CN112321396B - Method for synthesizing hydroquinone through selective oxidation reduction of phenol - Google Patents
Method for synthesizing hydroquinone through selective oxidation reduction of phenol Download PDFInfo
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- CN112321396B CN112321396B CN202011208681.2A CN202011208681A CN112321396B CN 112321396 B CN112321396 B CN 112321396B CN 202011208681 A CN202011208681 A CN 202011208681A CN 112321396 B CN112321396 B CN 112321396B
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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
- C07C37/06—Preparation of compounds having hydroxy or O-metal groups bound to a carbon atom of a six-membered aromatic ring by conversion of non-aromatic six-membered rings or of such rings formed in situ into aromatic six-membered rings, e.g. by dehydrogenation
- C07C37/07—Preparation of compounds having hydroxy or O-metal groups bound to a carbon atom of a six-membered aromatic ring by conversion of non-aromatic six-membered rings or of such rings formed in situ into aromatic six-membered rings, e.g. by dehydrogenation with simultaneous reduction of C=O group in that ring
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- 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
- B01J31/0272—Catalysts comprising hydrides, coordination complexes or organic compounds containing organic compounds or metal hydrides containing elements other than those covered by B01J31/0201 - B01J31/0255
- B01J31/0275—Catalysts comprising hydrides, coordination complexes or organic compounds containing organic compounds or metal hydrides containing elements other than those covered by B01J31/0201 - B01J31/0255 also containing elements or functional groups covered by B01J31/0201 - B01J31/0269
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- C—CHEMISTRY; METALLURGY
- C07—ORGANIC CHEMISTRY
- C07C—ACYCLIC OR CARBOCYCLIC COMPOUNDS
- C07C46/00—Preparation of quinones
- C07C46/02—Preparation of quinones by oxidation giving rise to quinoid structures
- C07C46/06—Preparation of quinones by oxidation giving rise to quinoid structures of at least one hydroxy group on a six-membered aromatic ring
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- 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
- B01J2231/70—Oxidation reactions, e.g. epoxidation, (di)hydroxylation, dehydrogenation and analogues
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- 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
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- 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
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Abstract
The scheme relates to a method for synthesizing hydroquinone by phenol selective oxidation reduction, which comprises the following steps: adding an organic selenium catalyst containing carbon nano tubes, phenol and 30% hydrogen peroxide into a reaction bottle, adding DMF, uniformly stirring, charging nitrogen, sealing, reacting at 60 ℃ for 1-2h, filtering, collecting filtrate and solid, removing DMF from the filtrate by rotary evaporation, adding ethanol for dilution, adding triisooctylamine, stirring to separate p-benzoquinone from the ethanol, and collecting the p-benzoquinone; adding a metal catalyst and pyridine into a reaction bottle, adding the p-benzoquinone into the reaction bottle, adding a hydrogen donor, and heating the mixture for reaction for 1-2 hours; and concentrating, decoking, decoloring and crystallizing the reaction solution to obtain hydroquinone. The invention starts from phenol, utilizes the self-made organic selenium catalyst to prepare p-benzoquinone with high selectivity, and then reduces p-benzoquinone into p-dihydroxybenzene through Pt/C catalytic hydrogenation, and can achieve higher selectivity at medium and high temperature, and simultaneously achieve nearly complete conversion of the p-benzoquinone.
Description
Technical Field
The invention relates to the technical field of hydroquinone synthesis, in particular to a method for synthesizing hydroquinone by selective oxidation reduction of phenol.
Background
Phenol is a common basic chemical raw material, has large yield and low price, and p-benzoquinone is an intermediate for synthesizing hydroquinone. The selective oxidation of p-benzoquinone is crucial when synthesizing Hydroquinone from phenol, and Hydroquinone (HQ) is also called Hydroquinone, which is an important industrial intermediate. Antioxidants, which are widely used in the preparation of electrode materials, photographic developers, anthraquinone and azo dyes, rubber and gasoline, are raw materials for the manufacture of dyes and pharmaceutical compounds, as well as basic raw materials for the preparation of bioactive natural products and functional materials such as polymer liquid crystals and other polymers.
At present, the most primitive route to hydroquinone is through MnO2And H2SO4Oxidizing aniline with water solution to form benzoquinone, and reducing the benzoquinone through iron powder or hydrogenation to obtain hydroquinone product. However, this approach inevitably results in the production of large quantities of solid waste which is difficult to dispose of, or the use of flammable and explosive gases such as hydrogen which is potentially dangerous.
Disclosure of Invention
Aiming at the defects in the prior art, the invention aims to provide a synthesis method for high-selectivity oxidation reduction of phenol into hydroquinone.
In order to achieve the purpose, the invention provides the following technical scheme:
a method for synthesizing hydroquinone by phenol selective oxidation reduction comprises the following steps:
s1: adding organic selenium catalyst containing carbon nano tube, phenol and 30% hydrogen peroxide into a reaction bottle, adding N, N-dimethylformamide, stirring uniformly, charging nitrogen, sealing, and reacting for 1-2h at 60 ℃;
s2: filtering and collecting filtrate and solid after the reaction is finished, removing N, N-dimethylformamide from the filtrate through rotary evaporation, adding ethanol for dilution, then adding triisooctylamine for stirring to separate the p-benzoquinone from the ethanol, and collecting the p-benzoquinone;
s3: adding a metal catalyst and pyridine into a round-bottom flask, adding the p-benzoquinone into the flask, adding a hydrogen donor, and heating the mixture at 80-100 ℃ for 1-2 hours;
s4: after the reaction is finished, the reaction solution is concentrated, decoked, decolored and crystallized to obtain the hydroquinone.
Further, the organic selenium catalyst containing the carbon nano tube accounts for 0.5-5wt% of the mass of the phenol, and the molar ratio of the hydrogen peroxide to the phenol is 1-3: 1.
Further, the preparation method of the organic selenium catalyst containing carbon nano tubes comprises the following steps:
1) adding selenium powder into distilled water, introducing nitrogen gas, stirring, adding sodium borohydride water solution, adding equal amount of selenium powder, heating to 50-60 deg.C, and reacting for 40-60 min;
2) dropwise adding saturated sodium carbonate solution into an aqueous solution of 4-bromo-2, 6-difluorobenzoic acid, and adjusting the pH to 9-10;
3) dropwise adding the alkaline solution obtained in the step 2) into the step 1), and stirring at room temperature for reaction for 24 hours;
4) filtering after the reaction is finished, adjusting the pH of the filtrate to 3-4 by using dilute hydrochloric acid, performing suction filtration, washing with water, drying, and recrystallizing by using ethyl acetate to obtain the carboxylic acid diselenide;
5) and (2) placing the modified carbon nano tube in a solvent, adding the carboxylic diselenide, stirring and refluxing for 12-24h at 70-80 ℃, filtering, washing and drying to obtain the organic selenium catalyst containing the carbon nano tube.
Further, the molar ratio of the selenium powder to the sodium borohydride and the halogenated carboxylic acid is 1:1: 1.
Further, the modified carbon nanotube is a hydroxylated double-wall carbon nanotube, and the mass ratio of the modified carbon nanotube to the carboxylic acid diselenide is 1: 5-10.
Further, the metal catalyst is selected from one of a platinum catalyst, a copper catalyst, a nickel catalyst or a palladium catalyst.
Further, the hydrogen donor is selected from one of cyclohexanone, isopropanol, isooctanol or cyclohexanol.
Furthermore, the molar ratio of the p-benzoquinone to the hydrogen donor and the pyridine is 1: 5-10: 1% -5%.
The invention has the beneficial effects that: the invention starts from phenol, and the phenol has large yield and low price; the p-benzoquinone is prepared by utilizing the self-made organic selenium catalyst in a high-selectivity manner, the organic selenium catalyst is simple to prepare and low in dosage, and can rapidly catalyze phenol to synthesize the p-benzoquinone under mild conditions; then p-benzoquinone is hydrogenated and reduced to p-dihydroxybenzene by Pt/C catalysis, high selectivity can be achieved at medium and high temperature, and conversion of p-benzoquinone can be almost complete.
Detailed Description
The technical solutions of the present invention will be described clearly and completely with reference to the following embodiments, and it should be understood that the described embodiments are some, but not all, embodiments of the present invention. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present invention.
In addition, the technical features involved in the different embodiments of the present invention described below may be combined with each other as long as they do not conflict with each other.
A method for synthesizing hydroquinone by phenol selective oxidation reduction comprises the following steps:
s1: adding an organic selenium catalyst containing carbon nano tubes, phenol and 30% hydrogen peroxide into a reaction bottle, adding N, N-dimethylformamide, uniformly stirring, filling nitrogen, sealing, and reacting for 1-2h at 60 ℃;
s2: filtering and collecting filtrate and solid after the reaction is finished, removing N, N-dimethylformamide from the filtrate through rotary evaporation, adding ethanol for dilution, then adding triisooctylamine for stirring, wherein the phenol has weak acidity, and the combination of the phenol and p-benzoquinone is destroyed by utilizing the similar complexation force formed between the triisooctylamine and the phenol, so that the solubility of the benzoquinone in the ethanol is reduced, and the p-benzoquinone is separated out and collected;
s3: adding a metal catalyst and pyridine into a round-bottom flask, adding the p-benzoquinone into the flask, adding a hydrogen donor, and heating the mixture at 80-100 ℃ for 1-2 hours;
s4: after the reaction is finished, the reaction solution is concentrated, decoked, decolored and crystallized to obtain the hydroquinone.
Further, the organic selenium catalyst containing the carbon nano tube accounts for 0.5-5wt% of the mass of the phenol, and the molar ratio of the hydrogen peroxide to the phenol is 1-3: 1.
Further, the preparation method of the organic selenium catalyst containing the carbon nano tube comprises the following steps:
1) adding 0.8g (0.01mol) of selenium powder into distilled water, introducing nitrogen, stirring uniformly, then adding 0.75g (0.02mol) of aqueous solution of sodium borohydride, supplementing 0.8g (0.01mol) of selenium powder, heating to 50-60 ℃, and reacting for 40-60 min;
2) dropwise adding a saturated sodium carbonate solution into 10ml of 0.02mol of 4-bromo-2, 6-difluorobenzoic acid aqueous solution, and adjusting the pH to 9-10;
3) dropwise adding the alkaline solution obtained in the step 2) into the step 1), and stirring at room temperature for reaction for 24 hours;
4) filtering after the reaction is finished, adjusting the pH of the filtrate to 3-4 by using dilute hydrochloric acid, performing suction filtration, washing with water, drying, and recrystallizing by using ethyl acetate to obtain the carboxylic acid diselenide;
5) and (2) placing the modified carbon nano tube in a N, N-Dimethylformamide (DMF) solvent, adding the carboxylic diselenide, ultrasonically dispersing for 30min, stirring and refluxing for 12h at 70-80 ℃, filtering, washing and drying to obtain the organic selenium catalyst containing the carbon nano tube.
Wherein the metal catalyst is selected from one of a platinum catalyst, a copper catalyst, a nickel catalyst or a palladium catalyst.
Wherein, the hydrogen donor is selected from one of cyclohexanone, isopropanol, isooctanol or cyclohexanol.
Wherein the molar ratio of the p-benzoquinone to the hydrogen donor to the pyridine is 1: 5-10: 1% -5%.
Example (b): is prepared by the steps as described above, wherein,
the organic selenium catalyst containing the carbon nano tube can be prepared by the following steps: 1) adding 0.8g (0.01mol) of selenium powder into distilled water, introducing nitrogen, stirring uniformly, then adding 0.75g (0.02mol) of aqueous solution of sodium borohydride, supplementing 0.8g (0.01mol) of selenium powder, heating to 50-60 ℃, and reacting for 40-60 min; 2) dropwise adding a saturated sodium carbonate solution into 10ml of 0.02mol of 4-bromo-2, 6-difluorobenzoic acid aqueous solution, and adjusting the pH to 9-10; 3) dropwise adding the alkaline solution obtained in the step 2) into the step 1), and stirring at room temperature for reaction for 24 hours; 4) filtering after the reaction is finished, adjusting the pH of the filtrate to 3-4 by using dilute hydrochloric acid, performing suction filtration, washing with water, drying, and recrystallizing by using ethyl acetate to obtain the carboxylic acid diselenide; 5) and (2) putting the modified carbon nano tube into an N, N-Dimethylformamide (DMF) solvent, adding the carboxylic diselenide, performing ultrasonic dispersion for 30min, stirring and refluxing for 12h at 70-80 ℃, filtering, washing and drying to obtain the organic selenium catalyst containing the carbon nano tube.
The p-benzoquinone can be prepared by the following steps: adding 0.47mg of organic selenium catalyst containing carbon nano tubes, 0.47g of phenol and 0.56g of 30% hydrogen peroxide into a reaction bottle, adding 10ml of DMF, uniformly stirring, filling nitrogen, sealing and reacting for 2 hours at 60 ℃; after the reaction is finished, the reaction solution is concentrated, decoked, decolored and crystallized to obtain the hydroquinone.
Example 1: 540mg of platinum catalyst and 0.8mmol of pyridine are added into a round-bottom flask, 50mmol of p-benzoquinone is added into the flask, 300mmol of cyclohexanone is added, and the mixture is heated for 2 hours at 80 ℃; after the reaction is finished, the reaction solution is concentrated, decoked, decolored and crystallized to obtain the hydroquinone.
Example 2: 540mg of copper catalyst and 1.2mmol of pyridine are added into a round-bottom flask, 50mmol of p-benzoquinone is added into the flask, 350mmol of isopropanol is added, and the mixture is heated for 2 hours at 80 ℃; after the reaction is finished, the reaction solution is concentrated, decoked, decolored and crystallized to obtain the hydroquinone.
Example 3: 540mg of nickel catalyst and 1.30mmol of pyridine are added into a round-bottom flask, 50mmol of p-benzoquinone is added into the flask, 300mmol of isooctyl alcohol is added, and the mixture is heated for 2 hours at 80 ℃; after the reaction is finished, the reaction solution is concentrated, decoked, decolored and crystallized to obtain the hydroquinone.
Example 4: 540mg of platinum catalyst and 1.65mmol of pyridine are added into a round-bottom flask, 50mmol of p-benzoquinone is added into the flask, 450mmol of cyclohexanone is added, and the mixture is heated for 2 hours at 80 ℃; after the reaction is finished, the reaction solution is concentrated, decoked, decolored and crystallized to obtain hydroquinone.
Example 5: 540mg of platinum catalyst and 3.0mmol of pyridine are added into a round-bottom flask, 50mmol of p-benzoquinone is added into the flask, 500mmol of cyclohexanone is added, and the mixture is heated for 2 hours at 80 ℃; after the reaction is finished, the reaction solution is concentrated, decoked, decolored and crystallized to obtain the hydroquinone.
As can be seen from the data in Table 1, the conversion and selectivity of comparative examples 1-3, example 1 (with platinum catalyst and cyclohexanone as hydrogen donor) are better than those of examples 2 and 3, and on the basis of example 1, the amount of pyridine and cyclohexanone is increased, and the amount of example 4 can reach the best quality value of the scheme, and when the amount is increased again, the conversion and selectivity are not obviously promoted.
TABLE 1
While embodiments of the invention have been disclosed above, it is not limited to the applications listed in the description and the embodiments, which are fully applicable in all kinds of fields of application of the invention, and further modifications may readily be effected by those skilled in the art, so that the invention is not limited to the specific details without departing from the general concept defined by the claims and the scope of equivalents.
Claims (7)
1. The method for synthesizing hydroquinone through phenol selective oxidation reduction is characterized by comprising the following steps:
s1: adding organic selenium catalyst containing carbon nano tube, phenol and 30% hydrogen peroxide into a reaction bottle, adding N, N-dimethylformamide, stirring uniformly, charging nitrogen, sealing, and reacting for 1-2h at 60 ℃;
s2: filtering and collecting filtrate and solid after the reaction is finished, removing N, N-dimethylformamide from the filtrate through rotary evaporation, adding ethanol for dilution, then adding triisooctylamine for stirring to separate the p-benzoquinone from the ethanol, and collecting the p-benzoquinone;
s3: adding a metal catalyst and pyridine into a round-bottom flask, adding the p-benzoquinone into the flask, adding a hydrogen donor, and heating the mixture at 80-100 ℃ for 1-2 hours;
s4: after the reaction is finished, concentrating, decoking, decoloring and crystallizing the reaction liquid to obtain hydroquinone;
wherein, the preparation steps of the organic selenium catalyst containing the carbon nano tube are as follows:
1) adding selenium powder into distilled water, introducing nitrogen gas, stirring, adding sodium borohydride water solution, adding equal amount of selenium powder, heating to 50-60 deg.C, and reacting for 40-60 min;
2) dropwise adding saturated sodium carbonate solution into an aqueous solution of 4-bromo-2, 6-difluorobenzoic acid, and adjusting the pH to 9-10;
3) dropwise adding the alkaline solution obtained in the step 2) into the step 1), and stirring at room temperature for reaction for 24 hours;
4) filtering after the reaction is finished, adjusting the pH of the filtrate to 3-4 by using dilute hydrochloric acid, performing suction filtration, washing with water, drying, and recrystallizing by using ethyl acetate to obtain the carboxylic acid diselenide;
5) and (2) placing the modified carbon nano tube in a solvent, adding the carboxylic diselenide, stirring and refluxing for 12-24h at 70-80 ℃, filtering, washing and drying to obtain the organic selenium catalyst containing the carbon nano tube.
2. The method for synthesizing hydroquinone through selective oxidation-reduction of phenol according to claim 1, wherein the organic selenium catalyst containing carbon nano tubes accounts for 0.5-5wt% of the mass of phenol, and the molar ratio of hydrogen peroxide to phenol is 1-3: 1.
3. The method for selective oxidation-reduction synthesis of hydroquinone with phenol according to claim 1, characterized in that the molar ratio of selenium powder to sodium borohydride and halogenated carboxylic acid is 1:1: 1.
4. The method for synthesizing hydroquinone through phenol selective oxidation-reduction according to claim 1, wherein the modified carbon nanotubes are hydroxylated double-wall carbon nanotubes, and the mass ratio of the modified carbon nanotubes to the carboxylic diselenide is 1: 5-10.
5. The method for selective redox synthesis of hydroquinone with phenol according to claim 1, characterized in that the metal catalyst is selected from one of platinum catalyst, copper catalyst, nickel catalyst or palladium catalyst.
6. The phenol selective redox synthesis process for hydroquinone in accordance with claim 1, wherein the hydrogen donor is selected from one of cyclohexanone, isopropanol, isooctanol or cyclohexanol.
7. The method for selective oxidation-reduction synthesis of hydroquinone with phenol according to claim 1, wherein the molar ratio of p-benzoquinone to hydrogen donor and pyridine is 1: 5-10: 1-5%.
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| 有机硒催化苯酚选择性氧化制对苯醌的研究;王芳 等;《有机化学》;20170427;2115-2118 * |
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