Process for the synthesis of a disperse dye coupling component containing a tetrahydroquinoline structure and its use

Abstract

This invention relates to the synthesis of disperse dyes, specifically a method for synthesizing a disperse dye coupling component containing a tetrahydroquinoline structure and its application. Specifically, using m-hydroxyaniline (II) and acrylate as raw materials, an N,N-dialkylation reaction is carried out under catalysis at 70-120°C to obtain intermediate (IV). This intermediate undergoes an intramolecular cyclization reaction to obtain the coupling component of the disperse azo dye containing a tetrahydroquinoline derivative, as shown in formula (I). Compared with conventional methods for synthesizing tetrahydroquinoline compounds, the synthesis method of this invention is milder and less hazardous. Compared with multi-step synthesis methods used domestically and internationally, it has the advantage of a shorter route. Simultaneously, the yield is relatively high.

Description

Technical Field

[0001] This invention relates to the synthesis of disperse dyes, specifically a method for synthesizing a disperse dye coupling component containing a tetrahydroquinoline structure and its application. Background Technology

[0002] In recent years, spandex elastic fabrics have achieved performance levels that are unmatched by ordinary fabrics. These products have excellent resilience, a soft feel, are easy to absorb sweat, and do not generate static electricity. However, these fabrics are generally dyed with disperse dyes. Disperse dyes generally have a high affinity for spandex and good dyeability, which leads to severe staining of spandex by disperse dyes. This causes significant problems in the dyeing and processing of products with high requirements for color fastness.

[0003] Heterocyclic disperse dyes made from tetrahydroquinoline and its derivatives exhibit excellent fastness and good strengthening properties in immersion dyeing, printing, and hot melt dyeing, showing broad development prospects. Tetrahydroquinoline compounds are a very important class of N-heterocyclic aromatic compounds. Tetrahydroquinoline derivatives with complex and variable structures are important components in the modern pharmaceutical field. At the same time, they also have good electron-donating chromophores and can be used as intermediates in the synthesis of disperse dyes. Therefore, disperse dyes containing tetrahydroquinoline structures have attracted widespread attention.

[0004] Literature search revealed that patent WO2015062937 discloses a specific group of azotetrahydroquinoline disperse dyes suitable for textile dyeing, exhibiting superior performance compared to known disperse dyes, and providing a method for diazotizing the corresponding diazonium salt with a coupling component containing a tetrahydroquinoline structure. Patents CN115124858A and CN110835473A disclose compositions containing tetrahydroquinoline disperse dyes, which, when applied to the dyeing of hydrophobic fiber materials, exhibit characteristics such as good sublimation staining fastness and good washing staining fastness. However, these patents do not disclose the preparation method of their key intermediate, the tetrahydroquinoline structure coupling component.

[0005] Tetrahydroquinoline compounds were initially synthesized via the hydrogenation reduction of quinoline, but the need for hydrogen gas posed a certain degree of danger. Currently, a more common synthetic method involves a metal-catalyzed Diels-Alder reaction of aniline derivatives and aldehydes under acidic conditions, but the substrate applicability is not widespread. Recently, multi-step and multi-component reaction synthesis methods have been developed both domestically and internationally. However, these methods are cumbersome and difficult to scale up for industrial production. Therefore, finding a method to efficiently obtain the target product under relatively mild and safe conditions is crucial. Summary of the Invention

[0006] This invention provides a method for synthesizing a disperse dye coupling component containing a tetrahydroquinoline structure and its application.

[0007] To achieve the above objectives, the present invention adopts the following technical solution:

[0008] A method for synthesizing a disperse dye coupling component containing a tetrahydroquinoline structure: Reaction formula

[0009]

[0010] Using m-hydroxyaniline (II) and acrylate as raw materials, N,N-dialkylation reaction was carried out under catalysis at 70-120℃ to obtain intermediate (IV). The intermediate underwent intramolecular cyclization reaction to obtain the coupling component containing tetrahydroquinoline derivative disperse azo dye as shown in formula (I).

[0011] In the reaction formula, R is a C1-C4 alkyl, C1-C4 alkoxyalkyl, or benzyl.

[0012] Furthermore, using m-hydroxyaniline (II) and acrylate as raw materials, an N,N-dialkylation reaction is carried out under catalysis at 70-120℃ to obtain intermediate (IV). Then, PPA polyphosphate is used as a cyclizing agent and solvent to cyclize the intermediate at 80-110℃ for 1-4 hours. The reaction is purified to obtain the coupling component containing a tetrahydroquinoline derivative disperse azo dye as shown in formula (I).

[0013] Under a nitrogen atmosphere, acrylate, m-hydroxyaniline, and catalyst are mixed and then heated to 70-120℃ for 5-20 hours. After the reaction, the mixture is diluted with water, washed with alkali, extracted with ethyl acetate, and the organic layer is dried, filtered, and evaporated to obtain intermediate (Ⅳ). The amount of acrylate used is 3-8 times the weight of m-hydroxyaniline, the amount of catalyst used is 0.2-3 times the weight of m-hydroxyaniline, and the amount of dilution water used is 20-60 times the weight of m-hydroxyaniline.

[0014] The catalyst is one or more of acetic acid, anhydrous aluminum chloride, sodium bromide, hydrochloric acid, sulfuric acid, trimethylamine, and triethylamine.

[0015] The process involves mechanically stirring and heating PPA to 80-110°C, then adding the intermediate (Ⅳ) obtained above, stirring for 1-4 hours, cooling to 60°C, adding ice, stirring for 15-30 minutes until the reaction is complete, then extracting the organic layer with ethyl acetate, followed by alkali washing, water washing until neutral, drying, vacuum concentration, and column chromatography purification to obtain the coupling component containing the tetrahydroquinoline derivative disperse azo dye shown in formula (Ⅰ).

[0016] The amount of polyphosphate used is 15-25 times the weight of the intermediate body; the amount of ice added during the reaction is 50-100 times the weight of the intermediate body.

[0017] An application of the obtained disperse dye coupling component containing a tetrahydroquinoline structure, wherein the coupling component of the disperse azo dye containing a tetrahydroquinoline derivative as shown in formula (I) is used in the preparation of disperse azo dyes.

[0018] The structure of the disperse azo dye is as follows:

[0019]

[0020] In the structural formula: X1 is nitro, cyano, or halogen; X2 is halogen, preferably chlorine or bromine; R is C1-C4 alkyl, C1-C4 alkoxyalkyl, or benzyl.

[0021] Advantages of this invention:

[0022] The synthetic method of this invention is milder and less hazardous compared to conventional hydrogenation reduction methods for tetrahydroquinoline compounds. Compared to multi-step synthetic methods used domestically and internationally, it has the advantage of a shorter route and a relatively higher yield. Detailed implementation method:

[0023] The following examples further illustrate specific embodiments of the present invention. It should be noted that the specific embodiments described herein are merely for illustration and explanation and are not intended to limit the scope of the present invention.

[0024] The chemical reagents used in this invention are all provided by Sinopharm Group.

[0025] Example 1

[0026] N2 was introduced into the reaction apparatus. In a 100 mL three-necked flask, 5.46 g of m-hydroxyphenol, 25.86 g of methyl acrylate, 1.24 g of sodium bromide, and 6.2 mL of acetic acid were added. The mixture was stirred and heated to 95 °C for 18 h. After the reaction was complete, the reaction solution was poured into a beaker containing 150 mL of water, neutralized with 5% sodium bicarbonate solution, extracted with ethyl acetate, and the organic layer was dried over anhydrous sodium sulfate. The resulting product was then filtered and evaporated under reduced pressure to obtain methyl 3-hydroxy-N,N-dipropionate aniline (12.16 g, yield: 86.4%), with a purity of 95.1% as determined by high-performance liquid chromatography.

[0027] In a 100 mL three-necked flask, 40 g of polyphosphoric acid was added, and the mixture was heated to 90 °C with mechanical stirring. Then, 2.3 g of methyl 3-hydroxy-N,N-dipropionate aniline was slowly added, and the mixture was stirred for 2 h. Subsequently, the temperature was lowered to 60 °C, and 50 g of ice was added to the reaction solution. The mixture was stirred for 15 min until the reaction was complete. The solution was extracted with ethyl acetate, and the organic layer was neutralized with 15 mL of 5% sodium hydroxide solution, then washed with water until neutral, dried over anhydrous magnesium sulfate, and concentrated under reduced pressure to obtain a brown oily liquid. After purification by column chromatography, a yellow solid, methyl 1-propionate-5-hydroxy-1,2,3,4-tetrahydroquinoline-4-one (1.96 g, yield: 93.7%), was obtained.

[0028] Example 2

[0029] N2 was introduced into the reaction apparatus. In a 100 mL three-necked flask, 5.46 g of m-hydroxyphenol, 30.07 g of ethyl acrylate, and 10 g of anhydrous aluminum chloride were added. The mixture was stirred and heated to 70 °C for 5 h. After the reaction was complete, the reaction solution was poured into a beaker containing 150 mL of water, neutralized with 5% sodium bicarbonate solution, extracted with ethyl acetate, and the organic layer was dried over anhydrous sodium sulfate. The resulting product was then filtered and evaporated under reduced pressure to obtain 13.04 g of ethyl 3-hydroxy-N,N-dipropionate aniline (yield: 84.3%), with a purity of 93.9% as determined by high-performance liquid chromatography.

[0030] In a 100 mL three-necked flask, 40 g of polyphosphoric acid was added, and the mixture was heated to 80 °C with mechanical stirring. Then, 2.6 g of 3-hydroxy-N,N-dipropionate ethyl aniline was slowly added, and the mixture was stirred for 4 h. Subsequently, the temperature was lowered to 60 °C, and 50 g of ice was added to the reaction solution. The mixture was stirred for 30 min until the reaction was complete. The solution was extracted with ethyl acetate, and the organic layer was neutralized with 15 mL of 5% sodium hydroxide solution, then washed with water until neutral, dried over anhydrous magnesium sulfate, and concentrated under reduced pressure to obtain a brown oily liquid. After purification by column chromatography, a yellow solid, 1-propionate ethyl-5-hydroxy-1,2,3,4-tetrahydroquinoline-4-one (2.04 g, yield: 92.3%), was obtained.

[0031] Example 3

[0032] N2 was introduced into the reaction apparatus. In a 100 mL three-necked flask, 5.46 g of m-hydroxyphenol, 39.08 g of methoxyethyl acrylate, and 8 mL of acetic acid were added. The mixture was stirred and heated to 95 °C for 18 h. After the reaction was complete, the reaction solution was poured into a beaker containing 150 mL of water, neutralized with 5% sodium bicarbonate solution, extracted with ethyl acetate, and the organic layer was dried over anhydrous sodium sulfate. The resulting product was then filtered and evaporated under reduced pressure to obtain 3-hydroxy-N,N-dipropionic acid methoxyethyl aniline (15.26 g, yield: 82.61%), with a purity of 91.7% as determined by high-performance liquid chromatography.

[0033] In a 100 mL three-necked flask, 50 g of polyphosphoric acid was added, and the mixture was heated to 90 °C with mechanical stirring. Then, 3.1 g of 3-hydroxy-N,N-dipropionic acid methoxyethyl aniline was slowly added, and the mixture was stirred for 2 h. Subsequently, the temperature was lowered to 60 °C, and 60 g of ice was added to the reaction solution. The mixture was stirred for 15 min until the reaction was complete. The solution was extracted with ethyl acetate, and the organic layer was neutralized with 20 mL of 5% sodium hydroxide solution, then washed with water until neutral, dried over anhydrous magnesium sulfate, and concentrated under reduced pressure to obtain a brown oily liquid. After purification by column chromatography, a yellow solid, 1-propionic acid methoxyethyl 5-hydroxy-1,2,3,4-tetrahydroquinoline-4-one (2.31 g, yield: 93.8%), was obtained.

[0034] Example 4

[0035] N2 was introduced into the reaction apparatus. In a 100 mL three-necked flask, 5.46 g of m-hydroxyphenol, 44.4 g of benzyl acrylate, 1.24 g of sodium bromide, and 6.2 mL of acetic acid were added. The mixture was stirred and heated to 110 °C for 20 h. After the reaction was completed, the reaction solution was poured into a beaker containing 200 mL of water, neutralized with 5% sodium bicarbonate solution, extracted with ethyl acetate, and the organic layer was dried with anhydrous sodium sulfate. After filtration and vacuum evaporation, 11.4 g of 3-hydroxy-N,N-dipropionate benzyl aniline (yield: 87.5%) was obtained, and its purity was determined to be 80.3% using high-performance liquid chromatography.

[0036] In a 100 mL three-necked flask, 50 g of polyphosphoric acid was added, and the mixture was heated to 90 °C with mechanical stirring. Then, 2.3 g of methyl 3-hydroxy-N,N-dipropionate aniline was slowly added, and the mixture was stirred for 2 h. Subsequently, the temperature was lowered to 60 °C, and 50 g of ice was added to the reaction solution. The mixture was stirred for 30 min until the reaction was complete. The solution was extracted with ethyl acetate, and the organic layer was neutralized with 20 mL of 5% sodium hydroxide solution, then washed with water until neutral, dried over magnesium sulfate, and concentrated under reduced pressure to obtain a brown oily liquid. After purification by column chromatography, a yellow solid, 1-benzyl propionate-5-hydroxy-1,2,3,4-tetrahydroquinoline-4-one (2.13 g, yield: 81.5%), was obtained.

Claims

1. A method for synthesizing a disperse dye coupling component containing a tetrahydroquinoline structure, characterized in that: Reaction ； The reaction was carried out using m-hydroxyaniline (II) and acrylate as raw materials under catalysis at 70-120℃. N , N - Dialkylation reaction to obtain intermediate (Ⅳ), intermediate is subjected to intramolecular cyclization reaction to obtain coupling component of tetrahydroquinoline derivative disperse azo dye as shown in formula (Ⅰ); The intramolecular cyclization reaction uses polyphosphate PPA as the cyclizing agent; The catalyst is one or more of acetic acid, anhydrous aluminum chloride, and sodium bromide; In the reaction formula, R is a C1-C6 alkyl, C1-C6 alkoxyalkyl, or benzyl.

2. The method for synthesizing the disperse dye coupling component containing a tetrahydroquinoline structure according to claim 1, characterized in that: The reaction was carried out using m-hydroxyaniline (II) and acrylate as raw materials under catalysis at 70-120℃. N , N - Dialkylation reaction to obtain intermediate (Ⅳ), then cyclization reaction of intermediate with polyphosphate PPA as cyclizing agent and solvent at 80-110℃ for 1-4h, reaction purification to obtain coupling component containing tetrahydroquinoline derivative disperse azo dye as shown in formula (Ⅰ).

3. The method for synthesizing the disperse dye coupling component containing a tetrahydroquinoline structure according to claim 2, characterized in that: Under a nitrogen atmosphere, acrylate, m-hydroxyaniline, and catalyst are mixed and then heated to 70-120℃ for 5-20 hours. After the reaction, the mixture is diluted with water, washed with alkali, extracted with ethyl acetate, and the organic layer is dried, then filtered and evaporated to obtain intermediate (Ⅳ). The amount of acrylate used is 3-8 times the weight of m-hydroxyaniline, the amount of catalyst used is 0.2-3 times the weight of m-hydroxyaniline, and the amount of dilution water used is 20-60 times the weight of m-hydroxyaniline.

4. The method for synthesizing the disperse dye coupling component containing a tetrahydroquinoline structure according to claim 2, characterized in that: The process involves mechanically stirring and heating PPA to 80-110°C, then adding the intermediate (Ⅳ) obtained above, stirring for 1-4 hours, cooling to 60°C, adding ice, stirring for 15-30 minutes until the reaction is complete, then extracting the organic layer with ethyl acetate, followed by alkali washing, water washing until neutral, drying, vacuum concentration, and column chromatography purification to obtain the coupling component containing the tetrahydroquinoline derivative disperse azo dye shown in formula (Ⅰ).

5. The method for synthesizing the disperse dye coupling component containing a tetrahydroquinoline structure according to claim 4, characterized in that: The amount of polyphosphate used is 15-25 times the weight of the intermediate body; the amount of ice added during the reaction is 50-100 times the weight of the intermediate body.

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