethanol solvent, 1.05mL of triethylamine, 0.0030mol of bromomethyl aryl (hetero) cyclic derivative selected from: 1-bromomethyl-2, 4-dichlorobenzene, 2-bromomethylpyridine, 4-bromomethyl-3, 5Heating and heating dimethyl isoxazole, 3-chloromethyl-1, 2, 4-triazoline-5-one and bromomethyl cyclopropane to reflux, monitoring the reaction process by TLC, decompressing and distilling a solvent after the reaction is finished, dissolving a crude product by using 80mL of dichloromethane, washing by using 50mL of saturated saline solution, extracting and separating, drying an organic layer by using anhydrous sodium sulfate, performing suction filtration and decompressing and distilling on the solvent, purifying the crude product by using 200-300-mesh silica gel column chromatography to obtain a 1,2, 4-triazolamino derivative 4, wherein an eluent is dichloromethane and ethyl acetate, the volume ratio is 10:1-50:1 according to different products, the yield is 85-97%, and when R is different from R, the yield is 10:1-50:1¹Is 3-thienyl, R²For 2, 4-dichlorophenyl, the nuclear magnetic data are as follows:¹H NMR(CD₃cl,400MHz): δ 8.22(d, J ═ 2.0Hz,1H),7.78(d, J ═ 4.8Hz,1H),7.44-7.39(m,3H),7.16-7.13(m,1H),4.50(s,2H),4.49(s, 2H). The amount of compound 4 produced and the volume of the reaction vessel are scaled up or down accordingly.

Example 4: a method for preparing compound 5:

0.7 mmole of 1,2, 4-triazolylamino derivative 4 was dissolved in 4mL of glacial acetic acid solvent, 0.7 mmole of an aromatic (hetero) cyclic formaldehyde was added, said aromatic (hetero) cyclic formaldehyde being selected from: heating a system to reflux by using 5-chloro-2-fluorobenzaldehyde, 4-nitrobenzaldehyde, 5-methylfuran-2-aldehyde and 2-thiophenecarboxaldehyde, monitoring the reaction process by using TCL (thermal transfer chromatography), decompressing and distilling to remove a solvent after the reaction is finished, purifying a crude product by using 200-300-mesh silica gel column chromatography, and separating and purifying to obtain the 1,2, 4-triazole Schiff base thioether compound 5. The eluent is dichloromethane and methanol, the volume ratio is 50: 1-100: 1 according to different products, the yield is 70-95%, and nuclear magnetic data are as follows:¹H NMR(400MHz,CDCl₃) δ 8.69(s,1H),7.92(d, J ═ 4.8Hz,2H),7.53-7.55(m,1H),7.42(s,1H),7.37-7.32(m,2H),7.18-7.11(m,2H),4.50(s, 2H). The amount of compound 5 produced and the volume of the reaction vessel are scaled up or down accordingly. The physicochemical and structural parameters of compound 5 are shown in table 1.

Example 5: the herbicidal activity test results of the 1,2, 4-triazole schiff base thioether derivative 5 of the present invention are as follows:

the common names of weeds tested in the present invention are as follows: the latin name of the crabgrass is Digitaria sanguinalis L, Amaranthus retroflexus L. These weeds are well-represented and can represent the majority of weeds occurring in the field in agricultural production. The weeding activity test adopts a small cup method and a stem leaf treatment method.

The result of the small cup method is shown in the table 2, and the result shows that the 1,2, 4-triazole Schiff base thioether derivative 5 synthesized by the invention has good herbicidal activity on crab grass and redroot amaranth at 200 micrograms/ml.

Among them, compounds 5ah, 5av, 5aw, 5bd showed better herbicidal activity than the control agents. The root inhibition rates of 5ah, 5av and 5aw to the large crabgrass are respectively about 93%, 92% and 96%, the root inhibition rates are superior to those of control medicaments of flumioxazin (71%) and chlortoluron (90%), and the root inhibition rates have better weeding effect on the large crabgrass; the root inhibition rates of 5av, 5aw, 5bd, 5bg, 5bh and 5bj on the redroot amaranth respectively reach about 92%, 91%, 86%, 83%, 85% and 83%, are superior to that of a control medicament flumioxazin (82%) and chlortoluron (25%), and have better weeding effect on the redroot amaranth.

Under the condition that the effective content is 90 g/hectare, part of the compounds have good weeding effect by a stem and leaf spraying method.

The stem and leaf spraying results are shown in table 3, and the results show that the compounds 5ah, 5ai, 5ak, 5av, 5aw and 5az have good weeding effect on crabgrass, the fresh weight inhibition rates of the compounds on the crabgrass respectively reach about 88%, 90%, 89%, 91%, 89% and 88%, and the control effects of the compounds are respectively superior to the control effects of commercial herbicides flumioxazin (86%) and chlortoluron (65%). The inhibition rates of 5ak, 5av and 5aw on the fresh weight of the amaranthus retroflexus respectively reach about 91%, 92% and 91%, and the control effect is superior to that of commercial herbicides flumioxazin (89%) and chlortoluron (89%).

In conclusion, the compounds 5ah, 5av, 5aw, 5bd, 5bg, 5bh, 5bj, 5ai, 7ak and 5az have good herbicidal activity, wherein the compounds 5ah, 5av and 5aw show excellent herbicidal activity in the treatment of the cup method and the spray treatment of stems and leaves, and have good development prospects.

Example 3: the 1,2, 4-triazole Schiff base thioether derivative 5 disclosed by the invention is applied to the preparation of a compound herbicide by combining with an agriculturally acceptable auxiliary agent and any one or more of the following commercial herbicides:

the commercial herbicide is selected from nicosulfuron, tribenuron-methyl, cinosulfuron, sulfometuron-methyl, penoxsulam, alachlor, acetochlor, butachlor, metolachlor, 2-methyl-4-chloro, trifluralin, mesotrione, topramezone, pendimethalin, atrazine, prometryn, cyanazine, ametryn, metribuzin, aclonifen, oxyfluorfen, acifluorfen, lactofen, fluorofen, pyraflufen-ethyl, imazapyr, imazaquin, imazamox, imazaquin, pyribenzoxim, imazapyr, bentazon, pyrazofen-ethyl, pyraflufen-ethyl, pyribenzoxim-methyl, propaferon, betasol, propaferin, swamp, pyraclonil, cockspur grass, dicarb, thiobac, thiocarb, thion, halofop-methyl, quinoa, -methyl, thiabendazole, benazolin, dithiopyr, fluazinone, thiazopyr, diflufenzopyr, paraquat, glyphosate, anilofos, flumiclorac, flumioxazin, fluthiacet, metribuzin, pyraflufen, tralkoxydim, carfentrazone, isoxaflutole, bromoxynil, and the like; the total mass percentage content of the 1,2, 4-triazole Schiff base thioether derivative 5 in the compound herbicide is 1% -90%, and the mass percentage of the 1,2, 4-triazole Schiff base thioether derivative 5 to the commercial herbicide is 1% -99% -1%; the formulation suitable for the compound herbicide is any one of wettable powder, microcapsule suspending agent, dispersible liquid formulation, dispersible solid formulation, seed treatment emulsion, aqueous emulsion, large granule, microemulsion, oil suspending agent, water soluble granule, soluble concentrate, water dispersible granule, poison grain, aerosol, sustained release block, capsule granule, dry-mixed seed powder, missible oil, electrostatic spray, aqueous oil-in-oil emulsion, oil-in-water emulsion, aerosol can, fine granule, aerosol candle, aerosol cylinder, aerosol stick, seed treatment suspending agent, aerosol tablet, aerosol pill, gas generating agent, drift powder, ointment, hot fogging concentrate, solid/liquid mixed package agent, liquid/liquid mixed package agent, cold fogging concentrate, solid/solid mixed package agent, medicinal paint, seed treatment liquid, microgranule, oil dispersible powder, colloid, pour-on agent, smearing agent, Suspending emulsion, film-forming oil agent, soluble powder, seed treatment water-soluble powder, ultra-low volume suspending agent, tracing powder, ultra-low volume liquid, steam releasing agent, and wet-mixed seed water-dispersible powder; the plant suitable for the compound herbicide is selected from rice, wheat, barley, oat, corn, sorghum, sweet potato, cassava, soybean, sweet broad bean, pea, mung bean, small bean, cotton, silkworm, peanut, rape, sesame, sunflower, beet, sugarcane, coffee, cocoa, ginseng, fritillaria, rubber, coconut, oil palm, sisal, tobacco, tomato, pepper, radish, cucumber, cabbage, celery, tuber mustard, beet, rape, shallot, garlic, watermelon, melon, cantaloupe, papaya, apple, orange, peach, tea, potherb, bamboo shoot, hop, pepper, banana, papaya, orchid, bonsai; the compound herbicide is suitable for controlling weeds and is selected from: grassy weeds: crab grass, green bristlegrass herb, goosegrass herb, barnyard grass, moleplant seed, tiger tail grass, wild oat, teff grass, golden green bristlegrass herb, long silvergrass club grass, amur foxtail and the like; broad-leaved weeds such as Amaranthus retroflexus, herba Portulacae, fructus Chenopodii, herba Desmodii Trifoliatae, herba Acalyphae, herba Xanthii, Ambrosia, piemarker, Kochiae fructus, herba Solani Nigri, herba Spinaciae, herba Stellariae, herba Moslae, herba Ecliptae, herba seu radix Valerianae, herba Convolvuli Alsinoides, and semen Cuscutae; cyperaceae weeds such as herba Tagetis Erectae, herba Cyperi Erectae, herba Salsolae Collinae, herba Alii Fistulosi, etc.

TABLE 1 chemical Structure and physicochemical parameters of 1,2, 4-triazole Schiff base thioether derivative 5 of the present invention

TABLE 2 microcup herbicidal Activity of 1,2, 4-triazole Schiff base thioether derivative 5 of the present invention (inhibition rate of 200. mu.g/ml/%)

TABLE 3 herbicidal Activity of foliage spray of 1,2, 4-triazole Schiff base thioether derivative 5 of the present invention (90 g active content/hectare inhibition/%)

Compound (I)	Tang style food	Amaranthus retroflexus (lour.) Merr	Compound (I)	Tang style food	Amaranthus retroflexus (lour.) Merr
						5aa	59±3	53±2	5at	66±2	61±2
5ab	63±1	47±2	5au	58±3	57±2
						5ac	64±2	59±2	5av	91±3	92±2
5ad	82±1	67±3	5aw	89±2	91±3
						5ae	58±2	54±2	5ax	83±3	67±3
5af	61±2	53±3	5ay	66±2	59±3
						5ag	55±3	59±1	5az	88±2	69±2
5ah	88±2	82±3	5ba	71±3	65±3
						5ai	90±3	82±2	5bb	70±2	73±1
5aj	55±2	59±2	5bc	63±2	83±3
						5ak	89±2	91±3	5bd	79±2	59±4
5al	63±3	61±2	5be	62±3	65±2
						5am	56±2	54±3	5bf	72±3	84±3
5an	71±1	76±2	5bg	78±3	86±1
						5ao	64±2	59±3	5bh	69±1	62±1
5ap	62±3	59±3	5bi	74±3	71±2
						5aq	81±3	69±3	5bj	68±1	75±2
5ar	75±3	56±3	Flumioxazin	86±3	89±3
						5as	69±2	67±3	Green wheat dragon	65±2	89±1