CN116969836A - Preparation method of antioxidant 1076 - Google Patents
Preparation method of antioxidant 1076 Download PDFInfo
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- CN116969836A CN116969836A CN202310901858.4A CN202310901858A CN116969836A CN 116969836 A CN116969836 A CN 116969836A CN 202310901858 A CN202310901858 A CN 202310901858A CN 116969836 A CN116969836 A CN 116969836A
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- antioxidant
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- hydroxyphenyl
- tert
- butyl
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- SSDSCDGVMJFTEQ-UHFFFAOYSA-N octadecyl 3-(3,5-ditert-butyl-4-hydroxyphenyl)propanoate Chemical compound CCCCCCCCCCCCCCCCCCOC(=O)CCC1=CC(C(C)(C)C)=C(O)C(C(C)(C)C)=C1 SSDSCDGVMJFTEQ-UHFFFAOYSA-N 0.000 title claims abstract description 34
- 238000002360 preparation method Methods 0.000 title abstract description 11
- GLDOVTGHNKAZLK-UHFFFAOYSA-N octadecan-1-ol Chemical compound CCCCCCCCCCCCCCCCCCO GLDOVTGHNKAZLK-UHFFFAOYSA-N 0.000 claims abstract description 28
- 238000000034 method Methods 0.000 claims abstract description 16
- 238000006243 chemical reaction Methods 0.000 claims abstract description 14
- GOQYKNQRPGWPLP-UHFFFAOYSA-N n-heptadecyl alcohol Natural products CCCCCCCCCCCCCCCCCO GOQYKNQRPGWPLP-UHFFFAOYSA-N 0.000 claims abstract description 14
- YMWUJEATGCHHMB-UHFFFAOYSA-N Dichloromethane Chemical compound ClCCl YMWUJEATGCHHMB-UHFFFAOYSA-N 0.000 claims abstract description 13
- WPMYUUITDBHVQZ-UHFFFAOYSA-N 3-(3,5-ditert-butyl-4-hydroxyphenyl)propanoic acid Chemical compound CC(C)(C)C1=CC(CCC(O)=O)=CC(C(C)(C)C)=C1O WPMYUUITDBHVQZ-UHFFFAOYSA-N 0.000 claims abstract description 12
- 239000003054 catalyst Substances 0.000 claims abstract description 12
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Chemical compound O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 claims abstract description 11
- 239000002253 acid Substances 0.000 claims abstract description 10
- 239000012190 activator Substances 0.000 claims abstract description 10
- 239000011259 mixed solution Substances 0.000 claims abstract description 10
- 238000003756 stirring Methods 0.000 claims abstract description 9
- VYPSYNLAJGMNEJ-UHFFFAOYSA-N Silicium dioxide Chemical compound O=[Si]=O VYPSYNLAJGMNEJ-UHFFFAOYSA-N 0.000 claims abstract description 8
- 239000000741 silica gel Substances 0.000 claims abstract description 8
- 229910002027 silica gel Inorganic materials 0.000 claims abstract description 8
- 238000001914 filtration Methods 0.000 claims abstract description 7
- 238000005406 washing Methods 0.000 claims abstract description 7
- 238000001816 cooling Methods 0.000 claims abstract description 6
- 239000008367 deionised water Substances 0.000 claims abstract description 6
- 229910021641 deionized water Inorganic materials 0.000 claims abstract description 6
- 239000000706 filtrate Substances 0.000 claims abstract description 5
- PMZURENOXWZQFD-UHFFFAOYSA-L Sodium Sulfate Chemical compound [Na+].[Na+].[O-]S([O-])(=O)=O PMZURENOXWZQFD-UHFFFAOYSA-L 0.000 claims abstract description 4
- 238000001035 drying Methods 0.000 claims abstract description 4
- 239000012074 organic phase Substances 0.000 claims abstract description 4
- 239000012071 phase Substances 0.000 claims abstract description 4
- 238000010992 reflux Methods 0.000 claims abstract description 4
- 239000000243 solution Substances 0.000 claims abstract description 4
- 238000002156 mixing Methods 0.000 claims abstract description 3
- IMNFDUFMRHMDMM-UHFFFAOYSA-N N-Heptane Chemical compound CCCCCCC IMNFDUFMRHMDMM-UHFFFAOYSA-N 0.000 claims description 33
- XEKOWRVHYACXOJ-UHFFFAOYSA-N Ethyl acetate Chemical compound CCOC(C)=O XEKOWRVHYACXOJ-UHFFFAOYSA-N 0.000 claims description 15
- 238000005886 esterification reaction Methods 0.000 claims description 10
- 239000003480 eluent Substances 0.000 claims description 9
- 238000002425 crystallisation Methods 0.000 claims description 5
- 230000008025 crystallization Effects 0.000 claims description 5
- VHYFNPMBLIVWCW-UHFFFAOYSA-N 4-Dimethylaminopyridine Chemical group CN(C)C1=CC=NC=C1 VHYFNPMBLIVWCW-UHFFFAOYSA-N 0.000 claims description 4
- 239000012065 filter cake Substances 0.000 claims description 3
- 238000010438 heat treatment Methods 0.000 claims description 3
- 238000011068 loading method Methods 0.000 claims description 3
- FPQQSJJWHUJYPU-UHFFFAOYSA-N 3-(dimethylamino)propyliminomethylidene-ethylazanium;chloride Chemical group Cl.CCN=C=NCCCN(C)C FPQQSJJWHUJYPU-UHFFFAOYSA-N 0.000 claims description 2
- 230000035484 reaction time Effects 0.000 claims description 2
- 239000003963 antioxidant agent Substances 0.000 abstract description 4
- 239000000203 mixture Substances 0.000 abstract description 2
- 230000000052 comparative effect Effects 0.000 description 9
- 239000000047 product Substances 0.000 description 6
- 239000006227 byproduct Substances 0.000 description 2
- 230000000694 effects Effects 0.000 description 2
- 238000005809 transesterification reaction Methods 0.000 description 2
- PXMJCECEFTYEKE-UHFFFAOYSA-N Benzenepropanoic acid, 3,5-bis(1,1-dimethylethyl)-4-hydroxy-, methyl ester Chemical compound COC(=O)CCC1=CC(C(C)(C)C)=C(O)C(C(C)(C)C)=C1 PXMJCECEFTYEKE-UHFFFAOYSA-N 0.000 description 1
- ISWSIDIOOBJBQZ-UHFFFAOYSA-N Phenol Chemical compound OC1=CC=CC=C1 ISWSIDIOOBJBQZ-UHFFFAOYSA-N 0.000 description 1
- 230000003078 antioxidant effect Effects 0.000 description 1
- 230000009286 beneficial effect Effects 0.000 description 1
- 230000003197 catalytic effect Effects 0.000 description 1
- 239000007795 chemical reaction product Substances 0.000 description 1
- 230000003247 decreasing effect Effects 0.000 description 1
- 239000012467 final product Substances 0.000 description 1
- 229910001385 heavy metal Inorganic materials 0.000 description 1
- 238000004128 high performance liquid chromatography Methods 0.000 description 1
- 239000012535 impurity Substances 0.000 description 1
- 238000004811 liquid chromatography Methods 0.000 description 1
- 230000004048 modification Effects 0.000 description 1
- 238000012986 modification Methods 0.000 description 1
- 231100000252 nontoxic Toxicity 0.000 description 1
- 230000003000 nontoxic effect Effects 0.000 description 1
- 238000000655 nuclear magnetic resonance spectrum Methods 0.000 description 1
- 230000003647 oxidation Effects 0.000 description 1
- 238000007254 oxidation reaction Methods 0.000 description 1
- 238000010525 oxidative degradation reaction Methods 0.000 description 1
- 239000000843 powder Substances 0.000 description 1
- 238000000746 purification Methods 0.000 description 1
- 238000011084 recovery Methods 0.000 description 1
- 238000000926 separation method Methods 0.000 description 1
- 239000007787 solid Substances 0.000 description 1
- 238000003809 water extraction Methods 0.000 description 1
Classifications
-
- C—CHEMISTRY; METALLURGY
- C07—ORGANIC CHEMISTRY
- C07C—ACYCLIC OR CARBOCYCLIC COMPOUNDS
- C07C67/00—Preparation of carboxylic acid esters
- C07C67/08—Preparation of carboxylic acid esters by reacting carboxylic acids or symmetrical anhydrides with the hydroxy or O-metal group of organic compounds
-
- C—CHEMISTRY; METALLURGY
- C07—ORGANIC CHEMISTRY
- C07C—ACYCLIC OR CARBOCYCLIC COMPOUNDS
- C07C67/00—Preparation of carboxylic acid esters
- C07C67/48—Separation; Purification; Stabilisation; Use of additives
-
- C—CHEMISTRY; METALLURGY
- C07—ORGANIC CHEMISTRY
- C07C—ACYCLIC OR CARBOCYCLIC COMPOUNDS
- C07C67/00—Preparation of carboxylic acid esters
- C07C67/48—Separation; Purification; Stabilisation; Use of additives
- C07C67/52—Separation; Purification; Stabilisation; Use of additives by change in the physical state, e.g. crystallisation
-
- C—CHEMISTRY; METALLURGY
- C07—ORGANIC CHEMISTRY
- C07C—ACYCLIC OR CARBOCYCLIC COMPOUNDS
- C07C67/00—Preparation of carboxylic acid esters
- C07C67/48—Separation; Purification; Stabilisation; Use of additives
- C07C67/56—Separation; Purification; Stabilisation; Use of additives by solid-liquid treatment; by chemisorption
-
- C—CHEMISTRY; METALLURGY
- C07—ORGANIC CHEMISTRY
- C07C—ACYCLIC OR CARBOCYCLIC COMPOUNDS
- C07C69/00—Esters of carboxylic acids; Esters of carbonic or haloformic acids
- C07C69/66—Esters of carboxylic acids having esterified carboxylic groups bound to acyclic carbon atoms and having any of the groups OH, O—metal, —CHO, keto, ether, acyloxy, groups, groups, or in the acid moiety
- C07C69/73—Esters of carboxylic acids having esterified carboxylic groups bound to acyclic carbon atoms and having any of the groups OH, O—metal, —CHO, keto, ether, acyloxy, groups, groups, or in the acid moiety of unsaturated acids
- C07C69/732—Esters of carboxylic acids having esterified carboxylic groups bound to acyclic carbon atoms and having any of the groups OH, O—metal, —CHO, keto, ether, acyloxy, groups, groups, or in the acid moiety of unsaturated acids of unsaturated hydroxy carboxylic acids
Landscapes
- Chemical & Material Sciences (AREA)
- Organic Chemistry (AREA)
- Crystallography & Structural Chemistry (AREA)
- Low-Molecular Organic Synthesis Reactions Using Catalysts (AREA)
- Organic Low-Molecular-Weight Compounds And Preparation Thereof (AREA)
Abstract
The application belongs to the field of antioxidants, and particularly discloses a preparation method of an antioxidant 1076. The preparation method comprises the following steps: adding methylene dichloride into a reaction vessel with a reflux device and a thermometer, sequentially adding 3- (3, 5-di-tert-butyl-4-hydroxyphenyl) propionic acid, stearyl alcohol and an acid activator, and stirring and mixing at room temperature; adding a catalyst into the mixed solution, and raising the temperature to perform the reaction. Adding deionized water after the reaction is finished to wash the mixture, and separating out a water phase after the washing is finished; adding anhydrous sodium sulfate into the organic phase to remove water, filtering, and concentrating the filtrate; purifying the concentrated solution by a silica gel column, cooling, crystallizing and drying to obtain the antioxidant 1076. The method is simple to operate, high-temperature and high-pressure equipment is not needed, the reaction efficiency is high, and the yield and purity of the obtained antioxidant 1076 are high.
Description
Technical Field
The application belongs to the field of antioxidants, and particularly relates to a preparation method of an antioxidant 1076.
Background
The antioxidant 1076 is a non-pollution nontoxic hindered phenol antioxidant, has the appearance of white or yellowish solid powder, has the advantages of low volatility, water extraction resistance, good compatibility and high oxidation resistance, and can be widely used in rubber and plastic products to prevent thermal oxidative degradation of the products. At present, a plurality of patent and literature reports on preparation methods of an antioxidant 1076, but most of the preparation methods are carried out by transesterification of methyl 3- (3, 5-di-tert-butyl-4-hydroxyphenyl) propionate and stearyl alcohol, and the preparation methods have the problems of high reaction temperature, rigorous selection of a used catalyst, low yield, difficult recovery and treatment of byproducts and the like.
Disclosure of Invention
In order to solve the problems, reduce the reaction temperature, improve the yield of the antioxidant 1076 and save energy, the application provides a preparation method of the antioxidant 1076.
The application provides a preparation method of an antioxidant 1076, which adopts the following technical scheme:
1. adding methylene dichloride into a reaction vessel with a reflux device and a thermometer, sequentially adding 3- (3, 5-di-tert-butyl-4-hydroxyphenyl) propionic acid, stearyl alcohol and an acid activator, and stirring and mixing at room temperature for 20min;
2. adding a catalyst into the mixed solution, heating to a certain temperature in a stirring state, and carrying out esterification reaction;
3. after the reaction is finished, adding deionized water into the mixed solution in the step (2) for washing for 10min, and standing after the washing is finished to separate out water phase; adding anhydrous sodium sulfate into the organic phase, stirring for 30min, filtering, and concentrating the filtrate;
4. loading the concentrated solution to a silica gel column washed by n-heptane, eluting the silica gel column by using a mixed solution of n-heptane and ethyl acetate, and collecting an eluent;
5. concentrating the eluent, adding n-heptane into the concentrated eluent, cooling for crystallization, filtering, and drying the filter cake to obtain the antioxidant 1076.
In the method, the antioxidant 1076 is prepared from 3- (3, 5-di-tert-butyl-4-hydroxyphenyl) propionic acid and stearyl alcohol through a medium-temperature esterification reaction under the action of an acid activator and a catalyst.
The molar ratio of the 3- (3, 5-di-tert-butyl-4-hydroxyphenyl) propionic acid to the stearyl alcohol to the acid activator to the catalyst is 1 (1.05-1.20) to 1.2:1.
The feeding amount of the methylene dichloride is 5 times of the mass of the 3- (3, 5-di-tert-butyl-4-hydroxyphenyl) propionic acid.
The acid activator is 1- (3-dimethylaminopropyl) -3-ethylcarbodiimide hydrochloride.
The catalyst is 4-dimethylaminopyridine.
The esterification reaction temperature was 40 ℃.
The esterification reaction time is 6-8 hours.
The mass of the deionized water is 5 times of that of the 3- (3, 5-di-tert-butyl-4-hydroxyphenyl) propionic acid.
And the mass ratio of the n-heptane to the ethyl acetate is 9:1.
The temperature of the cooling crystallization is 0-5 ℃.
Compared with the prior art, the application has the following beneficial effects:
the preparation method of the antioxidant 1076 provided by the application has the advantages that the reaction is carried out at a medium temperature of 40 ℃, the reaction condition is mild, the process is easy to control, and the energy is saved. The catalyst has high catalytic efficiency, no heavy metal residue, high yield up to 98%, high purity of reaction product up to 99%, and high efficiency compared with traditional transesterification process.
Description of the embodiments
The conception and the technical effects produced by the present application will be clearly and completely described below in connection with specific embodiments to fully understand the objects, features and effects of the present application. The described embodiments are only some, but not all, embodiments of the present application, and other embodiments, which a person skilled in the art would obtain without inventive faculty, are within the scope of protection of the present application.
The application will be further illustrated with reference to specific examples.
Examples
Example 1
Example 1 includes the following steps:
(1) 278g of methylene chloride is added into a reaction vessel with a reflux device and a thermometer, 55.6g of 3- (3, 5-di-tert-butyl-4-hydroxyphenyl) propionic acid, 56.7g of stearyl alcohol and 46g of acid activator are added in sequence, and stirred and mixed for 20min at room temperature;
(2) Adding 24g of catalyst into the mixed solution, heating to 40 ℃ under stirring, and carrying out esterification reaction;
(3) After the reaction is finished, 278g of deionized water is added into the mixed solution in the step (2) for washing for 10min, and after the washing is finished, the mixture is stood to separate out water phase; adding anhydrous sodium sulfate into the organic phase, stirring for 30min, filtering, and concentrating the filtrate;
(4) Loading the concentrated solution to a silica gel column washed by n-heptane, eluting the silica gel column by using a 9:1 mixed solution of the n-heptane and ethyl acetate, and collecting the eluent;
(5) Concentrating the eluent, adding n-heptane into the concentrated eluent, cooling to 0-5 ℃ for crystallization, filtering, and drying a filter cake to obtain the antioxidant 1076.
Example 2
Example 2 was substantially the same as example 1 except that stearyl alcohol was added in an amount of 59.4g in step (1).
Example 3
Example 3 was substantially the same as example 1 except that stearyl alcohol was added in an amount of 62.1g in step (1).
Example 4
Example 4 was substantially the same as example 1 except that stearyl alcohol was added in an amount of 64.8g in step (1).
Comparative example 1
Comparative example 1 differs from example 1 in that the filtrate in step (3) of comparative example 1 was directly concentrated and dried to obtain a final product.
The purity and yield of the antioxidant 1076 finished product prepared in examples 1-4 and comparative example 1 were analyzed by NMR spectrum and HPLC liquid chromatography, and the results are shown in Table 1.
TABLE 1 purity and yield of reactive antioxidants in examples 1-4 and comparative example 1
Numbering components | Antioxidant 1076 purity | Yield of antioxidant 1076 |
Example 1 | 99.2% | 99.3% |
Example 2 | 99.4% | 99.1% |
Example 3 | 99.5% | 98.7% |
Example 4 | 99.7% | 97.5% |
Comparative example 1 | 80.0% | 99.3% |
As shown in Table 1, in comparative examples 1 to 4, it can be seen that the esterification reaction was more complete by increasing the amount of stearyl alcohol added, which was advantageous for improving the purity of antioxidant 1076, but the yield of the product was decreased with the increase of the amount of stearyl alcohol added.
Comparative examples 1 to 4 and comparative example 1 show that the impurity byproducts and the antioxidant 1076 finished product can be separated by separation and purification through a silica gel column, thereby remarkably improving the purity of the product.
The present embodiment is only for explanation of the present application and is not to be construed as limiting the present application, and modifications to the present embodiment, which may not creatively contribute to the present application as required by those skilled in the art after reading the present specification, are all protected by patent laws within the scope of claims of the present application.
Claims (11)
1. A method for preparing an antioxidant 1076, wherein the method for preparing the antioxidant 1076 comprises the following steps:
(1) Adding methylene dichloride into a reaction vessel with a reflux device and a thermometer, sequentially adding 3- (3, 5-di-tert-butyl-4-hydroxyphenyl) propionic acid, stearyl alcohol and an acid activator, and stirring and mixing at room temperature for 20min;
(2) Adding a catalyst into the mixed solution, heating to a certain temperature in a stirring state, and carrying out esterification reaction;
(3) After the reaction is finished, adding deionized water into the mixed solution in the step (2) for washing for 10min, and standing after the washing is finished to separate out water phase; adding anhydrous sodium sulfate into the organic phase, stirring for 30min, filtering, and concentrating the filtrate;
(4) Loading the concentrated solution to a silica gel column washed by n-heptane, eluting the silica gel column by using a mixed solution of n-heptane and ethyl acetate, and collecting an eluent;
(5) Concentrating the eluent, adding n-heptane into the concentrated eluent, cooling for crystallization, filtering, and drying the filter cake to obtain the antioxidant 1076.
2. The method for preparing the antioxidant 1076 according to claim 1, wherein the antioxidant 1076 is prepared by a medium-temperature esterification reaction of 3- (3, 5-di-tert-butyl-4-hydroxyphenyl) propionic acid and stearyl alcohol under the action of an acid activator and a catalyst.
3. The method for preparing the antioxidant 1076 according to claim 1, wherein the molar ratio of 3- (3, 5-di-tert-butyl-4-hydroxyphenyl) propionic acid, stearyl alcohol, acid activator and catalyst is 1 (1.05-1.20): 1.2:1.
4. The method for preparing the antioxidant 1076 according to claim 1, wherein the feeding amount of the methylene dichloride is 5 times of the mass of the 3- (3, 5-di-tert-butyl-4-hydroxyphenyl) propionic acid.
5. The method of preparing an antioxidant 1076 according to claim 1, wherein the acid activator is
1- (3-dimethylaminopropyl) -3-ethylcarbodiimide hydrochloride.
6. The method for preparing the antioxidant 1076 according to claim 1, wherein the catalyst is
4-dimethylaminopyridine.
7. The method of preparing an antioxidant 1076 according to claim 1, wherein the esterification reaction temperature is 40 ℃.
8. The method for preparing the antioxidant 1076 according to claim 1, wherein the esterification reaction time is 6-8 hours.
9. The method for preparing the antioxidant 1076 according to claim 1, wherein the deionized water is 5 times the mass of 3- (3, 5-di-tert-butyl-4-hydroxyphenyl) propionic acid.
10. The method for preparing the antioxidant 1076 according to claim 1, wherein the mass ratio of the n-heptane to the ethyl acetate is 9:1.
11. The method for preparing the antioxidant 1076 according to claim 1, wherein the temperature of the cooling crystallization in the step (5) is 0-5 ℃.
Priority Applications (1)
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CN202310901858.4A CN116969836A (en) | 2023-07-21 | 2023-07-21 | Preparation method of antioxidant 1076 |
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CN202310901858.4A CN116969836A (en) | 2023-07-21 | 2023-07-21 | Preparation method of antioxidant 1076 |
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CN202310901858.4A Pending CN116969836A (en) | 2023-07-21 | 2023-07-21 | Preparation method of antioxidant 1076 |
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- 2023-07-21 CN CN202310901858.4A patent/CN116969836A/en active Pending
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