CN116283504B - Synthesis method of 2, 4-dicumyl phenol - Google Patents

Synthesis method of 2, 4-dicumyl phenol Download PDF

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CN116283504B
CN116283504B CN202310233055.6A CN202310233055A CN116283504B CN 116283504 B CN116283504 B CN 116283504B CN 202310233055 A CN202310233055 A CN 202310233055A CN 116283504 B CN116283504 B CN 116283504B
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phenol
graphene oxide
amount
reaction
cumylphenol
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CN116283504A (en
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郭永武
郭骄阳
赵崇鑫
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Jiangsu Jiyi New Material Co ltd
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    • C—CHEMISTRY; METALLURGY
    • C07—ORGANIC CHEMISTRY
    • C07C—ACYCLIC OR CARBOCYCLIC COMPOUNDS
    • C07C37/00—Preparation of compounds having hydroxy or O-metal groups bound to a carbon atom of a six-membered aromatic ring
    • C07C37/11—Preparation of compounds having hydroxy or O-metal groups bound to a carbon atom of a six-membered aromatic ring by reactions increasing the number of carbon atoms
    • C07C37/14—Preparation of compounds having hydroxy or O-metal groups bound to a carbon atom of a six-membered aromatic ring by reactions increasing the number of carbon atoms by addition reactions, i.e. reactions involving at least one carbon-to-carbon unsaturated bond
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
    • B01J—CHEMICAL OR PHYSICAL PROCESSES, e.g. CATALYSIS OR COLLOID CHEMISTRY; THEIR RELEVANT APPARATUS
    • B01J21/00—Catalysts comprising the elements, oxides, or hydroxides of magnesium, boron, aluminium, carbon, silicon, titanium, zirconium, or hafnium
    • B01J21/18—Carbon
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
    • B01J—CHEMICAL OR PHYSICAL PROCESSES, e.g. CATALYSIS OR COLLOID CHEMISTRY; THEIR RELEVANT APPARATUS
    • B01J31/00—Catalysts comprising hydrides, coordination complexes or organic compounds
    • B01J31/02—Catalysts comprising hydrides, coordination complexes or organic compounds containing organic compounds or metal hydrides
    • B01J31/0215—Sulfur-containing compounds
    • B01J31/0225—Sulfur-containing compounds comprising sulfonic acid groups or the corresponding salts
    • B01J35/19—
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
    • B01J—CHEMICAL OR PHYSICAL PROCESSES, e.g. CATALYSIS OR COLLOID CHEMISTRY; THEIR RELEVANT APPARATUS
    • B01J2231/00—Catalytic reactions performed with catalysts classified in B01J31/00
    • B01J2231/30—Addition reactions at carbon centres, i.e. to either C-C or C-X multiple bonds
    • B01J2231/32—Addition reactions to C=C or C-C triple bonds
    • Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
    • Y02P—CLIMATE CHANGE MITIGATION TECHNOLOGIES IN THE PRODUCTION OR PROCESSING OF GOODS
    • Y02P20/00—Technologies relating to chemical industry
    • Y02P20/50—Improvements relating to the production of bulk chemicals
    • Y02P20/52—Improvements relating to the production of bulk chemicals using catalysts, e.g. selective catalysts

Abstract

The invention provides a method for synthesizing 2, 4-dicumyl phenol. The method takes conventional acid catalysts such as p-toluenesulfonic acid and graphene oxide as a catalytic system, is obtained by reacting phenol and alpha-methylstyrene, has complete conversion of phenol and alpha-methylstyrene, and has high selectivity of 2, 4-cumylphenol, high product yield and less impurities; the method is simple to operate and has low cost of raw materials, so that the method has high practical value.

Description

Synthesis method of 2, 4-dicumyl phenol
Technical Field
The invention relates to the field of chemical industry, in particular to a method for synthesizing 2, 4-dicumyl phenol.
Background
2, 4-dicumylphenol (commonly called dicumylphenol) is an important fine chemical raw material, belongs to an important product in the dicumylphenol, is commonly used as an effective antioxidant for polyolefin, polycarbonate and fuel (gasoline and kerosene), or is used as an intermediate to synthesize other antioxidants, can be used as a bactericide, and has wide application in the fields of agricultural emulsifying agents, surfactants, antioxidants, ultraviolet absorbers, bactericides and the like.
With the continuous development of the products, the demand of the 2, 4-dicumyl phenol is continuously increased, and the speed is increased by about 20% per year.
In the literature at home and abroad, the synthesis of 2, 4-dicumyl phenol is mostly obtained by taking phenol and alpha-methyl styrene as synthesis raw materials and carrying out Friedel-crafts alkylation under the action of an acid catalyst. The reaction is as follows:
as can be seen from the above formula, the reaction of phenol with alpha-methylstyrene has a problem of multiple substitution, and in addition to the target product 2, 4-dicumylphenol, various alkylates such as 4-cumylphenol and 2,4, 6-tricumylphenol are simultaneously produced. This is because phenol and alpha-methylstyrene react in series to produce a mono-substituted 4-cumylphenol, which can continue to react to produce a di-substituted 2, 4-cumylphenol, and 2,4, 6-triscumylphenol, due to the activation of the benzene ring by the cumyl group. In addition, in the course of the reaction, α -methylstyrene may undergo self-polymerization to form various impurities such as dimers, trimers, etc., so that the yield of 2, 4-dicumylphenol is generally not high, and the reaction results are greatly different depending on different catalysts and reaction conditions. Reported catalysts include: p-toluenesulfonic acid, p-toluenesulfonic acid/tetrabutylammonium chloride, concentrated sulfuric acid, phosphoric acid/glacial acetic acid, cation exchange resins, aluminum phenoxide and the like, but most of the problems of low conversion rate and selectivity, low yield of 2, 4-dicumylphenol and the like exist.
Therefore, there is a need to develop more synthetic methods for 2, 4-dicumylphenol.
Disclosure of Invention
In order to solve the above problems in the prior art, the present invention provides a method for synthesizing 2, 4-dicumylphenol, which can prepare 2, 4-dicumylphenol with high selectivity and high yield.
In one embodiment, the synthesis method of 2, 4-dicumylphenol provided by the invention comprises the following steps:
under the protection of inert gas, adding molten phenol, an acid catalyst and graphene oxide into a reactor, uniformly stirring, heating to 50-80 ℃, slowly dropwise adding alpha-methyl styrene, and controlling the system temperature to 80-120 ℃; after the dripping is finished, the mixture reacts for 10min to 2h at the temperature to obtain the 2, 4-dicumyl phenol.
In a preferred embodiment, the method further comprises the steps of cooling to 50-75 ℃ after the reaction is finished, filtering to recover graphene oxide, adding alkali into the reaction liquid for neutralization, then extracting with an organic solvent, washing an organic phase, drying, removing the solvent, distilling residues to obtain crude 2, 4-cumylphenol, and recrystallizing to obtain a 2, 4-cumylphenol product.
In a preferred embodiment, the acidic catalyst is selected from at least one of sulfuric acid, methanesulfonic acid, p-toluenesulfonic acid, α -or β -naphthalenesulfonic acid, preferably p-toluenesulfonic acid. The amount of the acid catalyst used is 1 to 5% by mole, preferably 2 to 3% by mole, based on phenol.
In a preferred embodiment, the graphene oxide is used in an amount of 0.2 to 3% by mass, preferably 0.5 to 1.5% by mass, based on phenol. The graphene oxide is used as a cocatalyst, so that the activity of a catalytic system can be increased, and the flaky plane structure of the graphene oxide is beneficial to inhibiting the occurrence of trialkylation, so that the conversion of phenol and 4-cumylphenol can be enhanced, and the selectivity of 2, 4-cumylphenol can be improved.
Preferably, the graphene oxide may be prepared by the following method:
dispersing flake graphite in concentrated sulfuric acid, adding potassium permanganate, intercalating at normal temperature to obtain intercalated graphite, performing microwave expansion on the intercalated graphite to obtain expanded graphite, mixing the expanded graphite with the concentrated sulfuric acid and the potassium permanganate, oxidizing at 35-50 ℃, washing and drying the solid to obtain graphene oxide.
In a preferred embodiment, the amount of α -methylstyrene is from 2 to 2.2 times, preferably from 2 to 2.1 times the molar amount of phenol. When the amount of α -methylstyrene is too low, the proportion of 4-cumylphenol in the reaction mixture will be greatly increased, and when the amount of α -methylstyrene is too high, the proportion of 2,4, 6-triscumylphenol will be increased.
In a preferred embodiment, the temperature of the reaction is preferably from 90 to 100 ℃. If the reaction temperature is too low, the conversion of phenol is incomplete; if the reaction temperature is too high, the trialkylation side reaction is excessive and the proportion of 2,4, 6-triscumylphenol increases significantly.
In a preferred embodiment, the reaction time is preferably from 0.5 to 1h. If the reaction time is too short, the conversion of phenol is incomplete and the amount of monoalkylated product is large, and if the reaction time is too long, the amount of trialkylated product tends to increase.
In a preferred embodiment, the base is selected from at least one of sodium hydroxide, potassium hydroxide, sodium carbonate, potassium carbonate, sodium bicarbonate, potassium bicarbonate, sodium acetate. The inorganic base is preferably used in the form of an aqueous solution, and the organic base may be used in the form of an aqueous solution or directly. Preferably, a small amount of salt such as sodium salt, potassium salt (such as sodium chloride, potassium chloride) or the like may be added after neutralization to aid in the extraction delamination.
In a preferred embodiment, the organic solvent is selected from toluene, ethyl acetate, methylene chloride, chloroform, preferably toluene.
In a preferred embodiment, the distillation is carried out under vacuum conditions of not more than 30mmHg, preferably under high vacuum conditions of not more than 5 mmHg. And (3) collecting fractions at 185-190 ℃ when distilled under 5mmHg to obtain crude 2, 4-cumylphenol.
In a preferred embodiment, the recrystallization solvent is selected from petroleum ether, n-hexane, cyclohexane, and the like.
In the present invention, the inert gas includes nitrogen, argon, and the like.
In the invention, the recovered graphene oxide can be reused after being washed by ethanol and dried.
In the present invention, the recovered organic solvent can be reused for extraction.
Advantageous effects
The invention provides a method for synthesizing 2, 4-dicumyl phenol. According to the method for synthesizing the 2, 4-dicumylphenol, on the basis of a conventional acid catalyst, graphene oxide is introduced as a cocatalyst, so that the activity of a catalytic system can be increased, the phenol conversion and the further alkylation of the 4-cumylphenol can be enhanced, and the occurrence of phenol trialkylation can be restrained by a flaky plane structure, so that the selectivity of the 2, 4-cumylphenol can be improved. The graphene oxide can be repeatedly utilized for multiple times, and has high catalytic activity after repeated application. The method has the advantages of simple operation, high product yield and purity, and high practical value.
Detailed Description
The following description of embodiments of the present invention will be made clearly and fully with reference to the accompanying drawings, in which it is shown, however, only some, but not all embodiments of the invention are shown. All other embodiments, which can be made by a person skilled in the art without making any inventive effort, are intended to fall within the scope of the present invention.
The experimental methods in the following examples are conventional methods unless otherwise specified. The specific techniques or conditions are not identified in the examples and are described in the literature in this field or are carried out in accordance with the product specifications.
Preparation example 1:
taking 300ml of concentrated sulfuric acid, adding 50g of natural crystalline flake graphite and 25g of potassium permanganate while stirring, intercalating for 3 hours at room temperature to obtain intercalated graphite, and performing microwave expansion on the intercalated graphite at 800W for 30 seconds to obtain expanded graphite; mixing the obtained expanded graphite with 500ml of concentrated sulfuric acid and 100g of potassium permanganate, heating the mixed solution to 40-45 ℃ for oxidation for 2h, and fully washing the solid with 5% hydrochloric acid, absolute ethyl alcohol and deionized water until no SO exists in the filtrate 4 2- 47.9g of graphene oxide was obtained by drying.
Example 1:
under the protection of nitrogen, 100g (1.06 mol) of melted phenol, 3.65g (21 mmol,0.02 equiv) of p-toluenesulfonic acid and 1.2g of graphene oxide are added into a reactor, the mixture is heated to 60-70 ℃ after being uniformly stirred, 250g (2.12 mol,2 equiv) of alpha-methyl styrene is slowly added dropwise, and the system temperature is controlled at 90-100 ℃; after 2 hours, continuously stirring and reacting for 0.5-1 hour at the temperature after the dripping is finished, monitoring the reaction by adopting high performance liquid chromatography, wherein the alpha-methylstyrene and the phenol are completely converted, and the mass percentage of each substituted phenol in the reaction liquid is 93.2 percent of 2, 4-dicumylphenol, 6.0 percent of 4-cumylphenol and 0.8 percent of 2,4, 6-tricumylphenol. Cooling to 60-70 ℃ after the reaction is finished, filtering to recover graphene oxide, flushing with toluene, and dripping 5wt% of NaHCO into the reaction solution 3 The solution is regulated to be alkaline, then a small amount of 10wt% NaCl solution is added, toluene is used for extraction for 3 times, an organic phase is combined, water washing and anhydrous magnesium sulfate are used for drying, after the toluene is distilled and recovered, fractions with different boiling ranges are collected under high vacuum of about 5mmHg, wherein the low boiling point before 170 ℃ is mainly 4-cumylphenol, the fraction at 185-190 ℃ is crude 2, 4-cumylphenol, and the remainder is 2,4, 6-tricumylphenol and other impurities. Recrystallizing the crude 2, 4-cumylphenol with petroleum ether to obtain 309.4g of white needle-like crystal 2, 4-cumylphenol with 88.4% yield and 99.4% HPLC purity, and determining melting range of the product to 65 by digital micro-melting point tester.4～66.5℃，ESI-MS：331.2[M+H] + 。
Example 2:
under the protection of nitrogen, 100g (1.06 mol) of melted phenol, 3.65g (21 mmol,0.02 equiv) of p-toluenesulfonic acid and 1.2g of graphene oxide are added into a reactor, the mixture is heated to 60-70 ℃ after being uniformly stirred, 256.8g (2.17 mol,2.05 equiv) of alpha-methylstyrene is slowly added dropwise, and the system temperature is controlled at 90-100 ℃; after 2 hours, continuously stirring and reacting for 0.5-1 hour at the temperature after the dripping is finished, monitoring the reaction by adopting high performance liquid chromatography, wherein the alpha-methylstyrene and the phenol are completely converted, and the mass percentage of each substituted phenol in the reaction liquid is 94.3 percent of 2, 4-dicumylphenol, 4.6 percent of 4-cumylphenol and 1.1 percent of 2,4, 6-tricumylphenol. Cooling to 60-70 ℃ after the reaction is finished, filtering to recover graphene oxide, flushing with toluene, and dripping 5wt% of NaHCO into the reaction solution 3 The solution is regulated to be alkaline, then a small amount of 10wt% NaCl solution is added, toluene is used for extraction for 3 times, an organic phase is combined, water washing and anhydrous magnesium sulfate are used for drying, after the toluene is distilled and recovered, fractions with different boiling ranges are collected under high vacuum of about 5mmHg, wherein the low boiling point before 170 ℃ is mainly 4-cumylphenol, the fraction at 185-190 ℃ is crude 2, 4-cumylphenol, and the remainder is 2,4, 6-tricumylphenol and other impurities. Recrystallizing the crude 2, 4-cumylphenol with petroleum ether to obtain 312.1g of white needle-like crystal 2, 4-cumylphenol with 89.1% yield and 99.3% HPLC purity, and measuring the melting range of the product at 65.3-66.5 ℃ by a digital micro-melting point tester.
Example 3:
the reaction solution after 5 times of application of the graphene oxide was analyzed in the same manner as in example 1, using the recovered, washed and dried graphene oxide, wherein the mass percentage of each substituted phenol was 91.3% of 2, 4-dicumylphenol, 7.7% of 4-cumylphenol, and 1.0% of 2,4, 6-tricumylphenol.
Comparative example 1:
under the protection of nitrogen, 100g (1.06 mol) of melted phenol and 5.47g (3.18 mmol,0.03 equiv) of p-toluenesulfonic acid are added into a reactor, the mixture is heated to 60-70 ℃ after being stirred uniformly, 250g (2.12 mol,2 equiv) of alpha-methylstyrene is slowly added dropwise, and the temperature of the system is controlled at 95-100 ℃; after the dripping is finished in 2 hours, stirring and reacting for 2-3 hours at the temperature after the dripping is finished, and monitoring the reaction until the phenol is basically unchanged by adopting high performance liquid chromatography, wherein the mass percentages of phenol and substituted phenol in the reaction liquid are 4.3% of phenol, 76.5% of 2, 4-dicumylphenol, 16.4% of 4-cumylphenol and 2.8% of 2,4, 6-tricumylphenol.
The foregoing describes preferred embodiments of the present invention, but is not intended to limit the invention thereto. Modifications and variations to the embodiments disclosed herein may be made by those skilled in the art without departing from the scope and spirit of the invention.

Claims (14)

1. A method for synthesizing 2, 4-dicumyl phenol comprises the following steps:
under the protection of inert gas, adding molten phenol, an acid catalyst and graphene oxide into a reactor, uniformly stirring, heating to 50-80 ℃, slowly dropwise adding alpha-methyl styrene, and controlling the system temperature to 80-120 ℃; after the dripping is finished, reacting for 10 min-2 h at the temperature to obtain 2, 4-dicumyl phenol;
wherein the acid catalyst is p-toluenesulfonic acid;
the graphene oxide is prepared by the following method:
dispersing flake graphite in concentrated sulfuric acid, adding potassium permanganate, intercalating at normal temperature to obtain intercalated graphite, performing microwave expansion on the intercalated graphite to obtain expanded graphite, mixing the expanded graphite with the concentrated sulfuric acid and the potassium permanganate, oxidizing at 35-50 ℃, washing and drying the solid to obtain graphene oxide.
2. The synthesis method according to claim 1, further comprising cooling to 50-75 ℃ after the reaction is finished, filtering to recover graphene oxide, adding alkali into the reaction solution for neutralization, extracting with an organic solvent, washing an organic phase, drying, removing the solvent, distilling residues to obtain crude 2, 4-cumylphenol, and recrystallizing to obtain a 2, 4-cumylphenol product.
3. The method of claim 1, wherein the acidic catalyst is used in an amount of 1 to 5% by mole based on phenol.
4. The method of claim 1, wherein the acidic catalyst is used in an amount of 2 to 3% by mole based on phenol.
5. The synthesis method according to claim 1, wherein the amount of graphene oxide is 0.2 to 3% of the mass of phenol.
6. The synthesis method according to claim 1, wherein the amount of graphene oxide is 0.5 to 1.5% of the mass of phenol.
7. The method of claim 1, wherein the amount of α -methylstyrene is from 2 to 2.2 times the molar amount of phenol.
8. The method of claim 1, wherein the amount of α -methylstyrene is 2 to 2.1 times the molar amount of phenol.
9. The synthetic method according to claim 1, wherein the temperature of the reaction is 90 to 100 ℃; the reaction time is 0.5-1 h.
10. The synthetic method according to claim 2, wherein the organic solvent is selected from toluene, ethyl acetate, methylene chloride, chloroform.
11. The synthetic method according to claim 2, wherein the distillation is performed under vacuum of not more than 30 mmHg.
12. The synthetic method according to claim 2, wherein the distillation is performed under vacuum of not more than 5 mmHg.
13. The method of synthesis according to claim 2, wherein the recrystallization solvent is selected from petroleum ether, n-hexane, cyclohexane.
14. The synthetic method of claim 2 wherein the organic solvent is toluene.
CN202310233055.6A 2023-03-13 2023-03-13 Synthesis method of 2, 4-dicumyl phenol Active CN116283504B (en)

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Citations (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN1509265A (en) * 2001-05-16 2004-06-30 ͨ�õ�����˾ Method for preparation of cumylphenol
CN1962591A (en) * 2005-11-11 2007-05-16 中国石油化工股份有限公司 2,4-di-(1-phenylisopropyl) phenol preparation method
CN102336633A (en) * 2011-07-27 2012-02-01 哈尔滨理工大学 Preparation method of 2,4-dicumyl phenol
CN106631704A (en) * 2016-08-22 2017-05-10 江苏飞亚化学工业有限责任公司 Preparation method for styrenated phenol
CN115636731A (en) * 2022-10-14 2023-01-24 宿迁联盛科技股份有限公司 Synthesis method of 2, 4-dicumylphenol

Patent Citations (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN1509265A (en) * 2001-05-16 2004-06-30 ͨ�õ�����˾ Method for preparation of cumylphenol
CN1962591A (en) * 2005-11-11 2007-05-16 中国石油化工股份有限公司 2,4-di-(1-phenylisopropyl) phenol preparation method
CN102336633A (en) * 2011-07-27 2012-02-01 哈尔滨理工大学 Preparation method of 2,4-dicumyl phenol
CN106631704A (en) * 2016-08-22 2017-05-10 江苏飞亚化学工业有限责任公司 Preparation method for styrenated phenol
CN115636731A (en) * 2022-10-14 2023-01-24 宿迁联盛科技股份有限公司 Synthesis method of 2, 4-dicumylphenol

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