Diene derivative as well as preparation method and application thereof

Abstract

The invention relates to the technical field of dyes, and particularly discloses a diene derivative as well as a preparation method and application thereof. By controlling the reaction conditions, the diene derivatives can be stably obtained, and the diene derivatives have great potential in the development of organic dyes or drugs. The preparation method provided by the invention has the advantages of good stability and good repeatability, and is suitable for preparation to obtain the required diene derivative.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of dyes, in particular to a diene derivative and a preparation method and application thereof. BACKGROUND

[0002] Yellow dyes are an important variety of dyes. Bio-based yellow pigments are particularly attractive. However, most bio-based yellow pigments have poor color performance, insufficient color and stability, and it is difficult to achieve bright and pure yellow. In addition, yellow plant dyes have poor color fastness and are prone to fading, and some dye solutions are acidic, which accelerates the acidification and aging of fabrics. Some dyes have insufficient affinity for specific materials (such as cotton fibers) and need to be modified to improve the utilization rate.

[0003] Indigoidine, also known as indigoidine, is a substance with a bicyclic structure formed by the condensation of two glutamine molecules under the action of indigoidine synthetase. Indigoidine is a stable and bright natural blue pigment with many excellent properties. Its application fields are wide, including cosmetics, fabric printing and dyeing, and pharmaceutical industry. The pyridone compounds described in the article Bioorg Med Chem Lett. 2021, 38, 127849 have many applications in medicine. Such as the pyridone structure of the new drug for lung disease developed by Roche, Esbriet, and the CDK4 / 6 inhibitor Palbociclib developed by Pfizer.

[0004] However, when indigoidine is used as a raw material, it is difficult to control the product singularity when synthesizing such derivatives, and how to accurately control the derivation path still has technical challenges. SUMMARY

[0005] The present application aims to overcome the shortcomings of the prior art and provide a diene derivative and a preparation method and application thereof.

[0006] To achieve the above-mentioned purpose, the technical scheme adopted by the present application is as follows: The present application provides a diene derivative, the structural formula of the diene derivative is shown as formula I; Formula I; Wherein, Ra, Rb is one of -OH, -NH2; Rc is one of -OH, -COOH; Rd is one of the following three structures:

[0007] As a preferred embodiment of the diene derivative described in the present application, the diene derivative includes any one of the following structures:

[0008] The diene derivative with the above structural formula has the advantages of easy preparation, high natural degree and good stability, and has great potential in the development of organic dyes.

[0009] The application also provides a preparation method of the diene derivative, comprising the following steps: The substrate is added into the alkaline water, and a heating reflux reaction is performed to obtain a reaction liquid, then the pH of the reaction liquid is adjusted to 2-6 by using an acid, and then solid-liquid separation is performed, and the precipitate is obtained after separation, and purification is performed to obtain the diene derivative.

[0010] The application adopts the above technical solution, controls the above reaction conditions, and has good stability and good repeatability in the preparation process, so that the diene derivative with the above structure can be accurately obtained.

[0011] In the application, the indigo blue is a natural blue pigment obtained by microbial fermentation, which is a lactam structural compound and belongs to pyridine heterocyclic reductive dyes. The dye produces various downstream products in the application process. Indigo blue will undergo hydrolytic ring opening under alkaline conditions to generate amides and carboxylic acids and other substances. When the above control reaction conditions are adopted, the yield of the hydrolytic ring opening product is significantly increased, and the content of other by-products is effectively reduced, thereby obtaining the diene derivative with the above structural formula.

[0012] As a preferred embodiment of the preparation method of the diene derivative described in the application, the alkaline water is at least one of sodium hydroxide, potassium hydroxide and potassium tert-butoxide.

[0013] In the technical solution of the application, indigo blue can quickly and efficiently undergo hydrolytic ring opening in the above type of alkaline water to generate amides and carboxylic acids and other substances.

[0014] As a preferred embodiment of the preparation method of the diene derivative described in the application, the acid is at least one of sulfuric acid, hydrochloric acid, acetic acid and citric acid.

[0015] The application has the advantages of high economy and small amount of the above type of acid used for adjusting the pH.

[0016] As a preferred embodiment of the preparation method of the diene derivative described in the application, the pH of the reaction liquid is adjusted to 3-4 by using an acid.

[0017] The pH of the reaction liquid is adjusted to 3-4 by using an acid, and the separation degree of the solid-liquid separation is better.

[0018] As a preferred embodiment of the preparation method of the diene derivative described in the application, the molar ratio of the indigo blue to the alkaline water is 1: (1-10).

[0019] This application uses the above molar ratio of lanthanum and alkaline water to better hydrolyze lanthanum and better generate diene derivatives with the above structure.

[0020] In a preferred embodiment of the preparation method of the diene derivative described in this application, the mass ratio of the blue pigment to the alkaline water is 1:(2~50). At this ratio, the target product can be obtained efficiently while avoiding excessive water volume that would lead to increased wastewater.

[0021] As a preferred embodiment of the preparation method of the diene derivatives described in this application, the conditions for the heating reflux reaction include: Add the substrate Visible Blue to alkaline water and heat under reflux at 60-80°C for 8-14 hours. Then cool to 5-10°C to obtain the reaction solution. Under reflux conditions, the reaction is more complete and rapid, avoiding the formation of more other byproducts.

[0022] In a preferred embodiment of the preparation method of the diene derivatives described in this application, the solid-liquid separation is performed using a solid-liquid separation instrument, which includes any one of a horizontal screw centrifuge, a flat plate centrifuge, or a plate and frame filter press.

[0023] In some specific embodiments, the preparation method of the diene derivative with the structural formula shown in (a) includes the following steps: 1) Mix sodium hydroxide and water, add blue pigment, heat to 40°C and reflux for 4 hours, then cool to 5°C to obtain the reaction solution; 2) The pH of the reaction solution was adjusted to 3-4 with sulfuric acid, and then solid-liquid separation was performed. After separation, the precipitate was obtained, purified, and diene derivative a was obtained.

[0024] In some specific embodiments, the preparation method of the diene derivative with the structural formula shown in (b) includes the following steps: 1) Mix sodium hydroxide and water, add blue, heat to 40°C and reflux for 8 hours, then cool to 5°C to obtain the reaction solution; 2) The pH of the reaction solution was adjusted to 3-4 using sulfuric acid, and then solid-liquid separation was performed. After separation, the precipitate was obtained, purified, and diene derivative b was obtained.

[0025] In some specific embodiments, when the diene derivative has the structural formula shown in (c), the preparation method includes the following steps: 1) Mix sodium hydroxide and water, add blue, heat to 80℃ and reflux for 10 hours, then cool to 5℃ to obtain the reaction solution; 2) The pH of the reaction solution was adjusted to 3-4 with sulfuric acid, and then solid-liquid separation was performed. After separation, the precipitate was obtained, purified, and diene derivative c was obtained.

[0026] In some specific embodiments, the preparation method of the diene derivative with the structural formula shown in (d) includes the following steps: 1) Mix sodium hydroxide and water, add blue, heat to 60℃ and reflux for 10 hours, then cool to 5℃ to obtain the reaction solution; 2) The pH of the reaction solution was adjusted to 3-4 using sulfuric acid, and then solid-liquid separation was performed. After separation, the precipitate was obtained, purified, and diene derivative d was obtained.

[0027] This application also provides the application of the aforementioned diene derivatives in the synthesis of organic dyes.

[0028] The diene derivatives with the above structure can be better applied in the field of organic dyes.

[0029] Compared with the prior art, this application has the following beneficial effects: This application provides a diene derivative, its preparation method, and its applications. By controlling the reaction conditions, this application can stably obtain a class of diene derivatives, which have great potential in the development of organic dyes. The preparation method provided in this application has good stability and reproducibility, making it suitable for preparing desired diene derivatives. Attached Figure Description

[0030] Figure 1 MS spectrum of diene derivative a; Figure 2 MS spectrum of diene derivative b; Figure 3 MS spectrum of diene derivative c; Figure 4 The liquid phase diagram is for diene derivative d; Figure 5 The hydrogen spectrum of diene derivative d; Figure 6 The carbon spectrum of diene derivative d; Figure 7 The HSQC diagram for diene derivative d is shown. Figure 8 The HMBC diagram of diene derivative d; Figure 9 MS spectrum of diene derivative d; Figure 10 Powder and staining diagram of diene derivative d; Figure 11 The image shows the powder and staining of diene derivative b. Detailed Implementation

[0031] To better illustrate the purpose, technical solution, and advantages of this application, the following description will be provided in conjunction with the accompanying drawings and specific embodiments.

[0032] In the following examples and comparative examples, unless otherwise specified, the experimental methods used are conventional methods, and the materials and reagents used are commercially available unless otherwise specified. Furthermore, the raw materials used in each parallel experiment are the same.

[0033] The blue pigment used in the following examples was provided by Nanjing Hegu Life Biotechnology Co., Ltd. Product structure identification: The synthesized product was sent to the Analysis and Testing Center of Nanjing Normal University for testing.

[0034] In the following embodiments, the high-performance liquid chromatography (HPLC) method for detecting the product is described below.

[0035] Chromatographic conditions: Mobile phase: gradient elution of methanol and pure water, wavelength 400 nm, flow rate 1.0 mL / min, sample preparation solution: DMSO, injection volume: 10 μL, column temperature 35℃, run time 20 min. Column: Galasil EF-C18M 4.6 mmid × 250 mm L (SN B06211801).

[0036] Example 1, a diene derivative and a method for preparing the same This embodiment provides a method for preparing diene derivatives, including the following steps: (1) Weigh 1.48g of sodium hydroxide solid, place it in a 100mL reaction flask, add 40mL of water and stir, add 5g of blue, heat to 40℃ and react for 4h; (2) After the reaction is complete, the reaction system is cooled to 5°C and the pH is adjusted to 3 with 40% sulfuric acid. (3) Solid-liquid separation, collection of solid precipitate; (4) 1.4 g of diene derivative a was obtained by preparative chromatography separation and purification of the solid precipitate.

[0037] Separation conditions: Mobile phase: gradient elution of methanol and pure water, as shown in Table 1 below.

[0038] Table 1 Characterization data is: Formula:C 10 H8O7N2; ESI-MS: 268.0 [M].

[0039] The MS spectrum of diene derivative a is shown in [reference needed]. Figure 1 .

[0040] Example 2, a diene derivative and a method for preparing the same This embodiment provides a method for preparing diene derivatives, including the following steps: (1) Weigh 0.8g of potassium hydroxide solid, place it in a 100mL reaction flask, add 40mL of water and stir, add 5g of blue, heat to 40℃ and react for 8h; (2) After the reaction is complete, the reaction system is cooled to 5°C and the pH is adjusted to 4 with a 40% citric acid solution. (3) Solid-liquid separation, collection of solid precipitate; (4) 2.4g diene derivative b was obtained by preparative chromatography separation and purification of the solid precipitate.

[0041] Separation conditions: Mobile phase: gradient elution of methanol and pure water, as shown in Table 2 below.

[0042] Table 2 Characterization data is: Formula:C 10 H 12 O6N4; ESI-MS: 283.0 [MH] - The MS chromatogram of diene derivative b is shown in [reference needed]. Figure 2 .

[0043] Example 3, a diene derivative and a method for preparing the same This embodiment provides a method for preparing diene derivatives, including the following steps: (1) Weigh 2.80g of potassium tert-butoxide solid, place it in a 100mL reaction flask, add 40mL of water and stir to dissolve, add 5g of blue, heat to 80℃ and react for 10h.

[0044] (2) After the reaction is complete, the reaction system is cooled to 5°C and the pH is adjusted to 3 with sulfuric acid with a mass concentration of 40%.

[0045] (3) Solid-liquid separation, and collection of solid precipitate.

[0046] (4) 1.7g diene derivative c was obtained by preparative chromatography separation and purification of the solid precipitate.

[0047] Separation conditions: Mobile phase: gradient elution of methanol and pure water, as shown in Table 3 below.

[0048] Table 3 Characterization data is: Formula:C 10 H 10 O8N2; ESI-MS: 321.9 [M+K] + The mass spectrum of diene derivative C is shown below. Figure 3.

[0049] Example 4, a diene derivative and a method for preparing the same This embodiment provides a method for preparing diene derivatives, including the following steps: (1) Weigh 25.6g of sodium hydroxide solid, place it in a 500 mL reaction flask, add 400 mL of water and stir to dissolve it, add 20.0g of blue, heat to 60 ℃ and react for 10 h; (2) After the reaction is complete, the reaction system is cooled to 5°C and the pH is adjusted to 4 with 40% sulfuric acid. (3) Use a horizontal screw centrifuge to separate the solid and liquid components of the system and collect the solid precipitate; (4) The solid precipitate was purified by preparative chromatography to obtain 9g of diene derivative d.

[0050] Separation conditions: Mobile phase: gradient elution of methanol and pure water, as shown in Table 4 below.

[0051] Table 4 Characterization data are as follows: Formula: C9H8O6N2; ESI-MS: 241.1 [M+H] + ; 1 H NMR (400 MHz, DMSO-d6) δ 11.29 (s, 1H), 10.54 (s, 1H), 7.27 (s, 1H), 6.50 (s, 2H), 5.93 (s, 1H). 13 C NMR (101 MHz, DMSO) δ 163.29, 161.51, 160.35, 151.96, 139.99, 123.28, 115.46, 108.24, 82.13.

[0052] See attached NMR and mass spectrometry results. Figures 5 ~ 9 .in, Figure 5 The hydrogen spectrum of diene derivative d; Figure 6 The carbon spectrum of diene derivative d; Figure 7 The HSQC diagram for diene derivative d is shown. Figure 8 The HMBC diagram of diene derivative d; Figure 9 This is the MS spectrum of diene derivative d.

[0053] Example 5, a diene derivative and a method for preparing the same This embodiment provides a method for preparing diene derivatives, including the following steps: (1) Weigh 256.0g of sodium hydroxide solid, place it in a 5 L reaction flask, add 4L of water and stir to dissolve it, add 180g of blue, heat to 60℃ and react for 10 h; (2) After the reaction is complete, the reaction system is cooled to 5°C and the pH is adjusted to 4 with 40% sulfuric acid. (3) Use a horizontal screw centrifuge to separate the solid and liquid components of the system and collect the solid precipitate; (4) 105g diene derivative d was obtained by preparative chromatography separation and purification of the solid precipitate.

[0054] Separation conditions: Mobile phase: gradient elution of methanol and pure water, as shown in Table 5 below.

[0055] Table 5 Example 6, a diene derivative and a method for preparing the same Compared with Example 4, the difference in Example 6 is that in step (1), sodium hydroxide is replaced with potassium hydroxide, and the remaining steps are the same as in Example 4, to obtain 9.8g of diene derivative d.

[0056] Example 7, a diene derivative and a method for preparing the same Compared with Example 4, the difference in Example 7 is that in step (1), sodium hydroxide is replaced with potassium tert-butoxide, and the remaining steps are the same as in Example 4, to obtain 2.3g of diene derivative d.

[0057] Example 8, a diene derivative and a method for preparing the same Compared with Example 4, the difference in Example 8 is that in step (1), the 40% H2SO4 was replaced with 20% hydrochloric acid, and the rest of the steps were the same as in Example 4, resulting in 11.2g of diene derivative d.

[0058] Example 9, a diene derivative and a method for preparing the same Compared with Example 4, the difference in Example 9 is that in step (1), the 40% H2SO4 was replaced with a 20% citric acid solution, and the remaining steps were the same as in Example 4, resulting in 7.3g of diene derivative d.

[0059] Example 10, a diene derivative and a method for preparing the same Compared with Example 4, the difference in Example 10 is that in step (1), the 40% H2SO4 was replaced with a 40% acetic acid solution, and the remaining steps were the same as in Example 4, resulting in 6.5g of diene derivative d.

[0060] Example 11, a diene derivative and a method for preparing the same Compared with Example 4, the difference in Example 11 is that in step (1), the temperature is raised to 80°C and heated for 10 h, while the remaining steps are the same as in Example 4, yielding 12.1 g of diene derivative d.

[0061] Example 12, a diene derivative and a method for preparing the same Compared with Example 4, the difference in Example 12 is that in step (1), the amount of sodium hydroxide is adjusted to 32.2g and water is added to 200mL. The remaining steps are the same as in Example 4, and 14.5g of diene derivative d is obtained.

[0062] Example 13, a diene derivative and a method for preparing the same Compared with Example 4, the difference in Example 13 is that in step (1), the amount of sodium hydroxide solid added is 12g, water is added to 80mL, and the remaining steps are the same as in Example 4, to obtain 7.5g of diene derivative d.

[0063] Example 14, a diene derivative and a method for preparing the same Compared with Example 4, the difference in Example 14 is that in step (1), the temperature is raised to 60°C and heated for 14 hours. The remaining steps are the same as in Example 4, and 14.8g of diene derivative d is obtained.

[0064] Example 15, a diene derivative and a method for preparing the same Compared with Example 4, the difference in Example 15 is that in step (2), the horizontal screw centrifuge is replaced with a flat plate centrifuge, and the remaining steps are the same as in Example 4, to obtain 7.3g of diene derivative d.

[0065] Comparative Example 1 Compared with Example 4, the difference in Comparative Example 1 is that in step (1), 25.6g of sodium carbonate solid was weighed, placed in a 500mL reaction flask, 400mL of water was added and stirred to dissolve, 20.0g of chlorine was added, and the temperature was raised to 80℃ and heated for 10 h. The remaining steps were the same as in Example 4.

[0066] Liquid phase analysis of samples revealed no detectable diene derivatives. The basicity of sodium carbonate was insufficient to break the relatively stable cyclic imide bond, preventing the reaction from proceeding. The molecule contains multiple potential potentiophilic sites (multiple carbonyl and imine structures), and sodium carbonate was insufficient to provide a sufficient driving force and selectivity for the specific ring-opening reaction.

[0067] Comparative Example 2 Compared with Example 4, the difference in Comparative Example 2 is that in step (1), 25.6g of diisopropylamine solid was weighed, placed in a 500 mL reaction flask, 400 mL of water was added and stirred to dissolve, 20.0g of chlorine was added, and the temperature was raised to 80°C and heated for 10 h. The remaining steps were the same as in Example 4.

[0068] Liquid phase analysis of samples revealed that diene derivatives were not detected. The molecules contain multiple potential potentiophilic sites (multiple carbonyl groups and imine structures), and diisopropylamine is insufficient to provide enough driving force and selectivity for specific ring-opening reactions.

[0069] Comparative Example 3 Compared with Example 4, the difference in Comparative Example 3 is that in step (1), the temperature was raised to 40°C and the reaction was carried out for 10 h, while the remaining steps were the same as in Example 4. No obvious diene derivatives were detected in the samples.

[0070] Comparative Example 4 Compared with Example 4, the difference in Comparative Example 4 is that in step (1), the temperature was raised to 100°C and the reaction was carried out for 10 h, while the remaining steps were the same as in Example 4. No obvious diene derivatives were detected by sampling.

[0071] Comparative Example 5 Compared with Example 4, the difference in Comparative Example 5 is that in step (1), the amount of sodium hydroxide added is 1.0 g, the amount of water remains unchanged, and the remaining steps are the same as in Example 4. A sample was taken for liquid phase analysis, and the experimental results showed that the diene derivative was not detected. The low sodium hydroxide content resulted in weak nucleophilic attack kinetics, leading to reaction failure.

[0072] Comparative Example 6 Compared with Example 4, the difference in Comparative Example 6 is that in step (1), the amount of sodium hydroxide added is 30.0 g and the amount of water is 100 mL, while the rest of the steps are the same as in Example 4. A sample was taken for liquid phase analysis. The experimental results showed that the diene derivative was not detected, but the sodium hydroxide content was too high, leading to excessive hydrolysis of the open-ring imide bond, destruction of the conjugated skeleton, generation of uncontrollable fragments, and ultimately, reaction failure.

[0073] Comparative Example 7 Compared with Example 4, the difference in Comparative Example 7 is that in step (1), the temperature was raised to 60°C and heated for 2 hours, while the remaining steps were the same as in Example 4. Samples were taken for liquid phase analysis. The experimental results showed that the peak area of ​​the diene derivative was less than 5%, indicating that the ring-opening reaction required continuous attack by OH-, and the energy barrier was difficult to overcome in a short time, resulting in a low content of reaction products.

[0074] Comparative Example 8 Compared with Example 4, the difference of Comparative Example 8 is that in step (1), the temperature is raised to 60°C and heated for 24 hours, while the other steps are the same as in Example 4.

[0075] Samples were taken for liquid phase analysis. The experimental results showed that the peak area of ​​the diene derivative was less than 10%. The reaction time was too long, which led to excessive hydrolysis of the open-ring imide bond, destroying the conjugated skeleton, generating uncontrollable fragments, destroying the generated product, and resulting in a decrease in the reaction content.

[0076] Comparative Example 9 Compared with Example 4, the difference of Comparative Example 9 is that step (2) does not require acid adjustment, but is directly separated after alkaline water + blue reaction; the remaining steps are the same as in Example 4.

[0077] The separation revealed no obvious solid diene derivatives precipitated, indicating that adjusting with acid is not feasible.

[0078] Comparative Example 10 Compared with Example 4, the difference in Comparative Example 10 is that in step (2), the pH is adjusted to 8-9 with 40% sulfuric acid, and the rest of the steps are the same as in Example 4.

[0079] Samples were taken for liquid phase analysis. The experimental results showed that diene derivatives were not detected because diene derivatives exist as salts under alkaline conditions.

[0080] Test Example, application of a diene derivative to dyeing The diene derivatives d and b obtained in the above embodiments were used to dye cotton textiles according to the following process: Diene derivative 2% (owf), reduced with 2 times sodium hydrosulfite, adjusted to pH 5 with 0.5 mL / L citric acid, stained at 25℃ for 10 min, bath ratio 1:30.

[0081] After dyeing, the dyed fabric sample is removed, washed, and dried. The K / S value of the dye is then calculated using the Lambert-Beer law.

[0082] Test the dyes according to the standard and record the test results in Table 6 below.

[0083] Table 6 The results show that diene derivatives d and b can dye fabrics with a K / S value of over 10 and a dyeing rate of over 85%. The color fastness to washing, sublimation, acid spots, light exposure, and wet rubbing all reach grade 4 or higher. Compared to lemon yellow, the derivatives of this application exhibit better dyeing effects.

[0084] Powder and staining images of diene derivative d are shown below. Figure 10 As shown; powder and staining diagram of diene derivative b are shown below. Figure 11 As shown.

[0085] Based on existing blue pigments, this application obtains diene derivatives through chemical synthesis. These derivatives exhibit stable color, are resistant to high and low temperatures under acidic conditions, and have a wide range of applications and promising prospects for industrial production.

[0086] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of this application and are not intended to limit the scope of protection of this application. Although this application has been described in detail with reference to preferred embodiments, those skilled in the art should understand that modifications or equivalent substitutions can be made to the technical solutions of this application without departing from the substance and scope of the technical solutions of this application.

[0087] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of this application and are not intended to limit the scope of protection of this application. Although this application has been described in detail with reference to preferred embodiments, those skilled in the art should understand that modifications or equivalent substitutions can be made to the technical solutions of this application without departing from the substance and scope of the technical solutions of this application.

Claims

1. A diene derivative, characterized in that, The structural formula of the diene derivative is shown in Formula I; Formula I; Among them, Ra and Rb are one of -OH and -NH2; Rc is one of -OH and -COOH; Rd is one of the following three structures:

2. The diene derivative as described in claim 1, characterized in that, The diene derivatives include any one of the following structures:

3. The method for preparing diene derivatives as described in claim 1 or 2, characterized in that, Includes the following steps: The substrate Visin Blue was added to alkaline water and heated under reflux to obtain a reaction solution. The pH of the reaction solution was then adjusted to 2-6 with acid, followed by solid-liquid separation. The precipitate was obtained after separation and purification to obtain diene derivatives.

4. The method for preparing diene derivatives as described in claim 3, characterized in that, The alkaline solution is at least one of sodium hydroxide, sodium hydride, potassium hydroxide, and potassium tert-butoxide.

5. The method for preparing diene derivatives as described in claim 3, characterized in that, The acid is at least one of sulfuric acid, hydrochloric acid, acetic acid, and citric acid.

6. The method for preparing diene derivatives as described in claim 3, characterized in that, Adjust the pH of the reaction solution to 3-4 using acid.

7. The method for preparing diene derivatives as described in claim 3, characterized in that, The mass ratio of the blue violet and the alkaline water is 1:(2~50).

8. The method for preparing diene derivatives as described in claim 3, characterized in that, The conditions for the heating reflux reaction include: Add the substrate Visible Blue to alkaline water, heat and reflux at 60-80℃ for 8-14 hours, then cool to 5-10℃ to obtain the reaction solution.

9. The method for preparing diene derivatives as described in claim 3, characterized in that, The solid-liquid separation is performed using a solid-liquid separation instrument, which may be any one of a horizontal screw centrifuge, a flat plate centrifuge, or a plate and frame filter press.

10. The use of diene derivatives as described in claim 1 or 2 in the synthesis of organic dyes.

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