Preparation method of jasmonic acid methyl ester and application of jasmonic acid methyl ester in fertilizer

Abstract

The invention relates to a preparation method of methyl jasmonate, (E)-4-oxodec-7-olefine aldehyde is used as a raw material, in the presence of an ionic liquid, the methyl jasmonate is prepared through a ring closing reaction, an addition reaction and a deacidification reaction, and complex post-treatment is not needed in the reaction process. The preparation method is simple in process steps, the ionic liquid can catalyze the reaction at the same time, the reaction yield and the product purity are improved, the reaction time is shortened, the reaction condition is mild, the reaction can be carried out only at room temperature, and the method is more suitable for industrialization. In addition, the methyl jasmonate prepared by the method is high in purity, can be directly used as a fertilizer additive, and does not need further purification treatment.

Description

Technical Field

[0001] The present invention relates to the field of organic synthesis, and in particular to a preparation method of methyl jasmonate and application of the same in fertilizers. Background Art

[0002] Methyl jasmonate (MeJA), an important plant signaling molecule and biostimulant, possesses numerous potential applications and synergistic effects. Methyl jasmonate can enhance plant stress tolerance by providing a "warning signal" and activating defense systems (such as the production of antioxidant enzymes, osmotic regulators, and secondary metabolites). This allows plants to better survive and maintain growth in the face of abiotic and biotic stresses, such as drought, salinity, high and low temperatures, heavy metal pollution, pests and diseases. Furthermore, by improving plant survival and health under adverse conditions, methyl jasmonate can indirectly help plants more efficiently utilize nutrients from soil and fertilizers, thereby maintaining or even increasing yields under adverse conditions. Under normal conditions, moderate concentrations of MeJA can sometimes positively impact the growth of specific crops by regulating the expression of growth-related genes (although high concentrations can inhibit growth). Some studies have shown that MeJA treatment can influence root development (such as increasing lateral roots) or modulate the expression of nutrient transporters, thereby improving plant uptake of key nutrients such as nitrogen, phosphorus, and potassium. Therefore, methyl jasmonate can be added to fertilizer formulations designed to target specific stresses (such as drought- and salt-tolerant fertilizers) or to improve quality (such as high-quality fruit fertilizers). It can be used in conjunction with conventional fertilizers (e.g., foliar sprays or root irrigation) during anticipated stress (such as drought forecasts) or during critical periods of quality development to enhance the fertilizer's effectiveness under adverse conditions or specifically improve quality. Methyl jasmonate is typically used as an additive to foliar sprays (the most common), root irrigation (drip irrigation, root irrigation), or seed treatments. It can also be incorporated into solid fertilizers as a slow-release formulation or coating.

[0003] Therefore, integrating methyl jasmonate into fertilizer products or using it in conjunction with fertilizers as a fertilizer synergist, stress-resistant additive, or quality enhancer is its most promising application in the fertilizer field. It can help achieve the modern agricultural goals of "reducing fertilizer use and increasing efficiency," enhancing crop stress resistance, and improving agricultural product quality. Although large-scale commercial application is still under development, it has enormous potential in precision agriculture and green farming.

[0004] So far, the methods for synthesizing methyl jasmonate at home and abroad are as follows: 1. Adipic acid synthesis route In 1987, Hideaki Kataoka et al. reported a synthetic route for preparing methyl jasmonate using adipic acid ester as the starting material with a total yield of 60% through six steps.

[0005]

[0006] The key step of this synthetic route is the decarbonylation reaction to conjugated cyclopentenone under the catalysis of palladium acetate.

[0007] 2. Cyclopentenol route The route starts from cyclopentenol and passes through VB 12 Methyl jasmonate can be obtained through four steps of reaction with an overall yield of 20%.

[0008]

[0009] 3. Cis-4-heptenoic acid route This route starts from 4-heptenoic acid and produces methyl jasmonate through 7 steps with an overall yield of 23.8%.

[0010]

[0011]

[0012] Existing methods have problems such as long reaction routes, low yields, and low product purity. Therefore, developing a method for preparing methyl jasmonate with mild reaction conditions, simple steps, high yield, and easy purification has important economic and social value. Summary of the Invention

[0013] The present invention aims to provide a method for preparing methyl jasmonate, so as to solve the technical problems existing in the prior art such as long reaction time, low yield, low purity, and environmental pollution.

[0014] In order to solve the above technical problems, the present invention provides the following technical solutions: A preparation method of methyl jasmonate, characterized in that the reaction formula of the preparation method is: ; The process comprises the following reaction steps: 1) In the presence of an ionic liquid, a cyclization reaction is performed on (E)-4-oxodecan-7-enal of Formula 1 to obtain intermediate 2; 2) Intermediate 2 is subjected to an addition reaction with dimethyl malonate, followed by a decarboxylation reaction to obtain methyl jasmonate; wherein the ionic liquid is selected from .

[0015] Furthermore, the reaction temperature of step 1) is 110° C. to 130° C., and the reaction time is 0.5 to 2 hours.

[0016] Furthermore, in step 1), the mass volume ratio of (E)-4-oxodecan-7-enal to the ionic liquid is 1:3-20, expressed in g / mL, more preferably 1:5-10.

[0017] Furthermore, the molar ratio of dimethyl malonate in step 2) to (E)-4-oxodecan-7-enal in step 1) is 1.0-2.0:1, preferably 1.0-1.5:1, and most preferably 1.2:1.

[0018] Furthermore, in step 2), the addition reaction is carried out at a temperature between -5°C and 5°C, and the reaction time is 5 to 7 hours.

[0019] Furthermore, adipic acid is added to the decarboxylation reaction in step 2).

[0020] Furthermore, the decarboxylation reaction temperature in step 2) is 180-210°C.

[0021] Furthermore, the decarboxylation reaction time in step 2) is 5 to 7 hours.

[0022] Furthermore, the preparation method of the present invention comprises the following steps: 1) Add (E)-4-oxodecan-7-enal and ionic liquid shown in formula 1 to the reactor , heat to 110℃~130℃, react for 0.5~2 hours, after the reaction is complete, cool the reaction solution to room temperature and use it directly in the next reaction without post-treatment; 2) Add 31.7 g of methyl malonate to the reaction solution of step 1), stir at -5-5°C for 5-7 minutes, then add water, raise the temperature to 50-60°C and react for 1-3 hours, then adjust the pH to 2-4, extract three times with chloroform, combine the chloroform layers, dry over anhydrous magnesium sulfate, remove chloroform, and then distill under reduced pressure to remove excess dimethyl malonate. The product is directly subjected to the next reaction; Adipic acid was added to the above product, heated to 180-210°C, reacted for 5-7 hours, cooled to room temperature, added with chloroform, washed with saturated sodium bicarbonate solution and saturated sodium chloride solution, dried over anhydrous magnesium sulfate, the solvent was removed, and purified by column chromatography to obtain the product methyl jasmonate.

[0023] Furthermore, the present invention also provides the use of methyl jasmonate as a fertilizer additive.

[0024] Furthermore, the methyl jasmonate prepared by the method of the present invention has high purity and can be directly used as a fertilizer additive without further purification treatment.

[0025] In recent years, the unique solvent properties of ionic liquids have led to their widespread application in synthesis and catalysis. Based on this, and after extensive research, the present inventors have discovered that the reactions of steps 1) and 2) can be carried out under relatively mild conditions in the presence of the functionalized ionic liquids of the present invention, with high product yields and purity. The ionic liquids of the present invention act as both solvents and catalysts, ensuring smooth reaction progress while reducing reaction byproducts and improving product purity. Furthermore, the addition of additional solvents during the reaction process is unnecessary, saving costs and reducing wastewater generation during post-processing, thus meeting environmental protection requirements.

[0026] The beneficial effects of the present invention are: 1) The present invention provides a method for preparing methyl jasmonate, which uses (E)-4-oxodecan-7-enal as a raw material and undergoes a ring-closure reaction, an addition reaction, and a deacidification reaction in the presence of an ionic liquid to obtain methyl jasmonate. The reaction process does not require complicated post-treatment, can save operating costs and labor costs, and is more suitable for industrialization.

[0027] 2) The preparation method of the present invention has simple process steps, and the ionic liquid can catalyze the above reactions simultaneously, thereby improving the reaction yield and product purity, reducing the reaction time, and the reaction conditions are mild and can be carried out at room temperature.

[0028] 3) The ionic liquid of the present invention is easy to separate and can be reused after simple activation. At the same time, no additional solvent needs to be added during the reaction process, which saves production costs, meets the requirements of green environmental protection, and is conducive to industrial production.

[0029] 4) The methyl jasmonate prepared by the method of the present invention has high purity and can be directly used as a fertilizer additive without further purification. DETAILED DESCRIPTION

[0030] The following will clearly and completely describe the technical solutions of the present invention in conjunction with the embodiments. Obviously, the embodiments described are only some embodiments of the present invention, not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making creative efforts are within the scope of protection of the present invention.

[0031] The present invention will be further explained below with reference to specific embodiments.

[0032] Example 1: Preparation of ionic liquid The ionic liquid was prepared according to the method in the literature (Study on the catalytic synthesis of sec-butanol by choline-based alkaline ionic liquid, Chen Jie et al., Journal of Chemical Industry and Engineering, 2023, 74(9): 3716-3730). The specific steps are as follows: .

[0033] Choline chloride (1 mol, 139 g) was dissolved in methanol (500 ml), and sodium methoxide (1 mol, 54 g) was added and dissolved under vigorous stirring. The mixture was heated to 60°C and reacted for 24 h. After cooling to room temperature, the precipitate was filtered and the filtrate was rotary evaporated to remove the solvent to obtain the alkaline ionic liquid catalyst. .

[0034] Example 2

[0035] 1) Add 33.6 g (0.2 mol) of (E)-4-oxodecan-7-enal (Formula 1) and 200 mL of ionic liquid to a reaction kettle equipped with a thermometer, magnetic stirring, and condenser. After stirring, heat to 120°C and react for 1 hour. GC was used to monitor the reaction progress. After the reaction was complete, the reaction solution was cooled to room temperature and used directly in the next reaction without post-treatment.

[0036] 2) Add 31.7 g (0.24 mol) of methyl malonate to the reaction mixture from step 1) and stir in an ice bath (0-5°C) for 6 h. Then, add 50 ml of water and heat to 50°C for 2 h. Then, add 10% dilute hydrochloric acid to adjust the pH to approximately 3. Extract three times with chloroform. Combine the chloroform layers and dry over anhydrous magnesium sulfate. After removing the chloroform, remove the excess dimethyl malonate by vacuum distillation. The product is then directly subjected to the next reaction.

[0037] To the above product, 25 g of adipic acid was added, heated to 190°C, reacted for 6 hours, cooled to room temperature, and 250 mL of chloroform was added. The mixture was washed three times with saturated sodium bicarbonate solution and three times with saturated sodium chloride solution, and dried over anhydrous magnesium sulfate. The solvent was removed and the mixture was purified by column chromatography to obtain 39.5 g of methyl jasmonate, with a yield of 88.2% and a purity of 99.5%.

[0038] Example 3 1) Add 33.6 g (0.2 mol) of (E)-4-oxodecan-7-enal (Formula 1) and 200 mL of ionic liquid to a reaction kettle equipped with a thermometer, magnetic stirring, and condenser. After stirring, the mixture was heated to 110°C and allowed to react for 2 hours. GC was used to monitor the reaction progress. After the reaction was complete, the reaction solution was cooled to room temperature and used directly in the next step without post-treatment.

[0039] 2) Add 40.0 g (0.30 mol) of methyl malonate to the reaction mixture from step 1) and stir in an ice bath (0-5°C) for 6 h. Then, add 50 ml of water and heat to 50°C for 2 h. Then, add 10% dilute hydrochloric acid to adjust the pH to approximately 3. Extract three times with chloroform. Combine the chloroform layers and dry over anhydrous magnesium sulfate. After removing the chloroform, remove the excess dimethyl malonate by vacuum distillation. The product is then directly subjected to the next reaction.

[0040] To the above product, 20 g of adipic acid was added, heated to 200°C, reacted for 5 hours, cooled to room temperature, and 250 mL of chloroform was added. The mixture was washed three times with saturated sodium bicarbonate solution and three times with saturated sodium chloride solution, and dried over anhydrous magnesium sulfate. The solvent was removed, and the mixture was purified by column chromatography to obtain 38.4 g of methyl jasmonate, with a yield of 85.7% and a purity of 99.6%.

[0041] Example 4 1) Add 33.6 g (0.2 mol) of (E)-4-oxodecan-7-enal (Formula 1) and 250 mL of ionic liquid to a reaction kettle equipped with a thermometer, magnetic stirring, and condenser. After stirring, heat to 130°C and react for 1 hour. GC was used to monitor the reaction progress. After the reaction was complete, the reaction solution was cooled to room temperature and used directly in the next reaction without post-treatment.

[0042] 2) Add 31.7 g (0.24 mol) of methyl malonate to the reaction mixture from step 1) and stir in an ice bath (0-5°C) for 6 h. Then, add 50 ml of water and heat to 50°C for 2 h. Then, add 10% dilute hydrochloric acid to adjust the pH to approximately 3. Extract three times with chloroform. Combine the chloroform layers and dry over anhydrous magnesium sulfate. After removing the chloroform, remove the excess dimethyl malonate by vacuum distillation. The product is then directly subjected to the next reaction.

[0043] To the above product, 30 g of adipic acid was added, heated to 200°C, reacted for 5 hours, cooled to room temperature, and 250 mL of chloroform was added. The mixture was washed three times with saturated sodium bicarbonate solution and three times with saturated sodium chloride solution, and dried over anhydrous magnesium sulfate. The solvent was removed and the mixture was purified by column chromatography to obtain 37.7 g of methyl jasmonate, with a yield of 84.2% and a purity of 99.5%.

[0044] The above embodiments are preferred implementation modes of the present invention, but the implementation modes of the present invention are not limited to the above embodiments. Any other changes, modifications, substitutions, combinations, and simplifications that do not deviate from the spirit and principles of the present invention should be considered as equivalent replacement methods and are included in the scope of protection of the present invention.

Claims

1. A method for preparing methyl jasmonate, characterized in that: The reaction formula of the preparation method is: ； The process comprises the following reaction steps: 1) In the presence of an ionic liquid, a cyclization reaction is performed on (E)-4-oxodecan-7-enal of Formula 1 to obtain intermediate 2; 2) Intermediate 2 is subjected to an addition reaction with dimethyl malonate, followed by a decarboxylation reaction to obtain methyl jasmonate; wherein the ionic liquid is selected from .

2. The method for preparing methyl jasmonate according to claim 1, characterized in that the reaction temperature in step 1) is 110°C to 130°C, and the reaction time is 0.5 to 2 hours.

3. The method for preparing methyl jasmonate according to claim 1, wherein the mass volume ratio of (E)-4-oxodecan-7-enal to the ionic liquid in step 1) is 1:3 to 20, and the unit is g / mL.

4. The method for preparing methyl jasmonate according to claim 1, wherein the molar ratio of dimethyl malonate in step 2) to (E)-4-oxodecan-7-enal in step 1) is 1.0-2.0:

1.

5. The method for preparing methyl jasmonate according to claim 1, characterized in that the addition reaction in step 2) is carried out at a temperature of -5°C to 5°C and a reaction time of 5 to 7 hours.

6. The method for preparing methyl jasmonate according to claim 1, wherein: Adipic acid is also added to the decarboxylation reaction in step 2).

7. The method for preparing methyl jasmonate according to claim 1, characterized in that the decarboxylation reaction temperature in step 2) is 180-210°C and the decarboxylation reaction time is 5-7 hours.

8. The method for preparing methyl jasmonate according to claim 1, characterized in that it comprises the following steps: 1) Add (E)-4-oxodecan-7-enal and ionic liquid shown in formula 1 to the reactor , heat to 110℃~130℃, react for 0.5~2 hours, after the reaction is complete, cool the reaction solution to room temperature and use it directly in the next reaction without post-treatment; 2) Add 31.7 g of methyl malonate to the reaction solution of step 1), stir at -5-5°C for 5-7 minutes, then add water, raise the temperature to 50-60°C and react for 1-3 hours, then adjust the pH to 2-4, extract three times with chloroform, combine the chloroform layers, dry over anhydrous magnesium sulfate, remove chloroform, and then distill under reduced pressure to remove excess dimethyl malonate. The product is directly subjected to the next reaction; Adipic acid was added to the above product, heated to 180-210°C, reacted for 5-7 hours, cooled to room temperature, added with chloroform, washed with saturated sodium bicarbonate solution and saturated sodium chloride solution, dried over anhydrous magnesium sulfate, the solvent was removed, and purified by column chromatography to obtain the product methyl jasmonate.

9. A use of methyl jasmonate as a fertilizer additive, characterized in that The methyl jasmonate is prepared according to the method according to any one of claims 1 to 9.

Images