CN111635287A - Synthesis method of substituted phenol - Google Patents
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- CN111635287A CN111635287A CN202010425337.2A CN202010425337A CN111635287A CN 111635287 A CN111635287 A CN 111635287A CN 202010425337 A CN202010425337 A CN 202010425337A CN 111635287 A CN111635287 A CN 111635287A
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Abstract
The invention provides a method for synthesizing substituted phenol, which prepares a target product substituted phenol by using substituted benzene as a starting material, and has the advantages of high selectivity, high yield, convenient operation and high atom economy in the whole synthesis process.
Description
Technical Field
The invention relates to the technical field of organic synthesis, in particular to a synthesis method of substituted phenol.
Background
The phenol derivative containing the substituent group is an important chemical intermediate and has important application in the fields of medicine, agriculture and high polymer. For example, ortho-cresol, meta-cresol and para-cresol, which have the simplest structures, can be used for synthesis of synthetic resins, intermediates of pesticides, herbicides, and the like, respectively; 4-nonyl phenol is used for synthesizing detergents, moisturizers, lubricating oil additives, plasticizers and the like; 5', 5-diallyl-2, 2' -biphenol (magnolol) is used in medicine as antifungal agent; 4, 5-diacetylene-2-methoxyphenol is one of the key raw materials for preparing the asymmetric dendritic resin with optical performance.
At present, there are two main methods for industrially producing corresponding phenol by using aromatic hydrocarbon as a raw material: the method has the disadvantages of multiple reaction steps, long route, complex operation process, serious corrosion to reaction equipment, higher cost, large amount of three wastes and serious environmental pollution, and belongs to a rejected process; although the method has high reaction atom economy, less three wastes and low cost, the byproduct acetone has no good economic benefit, the acetone production capacity is surplus at present in China and even in the whole world, the acetone is a raw material for preparing the virus, and the byproduct acetone is difficult to produce and has a value.
Conventional methods for synthesizing polysubstituted phenols also include oxidation of benzyl alcohol, hydrolysis of halogenated aromatics, Fries rearrangement of esters, demethylation of anisole compounds, etc., but these methods often suffer from one or more disadvantages such as low yield, poor selectivity, etc.
Disclosure of Invention
Based on the technical problems in the background art, the invention provides a method for synthesizing substituted phenol, which prepares the target product substituted phenol by using substituted benzene as a starting material, and has the advantages of high selectivity, high yield, convenient operation and high atom economy in the whole synthesis process.
The invention provides a method for synthesizing substituted phenol, which comprises the following steps:
(1) carrying out Friedel-crafts alkylation reaction on substituted benzene shown in a formula I to obtain cyclopentyl benzene containing a substituent group or cyclohexyl benzene containing a substituent group shown in a formula II;
(2) performing oxidation reaction on the substituted cyclopentyl benzene or the substituted cyclohexyl benzene shown in the formula II to obtain substituted phenyl cyclopentyl hydroperoxide or substituted phenyl cyclohexyl hydroperoxide shown in the formula III;
(3) carrying out cracking reaction on phenyl cyclopentyl hydroperoxide containing substituent groups or phenyl cyclohexyl hydroperoxide containing substituent groups shown in a formula III to obtain substituted phenol;
in the formulas I, II and III, R is one or more substituent groups at any possible position on a benzene ring.
Preferably, the substituted benzene shown in the formula I and an alkylating agent are subjected to Friedel-crafts alkylation reaction under the condition of a first catalyst to obtain the substituted cyclopentyl benzene or substituted cyclohexyl benzene shown in the formula II.
Preferably, the alkylating agent is cyclopentene, cyclohexene or halogenated cyclopentane, halogenated cyclohexane or cyclopentanol, cyclohexanol; preferably, the halogenated cyclopentane is chloro-cyclopentane or bromo-cyclopentane, and the halogenated cyclohexane is chloro-cyclohexane or bromo-cyclohexane.
In the step, substituted cyclopentyl benzene or substituted cyclohexyl benzene can be prepared by Friedel-crafts alkylation reaction of mono-substituted benzene or poly-substituted benzene and cyclopentene or cyclohexene; or the substituted cyclopentyl benzene or the substituted cyclohexyl benzene is prepared by the Friedel-crafts alkylation reaction of the mono-substituted benzene or the poly-substituted benzene and the halogenated cyclopentane or the halogenated cyclohexane; it is even possible to prepare substituted cyclopentylbenzenes or substituted cyclohexylbenzenes by Friedel-crafts alkylation of mono-or poly-substituted benzenes with cyclopentanol or cyclohexanol.
The mono-substituted benzene or poly-substituted benzene can be any of the following structures:
monosubstituted benzenes
Disubstituted benzenes
Trisubstituted benzenes
Tetra-substituted benzene
Penta-substituted benzene
R1、R2、R3、R4Or R5Respectively selected from alkyl, alkoxy, alkoxyalkyl, alkylamino, dialkylamino, amido, acyloxy, halogen, phenyl, substituted phenyl, fused ring aryl, substituted fused ring aryl, heterocyclic aryl or substituted heterocyclic aryl;
the substituent in the substituted phenyl, the substituted condensed ring aromatic group and the substituted heterocyclic aromatic group can be nitro, trihalomethyl, acyl, formyl, cyano, sulfonic group or carboxyl;
R1、R2、R3、R4or R5Each independently may be the same or different.
Preferably, the first catalyst is a compound ionic liquid or a molecular sieve catalyst prepared from Lewis acid, protonic acid, Lewis acid and triethylamine hydrochloride ionic liquid; preferably, the first catalyst is aluminum trichloride AlCl3FeCl, ferric chloride3Titanium tetrachloride TiCl4ZnCl, zinc chloride2SnCl, tin chloride2Boron trifluoride BF3Sulfuric acid H2SO4Phosphoric acid H3PO4HF, triethylamine hydrochloride-aluminium trichloride Et3NHCl-AlCl3The composite ionic liquid and the MCM-22 molecular sieve.
The temperature of the Friedel-crafts alkylation reaction is-10 to 60 ℃, and the reaction time is 1 to 24 hours.
Preferably, in the step (2), the substituted cyclopentyl-benzene or substituted cyclohexyl-benzene shown in the formula II is subjected to oxidation reaction with an oxidant under the condition of a second catalyst to obtain substituted phenyl-cyclopentyl-hydroperoxide or substituted phenyl-cyclohexyl-hydroperoxide shown in the formula III.
Preferably, the oxidant is air or oxygen;
the second catalyst is one or the combination of more of 2, 2, 6, 6-tetramethyl piperidine nitroxide free radical and derivatives thereof, N-hydroxyl substituted cyclic imide compounds and sodium carbonate;
wherein, the 2, 2, 6, 6-tetramethyl piperidine nitroxide free radical and the derivatives thereof are selected from one or more compounds with the following structures:
the N-hydroxy substituted cyclic imide compound is selected from one or more of N-hydroxyphthalimide, 4-amino-N-hydroxyphthalimide, 3-amino-N-hydroxyphthalimide, N-hydroxyphenetetrachlorophthalimide, N-hydroxytetrabromophthalimide, N-hydroxytoluenetriomide, N-hydroxyphenyl-1, 2, 4-trimethylimide, pyridine-2, 3-dicarboximide, N-hydroxysuccinimide or N-hydroxy (tartrimide).
In the step, the substituted cyclopentyl benzene or the substituted cyclohexyl benzene is oxidized by air or oxygen to obtain the substituted phenyl cyclopentyl hydroperoxide or the substituted phenyl cyclohexyl hydroperoxide, and the oxidant in the reaction is only oxygen or oxygen in the air, so that the cost is effectively reduced.
Preferably, the temperature of the oxidation reaction is 0-120 ℃.
Preferably, in the step (3), the substituted phenyl cyclopentyl hydroperoxide or substituted phenyl cyclohexyl hydroperoxide shown in the formula III is subjected to a cracking reaction under the condition of an acid catalyst to obtain the substituted phenol.
Preferably, the acid catalyst is one or a combination of more of perchloric acid, sulfuric acid, phosphoric acid or p-toluenesulfonic acid.
In the step, phenyl cyclopentyl hydroperoxide containing substituent groups or phenyl cyclohexyl hydroperoxide containing substituent groups is decomposed under the condition of acid catalyst to obtain the target product substituted phenol, and the reaction by-product cyclopentanone or cyclohexanone in the step is a very widely applied and very important chemical raw material, so the synthetic route has very high economic benefit.
Preferably, the temperature of the cleavage reaction is 0-60 ℃.
The synthesis method of the substituted phenol can be represented by the following reaction scheme:
the invention completely new uses substituted benzene as raw material to synthesize substituted phenol by three steps, the raw material is simple and easy to obtain, the reaction process is safe and environment-friendly, the three wastes are less, the reaction atom economy is high, the byproduct economic value is high, and the invention is very suitable for industrialized production.
Drawings
FIG. 1 is a nuclear magnetic hydrogen spectrum of 4-phenylphenol;
FIG. 2 is a nuclear magnetic hydrogen spectrum of 2-methyl-5-fluorophenol;
FIG. 3 is a nuclear magnetic hydrogen spectrum of 2, 4, 6-trimethylphenol;
FIG. 4 is a nuclear magnetic hydrogen spectrum of 4-dimethylaminophenol;
Detailed Description
For the purpose of facilitating an understanding of the present invention, the present invention will now be described by way of examples. It should be understood by those skilled in the art that the examples are only for the understanding of the present invention and should not be construed as the specific limitations of the present invention.
Example 1
A method for synthesizing 4-phenylphenol, wherein the structural formula of the 4-phenylphenol is as follows:
the method specifically comprises the following steps:
(1) putting anhydrous aluminum trichloride (4g, 0.03mol) into a dry 1000mL three-neck flask, adding biphenyl (462.6g, 3mol) and 1, 2-dichloroethane (800mL), stirring to completely dissolve the biphenyl, slowly dropwise adding cyclopentene (40.87g, 0.6mol) under the stirring condition, controlling the reaction temperature at 0 ℃, continuously stirring at the temperature for 24 hours after dropwise adding is finished, pouring the reaction system into a separating funnel, washing with 100mL of water for 3 times, carrying out reduced pressure distillation on an organic phase, recovering a solvent and redundant biphenyl to obtain a crude product 114g, wherein the content of 4-cyclopentyl biphenyl is 83%;
(2) adding the crude 4-cyclopentylbiphenyl product (80.4g, 0.3mol) obtained in the step (1) and acetonitrile (200mL) into a 500mL three-neck flask, stirring and dissolving, then adding N-hydroxyphthalimide (0.49g, 0.003mol) and peracetic acid (0.23g, 0.003mol), controlling the temperature at 0 ℃, starting introducing air, stirring and reacting for 24 hours, carrying out reduced pressure distillation to recover acetonitrile, cooling to room temperature, adding cyclopentanone (200mL) into the residue, adding 1 wt% sodium hydroxide aqueous solution (25g), stirring for 1 hour, standing and demixing to obtain an organic phase;
(3) transferring the organic phase obtained in the step (2) into a 500mL three-neck flask, adding 98 wt% concentrated sulfuric acid (0.3g, 0.003mol), stirring and reacting at 0 ℃ for 10 hours, neutralizing the pH of the system to 6-7 with saturated sodium bicarbonate after the reaction is finished, standing and layering, carrying out vacuum distillation on the organic phase to recover the solvent, recrystallizing the residue with ethanol, and drying to obtain 33.2g of a white-like crystal with the content of 4-phenylphenol of 99%, wherein the hydrogen spectrum of 4-phenylphenol is shown in figure 1.
In this embodiment, the synthesis of 4-phenylphenol can be further performed by the following method, which specifically comprises the following steps:
(1) putting anhydrous aluminum trichloride (4g, 0.03mol) into a dry 1000mL three-neck flask, adding biphenyl (462.6g, 3mol) and 1, 2-dichloroethane (800mL), stirring to completely dissolve the biphenyl, slowly dropwise adding chlorocyclopentane (62.75g, 0.6mol) under the stirring condition, controlling the reaction temperature at 0 ℃, continuously stirring at the temperature for 10 hours after dropwise adding is finished, pouring the reaction system into a separating funnel, washing with 100mL of water for 3 times, carrying out reduced pressure distillation on an organic phase, recovering the solvent and the redundant biphenyl to obtain a crude product of 120g, wherein the content of 4-cyclopentyl biphenyl is 89%;
(2) adding the crude product of 4-cyclopentylbiphenyl (75g, 0.3mol) obtained in the step (1), 2, 6, 6-tetramethylpiperidine oxide (0.47g, 0.003mol) and cyclopentanone (200mL) into a high-pressure reaction kettle, stirring and dissolving, then adding a sodium carbonate aqueous solution (100g) with the mass fraction of 5%, introducing oxygen (0.5Mpa) into the kettle, heating to 100 ℃, stirring and reacting for 15 hours, standing and layering after the reaction is finished, and keeping an organic phase;
(3) and (3) transferring the organic phase obtained in the step (2) into a 500mL three-neck flask, adding 98 wt% concentrated sulfuric acid (0.3g, 0.003mol), stirring and reacting at 0 ℃ for 10 hours, neutralizing the pH of the system to 6-7 with saturated sodium bicarbonate after the reaction is finished, standing and layering, carrying out vacuum distillation on the organic phase to recover the solvent, recrystallizing the residue with ethanol, and drying to obtain 31.6g of a white-like crystal with the content of 4-phenylphenol of 99%.
In the same example, 4-phenylphenol can also be synthesized by the following method, which specifically comprises the following steps:
(1) putting anhydrous aluminum trichloride (4g, 0.03mol) into a dry 1000mL three-neck flask, adding biphenyl (462.6g, 3mol) and 1, 2-dichloroethane (800mL), stirring to completely dissolve the biphenyl, slowly dropwise adding cyclopentanol (51.68g, 0.6mol) under the stirring condition, controlling the reaction temperature at 0 ℃, continuously stirring at the temperature for 10 hours after dropwise adding is finished, pouring the reaction system into a separating funnel, washing with 100mL of water for 3 times, carrying out reduced pressure distillation on an organic phase, recovering a solvent and redundant biphenyl, and obtaining a crude product of 110g, wherein the content of 4-cyclopentyl biphenyl is 85%;
(2) adding the crude 4-cyclopentylbiphenyl product (78.5g, 0.3mol) obtained in the step (1) and cyclopentanone (200mL) into a high-pressure reaction kettle, stirring and dissolving, then adding a sodium carbonate aqueous solution (100g) with the mass fraction of 5%, introducing oxygen (5Mpa) into the kettle, heating to 120 ℃, stirring and reacting for 10 hours, standing and layering after the reaction is finished, and keeping an organic phase;
(3) and (3) transferring the organic phase obtained in the step (2) to a 500mL three-neck flask, adding 98 wt% concentrated sulfuric acid (0.3g, 0.003mol), stirring and reacting at 0 ℃ for 10 hours, neutralizing the pH of the system to 6-7 with saturated sodium bicarbonate after the reaction is finished, standing and layering, carrying out vacuum distillation on the organic phase to recover the solvent, recrystallizing the residue with ethanol, and drying to obtain 26.7g of a white-like crystal with the content of 4-phenylphenol of 99%.
Example 2
A synthetic method of 2-methyl-5-fluorophenol is disclosed, wherein the structural formula of the 2-methyl-5-fluorophenol is as follows:
the method specifically comprises the following steps:
(1) firstly, preparing triethylamine hydrochloride-aluminum trichloride ionic liquid: under the protection of nitrogen, triethylamine hydrochloride (137.65g, 1mol) and n-heptane (200mL) are placed in a clean three-neck flask to be stirred and mixed, anhydrous aluminum trichloride (267g, 2mol) is added in batches at room temperature in the stirring process, stirring is continued for 3 hours after the addition is finished to form ionic liquid, standing and layering are carried out, the upper layer is a protective solvent n-heptane, the lower layer is the ionic liquid, and the ionic liquid is placed in a dryer to be stored;
placing the prepared ionic liquid (15g) into a dry 500mL three-neck flask under the nitrogen atmosphere, adding p-fluorotoluene (220.3g, 2mol), slowly dropwise adding cyclohexene (16.4g, 0.2mol) under the stirring condition, controlling the reaction temperature at 60 ℃, continuing to stir at the temperature for 6 hours after dropwise adding, pouring the reaction system into a separating funnel, washing with 50mL of water for 3 times, carrying out reduced pressure distillation on an organic phase, and recovering the redundant p-fluorotoluene to obtain a crude product of 30.3g, wherein the content of 1-cyclohexyl-2-methyl-5-fluorobenzene is 86%;
(2) adding propionitrile (200mL) into the 1-cyclohexyl-2-methyl-5-fluorobenzene crude product obtained in the step (1), stirring and dissolving, transferring into a 500mL three-neck flask, adding 3-amino-N-hydroxyphthalimide (0.36g, 0.002mol) and m-chloroperoxybenzoic acid (0.35g, 0.002mol), introducing oxygen at 90 ℃, stirring and reacting for 5 hours, carrying out reduced pressure distillation to recover propionitrile, cooling to room temperature, adding cyclohexanone (200mL) into a residue, adding 1 wt% of sodium hydroxide aqueous solution (16g), stirring for 1 hour, standing and layering to obtain an organic phase;
(3) transferring the organic phase obtained in the step (2) into a 500mL three-neck flask, adding p-toluenesulfonic acid (0.35g, 0.002mol), stirring and reacting at 60 ℃ for 5 hours, neutralizing the pH value of a system to be 6-7 with saturated sodium bicarbonate after the reaction is finished, standing and layering, carrying out vacuum distillation on the organic phase to obtain 16.5g of yellow liquid product, wherein the purity of 2-methyl-5-fluorophenol is 93%, the hydrogen spectrum of 2-methyl-5-fluorophenol is shown in figure 2, and the residual solvent is recovered.
In this embodiment, the synthesis of 2-methyl-5-fluorophenol can be further performed by the following method, which specifically comprises the following steps:
(1) firstly, preparing triethylamine hydrochloride-aluminum trichloride ionic liquid: under the protection of nitrogen, triethylamine hydrochloride (137.65g, 1mol) and n-heptane (200mL) are placed in a clean three-neck flask to be stirred and mixed, anhydrous aluminum trichloride (267g, 2mol) is added in batches at room temperature in the stirring process, stirring is continued for 3 hours after the addition is finished to form ionic liquid, standing and layering are carried out, the upper layer is a protective solvent n-heptane, the lower layer is the ionic liquid, and the ionic liquid is placed in a dryer to be stored;
placing the prepared ionic liquid (15g) into a dry 500mL three-neck flask under the nitrogen atmosphere, adding p-fluorotoluene (220.3g, 2mol) and 1, 2-dichloroethane (300mL), slowly dropwise adding chlorocyclohexane (29.65g, 0.25mol) under the stirring condition, controlling the reaction temperature at 40 ℃, after dropwise adding, continuing to stir at the temperature for 6 hours, pouring the reaction system into a separating funnel, washing with 50mL of water for 3 times, carrying out reduced pressure distillation on an organic phase, and recovering the solvent and the redundant p-fluorotoluene to obtain a crude product of 34.2g, wherein the content of 1-cyclohexyl-2-methyl-5-fluorobenzene is 85%;
(2) adding the 1-cyclohexyl-2-methyl-5-fluorobenzene crude product obtained in the step (1), 4-hydroxy-2, 2, 6, 6-tetramethylpiperidine oxide (0.34g, 0.002mol) and cyclohexanone (200mL) into a high-pressure reaction kettle, stirring and dissolving, then adding a sodium carbonate aqueous solution (100g) with the mass fraction of 5%, introducing oxygen (0.5Mpa) into the kettle, heating to 105 ℃, stirring and reacting for 15 hours, standing and layering after the reaction is finished, and keeping an organic phase;
(3) and (3) transferring the organic phase obtained in the step (2) to a 500mL three-neck flask, adding p-toluenesulfonic acid (0.35g, 0.002mol), stirring and reacting at 25 ℃ for 5 hours, neutralizing the pH value of a system to be 6-7 with saturated sodium bicarbonate after the reaction is finished, standing and layering, carrying out vacuum distillation on the organic phase to obtain 17.1g of yellow liquid product, wherein the purity of 2-methyl-5-fluorophenol is 90%, and recovering the residual solvent.
In the same sample example, 2-methyl-5-fluorophenol can also be synthesized by the following method, which specifically comprises the following steps:
(1) firstly, preparing triethylamine hydrochloride-aluminum trichloride ionic liquid: under the protection of nitrogen, triethylamine hydrochloride (137.65g, 1mol) and n-heptane (200mL) are placed in a clean three-neck flask to be stirred and mixed, anhydrous aluminum trichloride (267g, 2mol) is added in batches at room temperature in the stirring process, stirring is continued for 3 hours after the addition is finished to form ionic liquid, standing and layering are carried out, the upper layer is a protective solvent n-heptane, the lower layer is the ionic liquid, and the ionic liquid is placed in a dryer to be stored;
placing the prepared ionic liquid (15g) into a dry 500mL three-neck flask under the nitrogen atmosphere, adding p-fluorotoluene (220.3g, 2mol) and 1, 2-dichloroethane (300mL), slowly dropwise adding cyclohexanol (25.04g, 0.25mol) under the stirring condition, controlling the reaction temperature at 40 ℃, after dropwise adding, continuing to stir at the temperature for 6 hours, pouring the reaction system into a separating funnel, washing with 50mL of water for 3 times, carrying out reduced pressure distillation on an organic phase, and recovering the solvent and the redundant p-fluorotoluene to obtain a crude product 33.9g, wherein the content of 1-cyclohexyl-2-methyl-5-fluorobenzene is 84%;
(2) adding the 1-cyclohexyl-2-methyl-5-fluorobenzene crude product obtained in the step (1) and cyclohexanone (200mL) into a high-pressure reaction kettle, stirring and dissolving, then adding a sodium carbonate aqueous solution (100g) with the mass fraction of 5%, introducing oxygen (5Mpa) into the kettle, heating to 120 ℃, stirring and reacting for 10 hours, standing and layering after the reaction is finished, and keeping an organic phase;
(3) and (3) transferring the organic phase obtained in the step (2) to a 500mL three-neck flask, adding p-toluenesulfonic acid (0.35g, 0.002mol), stirring and reacting at 25 ℃ for 5 hours, neutralizing the pH value of a system to be 6-7 with saturated sodium bicarbonate after the reaction is finished, standing and layering, carrying out vacuum distillation on the organic phase to obtain 16.6g of yellow liquid product, wherein the purity of 2-methyl-5-fluorophenol is 83%, and recovering the residual solvent.
Example 3
A synthetic method of 2, 4, 6-trimethylphenol, wherein the structural formula of the 2, 4, 6-trimethylphenol is as follows:
the method specifically comprises the following steps:
(1) adding mesitylene (240.4g, 2mol), cyclopentene (136.2g, 2mol) and 1, 2-dichloroethane (600mL) into a high-pressure reaction kettle, uniformly stirring, cooling to-10 ℃, slowly introducing hydrogen fluoride gas (40g, 2mol) into the high-pressure reaction kettle for multiple times, keeping the temperature not more than 5 ℃, and continuously stirring for reacting for 2 hours after the temperature is not more than 5 ℃; adding 200mL of water into the kettle, adjusting the pH value to be neutral by using sodium hydroxide, standing for layering, carrying out reduced pressure distillation on an organic phase, and recovering a solvent to obtain 320.7g of a crude product with the 1-cyclopentyl-2, 4, 6-trimethylbenzene content of 90%;
(2) adding propionitrile (600mL) into the 1-cyclopentyl-2, 4, 6-trimethylbenzene crude product obtained in the step (1), stirring to dissolve, transferring into a 1000mL three-neck flask, adding N-hydroxyphthalimide (2.5g, 0.015mol) and dimethyldioxirane (1.1g, 0.015mol), introducing oxygen at 70 ℃, stirring to react for 5 hours, carrying out reduced pressure distillation to recover propionitrile, cooling to room temperature, adding cyclopentanone (600mL) into the residue, adding 5 wt% of sodium hydroxide solution (60g), stirring for 2 hours, standing and demixing to obtain an organic phase;
(3) transferring the organic phase obtained in the step (2) into a 1000mL three-neck flask, adding perchloric acid (1.5g, 0.015mol), stirring and reacting at 60 ℃ for 2 hours, neutralizing the pH value of a system to be 6-7 by using saturated sodium bicarbonate after the reaction is finished, standing and layering, and recovering the solvent by organic phase vacuum distillation to obtain 203.5g of white solid 2, 4, 6-trimethylphenol with the purity of 95%, wherein the hydrogen spectrum of the 2, 4, 6-trimethylphenol is shown in FIG. 3.
In this embodiment, the synthesis of 2, 4, 6-trimethylphenol can also be accomplished by the following method, which specifically comprises the following steps:
(1) adding mesitylene (240.4g, 2mol), bromocyclopentane (298.1g, 2mol) and 1, 2-dichloroethane (600mL) into a high-pressure reaction kettle, uniformly stirring, cooling to-10 ℃, slowly introducing hydrogen fluoride gas (60g, 3mol) and boron trifluoride gas (68g, 1mol) into the high-pressure reaction kettle for multiple times, keeping the temperature not more than 5 ℃, and continuously stirring for reacting for 2 hours after the temperature is kept to be not more than 5 ℃; adding 200mL of water into the kettle, adjusting the pH value to be neutral by using sodium hydroxide, standing for layering, carrying out reduced pressure distillation on an organic phase, and recovering a solvent to obtain 336.5g of a crude product with the 1-cyclopentyl-2, 4, 6-trimethylbenzene content of 91%;
(2) adding the 1-cyclopentyl-2, 4, 6-trimethylbenzene crude product obtained in the step (1), 4-hydroxy-2, 2, 6, 6-tetramethylpiperidine oxide (2.58g, 0.015mol) and cyclopentanone (400mL) into a high-pressure reaction kettle, stirring and dissolving, then adding a sodium carbonate aqueous solution (200g) with the mass fraction of 5%, introducing oxygen (0.5Mpa) into the kettle, heating to 105 ℃, stirring and reacting for 15 hours, standing and layering after the reaction is finished, and keeping an organic phase;
(3) and (3) transferring the organic phase obtained in the step (2) to a 1000mL three-neck flask, adding perchloric acid (1.5g, 0.015mol), stirring and reacting at 60 ℃ for 2 hours, neutralizing the pH value of a system to be 6-7 by using saturated sodium bicarbonate after the reaction is finished, standing and layering, and carrying out vacuum distillation on the organic phase to recover the solvent to obtain 194.2g of white solid 2, 4, 6-trimethylphenol with the purity of 92%.
In the same sample, 2, 4, 6-trimethylphenol can also be synthesized by the following method, which comprises the following steps:
(1) putting 98 wt% concentrated sulfuric acid (0.5g, 0.005mol) into a 1000mL three-neck flask, adding mesitylene (360.6g, 3mol), stirring and slowly dropwise adding cyclopentanol (86.2g, 1mol), controlling the reaction temperature at 40 ℃, continuing to stir at the temperature for 1 hour after dropwise adding, pouring the reaction system into a separating funnel, washing with 100mL of water for 3 times, carrying out reduced pressure distillation on an organic phase, and recovering redundant mesitylene to obtain 145g of crude product with the 1-cyclopentyl-2, 4, 6-trimethylbenzene content of 86%;
(2) adding the 1-cyclopentyl-2, 4, 6-trimethylbenzene crude product obtained in the step (1) and cyclopentanone (400mL) into a high-pressure reaction kettle, stirring and dissolving, then adding a sodium carbonate aqueous solution (200g) with the mass fraction of 5%, introducing oxygen (5Mpa) into the kettle, heating to 120 ℃, stirring and reacting for 10 hours, standing and layering after the reaction is finished, and keeping an organic phase;
(3) and (3) transferring the organic phase obtained in the step (2) to a 500mL three-neck flask, adding perchloric acid (0.5g, 0.005mol), stirring and reacting at 60 ℃ for 2 hours, neutralizing the pH value of a system to be 6-7 by using saturated sodium bicarbonate after the reaction is finished, standing and layering, and carrying out vacuum distillation on the organic phase to recover the solvent to obtain 179g of white solid 2, 4, 6-trimethylphenol with the purity of 88%.
Example 4
A method for synthesizing 4-dimethylamino phenol, wherein the structural formula of the 4-dimethylamino phenol is as follows:
the method specifically comprises the following steps:
(1) adding an MCM-22 molecular sieve (5g), N-dimethylaniline (242.4g and 2mol) and 1, 2-dichloroethane (300mL) into a dry 1000mL three-neck flask, slowly dropwise adding cyclohexene (82.1g and 1mol) under the stirring condition, controlling the reaction temperature at 10 ℃, and stirring for 8 hours at room temperature after dropwise adding is finished; filtering the reaction liquid, using filter residues for the next reaction, carrying out reduced pressure distillation on the filtrate, recovering the solvent and redundant N, N-dimethylaniline to obtain 170.6g of crude product, wherein the content of 1-cyclohexyl-4-dimethylamino benzene is 82%;
(2) adding acetonitrile (300mL) into the 1-cyclohexyl-4-dimethylamino benzene crude product obtained in the step (1), stirring for dissolving, transferring into a 500mL three-neck flask, adding N-hydroxyphthalimide (0.817g, 0.005mol) and perbenzoic acid (0.69g, 0.005mol), introducing air at room temperature, stirring for reacting for 15 hours, carrying out reduced pressure distillation for recovering acetonitrile, adding cyclohexanone (300mL) into the residue, adding 1 wt% of sodium hydroxide aqueous solution (40g), stirring for 1 hour, standing for layering, and obtaining an organic phase;
(3) and (3) transferring the organic phase obtained in the step (2) to a 500mL three-neck flask, adding 98 wt% concentrated sulfuric acid (1g, 0.01mol), stirring at room temperature for 10 hours to react, neutralizing the pH value of a system to be 6-7 with saturated sodium bicarbonate after the reaction is finished, standing for layering, and carrying out vacuum distillation on the organic phase to recover the solvent to obtain 88g of gray black solid 4-dimethylamino phenol with the purity of 92%, wherein the hydrogen spectrum of the 4-dimethylamino phenol is shown in FIG. 4.
In this embodiment, the synthesis of 4-dimethylaminophenol can be further performed by the following method, which specifically comprises the following steps:
(1) adding an MCM-22 molecular sieve (5g), N-dimethylaniline (242.4g and 2mol) and 1, 2-dichloroethane (300mL) into a dry 500mL three-neck flask, slowly dropwise adding bromocyclohexane (163.1g and 1mol) under the stirring condition, controlling the reaction temperature to be 10 ℃, and stirring for 8 hours at room temperature after dropwise adding is finished; filtering the reaction liquid, using filter residues for the next reaction, carrying out reduced pressure distillation on the filtrate, recovering the solvent and redundant N, N-dimethylaniline to obtain 174.2g of crude product, wherein the content of 1-cyclohexyl-4-dimethylamino benzene is 83%;
(2) adding the 1-cyclohexyl-4-dimethylamino benzene crude product obtained in the step (1), 4-amino-2, 2, 6, 6-tetramethyl piperidine oxide (0.85g, 0.005mol) and cyclohexanone (200mL) into a high-pressure reaction kettle, stirring and dissolving, then adding a sodium carbonate aqueous solution (100g) with the mass fraction of 5%, introducing oxygen (0.5Mpa) into the kettle, heating to 95 ℃, stirring and reacting for 15 hours, standing and layering after the reaction is finished, and keeping an organic phase;
(3) and (3) transferring the organic phase obtained in the step (2) to a 500mL three-neck flask, adding 98 wt% concentrated sulfuric acid (1g, 0.01mol), stirring at room temperature for 10 hours for reaction, neutralizing the pH value of a system to be 6-7 with saturated sodium bicarbonate after the reaction is finished, standing for layering, and carrying out vacuum distillation on the organic phase to recover the solvent, so as to obtain 90g of gray black solid 4-dimethylamino phenol with the purity of 85%.
In the same example, 4-dimethylaminophenol can also be synthesized by the following method, which specifically comprises the following steps:
(1) adding an MCM-22 molecular sieve (5g), N-dimethylaniline (242.36g, 2mol) and 1, 2-dichloroethane (300mL) into a dry 500mL three-neck flask, slowly dropwise adding cyclohexanol (100.2g, 1mol) under the stirring condition, controlling the reaction temperature at 10 ℃, and stirring for 8 hours at room temperature after dropwise adding is finished; filtering the reaction liquid, using filter residues for the next reaction, carrying out reduced pressure distillation on the filtrate, recovering the solvent and redundant N, N-dimethylaniline to obtain a crude product 171.2g, wherein the content of 1-cyclohexyl-4-dimethylamino benzene is 84%;
(2) adding the 1-cyclohexyl-4-dimethylamino benzene crude product obtained in the step (1) and cyclohexanone (200mL) into a high-pressure reaction kettle, stirring and dissolving, then adding a sodium carbonate aqueous solution (100g) with the mass fraction of 5%, introducing oxygen (5Mpa) into the kettle, heating to 110 ℃, stirring and reacting for 10 hours, standing and layering after the reaction is finished, and keeping an organic phase;
(3) and (3) transferring the organic phase obtained in the step (2) to a 500mL three-neck flask, adding 98 wt% concentrated sulfuric acid (1g, 0.01mol), stirring at room temperature for reaction for 10 hours, neutralizing the pH value of a system to be 6-7 with saturated sodium bicarbonate after the reaction is finished, standing for layering, and carrying out vacuum distillation on the organic phase to recover the solvent, so as to obtain 85g of gray black solid 4-dimethylaminophenol with the purity of 81%.
The above description is only for the preferred embodiment of the present invention, but the scope of the present invention is not limited thereto, and any person skilled in the art should be considered as the technical scope of the present invention, and equivalents and modifications thereof should be included in the technical scope of the present invention.
Claims (9)
1. A method for synthesizing substituted phenol is characterized by comprising the following steps:
(1) carrying out Friedel-crafts alkylation reaction on substituted benzene shown in a formula I to obtain cyclopentyl benzene containing a substituent group or cyclohexyl benzene containing a substituent group shown in a formula II;
(2) performing oxidation reaction on the substituted cyclopentyl benzene or the substituted cyclohexyl benzene shown in the formula II to obtain substituted phenyl cyclopentyl hydroperoxide or substituted phenyl cyclohexyl hydroperoxide shown in the formula III;
(3) carrying out cracking reaction on phenyl cyclopentyl hydroperoxide containing substituent groups or phenyl cyclohexyl hydroperoxide containing substituent groups shown in a formula III to obtain substituted phenol;
in the formulas I, II and III, R is one or more substituent groups at any possible position on a benzene ring.
2. The method for synthesizing substituted phenol according to claim 1, wherein in the step (1), substituted benzene represented by formula I and alkylating agent are subjected to Friedel-crafts alkylation reaction under the condition of first catalyst to obtain substituted cyclopentyl benzene or substituted cyclohexyl benzene represented by formula II.
3. The method of claim 1, wherein the alkylating agent is cyclopentene, cyclohexene, or a halogenated cyclopentane, a halogenated cyclohexane, or a cyclopentanol, or a cyclohexanol; preferably, the halogenated cyclopentane is chloro-cyclopentane or bromo-cyclopentane, and the halogenated cyclohexane is chloro-cyclohexane or bromo-cyclohexane.
4. The method for synthesizing substituted phenol according to claim 2 or 3, wherein the first catalyst is a composite ionic liquid or molecular sieve catalyst prepared from Lewis acid, protonic acid, Lewis acid and triethylamine hydrochloride ionic liquid; preferably, the first catalyst is aluminum trichloride AlCl3FeCl, ferric chloride3Titanium tetrachloride TiCl4ZnCl, zinc chloride2SnCl, tin chloride2Boron trifluoride BF3Sulfuric acid H2SO4Phosphoric acid H3PO4HF, triethylamine hydrochloride-aluminium trichloride Et3NHCl-AlCl3The composite ionic liquid and the MCM-22 molecular sieve.
5. The method for synthesizing substituted phenol according to any one of claims 1 to 4, wherein the substituted benzene represented by formula I is mono-substituted benzene or poly-substituted benzene, R is alkyl, alkoxy, alkoxyalkyl, alkylamino, dialkylamino, acylamino, acyloxy, halogen, phenyl, substituted phenyl, fused ring aryl, substituted fused ring aryl, heterocyclic aryl or substituted heterocyclic aryl; preferably, the substituent of the substituted phenyl, the substituted condensed ring aromatic group and the substituted heterocyclic aromatic group is nitro, trihalomethyl, acyl, formyl, cyano, sulfonic acid group or carboxyl.
6. The method for synthesizing a substituted phenol according to any one of claims 1 to 5, wherein in the step (2), the substituted cyclopentylbenzene represented by the formula II or the substituted cyclohexylbenzene is subjected to an oxidation reaction with an oxidizing agent under the condition of a second catalyst to obtain a substituted phenylcyclopentyl hydroperoxide or a substituted phenylcyclohexyl hydroperoxide represented by the formula III.
7. The method of synthesizing a substituted phenol according to claim 6 wherein said oxidizing agent is air or oxygen;
the second catalyst is one or the combination of more of 2, 2, 6, 6-tetramethyl piperidine nitroxide free radical and derivatives thereof, N-hydroxyl substituted cyclic imide compounds and sodium carbonate;
wherein, the 2, 2, 6, 6-tetramethyl piperidine nitroxide free radical and the derivatives thereof are selected from one or more compounds with the following structures:
the N-hydroxy substituted cyclic imide compound is selected from one or more of N-hydroxyphthalimide, 4-amino-N-hydroxyphthalimide, 3-amino-N-hydroxyphthalimide, N-hydroxyphenetetrachlorophthalimide, N-hydroxytetrabromophthalimide, N-hydroxytoluenetriomide, N-hydroxyphenyl-1, 2, 4-trimethylimide, pyridine-2, 3-dicarboximide, N-hydroxysuccinimide or N-hydroxy (tartrimide).
8. The method for synthesizing a substituted phenol according to any one of claims 1 to 7, wherein in the step (3), the substituted phenylcyclopentyl hydroperoxide or the substituted phenylcyclohexyl hydroperoxide having a substituent represented by the formula III is subjected to a cleavage reaction in the presence of an acid catalyst to obtain a substituted phenol.
9. The method of claim 8, wherein the acid catalyst is one or more of perchloric acid, sulfuric acid, phosphoric acid, or p-toluenesulfonic acid.
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