A fluorobenzothiazole diester compound and its uses

Abstract

The present invention provides a fluorobenzene benzothiazole diester compound, the structure of which is shown in general formula I: In the formula, R 1 is: H, F, CH 3 , CF 3 ; R 2 is: H, Cl, CF 3 ; R 3 is: H, C(CH 3 ) 3 ; R 4 is: H, Cl, CF 3 ; R 5 is: H, F. The compound of general formula I has a pesticidal effect on agricultural and forestry pests and can be used as an insecticide for the control of agricultural and forestry pests.

Description

[0001] Technical Field The present invention belongs to the field of insecticides in pesticides, and relates to a fluorobenzothiazole diester compound and its use for controlling pests in agriculture or forestry.

[0002] Background Art Pests in agriculture damage the growth of crops, resulting in reduced yields and degraded quality. Currently, the control of pests mainly relies on chemical pesticides. Due to the large and frequent use of insecticides, pests have developed serious resistance to them, leading to a series of problems such as increasing dosages, decreasing control efficacy, shortening of the effective period, and increasing agricultural residues. The development and application of new insecticides and acaricides with different action mechanisms are effective means to solve the resistance of pests. Fluorine-containing pesticides have received extensive attention due to their low dosage and high efficacy. Thiazole compounds also have commercial products in insecticides and acaricides, such as thiamethoxam, thiacloprid, clothianidin, hexythiazox, etc. The compound (I) of the present invention belongs to a fluorobenzothiazole diester compound, and the compound of formula I as described in the present invention and its use as an agricultural insecticide and acaricide have not been disclosed in the prior art.

[0003] Summary of the Invention The purpose of the present invention is to provide an insecticide with a novel structure, simple, safe and efficient synthesis method, which can be used for controlling pests in agriculture or forestry.

[0004] The technical solution of the present invention is as follows:

[0005] A fluorobenzothiazole diester compound, the structure of which is shown in the general formula I:

[0006] In the formula, R 1 is: H, F, CH 3 , CF 3 ; R 2 is: H, Cl, CF 3 ; R 3 is: H, C(CH 3 ) 3 ; R 4 is: H, Cl, CF 3 ; R 5 is: H, F.

[0007] The compound of general formula I of the present invention can be prepared by the following method:

[0008]

[0009]

[0010] In the formula, R 1 , R 2 , R 3 , R 4 , R 5 are the same as above. For the specific preparation method, see the synthesis examples of the present invention.

[0011] Table 1 lists the structures and appearances of the compounds of General Formula Ⅰ.

[0012] Table 1 Structures and Appearances of Compounds of General Formula Ⅰ

[0013]

[0014] Advantages and Positive Effects of the Present Invention:

[0015] The compounds (General Formula Ⅰ) of the present invention, as agricultural insecticides, have the advantages of novel structure, simple preparation, high efficiency, and environmental friendliness. The compounds of the present invention have excellent inhibitory and killing effects on Plutella xylostella. When the mass concentration is 100 mg / L, the lethality rate of Plutella xylostella at 1 h is 93%, and the rest reaches 100%; when the mass concentration is 10 mg / L, the lethality rates of Ⅰa, Ⅰd, and Ⅰf reach 100%; when the mass concentration is reduced to 1 mg / L, the lethality rates of Ⅰd and Ⅰf still reach more than 80% (specific activities are shown in Table 1), and excellent effects on the prevention and control of agricultural and forestry pests can be achieved. The compounds of the present invention are fluorine-containing nitrogen heterocyclic ester compounds, having the characteristics of high biological activity, low toxicity to beneficial organisms, easy degradation, and good environmental compatibility, and are particularly suitable for the control of drug-resistant agricultural pests that are currently widespread, and have good development and application prospects as new varieties of insecticidal pesticides.

[0016] The compounds of the present invention are used for preventing and controlling agricultural and forestry pests, and can be used alone or in combination with other active substances to improve the comprehensive performance of the product.

[0017] The present invention also includes an insecticidal composition with the compound of General Formula Ⅰ as the active ingredient, wherein the active ingredient accounts for 1-99% by weight of the composition. The insecticidal composition also includes an agriculturally or forestry-acceptable carrier.

[0018] It should be clear that various changes or modifications can be made within the scope defined by the claims of the present invention. Detailed Embodiments

[0019] The following synthesis examples and bioassay test results can be used to further illustrate the present invention, but do not mean to limit the present invention.

[0020] Synthesis Examples

[0021] Example 1. Preparation of Compound Ⅰa:

[0022] (1) Synthesis of Intermediate A [2,6-difluorothiobenzamide]

[0023]

[0024] In a 250 mL single-necked flask, first add 15.8 g (0.1 mol) of 2,6-difluorobenzoic acid, then add 80 mL of toluene as the reaction solvent, and then add 13.6 g (0.115 mol) of thionyl chloride. Add a reflux condenser, stir, and heat the reaction to reflux. Under the reflux condition, react for 4 h. Monitor the reaction progress by TLC. After the reaction is complete, distill off the excess solvent and thionyl chloride under reduced pressure to obtain 17.25 g of intermediate 2,6-difluorobenzoyl chloride, which is a light yellow oily liquid with a yield of 98%.

[0025] In a 250 mL three-necked flask, first add 100 mL of ammonia water, then place the reaction flask in a cold trap, control the temperature of the cold trap at 0 °C, stir, and slowly add a solution of 17.6 g (0.1 mol) of 2,6-difluorobenzoyl chloride in acetonitrile (concentration 40%) dropwise to the reaction solution within 1 h. After the addition is complete, transfer the reaction flask to room temperature and continue the reaction for 2 h. Monitor the reaction progress by TLC. After the reaction is complete, filter the reaction solution by suction, collect the filter cake, and dry it to obtain 15.2 g of white solid 2,6-difluorobenzamide with a yield of 96.8%.

[0026] In a 250 mL three-necked flask, first add 15.7 g (0.1 mol) of 2,6-difluorobenzamide, then add 60 mL of absolute ethanol as the reaction solvent, and finally add 8.88 g (0.04 mol) of phosphorus pentasulfide. Stir and slowly raise the reaction temperature to 50 °C, and maintain the temperature for the reaction for 12 h. Monitor the reaction progress by TLC. After the reaction is complete, cool down, distill off the excess ethanol under reduced pressure, then add 60 mL of water, and extract it in three batches (3 × 20 mL) with 60 mL of ethyl acetate. Combine the organic phases, dry them with anhydrous sodium sulfate, and distill under reduced pressure to obtain 14.7 g of red solid intermediate 2,6-difluorothiobenzamide with a yield of 85%.

[0027] (2) Synthesis of intermediate B [diethyl bromomalonate]

[0028]

[0029] In a 250 mL three-necked flask, add 16 g (0.1 mol) of diethyl malonate, then add 80 mL of chloroform as the solvent, and add two drops of concentrated sulfuric acid as the catalyst. Stir, and add 17.8 g (0.1 mol) of N-bromosuccinimide in batches within 1 h at room temperature. After the addition is complete, raise the temperature to 50 °C and continue the reaction for 12 h. Monitor the reaction by TLC until it is complete. Cool down, wash the reaction solution three times (3 × 50 mL) with 150 mL of saturated sodium chloride aqueous solution, collect the organic phase, dry it with anhydrous sodium sulfate, and distill off the excess solvent under reduced pressure to obtain 23.1 g of intermediate B, which is a transparent liquid with a yield of 97%.

[0030] (3) Synthesis of Intermediate C [Ethyl 2-(2,6-difluorophenyl)-4-hydroxythiazole-5-carboxylate]

[0031]

[0032] In a 250 mL three-necked flask, 17.3 g (0.1 mol) of Intermediate A1 was added, then 50 mL of anhydrous ethanol was added as a solvent, and finally 27.4 g (0.115 mol) of Intermediate B was added. The mixture was stirred and gradually heated to reflux for 8 h. The reaction was monitored by TLC until completion. After cooling, most of the ethanol in the reaction solution was removed by distillation under reduced pressure. At this time, a solid precipitated in the reaction solution. The solid was filtered by suction, washed with a small amount of anhydrous ethanol, and the filter cake was collected and dried to obtain 21.3 g of Intermediate C, a white solid, with a yield of 74.7%.

[0033] (4) Synthesis of Compound Ia

[0034]

[0035] In a 100 mL three-necked flask, 2.85 g (0.01 mol) of Intermediate C was first added, then 20 mL of acetonitrile was added as a solvent, and 1.2 g of triethylamine was added as an acid-binding agent. 2.18 g (0.0105 mol) of o-(trifluoromethyl)benzoyl chloride was slowly added dropwise within 10 min. After the addition was complete, the reaction was carried out at room temperature for 2 - 4 h. The reaction process was monitored by TLC. After the reaction was completed, 30 mL of water was added to the reaction solution, and the mixture was extracted with ethyl acetate (3×30 mL). The organic phase was washed with saturated brine, dried over anhydrous sodium sulfate, and the ethyl acetate was removed by distillation under reduced pressure to obtain a crude product. The crude product was separated by column chromatography (V(ethyl acetate):V(petroleum ether) = 1:15) to obtain the target compound Ia.

[0036] The synthesis methods of other compounds Ib - Ih are similar to that of Ia.

[0037] The NMR data of the compounds in general formula I of the present invention are as follows:

[0038] Compound Ia: 1 H NMR(500MHz,DMSO-d 6 )δ8.34(d,J=6.9Hz,1H,Ar-H),8.06(d,J=7.4Hz,1H,Ar-H),7.85–7.70(m,3H,Ar-H),7.40(t,J=8.5Hz,2H,Ar-H),4.31(q,J=7.1Hz,2H,CH 2 ),1.22(t,J=6.9Hz,3H,CH 3 )。 13 C NMR(126MHz,DMSO-d6 ) δ (ppm): 167.76, 162.11, 160.56, 159.03, 158.48, 156.12, 154.99, 133.70, 133.08, 131.52, 129.63, 127.90, 127.33, 121.99, 114.52, 112.98, 112.78, 109.61, 61.92, 13.79.

[0039] Compound Ⅰb: 1 H NMR (500 MHz, DMSO-d 6 ) δ 8.19 (d, J = 7.9 Hz, 1H, Ar-H), 7.77–7.63 (m, 2H, Ar-H), 7.49 (d, J = 7.8 Hz, 2H, Ar-H), 7.41 (t, J = 9.3 Hz, 2H, Ar-H), 4.26 (q, J = 7.0 Hz, 2H, CH 2 ), 2.62 (s, 3H, CH 3 ), 1.16 (t, J = 7.0 Hz, 3H, CH 3 ). 13 C NMR (126 MHz, DMSO-d 6 ) δ (ppm): 161.72, 158.65, 157.29, 156.65, 153.99, 139.08, 131.93, 131.90, 130.16, 129.35, 124.61, 124.52, 123.88, 112.44, 111.18, 110.96, 107.80, 59.88, 19.21, 11.88.

[0040] Compound Ⅰc: 1 H NMR (500 MHz, DMSO-d 6 ) δ 8.49 (d, J = 7.8 Hz, 1H, Ar-H), 8.42 (s, 1H, Ar-H), 8.22 (d, J = 7.9 Hz, 1H, Ar-H), 7.94 (t, J = 7.8 Hz, 1H, Ar-H), 7.78–7.67 (m, 1H, Ar-H), 7.40 (t, J = 9.4 Hz, 2H, Ar-H), 4.23 (q, J = 7.0 Hz, 2H, CH 2 ), 1.11 (t, J = 7.0 Hz, 3H, CH 3 ). 13 C NMR (101 MHz, DMSO-d 6) δ (ppm): 166.47, 162.69, 161.34, 159.53, 156.63, 155.79, 134.63, 133.70, 132.38, 131.33, 130.58, 129.11, 126.85, 125.95, 122.38, 113.60, 113.35, 62.36, 14.20。

[0041] Compound Ⅰd: 1 H NMR (400 MHz, DMSO-d 6 ) δ (ppm): 8.15 (s, 3H, Ar-H), 7.78–7.66 (m, 1H, Ar-H), 7.40 (t, J = 9.3 Hz, 2H, Ar-H), 4.24 (q, J = 7.1 Hz, 2H, CH 2 ), 1.14 (t, J = 7.1 Hz, 3H, CH 3 )。 13 C NMR (101 MHz, DMSO-d 6 ) δ (ppm): 172.39, 165.46, 165.41, 161.69, 159.50, 158.79, 135.59, 134.98, 133.64, 132.73, 131.28, 129.08, 128.26, 113.63, 113.47, 113.22, 60.97, 14.76。

[0042] Compound Ⅰe: 1 H NMR (400 MHz, DMSO-d 6 ) δ 7.86 (tt, J = 8.5, 6.3 Hz, 1H, Ar-H), 7.72 (tt, J = 8.5, 6.3 Hz, 1H, Ar-H), 7.40 (td, J = 8.9, 2.0 Hz, 4H, Ar-H), 4.29 (q, J = 7.1 Hz, 2H, CH 2 ), 1.22 (t, J = 7.1 Hz, 4H, CH 3 )。 13 C NMR (101 MHz, DMSO-d 6 ) δ (ppm): 162.67, 162.57, 161.26, 160.00, 159.39, 158.77, 158.24, 156.71, 154.79, 136.99, 134.28, 115.07, 113.78, 113.59, 113.53, 113.34, 110.12, 107.84, 62.45, 14.25。

[0043] Compound Ⅰf:1 H NMR (500 MHz, DMSO-d 6 ) δ (ppm): 8.70 (s, 2H, Ar-H), 8.62 (s, 1H, Ar-H), 7.75–7.66 (m, 1H, Ar-H), 7.37 (t, J = 9.3 Hz, 2H, Ar-H), 4.21 (q, J = 7.1 Hz, 2H, CH 2 ), 1.11 (t, J = 7.0 Hz, 3H, CH 3 ). 13 C NMR (126 MHz, DMSO-d 6 ) δ (ppm): 166.81, 163.04, 162.72, 161.08, 160.73, 158.34, 157.09, 135.90, 133.73, 132.50, 132.42, 131.57, 130.24, 125.87, 123.70, 116.32, 115.10, 114.92, 111.69, 63.95, 15.70.

[0044] Compound Ig: 1 H NMR (400 MHz, DMSO-d 6 ) δ (ppm): 8.11 (d, J = 8.4 Hz, 2H, Ar-H), 7.75–7.65 (m, 3H, Ar-H), 7.39 (t, J = 9.3 Hz, 2H, Ar-H), 4.22 (q, J = 7.1 Hz, 2H, CH 2 ), 1.35 (s, 9H, CH 3 ), 1.12 (t, J = 7.1 Hz, 3H, CH 3 ). 13 C NMR (101 MHz, DMSO-d 6 ) δ (ppm): 167.72, 163.72, 161.34, 159.58, 158.57, 156.49, 134.43, 130.61, 129.66, 126.56, 125.84, 125.28, 113.60, 113.38, 107.90, 62.23, 35.57, 31.23, 14.25.

[0045] Compound Ih: 1 H NMR (500 MHz, DMSO-d 6)δ8.19(d,J=7.5Hz,2H,Ar-H),7.83(t,J=7.4Hz,1H,Ar-H),7.74–7.63(m,3H,Ar-H),7.38(d,J=9.2Hz,2H,Ar-H),4.22(q,J=7.3Hz,2H,CH 2 ),1.11(t,J=7.2Hz,3H,CH 3 ). 13 C NMR (126 MHz, DMSO-d 6 )δ(ppm): 165.51,162.74,161.25,160.73,158.12,157.96,136.94,135.9 1,132.29,131.33,129.71,116.60,115.19,115.01,111.87,63.91,15.88.

[0046] Biological activity test

[0047] Example 2: Insecticidal activity assay

[0048] (1) Method for determining the activity against Plutella xylostella

[0049] The target compound synthesized was tested for biological activity according to Part 14: Leaf Dipping Method of NY / T 1154.14-2008 "Guidelines for Indoor Bioassay of Pesticides". The specific method is as follows: According to the experimental design, the agent was prepared into a series of dilutions, with 0.1% Tween-80 water as the control; fresh cabbage leaves were selected, cut into 3 cm square pieces, immersed in the corresponding agent for 10 seconds, and then taken out and dried naturally. 9 cm diameter filter paper was spread on the bottom of a 9 cm diameter culture dish, and the 3rd instar larvae of diamondback moth of the same size were placed. After starvation treatment for 2 hours, the poisoned leaves were placed; each treatment was repeated 3 times, placed under (26±1)℃, light 16h:8h (L:D) conditions, and after 24h, 48h, and 72h of treatment, the insects that could not move when touched by a brush were considered dead, and the number of dead insects was recorded, and the mortality rate and corrected mortality rate of each treatment were calculated.

[0050] Mortality rate (%) = number of dead insects / total number of insects treated × 100

[0051] Corrected mortality rate (%) = (treatment mortality rate - control mortality rate) / (100 - control mortality rate) × 100

[0052] Table 2 Test results of the activity of the compounds of general formula I against Plutella xylostella

[0053]

[0054] The test results show that the compound of the present invention has good killing activity against Plutella xylostella. When the mass concentration is 100 mg / L, the lethality rate of Plutella xylostella at 1 h is 93%, and the rest all reach 100%; when the mass concentration is 10 mg / L, the lethality rates of Ia, Id, and If reach 100%, the lethality rate of Ic reaches 95%, and the lethality rate of Ie reaches 89%; when the mass concentration is reduced to 1 mg / L, the lethality rates of Id and If still reach 85% and 83% respectively.

Claims

1. A fluorobenzene benzothiazole diester compound has a structure shown in general formula I: where R 1 is: H, F, CH 3 , CF 3 ; R 2 is: H, Cl, CF 3 ; R 3 is: H, C(CH 3 ) 3 ; R 4 is: H, Cl, CF 3 ; R 5 is: H, F.

2. Use of the fluorobenzene benzothiazole diester compound according to claim 1, characterized in that the compound of general formula I is used as an agricultural or forestry insecticide and has a control effect on agricultural pests.

3. An insecticide composition contains the compound of general formula I according to claim 1 as an active ingredient and an agriculturally or forestry-acceptable carrier.

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