Preparation method of diphenyl ether anthraquinone dye
Through a new preparation method of diphenyl ether anthraquinone dye, the problems of poor solubility and high risk in the synthesis of existing anthraquinone dyes are solved, and high yield, high solubility and stable dye preparation are achieved, which is suitable for industrial production.
Patent Information
- Application Number
- CN202411750700.2
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Priority Date
- 2024-09-20
- Filing Date
- 2024-12-02
- Publication Date
- 2025-06-06
AI Technical Summary
The existing anthraquinone dyes have problems such as poor solubility, difficult synthesis, high risk of use of hazardous chemicals and high explosion during the synthesis process, and are difficult to synthesize dyes with asymmetric structures and low yields.
A method for preparing diphenyl ether anthraquinone dye with an asymmetric structure is adopted. Through specific reaction general formulas and process steps, common and easy-to-get raw materials are used to avoid heavy metal catalysts, control mild reaction conditions and improve yields.
The preparation of asymmetric structure anthraquinone dyes with high yields (more than 90%) has been achieved, which improves the solubility and stability of the dye, reduces the risk and cost of the process, and is suitable for industrial production.
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Figure CN120098465A_ABST
Abstract
Description
Technical Field
[0001] The present application belongs to the technical field of organic synthesis, and in particular relates to a method for preparing a diphenyl ether anthraquinone dye (diphenyl ether anthraquinone dye). Background Art
[0002] Guest-host liquid crystal refers to a liquid crystal as the main body, and a dichroic dye is added as the guest. Under the action of the electric field, the dichroic dye molecules are arranged along the arrangement of the liquid crystal. Because the dichroic dye absorbs light only in the direction of the long axis of the molecule and hardly absorbs light in the direction of the short axis, when the long axis direction of the dye and the liquid crystal molecule is parallel to the incident light, it appears colorless or light-colored, and when the long axis direction of the dye and the liquid crystal molecule is perpendicular to the incident light, it appears in a dark colored state or dark state. This dimming property of guest-host liquid crystal is widely used in the display field and dimming field. Dichroic dyes are mainly divided into two categories: azo type and anthraquinone type. Azo dyes usually have high order parameters and simple preparation methods. They have the advantages of good solubility, high absorption coefficient, high order and dichroic ratio in liquid crystals. However, compared with anthraquinone dyes, azo dyes have the disadvantages of poor thermal stability and poor light resistance. The application of guest-host liquid crystals in outdoor display screens, building curtain walls, and vehicles requires higher heat and light resistance products for dyes, and anthraquinone dyes are the best choice.
[0003] Traditional anthraquinone dyes usually have the disadvantages of poor solubility and large synthesis difficulty. In anthraquinone dyes, blue, blue-green or green dyes are used as dyes that are indispensable for mixing into black, usually containing some amino groups, hydroxyl groups, etc. On the one hand, there are many synthesis steps and dangerous operation process. Patent CN112980212 reports a preparation method of a blue anthraquinone dye, which requires the use of hazardous chemicals 1,5-dihydroxy-4,8-dinitroanthraquinone as substrate, and the second step uses nitrobenzene as solvent to do nitro substitution reaction with a large risk of explosion. On the other hand, some active groups such as amino groups and hydroxyl groups on the dye molecular skeleton react easily with the active groups (such as carboxyl) of the main material under light and heat conditions, and the color changes, so the dye stability of the inactive group is stronger. In addition, the anthraquinone dyes of asymmetric structure, although the solubility of the dye can be significantly improved, are difficult to synthesize and have low yield. Summary of the invention
[0004] In view of the above-mentioned deficiencies in the prior art, the present application provides a method for preparing diphenyl ether anthraquinone dyes having an asymmetric structure and high yield.
[0005] In order to solve the above technical problems, the technical solution adopted in the present application is: a method for preparing diphenyl ether anthraquinone dyes, and the corresponding reaction formula of the method is as follows:
[0006]
[0007] , and R in the above reaction formula1 and R 2 The groups represented are different.
[0008] Specifically, the preparation method of the diphenyl ether anthraquinone dye mentioned above in the present application, the reaction formula corresponding to the preparation steps is as follows: (1)
[0010] (2)
[0012]
[0013] And R in the above two steps 1 and R 2 The groups represented are different.
[0014] Furthermore, the R 1 =-C n H 2n+1 , n = 0 to 20; or R 1 =-OC n H 2n+1 , n = 1 to 20; or Among them, R 3 =-C n H2 n+1 , n=0~20; R 3 =-OC n H 2n+1 , n=1~20.
[0015] Furthermore, when R 3 =-OC n H 2n+1 , wherein n=1~8.
[0016] Furthermore, when R 3 =-OC n H 2n+1 , wherein n=1~5.
[0017] Furthermore, the R 2 =-C n H 2n+1 , n = 0 to 20; or R 2 =-OC n H 2n+1 , n = 1 to 20; or Among them, R 3 =-C n H 2n+1 , n = 0 to 20; or
[0018] R3 =-OC n H 2n+1 , n=1~20.
[0019] Furthermore, when R 3 =-OC n H 2n+1 , wherein n=1~8.
[0020] Furthermore, when R 3 =-OC n H 2n+1 , wherein n=1~5.
[0021] More specifically, the preparation method of the diphenyl ether anthraquinone dye mentioned above in the present application comprises the following steps:
[0022] (1) Compound 1,4-difluoroanthraquinone and p-aminobenzene A base is dissolved in an organic solvent, and the reaction is controlled at a temperature range of 60 to 120° C. for 16 hours to 5 days under a protective gas environment to obtain a compound of formula A;
[0023] (2) Then compound A and compound Base, heating and stirring in an organic solvent to react to obtain the target product.
[0024] Furthermore, the organic solvent in step (1) is selected from one or more combinations of solvents such as DIEA (N,N-diisopropylethylamine), 1,4-dioxane, DMSO (dimethyl sulfoxide), and DME (dimethyl ether).
[0025] Furthermore, the organic solvent in step (1) is selected from at least one of 1,4-dioxane and DMSO.
[0026] Furthermore, the base in step (1) is selected from at least one of potassium phosphate, potassium carbonate, cesium carbonate, sodium carbonate and sodium hydroxide.
[0027] Furthermore, the base in step (1) is potassium carbonate.
[0028] Furthermore, the raw material described in step (1) The molar ratio of the raw material 1,4-difluoroanthraquinone is 1.0 to 1.7:1, and more preferably 1.0 to 1.6:1.
[0029] Furthermore, the molar ratio of the base in step (1) to the raw material 1,4-difluoroanthraquinone is 1.5 to 3.0:1.
[0030] Furthermore, the reaction temperature in step (1) is in the range of 70 to 120° C., and the reaction time is controlled to be 16 to 120 hours.
[0031] Furthermore, the reaction time in step (1) is 24 h to 120 h.
[0032] Furthermore, the organic solvent in step (2) is selected from at least one of DIEA (N,N-diisopropylethylamine), 1,4-dioxane, DMSO and DME.
[0033] Furthermore, the organic solvent in step (2) is at least one of 1,4-dioxane and DMSO.
[0034] Furthermore, the base described in step (2) is selected from at least one of sodium hydride, sodium hydroxide, potassium hydroxide, potassium carbonate and sodium carbonate.
[0035] Furthermore, the base in step (2) is selected from at least one of potassium carbonate, sodium carbonate and cesium carbonate.
[0036] Furthermore, the raw material described in step (2) The molar ratio of the compound A is 1.0 to 1.7:1, and more preferably 1.0 to 1.6:1.
[0037] Furthermore, the molar ratio of the base in step (2) to compound A is 1.5 to 4.0:1.
[0038] Furthermore, the reaction temperature in step (2) is 70-120° C., and the reaction time is 8-24 h.
[0039] Furthermore, the reaction temperature in step (2) is 80-130° C., and the reaction time is 12-24 h.
[0040] Advantages and beneficial effects of this application:
[0041] 1. The present application provides a method for preparing diphenyl ether anthraquinone dyes. The raw materials are common and easily available, and the reaction process does not require the use of heavy metal catalysts. The process operation is simple, the reaction conditions are mild, the purification is easy, the cost is low, and it is suitable for industrial production.
[0042] 2. The preparation method of diphenyl ether anthraquinone dyes provided in the present application does not use the hazardous chemical 1,5-dihydroxy-4,8-dinitroanthraquinone as a substrate in the reaction process, nor does it use nitrobenzene with a high explosion risk as a solvent for the nitro substitution reaction. Therefore, the entire operation process is safer and more environmentally friendly.
[0043] 3. The preparation method of diphenyl ether anthraquinone dyes provided in the present application improves the yield of the final product by setting specific raw materials and specific steps, and the yield can reach more than 90%.
[0044] 4. The preparation method of diphenyl ether anthraquinone dyes provided in the present application can ultimately obtain asymmetric anthraquinone dyes with higher yields, and this type of dye has better solubility and stability, thus facilitating subsequent applications; and the specific synthesis process of the present application is simple and easy to operate, low in cost, and easy to industrialize. BRIEF DESCRIPTION OF THE DRAWINGS
[0045] Figure 1 The product prepared in Example 1 of the present application 1 H NMR spectra.
[0046] Figure 2 The product prepared in Example 2 of the present application 1 H NMR spectra.
[0047] Figure 3 The product prepared in Example 3 of the present application 1 H NMR spectra.
[0048] Figure 4 The product prepared in Example 4 of the present application 1 H NMR spectra.
[0049] Figure 5 The product prepared in Example 5 of the present application 1 H NMR spectra. DETAILED DESCRIPTION
[0050] The present application can be further described in detail with reference to the following examples; however, the following examples are merely illustrative, and the present application is not limited to these examples.
[0051] Example 1
[0052] In this embodiment, the reaction formula of the compound prepared therefrom is as follows:
[0053]
[0054]
[0055] Step (1): First, 20 g of 1,4-difluoroanthraquinone, 21.35 g of 4-pentylaniline, 33.9 g of K 2 CO 3 Dissolved in 400 ml of 1,4-dioxane, then heated and stirred at 100° C. for 48 h; after the reaction was completed, the mixture was poured into water, extracted with ethyl acetate, and the solvent was removed to obtain a crude product, which was passed through a silica gel column (the eluent of the silica gel column was the following volume ratio: petroleum ether / ethyl acetate=20:1), and then distilled to remove the solvent to obtain a total of 7.5 g of compound A, and its yield was calculated to be 24.0%;
[0056] Step (2): 5.0 g of the compound A prepared in step (1), 3.4 g of 4-octyloxyaniline and 5.3 g of potassium carbonate were dissolved in 100 ml of DMSO solution, and heated and stirred at 130° C. for 16 h; then the mixture after the reaction was completed was poured into water, extracted with ethyl acetate, and the solvent was removed to obtain a crude product, which was passed through a silica gel column (the eluent of the silica gel column was a volume ratio of petroleum ether / ethyl acetate = 30:1) to finally obtain 5.5 g of compound B, with a calculated yield of 90%. The compound B was tested, and its nuclear magnetic resonance was as follows: Figure 1 As shown, the spectrum results of the nuclear magnetic resonance detection show that the synthesized product is
[0057] Example 2
[0058] In this embodiment, the reaction formula of the compound prepared therefrom is as follows:
[0059]
[0060] Step (1): First, 20 g of 1,4-difluoroanthraquinone, 17.4 g of 4-cyclohexylaniline, 22.6 g of K 2 CO 3 Dissolved in 400 ml of 1,4-dioxane, then heated and stirred at 80°C for 120 h; after the reaction was completed, the mixture was poured into water, then extracted with ethyl acetate, the solvent was removed to obtain a crude product, and then passed through a silica gel column (petroleum ether / ethyl acetate = 15:1) to finally obtain 10.0 g of compound C, with a calculated yield of 30.7%;
[0061] Step 2(1): 10.0 g of the compound C prepared in step (1), 6.1 g of 4-pentylaniline and 13.76 g of potassium carbonate were dissolved in 200 ml of DMSO solution, and then heated to 80°C with stirring for 24 h. After the reaction was completed, the mixture was poured into water, and then extracted with ethyl acetate to remove the solvent to obtain a crude product, which was then passed through a silica gel column (the eluent of the silica gel column was in a volume ratio of 1:5:1) to finally obtain 12.5 g of compound B, with a calculated yield of 92%. NMR showed Figure 2 As shown, the spectrum results of the nuclear magnetic resonance detection show that the synthesized product is:
[0062]
[0063] Therefore, it can be seen from the above examples that the preparation method of the present application can synthesize diphenyl ether dye substances with asymmetric structures, and its reaction conditions are mild, the operation is convenient, it can be applied to industrial production, and the yield is high, and the yield can reach more than 90%.
[0064] Example 3
[0065] In this embodiment, the reaction formula of the compound prepared therefrom is as follows:
[0066]
[0067] Step (1): First, 20 g of 1,4-difluoroanthraquinone, 7.63 g of aminobenzene, 16.98 g of K 2 CO 3 Dissolve in 400 ml of 1,4-dioxane, then heat and stir at 130°C for 72 h; after the reaction is completed, pour the mixture into water, then extract with ethyl acetate, remove the solvent to obtain a crude product, then pass through a silica gel column (petroleum ether / ethyl acetate = 15:1), and finally obtain 8.50 g of compound C, with a calculated yield of 32.7%;
[0068] Step (2): 8.5 g of the compound C prepared in step (1), 9.9 g of 4-pentylaniline and 13.76 g of potassium carbonate were dissolved in 160 ml of DMSO solution, and then heated to 130° C. and stirred for reaction for 12 h. After the reaction was completed, the mixture was poured into water, and then extracted with ethyl acetate to remove the solvent to obtain a crude product, which was then passed through a silica gel column (the eluent of the silica gel column was in a volume ratio of 1:15:1) to finally obtain 10.15 g of the compound, with a calculated yield of 90%. NMR showed Figure 3 As shown, the spectrum results of the nuclear magnetic resonance detection show that the synthesized product is:
[0069] Example 4
[0070]
[0071] Step (1): First, 20 g of 1,4-difluoroanthraquinone, 45.9 g of 4-eicosylaniline, 16.98 g of K 2 CO 3 Dissolve in 400 ml of 1,4-dioxane, then heat and stir at 110°C for 48 hours; after the reaction is completed, pour the mixture into water, then extract with ethyl acetate, remove the solvent to obtain a crude product, and then pass through a silica gel column (petroleum ether / ethyl acetate = 18:1) to finally obtain 17.1 g of the target compound, with a calculated yield of 35.0%;
[0072] Step (2): 15 g of the compound prepared in step (1), 1 g of 4-eicosyloxyaniline and 13.76 g of potassium carbonate were dissolved in 160 ml of DMSO solution, and then heated to 110° C. with stirring for 18 h; after the reaction was completed, the mixture was poured into water, and then extracted with ethyl acetate, and the solvent was removed to obtain a crude product, which was then passed through a silica gel column (the eluent of the silica gel column was in a volume ratio of 1:1:1) to finally obtain 22.1 g of the compound, with a calculated yield of 91%. NMR showed Figure 4 As shown, the spectrum results of the nuclear magnetic resonance detection show that the synthesized product is:
[0073] Example 5
[0074]
[0075] Step (1): First, 20 g of 1,4-difluoroanthraquinone, 16.05 g of 4-pentylaniline, 16.98 g of K 2 CO 3 Dissolve in 400 ml of 1,4-dioxane, then heat and stir at 100°C for 50 h; after the reaction is completed, pour the mixture into water, then extract with ethyl acetate, remove the solvent to obtain a crude product, then pass through a silica gel column (petroleum ether / ethyl acetate = 15:1), and finally obtain 9.52 g of the target compound, with a calculated yield of 30.0%;
[0076] Step (2): 9.52 g of the compound prepared in step (1), 1 g of 4-eicosyloxyaniline and 8.48 g of potassium carbonate were dissolved in 160 ml of DMSO solution, and then heated at 100° C. and stirred for reaction for 20 h; after the reaction was completed, the mixture was poured into water, and then extracted with ethyl acetate, and the solvent was removed to obtain a crude product, which was then passed through a silica gel column (the eluent of the silica gel column was in a volume ratio of 1:1:1) to finally obtain 14.56 g of the compound, with a calculated yield of 90.5%. NMR showed Figure 5 As shown, the spectrum results of the nuclear magnetic resonance detection show that the synthesized product is:
[0077]
[0078] It can be seen from the above test results that the product prepared in Example 2 of the present application is the compound obtained on the right side of the reaction formula in Example 2 of the present application.
Claims
1. A method for preparing a diphenyl ether anthraquinone dye, characterized in that: The reaction formula corresponding to this method is as follows: ， Furthermore, the groups represented by R1 and R2 in the above reaction formula are different.
2. The method for preparing diphenyl ether anthraquinone dye according to claim 1, characterized in that: The reaction formula corresponding to the preparation steps is as follows: (1) (2) Furthermore, the groups represented by R1 and R2 in the above two reaction steps are different.
3. The method for preparing diphenyl ether anthraquinone dye according to claim 3, characterized in that: The reaction step (1) Where R1=-C n H 2n+1 , n = 0 to 20; Or R1=-OC n H 2n+1 , n = 1 to 20; or Where R3=-C n H2 n+1 , n=0~20; R3=-OC n H2 n+1 , n=1~20.
4. The method for preparing diphenyl ether anthraquinone dye according to claim 3, characterized in that: When R3=-OC n H2 n+1 , Said n=1~8.
5. The method for preparing diphenyl ether anthraquinone dye according to claim 4, characterized in that: When R3=-OC n H2 n+1 , Said n=1~5.
6. The method for preparing diphenyl ether anthraquinone dyes according to claim 3, characterized in that: Reaction step (2) The Where R2=-C n H 2n+1 , n = 0 to 20; Or R2=-OC n H 2n+1 , n = 0 to 20; or Where R3=-C n H 2n+1 , n = 0 to 20; or R3=-OC n H 2n+1 ,n=1~20。 7. The method for preparing diphenyl ether anthraquinone dyes according to claim 6, characterized in that: When R3=-OC n H 2n+1 , wherein n=1~8.
8. The method for preparing diphenyl ether anthraquinone dyes according to claim 7, characterized in that: When R3=-OC n H 2n+1 , wherein n=1~5.
9. A method for preparing a diphenyl ether anthraquinone dye according to any one of claims 2 to 8, characterized in that: The preparation process includes: (1) Compound 1,4-difluoroanthraquinone and p-aminobenzene A base is dissolved in an organic solvent, and the reaction is controlled at a temperature range of 60 to 120° C. for 16 hours to 5 days under a protective gas environment to obtain a compound of formula A; (2) Then compound A and compound Base, heating and stirring in an organic solvent to react to obtain the target product.
10. The method for preparing diphenyl ether anthraquinone dyes according to claim 9, characterized in that: The organic solvent in step (1) is selected from one or more combinations of DIEA, 1,4-dioxane, DMSO, and DME solvents; the base in step (1) is selected from at least one of potassium phosphate, potassium carbonate, cesium carbonate, sodium carbonate, and sodium hydroxide.
11. The method for preparing diphenyl ether anthraquinone dyes according to claim 10, characterized in that: The organic solvent in step (1) is selected from at least one of 1,4-dioxane and DMSO; the base in step (1) is potassium carbonate.
12. The method for preparing diphenyl ether anthraquinone dyes according to claim 9, characterized in that: The raw materials described in step (1) The molar ratio of the alkali to the raw material 1,4-difluoroanthraquinone is 1.0-1.5:1; the molar ratio of the alkali described in step (1) to the raw material 1,4-difluoroanthraquinone is 1.5-3.0:1; the reaction temperature described in step (1) is within the temperature range of 70-120°C, and the reaction time is controlled to be 16h-120h.
13. The method for preparing diphenyl ether anthraquinone dyes according to claim 9, characterized in that: The organic solvent in step (2) is selected from at least one of DIEA, 1,4-dioxane, DMSO, and DME; the base in step (2) is selected from at least one of sodium hydride, sodium hydroxide, potassium hydroxide, potassium carbonate, and sodium carbonate.
14. The method for preparing diphenyl ether anthraquinone dyes according to claim 13, characterized in that: The organic solvent in step (2) is at least one of 1,4-dioxane and DMSO; the base in step (2) is at least one of potassium carbonate, sodium carbonate and cesium carbonate.
15. The method for preparing diphenyl ether anthraquinone dyes according to claim 9, characterized in that: The raw materials described in step (2) The molar ratio of the base to the compound A is 1.0 to 1.5:1; the molar ratio of the base to the compound A in step (2) is 1.5 to 4.0:1; the reaction temperature in step (2) is 70 to 120°C, and the reaction time is 8 to 24 hours.