Substituted 3-(pyrid-2-yl)anilino derivatives and their use in herbicides

Abstract

The present application relates to the chemical and pesticide technical field, and particularly relates to a substituted 3-(pyridine-2-yl) aniline derivative and application thereof in weeding. The substituted 3-(pyridine-2-yl) aniline derivative provided by the present application has good weeding effect on weeds such as amaranthus retroflexus, abutilon theophrasti, medicago sativa, euphorbia heterophylla, digitaria sanguinalis and lolium rigidum, and good safety to crops. The compound 4 has good prevention effect on annual weeds in winter wheat field, including brome, cylindrical caprine grass, and anthriscus sylvester, and the prevention effect gradually increases with the increase of the pesticide dose. The compound 4 is higher than the commercial drug triflurole and 43% dimethyl bistrifluoro suspension emulsion + 30 g / L methyldisulfuron dispersible oil suspension in the final yield increase rate of wheat crops, and thus has good agricultural application prospect and development value.

Description

Technical Field

[0001] This invention relates to the fields of chemical and pesticide technology, and in particular to a substituted 3-(pyridin-2-yl)phenylamino derivative and its application in weed control. Background Technology

[0002] The growth of weeds seriously threatens the growth of agricultural productivity. They compete with crops for sunlight, water and nutrients, causing crop yield reduction and quality decline. They also become breeding grounds for pests and diseases. Some weeds release allelochemicals that inhibit crop growth, interfere with farming operations such as plowing and harvesting, increase production costs, and cause great losses to agricultural production. Therefore, weed control has always been an important challenge in agricultural production. As a result, the widespread use of herbicides has made a significant contribution to ensuring grain production.

[0003] PPO (protoporphyrinogen oxidase) inhibitor herbicides primarily inhibit protoporphyrinogen oxidase (PPO) in the chlorophyll-heme synthesis pathway of plants. The substrate protoporphyrinogen-IX cannot be properly converted, accumulating in large quantities and leaking into the cytoplasm, where it is oxidized to the photosensitive substance protoporphyrin-IX. Under light conditions, this produces singlet oxygen, triggering membrane lipid peroxidation, damaging cell membrane structure, and causing leakage of cell contents. Weed leaves quickly show scorching, browning, and necrosis, ultimately leading to plant death. PPO inhibitor herbicides are fast-acting; under sufficient light, weeds can be scorched and killed in a short time. They have a broad spectrum of weed control, and some agents also have pre-emergence and post-emergence foliar treatment effects. Their specific targets prevent cross-resistance with herbicides such as ALS and glyphosate, which is beneficial for controlling resistant weeds. Most varieties have short soil residues, good safety for subsequent crops, and can still exert weed-control activity at low temperatures, making them suitable for various crop fields.

[0004] Among traditional non-selective herbicides, paraquat, glufosinate, and glyphosate are the most representative. However, paraquat's sale and use have been gradually restricted due to its high toxicity. Meanwhile, glufosinate and glyphosate have gradually led to problems such as weed resistance due to long-term and large-scale use. Therefore, finding new, efficient, broad-spectrum herbicides that are safe for crops and environmentally friendly has become a major challenge in pesticide development. Summary of the Invention

[0005] To address the aforementioned problems, this invention provides a substituted 3-(pyridin-2-yl)phenylamino derivative and its application in weed control, thereby resolving issues such as poor weed resistance and crop safety of existing herbicides, poor control of annual weeds in winter wheat fields, and poor safety for wheat.

[0006] To achieve the above objectives, the present invention provides the following technical solution:

[0007] This invention provides a substituted 3-(pyridin-2-yl)phenylamino derivative, wherein the substituted 3-(pyridin-2-yl)phenylamino derivative is compound 1, compound 2, compound 3, or compound 4, and has the following structural formula:

[0008] .

[0009] The present invention also provides the application of the substituted 3-(pyridin-2-yl)phenylamino derivatives described in the above technical solution in weed control.

[0010] Preferably, the grass includes broadleaf weeds and / or grasses.

[0011] Preferably, the broadleaf weeds include one or more of the following: amaranth, velvetleaf, alfalfa, and shepherd's purse.

[0012] Preferably, the grassy weeds include one or more of barnyard grass, crabgrass, ryegrass, bromegrass and goatgrass.

[0013] Preferably, the amount of the substituted 3-(pyridin-2-yl)phenylamino derivative used is 37.5~300 g ai / ha.

[0014] Preferably, the amount of the substituted 3-(pyridin-2-yl)phenylamino derivative used is 75~200 g ai / ha.

[0015] Preferably, the amount of the substituted 3-(pyridin-2-yl)phenylamino derivative used is 100~150 g ai / ha.

[0016] The present invention also provides a herbicide comprising the substituted 3-(pyridin-2-yl)phenylamino derivative described above and a carrier acceptable in the field of pesticides.

[0017] Preferably, the grass includes one or more of the following: amaranth, velvetleaf, alfalfa, shepherd's purse, barnyard grass, crabgrass, ryegrass, bromegrass, and goatgrass.

[0018] The beneficial effects of this invention are:

[0019] The substituted 3-(pyridin-2-yl)phenylamino derivatives provided by this invention exhibit good herbicidal effects against weeds such as amaranth, velvetleaf, alfalfa, barnyard grass, crabgrass, and ryegrass, and also demonstrate good safety for crops. Compound 4, in particular, shows good control efficacy against annual weeds in winter wheat fields, including bromegrass, goatgrass, and shepherd's purse, with efficacy gradually increasing with increasing dosage. Compound 4 also demonstrates higher yield increases in wheat crops than the commercial herbicides trifluralin and 43% dimethyl diflubenzuron suspension emulsion + 30 g / L mesosulfuron-methyl dispersible oil suspension, thus possessing promising agricultural application prospects and development value. Attached Figure Description

[0020] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the accompanying drawings used in the embodiments will be briefly described below.

[0021] Figure 1 Symptoms of herbicide damage to wheat plants 15 days after application of compound A4. Detailed Implementation

[0022] This invention provides a substituted 3-(pyridin-2-yl)phenylamino derivative, wherein the substituted 3-(pyridin-2-yl)phenylamino derivative is compound 1, compound 2, compound 3, or compound 4, and has the following structural formula:

[0023] .

[0024] This invention also provides the application of the substituted 3-(pyridin-2-yl)phenylamino derivative described in the above-mentioned technical solution in weed control. In this invention, the weeds preferably include broadleaf weeds and / or grass weeds. In this invention, the broadleaf weeds preferably include one or more of *Amaranthus retroflexus*, *Abutilon theophrasti*, alfalfa, and *Desmodium triquetrum*. In this invention, the grass weeds preferably include one or more of barnyard grass, crabgrass, ryegrass, bromegrass, and *Aegilops cylindrica*. In this invention, the amount of the substituted 3-(pyridin-2-yl)phenylamino derivative used is preferably 37.5~300 g ai / ha. In this invention, the amount of the substituted 3-(pyridin-2-yl)phenylamino derivative used is preferably 75~200 g ai / ha. In this invention, the amount of the substituted 3-(pyridin-2-yl)phenylamino derivative used is preferably 100~150 g ai / ha.

[0025] This invention also provides a herbicide comprising the substituted 3-(pyridin-2-yl)phenylamino derivative described in the above-described technical solution and a carrier acceptable in the pesticide field. In this invention, the grass preferably comprises one or more of the following: amaranth, velvetleaf, alfalfa, shepherd's purse, barnyard grass, crabgrass, ryegrass, bromegrass, and Aegilops cylindrica.

[0026] To further illustrate the present invention, the following detailed description is provided in conjunction with embodiments, but these should not be construed as limiting the scope of protection of the present invention.

[0027] Example 1

[0028] Test reagents:

[0029] A1 (compound 1), A2 (compound 2), A3 (compound 3) (all of the above are compounds of the present invention, and the synthesis method is as follows CN117263852A), A4 (compound 4) (preparation method is as follows);

[0030] The preparation method of compound 4 includes the following steps:

[0031] (1) Synthetic route of intermediate C:

[0032] Compound A (4.00 g, 12.30 mmol) (synthesized according to CN117263852A) was added to 40 mL of 6 M hydrochloric acid (HCl) solution at 0 °C. Subsequently, 10 mL of sodium nitrite (NaNO2, 1.02 g, 14.77 mmol) aqueous solution was added dropwise to the reaction mixture. After the addition was complete, the reaction mixture was stirred at 0 °C for 30 minutes to generate a diazonium salt solution of compound B. Next, ethyl acetoacetate (2.40 g, 18.44 mmol) and potassium acetate (KOAc, 12.07 g, 122.94 mmol) were added to a reaction flask containing a mixture of 30 mL water and 90 mL ethanol (EtOH). Then, the freshly prepared diazonium salt solution was added dropwise to this mixture while maintaining the reaction temperature at 0 °C. After the addition was complete, the reaction mixture was continuously stirred at 0 °C for 2 hours. After the reaction was completed, the mixture was filtered, the resulting solid was washed with water and dried to obtain the crude product compound C, which was directly used in the next reaction.

[0033] (2) Synthetic route of compound D:

[0034] Compound C (2.30 g, 4.93 mmol) was dissolved in 18 mL of N,N-dimethylformamide dimethyl acetal (DMF-DMA) and reacted at 80 °C for 2–6 hours. After the reaction was complete, the system was allowed to cool naturally to room temperature, and then the solvent was removed under reduced pressure. The residue was purified by silica gel column chromatography using petroleum ether and ethyl acetate (1:1, v / v) as the elution system to obtain compound D.

[0035] (3) Synthetic route of intermediate E:

[0036] Compound D (2.19 g, 4.60 mmol) was dissolved in a mixture of methanol (MeOH, 20 mL) and water (20 mL) at room temperature. Lithium hydroxide (LiOH, 550.64 mg, 22.99 mmol) was added to this solution, and the reaction mixture was reacted at 30 °C for 3 h. After the reaction was complete, methanol was removed under reduced pressure, and the reaction mixture was cooled to 0 °C. The pH was adjusted to 2–3 using 6 M hydrochloric acid solution. Subsequently, the mixture was extracted with DCM, the organic layer was dried over anhydrous sodium sulfate (Na₂SO₄), filtered, and dichloromethane was evaporated under reduced pressure to give compound E.

[0037] (4) Synthetic route of intermediate F:

[0038] Compound E (1.69 g, 3.77 mmol) was dissolved in ultradry dichloromethane (DCM), and oxaloyl chloride (478.62 μL, 5.66 mmol) was added. After reacting at room temperature for about half an hour, 2 drops of N,N-dimethylformamide (DMF) were added, and the reaction system was stirred for another 2 hours at room temperature to ensure the reaction was complete. The reaction mixture was then concentrated under vacuum to give compound F.

[0039] (5) Synthetic route of target compound G (compound 4)

[0040] Triethylamine (Et3N, 0.15 g, 1.5 mmol) was added to a solution of dichloromethane (DCM, 3 mL) containing n-butanol (1.1 mmol) at 0 °C. After stirring at 0 °C for 10 min, compound F (1.0 mmol) was added, and the mixture was stirred at room temperature for 3 h. After the reaction was complete, product G (compound 4) was obtained by column chromatography using petroleum ether / ethyl acetate (5:1 to 1:1, v / v) as the elution system.

[0041] The compound characterization data are as follows:

[0042] N-(2-chloro-5-(3-chloro-5-(trifluoromethyl)pyridin-2-yl)-4-fluorophenyl) pro-pionamide (Compound 1):

[0043] Yield, 65%, white solid, melting point, 143.2-144.0 ℃.

[0044] 1H NMR (400 MHz, CDCl3) δ: 8.85 (d, J = 1.0 Hz, 1H), 8.59 (d, J = 7.1Hz, 1H), 8.05 (d, J = 1.5 Hz, 1H), 7.60 (s, 1H), 7.28 (s, 1H), 2.48 (q, J =7.5 Hz, 2H), 1.27 (t, J = 7.5 Hz, 3H).

[0045] 13 C NMR (101 MHz, CDCl3) δ: 171.84, 155.38, 154.93 (d, J = 251.7 Hz), 144.29 (q, J = 7.8, 3.9 Hz), 134.69 (q, J = 3.5 Hz), 132.15, 131.43 (d, J =3.1 Hz), 127.21 (q, J = 33.8 Hz), 124.68 (d, J = 15.8 Hz), 124.46, 123.53,122.57 (q, J = 273.4 Hz), 116.71 (d, J = 26.3 Hz), 30.90, 9.50.

[0046] 19 F NMR (377 MHz, CDCl3) δ: -62.32, -116.56.

[0047] HRMS (ESI, m / z) calcd. For C 15 H 10 Cl2F4N2O [M+Na]+ 403.0106,found:402.9998.

[0048] 1-(2-chloro-5-(3-chloro-5-(trifluoromethyl)pyridin-2-yl)-4-fluorophenyl)-3-ethylurea (Compound 2):

[0049] Yield, 60%, white solid, melting point, 197.8–199.0 °C.

[0050] 1H NMR (400 MHz, CDCl3) δ: 8.84 (dd, J = 1.8, 0.7 Hz, 1H), 8.32 (d, J =7.1 Hz, 1H), 8.04 (d, J = 1.5 Hz, 1H), 7.23 (d, J = 8.9 Hz, 1H), 6.70 (s,1H), 4.85 (t, J = 4.7 Hz, 1H), 3.30 (qd, J = 7.2, 5.6 Hz, 2H), 1.18 (t, J =7.2 Hz, 3H).

[0051] 13 C NMR (101 MHz, CDCl3) δ: 154.47, 154.31 (d, J = 249.5 Hz), 144.23 (q, J = 3.7 Hz), 134.69 (q, J = 3.5 Hz), 132.51 (d, J = 3.4 Hz), 132.15,127.12 (q, J = 31.1 Hz), 124.57 (d, J = 16.0 Hz), 124.41, 124.31, 123.17 (d,J = 2.7 Hz), 122.57 (q, J = 273.5 Hz), 116.63 (d, J = 26.2 Hz), 35.42, 15.23.

[0052] 19 F NMR (377 MHz, CDCl3) δ: -62.32, -118.71.

[0053] HRMS (ESI, m / z) calcd. For C 15 H 11 Cl2F4N3O [M+Na]+ 418.0215,found:418.0107.

[0054] N-((2-chloro-5-(3-chloro-5-(trifluoromethyl)pyridin-2-yl)-4-fluorophenyl)car-bamothioyl)pivalamide (compound 3):

[0055] Yield: 33%, pale yellow solid, melting point: 108.7-112.3 ℃.

[0056] 1H NMR (400 MHz, CDCl3) δ: 12.71 (s, 1H), 8.87 (d, J = 1.1 Hz, 1H), 8.63 (d, J = 7.1 Hz, 2H), 8.07 (d, J = 1.5 Hz, 1H), 7.36 (t, J = 7.6 Hz, 1H),1.33 (s, 9H).

[0057] 13 C NMR (101 MHz, CDCl3) δ: 179.41, 179.00, 156.94 (d, J = 254.4 Hz), 154.89, 144.40 (q, J = 3.8 Hz), 134.90 (q, J = 3.2 Hz), 132.19, 131.73 (d, J= 3.7 Hz), 130.21 (d, J = 10.2 Hz), 128.16 (d, J = 3.4 Hz), 127.27 (q, J =33.8 Hz), 124.01 (d, J = 16.1 Hz), 122.55 (q, J = 273.2 Hz), 117.43 (d, J =26.2 Hz), 40.10, 27.01 (3×C).

[0058] 19 F NMR (377 MHz, CDCl3) δ: -62.32, -112.46.

[0059] HRMS (ESI, m / z) calcd. For C 18 H 15 Cl2F4N3OS [M+Na]+ 490.0249,found:490.0141.

[0060] butyl1-(2-chloro-5-(3-chloro-5-(trifluoromethyl)pyridin-2-yl)-4-fluorophenyl)-4-oxo-1,4-dihydropyridazine-3-carboxylate (compound 4):

[0061] Yield: 71%, pale yellow solid, melting point: 91.7-93.8 ℃.

[0062] 1H NMR (400 MHz, CDCl3) δ: 8.85 (dd, J = 2.0, 0.9 Hz, 1H), 8.09 (dd, J= 2.0, 0.8 Hz, 1H), 7.95 (d, J = 8.0 Hz, 1H), 7.72 (d, J = 6.5 Hz, 1H), 7.45(d, J = 8.7 Hz, 1H), 6.69 (d, J = 8.0 Hz, 1H), 4.35 (t, J = 6.8 Hz, 2H), 1.75– 1.68 (m, 2H), 1.47 – 1.37 (m, 2H), 0.92 (t, J = 7.4 Hz, 3H).

[0063] 13 C NMR (101 MHz, CDCl3) δ: 167.3, 162.5, 159.4 (d, J = 259.1 Hz), 153.6, 150.3, 144.6 (q, J = 3.8 Hz), 142.6, 137.2 (d, J = 3.8 Hz), 135.0 (q,J = 3.5 Hz), 132.3, 132.2 (d, J = 10.9 Hz), 130.5 (d, J = 4.6 Hz), 127.8 (q,J = 34.0 Hz), 125.8 (d, J = 16.8 Hz), 122.4 (q, J = 273.4 Hz), 119.8, 118.7(d, J = 26.6 Hz), 66.2, 30.5, 19.0, 13.7.

[0064] 19 F NMR (377 MHz, CDCl3) δ: -62.4, -106.3.

[0065] HRMS (ESI): calcd for C 21 H 15 Cl2F4N3O3Na+ [M + Na]+ 526.0319, found:526.0308.

[0066] Control drug:

[0067] Trifluralin, 43% dimethyl difluralin suspension emulsion (PD20182422) + 30 g / L mesosulfuron-methyl dispersible oil suspension (PD20070051);

[0068] Test subjects:

[0069] The main targets for prevention and control include weeds such as amaranth, velvetleaf, alfalfa, barnyard grass, crabgrass, ryegrass, bromegrass, goatgrass, and shepherd's purse, as well as crops such as rice, wheat, corn, soybean, cotton, and peanut.

[0070] Experimental Design:

[0071] Herbicidal activity and crop safety tests: Six representative weeds (Amaranthus retroflexus, Abutilon theophrasti, Alfalfa, Barnyardgrass, Crataegus pinnatifida, and Lorraine) were selected as test subjects. Post-emergence herbicidal activity was tested using a spray method, with the common herbicide trifluralin as a control. All target compounds were within the range of 37.5-150 g ai ha -1 Post-emergence herbicidal activity was tested at specific dosages. Compounds exhibiting high herbicidal activity were further tested for herbicidal efficacy against annual weeds in winter wheat fields and crop safety.

[0072] The target compound was dissolved in N,N-dimethylformamide to prepare a high-concentration stock solution, which was then diluted with 0.1% Tween-80 water to the desired concentration. Spray dosage (active ingredient, g ai ha) -1 The calculation method involves dividing the mass of the sprayed inhibitor by the top surface area of ​​the flowerpot. Before testing, flowerpots with a diameter of 7 cm were selected, and approximately 6-10 weed seeds were sown, covered with about 0.5 cm of soil, and cultivated in a greenhouse for two weeks. During the experiment, the temperature was maintained at 28 ± 1 ℃, and the air humidity was maintained at approximately 60%. For the post-emergence herbicidal activity test, weeds with uniform growth were treated with a diluted inhibitor emulsion, and a negative control group was directly used with an inhibitor-free solvent (DMF + Tween-80). Each treatment was repeated three times, and the herbicidal activity results were visually evaluated 14 days after treatment. A similar crop safety test used a pot spray method for herbicidal activity testing, using trifluralin as a control, with a test dose of 75 to 150 g ai ha. -1 The crop safety of the compound was assessed 14 days after application, based on the degree of crop damage.

[0073] Efficacy and safety tests of annual weed control in winter wheat fields: Compound A4 was treated to 5% A4 (compound 4), and the effective ingredient dosage was set at 100, 150, 200, and 300 g aiha. -1 The dosage of the control drug 5% trifluralin active ingredient was set at 150 g aiha. -1 The active ingredient dosage of 43% dimethyl disulfuron suspension (PD20182422) + 30 g / L mesosulfuron dispersible oil suspension (PD20070051) is 516 + 13.5 g aiha. -1 As shown in Table 1.

[0074] Table 1 Experimental Design

[0075]

[0076] Note: The dosage for mixing the medicine is 35 L / 667 m³. 2 .

[0077] Preparation of the medicine solution:

[0078] The test substance and control substance were prepared using a two-stage dilution method based on the calculated dosage of pesticide and water (both were increased by 20% to ensure the effectiveness of spraying). The test substance was weighed using a balance and placed in a 500 mL measuring cup (pre-filled with 200-300 mL of water), and stirred thoroughly with a glass rod. A certain amount of water was first poured into a manual backpack sprayer, followed by the diluted pesticide solution from the measuring cup. The glass rod and measuring cup were then rinsed 3-4 times with the remaining water before being poured into the sprayer. The sprayer was then capped, shaken thoroughly, and set aside.

[0079] Community design:

[0080] The experiment consisted of 8 treatments, each replicated 4 times, using a randomized block design. The experimental plots were arranged in a rectangular pattern, with a plot area of ​​length × width = 4 m × 5 m = 20 m. 2 .

[0081] Application method:

[0082] This experiment was conducted during a windless or lightly windy period on the same day. A conventional manual backpack electric sprayer was used, following the order of first a blank control, then the test pesticide, and finally the control pesticide. The test pesticides were applied in order of increasing dosage. During spraying, the nozzle was kept 20 cm vertically from the wheat and target weed canopy. Before switching to the control pesticide after spraying the test pesticide, and between spraying different control pesticides, the sprayer (including the pipeline, spray bar, nozzle, and all other parts that came into contact with the pesticide) was thoroughly cleaned. Before application, the sprayer flow rate is measured. Based on the sprayer flow rate and the amount of pesticide to be applied, the spraying time for each plot is determined. The plot is then rationally divided into spray paths based on the plot width and sprayer width, determining the application path and route length. The sprayer's walking speed is then trained, and the walking frequency is controlled by adjusting the pacing device. During application, the pesticide is applied evenly while strictly adhering to this walking speed and frequency to avoid overlapping or missed areas. The spraying deviation between repeated plots of the same treatment should not exceed 10%, and care should be taken to avoid pesticide drift between plots. After application, the deviation between the theoretical and actual pesticide application volume for each treatment is measured. If the deviation exceeds ±10%, another plot must be selected for re-spraying.

[0083] Survey time, frequency, and methods:

[0084] Eight days after application, wheat plant height was measured, and any phytotoxic symptoms were observed. On the day of harvest, the impact of the herbicide on winter wheat growth was investigated. Fifty-seven days after application, weed control efficacy and fresh weight efficacy were assessed. During wheat harvest, sampling was conducted, and both numerical and visual observations were used to observe whether the herbicide caused phytotoxicity in winter wheat, recording the type and severity of the damage. Detailed descriptions of weed damage symptoms (such as growth inhibition, chlorosis, and malformation) were provided to accurately explain the herbicide's mechanism of action. An absolute number method was used, randomly selecting three survey points in each plot, with each point demarcated at 0.25 m. 2 For each quadrat, count the number of plants of each weed species in each quadrat and cut the above-ground parts to weigh their fresh weight. Calculate the plant control efficacy and fresh weight control efficacy of the herbicide treatment against the weeds according to Formula 1 and Formula 2 (as follows).

[0085] Formula 1, 2:

[0086] Table 2 Formulas 1 and 2

[0087]

[0088] During the harvest season, three survey points were randomly selected from each plot, with each point marked out at a depth of 0.25 m. 2 The quadrats were used to measure grain yield (grain moisture content 14.3%) after harvesting and threshing, and the yield was converted to kg / 667 m². 2 This means that, according to the calculation method in Formula 3, the yield increase rate of each herbicide treatment compared with manual weeding is calculated, and the impact of the tested herbicide on crop yield is evaluated.

[0089] Formula 3:

[0090] Table 3 Formula 3

[0091]

[0092] Post-emergence herbicidal activity test of the compound:

[0093] Table 4. Post-emergence herbicidal activity of substituted 3-(pyridin-2-yl)phenylamino derivatives

[0094]

[0095] a 0 indicates no weed-killing activity; 100 indicates complete weed killing.

[0096] Table 4 shows that the post-emergence herbicidal activity test results indicate that all four compounds exhibited good herbicidal activity, especially against broadleaf weeds. Compounds A3 and A4 showed better overall herbicidal activity against broadleaf weeds than the control herbicide trifluralin, even at 37.5 g aiha. -1 Both compounds exhibited good herbicidal activity against broadleaf weeds, but their activity against ryegrass was slightly lower. Compound A4, at 37.5 g ai / ha, still showed significant herbicidal activity against both tested broadleaf and grass weeds, and was significantly superior to the control herbicide trifluralin.

[0097] Post-emergence crop safety testing of the compound:

[0098] Table 5. Post-emergence crop safety of substituted 3-(pyridin-2-yl)phenylamino derivatives

[0099]

[0100] a 0 indicates no damage to the crop; 100 indicates complete crop death.

[0101] Table 5 shows that when the dosage of aiha is 75-150 g... -1 Compounds A1, A2, and A3 all showed good safety profiles in rice, wheat, corn, peanuts, and soybeans, and were superior to the commercial herbicide trifluralin. Compound A4 showed good safety profiles at application rates of 75-150 g aiha. -1 At that time, its crop safety for corn was comparable to that of the commercial pesticide trifluralin, and its crop safety for rice and wheat was relatively good, but slightly lower than that of the commercial pesticide trifluralin. Furthermore, its crop safety for peanuts, cotton, and soybeans was lower than that of the commercial pesticide trifluralin.

[0102] The plant control efficacy of compound A4 against major weeds in winter wheat fields:

[0103] Table 6. Control efficacy of 5%A4 against major weeds in winter wheat fields - 57 days after application. *

[0104]

[0105] * The same lowercase letter in the same column indicates that there is no significant difference at the α=0.05 significance level; ** The dosage of the medicine is 35L / 667m³. 2 .

[0106] As shown in Table 6, during the greening stage of winter wheat (when wheat has 2-3 tillers), the dosage of compound A1 in the formulation is 133-266 mL / 667 m 2(Dosage of active ingredient: 100-200 g aiha) -1 ), dilute with 35 L / 667 m 2 After uniform foliar spraying, the total control efficacy against major weeds such as bromegrass, shepherd's purse, and Aegilops crassirhizoma was 70.48%-88.59%; and the control efficacy gradually increased with increasing dosage. Specifically, the control efficacy was highest at a dosage of 200-266 mL / 667 m³. 2 The efficacy against weeds was comparable to that of the control agent 5% trifluralin, but lower than that of the treatment with 43% dimethyl diflubenzuron suspension emulsion + 30 g / L mesosulfuron-methyl dispersible oil suspension.

[0107] Fresh weight control efficacy of compound A4 against major weeds in winter wheat fields:

[0108] Table 7. Fresh weight control efficacy of 5% A4 against major weeds in winter wheat fields - 57 days after application. *

[0109]

[0110] * The same lowercase letter in the same column indicates that there is no significant difference at the α=0.05 significance level; ** The dosage of the medicine is 35L / 667m³. 2 .

[0111] As shown in Table 7, the dosage of compound A4 in the formulation is 133-266 mL / 667 mL. 2 (Dosage of active ingredient: 100-200 g aiha) -1 ), dilute with 35 L / 667 m 2 After uniform foliar spraying, the total fresh weight control efficacy against major weeds such as bromegrass, shepherd's purse, and goat's quarters was 86.70%-90.56%, and the efficacy gradually increased with the increase of the application dose. Overall, it was higher than the control treatment of 5% trifluralin alone, but lower than the treatment of 43% dimethyl diflubenzuron suspension emulsion + 30 g / L mesosulfuron-methyl dispersible oil suspension.

[0112] Effects of compound A4 on winter wheat growth and yield:

[0113] Table 8 Effects of compound 5%A4 on winter wheat growth and yield

[0114]

[0115] * The same lowercase letter in the same column indicates that there is no significant difference at the α=0.05 significance level; ** The dosage of the medicine is 35L / 667m³. 2.

[0116] Pesticide damage levels: Level 1: Crop growth is normal, with no symptoms of damage; Level 2: Slight pesticide damage to crops, less than 10%; Level 3: Moderate pesticide damage to crops, which can recover later and does not affect yield; Level 4: Severe pesticide damage to crops, which is difficult to recover and causes yield reduction; Level 5: Severe pesticide damage to crops, which cannot recover and causes significant yield reduction or crop failure.

[0117] Table 8 shows that 8 days after application, the plant height was not significantly different from that of the water control and the artificially treated plant. Compound A4 was applied at a dosage of 133-399 mL / 667 m³. 2 (Dosage of active ingredient: 100-300 g aiha) -1 ), dilute with 35 L / 667 m 2 After uniform foliar spraying, the yield of winter wheat per mu was significantly higher than that of the water control and comparable to that of manual weeding. The yield increase rate of compound A4 was -5.83% to 0.93%, which was significantly higher than that of the 5% trifluralin control and the 43% dimethyl diflubenzuron suspension emulsion + 30 g / L mesosulfuron dispersible oil suspension.

[0118] Safety of winter wheat, such as Figure 1 As shown. By Figure 1 It can be seen that the dosage of compound A4 is 133-399 mL / 667 mL. 2 (Dosage of active ingredient: 100-300 g aiha) -1 The results of observation 15 days after application showed that the pesticide treatment caused significant damage to wheat, mainly manifested as leaf burn and chlorosis. The damage gradually worsened with increasing dosage, similar to the symptoms of the control pesticide 5% trifluralin, but the damage was significantly lower than that of the treatment with 43% dimethyl diflubenzuron suspension emulsion + 30 g / L mesosulfuron-methyl dispersible oil suspension.

[0119] In summary, compounds A1, A2, A3, and A4 in this invention are effective when administered at a dosage of 37.5-150 g aiha. -1 All three compounds showed good herbicidal activity, especially against broadleaf weeds, and were effective against all weeds at a dosage of 75-150 g aiha. -1 Compound A4 showed good crop safety at application rates of 75-150 g.i.ha. -1 It showed good crop safety in corn and wheat; in subsequent wheat fields, compound A4 was applied at an effective dosage of 100-300 g aiha. -1At 57 days after application, the overall plant control efficacy, fresh weight control efficacy, wheat yield increase rate, and winter wheat safety were all superior to the commercial herbicide trifluralin. Among them, compound A4 was lower than the treatment of 43% dimethyl difluralin suspension emulsion + 30 g / L mesosulfuron-methyl dispersible oil suspension in terms of overall plant control efficacy and fresh weight control efficacy, but it was much higher than the treatment of 43% dimethyl difluralin suspension emulsion + 30 g / L mesosulfuron-methyl dispersible oil suspension in terms of yield increase rate and crop safety, showing good application prospects.

[0120] Although the above embodiments have provided a detailed description of the present invention, they are only some embodiments of the present invention, and not all embodiments. People can obtain other embodiments based on these embodiments without creative effort, and these embodiments all fall within the protection scope of the present invention.

Claims

1. A substituted 3-(pyridin-2-yl)phenylamino derivative, characterized in that, The substituted 3-(pyridin-2-yl)phenylamino derivative is compound 1, compound 2, compound 3, or compound 4, with the following structural formula: 。 2. The use of the substituted 3-(pyridin-2-yl)phenylamino derivative of claim 1 in weed control.

3. The application according to claim 2, characterized in that, The grasses include broadleaf weeds and / or grasses.

4. The application according to claim 3, characterized in that, The broadleaf weeds include one or more of the following: amaranth, velvetleaf, alfalfa, and shepherd's purse.

5. The application according to claim 3, characterized in that, The grassy weeds include one or more of barnyard grass, crabgrass, ryegrass, bromegrass, and chebulic goatgrass.

6. The application according to claim 2, characterized in that, The amount of the substituted 3-(pyridin-2-yl)phenylamino derivative used is 37.5~300 g ai / ha.

7. The application according to claim 6, characterized in that, The amount of the substituted 3-(pyridin-2-yl)phenylamino derivative used is 75~200 g ai / ha.

8. The application according to claim 7, characterized in that, The amount of the substituted 3-(pyridin-2-yl)phenylamino derivative used is 100~150 g ai / ha.

9. A herbicide, characterized in that, This includes the substituted 3-(pyridin-2-yl)phenylamino derivatives as described in claim 1, and carriers acceptable in the pesticide field.

10. The herbicide according to claim 9, characterized in that, The grasses include one or more of the following: amaranth, velvetleaf, alfalfa, shepherd's purse, barnyard grass, crabgrass, ryegrass, bromegrass, and goatgrass.

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