Method for producing tetrakisphenol compound having biphenyl skeleton

Abstract

The present invention addresses the problem of providing a novel production method that has a high reaction selectivity for a tetrakisphenol compound in a reaction between a phenol and a 4,4'-diacylbiphenyl. As a means for solving this problem, the present invention provides a method of producing a tetrakisphenol compound represented by formula (3), said method being characterized by comprising reacting a phenol represented by formula (1) with a 4,4'-diacylbiphenyl represented by formula (2) in the presence of a specific alkanesulfonic acid.

Description

[Technical Field]

[0001] The present invention relates to a novel method for producing a tetrakisphenol compound by reacting a phenol with a 4,4'-diacylbiphenyl. [Background technology]

[0002] Tetrakisphenol compounds are usefully used as raw materials for epoxy resins used in sealing materials, laminate materials, and electrical insulating materials for integrated circuits, curing agents for epoxy resins, color developers and anti-fading agents used in thermal recording, raw materials for electronic materials and photosensitive materials, and the like. They are also widely and usefully used as additives for antioxidants, disinfectants, antibacterial and antifungal agents, and the like, and as inclusion compounds. As a method for producing a tetrakisphenol compound having a biphenyl skeleton according to the present invention, for example, Patent Document 1 specifically describes a method in which a phenol and a 4,4'-diacylbiphenyl are reacted by dehydration condensation in the presence of hydrogen chloride gas using 3-mercaptopropionic acid as a co-catalyst. Patent Document 1 also describes that preferred acid catalysts include hydrochloric acid, sulfuric acid, p-toluenesulfonic acid, oxalic acid, boron trifluoride, anhydrous aluminum chloride, and zinc chloride, with p-toluenesulfonic acid, sulfuric acid, and hydrochloric acid being particularly preferred.

[0003] Acidic catalysts such as hydrogen chloride gas used in conventional manufacturing methods have the following problems: The use of hydrogen chloride gas requires the introduction of dedicated equipment and is difficult to handle. (Concentrated) hydrochloric acid is relatively easier to handle than hydrogen chloride gas, but it reduces the volume ratio and requires equipment to recover the hydrochloric acid, making it unsuitable for industrial use. In addition, sulfuric acid has a strong dehydrating effect, so it generates many by-products and reduces the selectivity for the target compound. Furthermore, as a result of confirmation by the present inventors, it has become clear that, as shown in the comparative example described below, the reaction selectivity is low when hydrogen chloride gas or p-toluenesulfonic acid is used as an acidic catalyst in the reaction of phenols with 4,4'-diacylbiphenyls. [Prior art documents] [Patent documents]

[0004] [Patent Document 1] Japanese Patent Application Publication No. 08-027052 Summary of the Invention [Problem to be solved by the invention]

[0005] The present invention has been made in light of the above-mentioned circumstances, and an object of the present invention is to provide a novel method for producing a tetrakisphenol compound in a reaction between a phenol and a 4,4'-diacylbiphenyl, which method has excellent reaction selectivity for the production of a tetrakisphenol compound. [Means for solving the problem]

[0006] The present inventors have investigated the reaction of phenols with 4,4'-diacylbiphenyls and found that the reaction selectivity of tetrakisphenol compounds is extremely high when the reaction is carried out in the presence of a specific alkanesulfonic acid, thereby completing the present invention.

[0007] The present invention is as follows. 1. A phenol represented by the following formula (1), [ka] (In the formula, each R independently represents a linear or branched alkyl group having 1 to 6 carbon atoms, a cyclic alkyl group having 5 to 6 carbon atoms, or an aryl group having 6 to 12 carbon atoms, and each n independently represents 0 or an integer of 1 to 4.) A 4,4'-diacylbiphenyl represented by the following formula (2): [ka] (In the formula, R1 and R2 each independently represent a linear or branched alkyl group having 1 to 6 carbon atoms, and m each independently represents 0, 1, or 2.) A method for producing a tetrakisphenol compound represented by the following formula (3), characterized by carrying out a reaction in the presence of an alkanesulfonic acid having 1 to 4 carbon atoms: [ka] (In the formula, R, R1, R2, m, and n are defined as in formulas (1) and (2).) 2. The production method according to 1., further characterized in that the reaction is carried out in the presence of a thiol compound. 3. The production method according to 1. or 2., characterized in that the reaction is carried out while adding a solution containing the 4,4'-diacylbiphenyl represented by the formula (2) to a solution containing the phenol represented by the formula (1). [Effects of the Invention]

[0008] The reaction of phenols with 4,4'-diacylbiphenyls according to the present invention has an extremely high reaction selectivity for the target product, tetrakisphenol compounds, compared to conventional methods using hydrogen chloride gas or acidic catalysts such as p-toluenesulfonic acid, and therefore can efficiently produce tetrakisphenol compounds, making it an extremely useful industrial production method. [Brief explanation of the drawings]

[0009] [Figure 1] 1 is a graph showing the change in the residual rate (%) of 4,4′-diacetylbiphenyl in Example 1 and Comparative Examples 1 and 2. [Figure 2] 1 is a graph showing the change in reaction selectivity (%) of the target compound represented by the following formula (4) in Example 1 and Comparative Examples 1 and 2. [Figure 3] 1 is a graph showing the change in the residual rate (%) of 4,4′-diacetylbiphenyl in Example 2 and Comparative Examples 3 to 5. [Figure 4] 4 is a graph showing the change in the residual rate (%) of 4,4′-diacetylbiphenyl in Example 2 and Comparative Examples 3 and 5, which is an enlarged graph of a part of FIG. [Figure 5]1 is a graph showing the change in reaction selectivity (%) of the target compound represented by the following formula (4) in Example 2 and Comparative Examples 3 to 5. DETAILED DESCRIPTION OF THE INVENTION

[0010] The present invention will be described in detail below. As shown in the following reaction scheme, the production method of the present invention is a production method in which 1 equivalent of a tetrakisphenol compound represented by formula (3) and 2 equivalents of water are produced by a dehydration condensation reaction between 4 equivalents of a phenol represented by formula (1) and 1 equivalent of a 4,4'-diacylbiphenyl represented by formula (2). [ka] (In the formula, R, R1, R2, m, and n are defined as in formulas (1) and (2).)

[0011] In the above formulas (1) and (3), R each independently represents a linear or branched alkyl group having 1 to 6 carbon atoms, a cyclic alkyl group having 5 to 6 carbon atoms, or an aryl group having 6 to 12 carbon atoms. When R is a linear or branched alkyl group having 1 to 6 carbon atoms, it is preferably a linear or branched alkyl group having 1 to 4 carbon atoms, and more preferably an alkyl group having 1 carbon atom, i.e., a methyl group. When R is a cyclic alkyl group having 5 to 6 carbon atoms, it is more preferably a cyclic alkyl group having 6 carbon atoms, i.e., a cyclohexyl group. When R is an aryl group having 6 to 12 carbon atoms, it is preferably an aryl group having 6 or 8 carbon atoms, and more preferably an aryl group having 6 carbon atoms, i.e., a phenyl group. The position at which R is bonded to the benzene ring is preferably the ortho position relative to the hydroxy group. In the above formulas (1) and (3), n is preferably 0 or an integer of 1 to 3, more preferably 0, 1 or 2, and particularly preferably 0 or 1. In the above formulas (2) and (3), R1 and R2 each independently represent a linear or branched alkyl group having 1 to 6 carbon atoms. R1 and R2 are preferably linear or branched alkyl groups having 1 to 4 carbon atoms, more preferably alkyl groups having 1 or 2 carbon atoms, and particularly preferably alkyl groups having 1 carbon atom, i.e., a methyl group. In the above formulas (2) and (3), m is preferably 0 or 1, with 0 being particularly preferred.

[0012] Suitable examples of the tetrakisphenol compound represented by the above formula (3) obtainable by the production method of the present invention include the following compounds (4) and (5). [ka]

[0013] <Alkanesulfonic acid> The production method of the present invention uses an alkane sulfonic acid having 1 to 4 carbon atoms as the acidic catalyst. Specific examples of the alkane sulfonic acid having 1 to 4 carbon atoms include methanesulfonic acid, ethanesulfonic acid, n-propanesulfonic acid, isopropanesulfonic acid, n-butanesulfonic acid, isobutanesulfonic acid, sec-butanesulfonic acid, and tert-butanesulfonic acid. Among these, an alkane sulfonic acid having 1 or 2 carbon atoms, i.e., methanesulfonic acid and ethanesulfonic acid, is preferred, with methanesulfonic acid being particularly preferred. The amount of the alkane sulfonic acid used is preferably in the range of 0.1 to 5.0 mol, more preferably 0.5 to 2.0 mol, per mol of the 4,4'-diacylbiphenyl represented by the above formula (2).

[0014] <Thiol compounds> In the production method of the present invention, a thiol compound may be used as a co-catalyst in combination with an acidic catalyst composed of a specific alkane sulfonic acid. The thiol compound of the present invention is a compound having a mercapto group, and is not particularly limited as long as it does not adversely affect the reaction selectivity, etc. Examples of such compounds include carboxylic acids having a mercapto group, such as 3-mercaptopropionic acid and thioglycolic acid; alkyl mercaptans having 1 to 12 carbon atoms, such as methyl mercaptan, 1-octanethiol (octyl mercaptan), and 1-dodecanethiol (lauryl mercaptan); and mercaptoalcohols, such as mercaptoethanol and mercaptobutanol. Among these, alkyl mercaptans having 1 to 12 carbon atoms, such as 1-octanethiol, are preferred. Furthermore, when a thiol compound is used, the thiol compound may be converted into a sodium salt and used in the form of an aqueous solution. When such a thiol compound is used, the amount used is preferably in the range of 1 to 10% by weight relative to the 4,4'-diacylbiphenyls represented by the above formula (2). If the amount is less than 1% by weight, the co-catalyst function cannot be fully exerted, and if the amount exceeds 10% by weight, the co-catalyst function cannot be exerted any more, and the selectivity remains almost the same.

[0015] <Reaction conditions> The reaction conditions in the production method of the present invention will be explained below. The amount of phenols represented by formula (1) used is preferably 4 to 20 moles, more preferably 5 to 15 moles, and particularly preferably 8 to 12 moles, per mole of 4,4'-diacylbiphenyls represented by formula (2). If the amount of phenols represented by formula (1) used is less than 4 moles, the reaction is slow and, in addition to the desired tetrakisphenol compound represented by formula (3), a large amount of by-products, such as trinuclear compounds in which the phenols are further substituted, is produced, which is undesirable. Furthermore, if more than 20 moles are used, the reaction rate increases, but the amount of unreacted phenols recovered increases, reducing productivity and making this impractical. The reaction temperature is preferably in the range of 0 to 80°C, more preferably in the range of 30 to 60°C. The reaction is usually carried out under normal pressure, but depending on the boiling point of the organic solvent that may be used, the reaction may be carried out under increased or reduced pressure so that the reaction temperature falls within the above range. The reaction time varies depending on the amount of catalyst and the reaction temperature, but is usually in the range of 1 to 20 hours, and it is preferable that the reaction is completed within the range of 1 to 10 hours. In the reaction, the method of adding raw materials is not particularly limited, but a method of mixing a mixture of 4,4'-diacetylbiphenyls represented by formula (2) and the remaining amount of phenols represented by formula (1) with a solution containing a portion of the phenols represented by formula (1), an alkane sulfonic acid as an acid catalyst, and optionally a co-catalyst, is preferred from the viewpoint of reaction selectivity. In the case of the mixing method, the mixing time is set within a range of 0.5 to 5 hours. The reaction is carried out so that the amount of raw materials used in the mixed solution is the same as that described above.

[0016] In carrying out the production method of the present invention, the use of a reaction solvent is not necessary if it does not cause problems with operability. However, it may be used for reasons such as improving operability and reaction rate during industrial production. The reaction solvent used is not particularly limited as long as it does not distill from the reaction vessel at the reaction temperature and is inert to the reaction. Examples include aromatic hydrocarbons such as toluene, xylene, and benzene; halogenated aromatic hydrocarbons such as chlorobenzene and dichlorobenzene; aliphatic hydrocarbons such as pentane, n-hexane, cyclohexane, and heptane; aliphatic alcohols such as methanol, n-butanol, t-butanol, and cyclohexanol; and aliphatic or cyclic ethers such as diethyl ether, diisopropyl ether, methyl t-butyl ether, diphenyl ether, tetrahydrofuran, and dioxane. Among reaction solvents, aromatic hydrocarbons and halogenated aromatic hydrocarbons are preferred, with aromatic hydrocarbons being more preferred. The amount used is not particularly limited, but from an economical standpoint, it is usually in the range of 0.1 to 10 times by weight, preferably 0.1 to 2 times by weight, and more preferably 0.1 to 1 times by weight relative to the phenol represented by formula (1) above.

[0017] In the production method of the present invention, water is produced by a dehydration condensation reaction between a phenol represented by the above formula (1) and a 4,4'-diacylbiphenyl represented by the above formula (2). Carrying out the reaction under dehydration conditions that remove water from the reaction system, such as the water produced by the reaction and water containing the catalyst, is preferred because the reaction proceeds more quickly than without dehydration, the production of by-products is suppressed, and the target product can be obtained in a higher yield. The dehydration method is not particularly limited, but examples include dehydration by adding a dehydrating agent, dehydration under reduced pressure, and dehydration by azeotropy with a solvent under normal or reduced pressure. The dehydrating agent that can be added as needed is not particularly limited, and examples thereof include organic dehydrating agents having an orthoester skeleton such as methyl orthoformate, ethyl orthoformate, methyl orthoacetate, ethyl orthopropionate, methyl ortho-n-butyrate, methyl ortho-i-butyrate, and 1,1,1-trimethoxyoctane; zeolites such as molecular sieve (3A) and molecular sieve (4A); and inorganic anhydrous salts that can contain water of crystallization within the molecule, such as calcium chloride (anhydrous), calcium sulfate (anhydrous), magnesium chloride (anhydrous), magnesium sulfate (anhydrous), potassium carbonate (anhydrous), potassium sulfide (anhydrous), potassium sulfite (anhydrous), sodium sulfate (anhydrous), sodium sulfite (anhydrous), and copper sulfate (anhydrous).

[0018] <Post-processing> The post-treatment method in the production method of the present invention will be described below. The end point of the reaction can be confirmed by liquid chromatography or gas chromatography analysis. The end point of the reaction is preferably determined as the point at which the unreacted 4,4'-diacylbiphenyls represented by the above formula (2) disappear or the increase in the target tetrakisphenol compound represented by the above formula (3) is no longer observed. To purify the target product from the resulting reaction mixture, a known method can be used. For example, alkaline water such as an aqueous solution of sodium hydroxide is added to the reaction mixture to neutralize it. After neutralization, the aqueous layer containing the neutralized salt is separated and removed. If necessary, a solvent that can be separated from water, such as toluene or xylene, may be added. Thereafter, the target tetrakisphenol compound represented by formula (3) can be obtained as a crystalline or non-crystalline (amorphous) substance by crystallization or precipitation and filtration. Before the crystallization or precipitation operation, the obtained oil layer may be washed with water, or the solvent or the phenol represented by formula (1) may be distilled off, and an appropriate crystallization solvent may be added, if necessary. If the target product is not obtained as a crystal or solid (amorphous), the target product can be obtained by removing the raw material, the phenol represented by the above formula (1), from the resulting reaction mixture by distillation or the like, or a highly pure product can be obtained by column separation or the like.

[0019] The tetrakisphenol compound represented by the above formula (3) obtained by the production method of the present invention is highly pure and is therefore useful as a raw material or curing agent for photosensitive resist materials, photosensitive polyimide materials, photosensitive transparent resin insulating film materials, phenolic resins, and epoxy resins. It is also expected to be used as an additive for antioxidants, disinfectants, antibacterial and antifungal agents, etc., and as an inclusion compound. [Example]

[0020] EXAMPLES The present invention will be specifically explained below with reference to examples and comparative examples, but the present invention is not limited to these examples and comparative examples. In the examples and comparative examples, the residual rate of the 4,4'-diacylbiphenyls represented by the above formula (2), and the purity and selectivity of the tetrakisphenol compound represented by the above formula (3) were measured by the following methods. [Analysis method] Apparatus: Shimadzu Corporation Prominence UFLC (liquid chromatography) Pump: LC-20AD Column oven: CTO-20A Detector: SPD-20A Column: HALO C18 (inner diameter 3 mm, length 75 mm) Oven temperature: 50℃ Flow rate: 0.7mL / min Mobile phase: (A) 0.2% acetic acid aqueous solution, (B) methanol Gradient conditions: (B) Volume % (time from the start of analysis) 50%(0min)→100%(7.5min)→100%(15min) Sample injection volume: 5 μL Detection wavelength: 280 nm

[0021] The area percentage of each component relative to the total area of all components detected by the above analytical method was calculated. Using the calculated values, the values calculated by the following formulas (I) and (II) were defined as the residual rate of 4,4'-diacylbiphenyls represented by the above formula (2) (hereinafter sometimes referred to as "residual rate") and the reaction selectivity of tetrakisphenol compounds represented by the above formula (3) (hereinafter sometimes referred to as "reaction selectivity"), respectively. (A) to (D) in formula (I) and formula (II) have the following meanings. (A): Area percentage of 4,4'-diacylbiphenyls represented by the above formula (2) (B): Area percentage of phenols represented by the above formula (1) (C): Area percentage of the solvent used in the reaction, such as toluene (D): Area percentage of the tetrakisphenol compound represented by the above formula (3) <Formula (I)> "Survival rate %" = (A) ÷ (100-(B)-(C)) x 100 <Formula (II)> "Reaction selectivity %" = (D) ÷ (100 - (B) - (C)) × 100

[0022] <Synthesis of compound (4)> [ka] Example 1 Phenol (4.0 g, 42.5 mmol) and methanesulfonic acid (1.5 g, 15.6 mmol) were added to a 100 mL test tube and stirred at 50°C. 4,4'-Diacetylbiphenyl (1.0 g, 4.20 mmol) was added and stirred for 26 hours. After stirring, the reaction selectivity of the target compound represented by formula (4) above was 75%.

[0023] <Comparative Example 1> Phenol (4.0 g, 42.5 mmol) and p-toluenesulfonic acid (2.9 g, 16.8 mmol) were added to a 100 mL test tube and stirred at 50°C. 4,4'-Diacetylbiphenyl (1.0 g, 4.20 mmol) was added and stirred for 26 hours. After stirring, the reaction selectivity of the target compound represented by formula (4) above was 36%.

[0024] <Comparative Example 2> Phenol (12.0 g, 127.1 mmol) and methanol (5.0 g) were added to a 100 mL four-neck flask, and the system was purged with hydrochloric acid gas. After heating to 50°C, 4,4'-diacetylbiphenyl (3.0 g, 12.6 mmol) was added and stirred for 26 hours. After stirring, the reaction selectivity of the target compound represented by the above formula (4) was 39%.

[0025] The changes in the residual rate (%) of 4,4'-diacetylbiphenyl and the reaction selectivity (%) of the target compound represented by the above formula (4) from the start of the reaction until 24 hours later in Example 1 and Comparative Examples 1 and 2 are shown in Figures 1 and 2, respectively. As shown in Figure 1, in Example 1, a specific example of the present invention in which the reaction is carried out in the presence of methanesulfonic acid, 4,4'-diacetylbiphenyl, one of the raw materials, is rapidly consumed. Specifically, the residual rate is about 30% after 1 hour from the start of the reaction, about 7% after 4 hours, and about 1% after 10 hours. This confirms that the reaction proceeds much faster than in Comparative Examples 1 and 2, in which the reaction is carried out in the presence of p-toluenesulfonic acid or hydrochloric acid gas. 2, Example 1, a specific example of the present invention in which the reaction is carried out in the presence of methanesulfonic acid, has a high reaction selectivity for the target compound represented by formula (4). Specifically, the reaction selectivity exceeds 40% four hours after the start of the reaction, whereas Comparative Examples 1 and 2, in which the reaction is carried out in the presence of p-toluenesulfonic acid or hydrochloric acid gas, do not exceed 40% even 26 hours after the start of the reaction. This confirms that the production method of the present invention has an extremely high reaction selectivity for the target compound represented by formula (4).

[0026] Next, Examples 2 to 4 and Comparative Examples 3 to 5 were carried out in which a co-catalyst (mercaptoacetic acid) was used in combination. <Example 2> Phenol (4.0 g, 42.5 mmol), methanesulfonic acid (1.5 g, 15.6 mmol), and mercaptoacetic acid (0.15 g, 1.63 mmol) were added to a 100 mL test tube and stirred at 50°C. 4,4'-Diacetylbiphenyl (1.0 g, 4.20 mmol) was added and stirred for 24 hours. After stirring, the reaction selectivity of the target compound represented by formula (4) above was 72%.

[0027] Example 3 Phenol (7.9 g, 83.9 mmol), methanesulfonic acid (1.5 g, 15.6 mmol), and mercaptoacetic acid (0.16 g, 1.74 mmol) were added to a 100 mL test tube and stirred at 50°C. 4,4'-Diacetylbiphenyl (2.0 g, 8.93 mmol) was added and stirred for 24 hours. After stirring, the reaction selectivity of the target compound represented by formula (4) above was 77%.

[0028] Example 4 Phenol (11.9 g, 126.4 mmol), methanesulfonic acid (4.4 g, 45.8 mmol), and mercaptoacetic acid (0.47 g, 5.10 mmol) were added to a 100 mL test tube and stirred at 50°C. 4,4'-Diacetylbiphenyl (3.0 g, 12.6 mmol) was added intermittently in 10 portions over 3.5 hours, and the mixture was stirred for 24 hours. After stirring, the reaction selectivity of the target compound represented by formula (4) above was 85%.

[0029] <Comparative Example 3> Phenol (4.0 g, 42.5 mmol), p-toluenesulfonic acid (2.9 g, 16.8 mmol), and mercaptoacetic acid (0.16 g, 1.74 mmol) were added to a 100 mL test tube and stirred at 50°C. 4,4'-Diacetylbiphenyl (1.0 g, 4.20 mmol) was added and stirred for 24 hours. After stirring, the reaction selectivity of the target compound represented by formula (4) above was 65%.

[0030] <Comparative Example 4> Phenol (4.1 g, 43.6 mmol), 37% aqueous hydrochloric acid (1.5 g), and mercaptoacetic acid (0.16 g, 1.74 mmol) were added to a 100 mL test tube and stirred at 50°C. 4,4'-Diacetylbiphenyl (1.0 g, 4.20 mmol) was added and stirred for 24 hours. After stirring, the reaction selectivity of the target compound represented by formula (4) above was 7%.

[0031] <Comparative Example 5> Phenol (12.0 g, 127.1 mmol), methanol (5.0 g), and mercaptoacetic acid (0.5 g, 5.43 mmol) were added to a 100 mL four-neck flask, and the system was purged with hydrochloric acid gas. After heating to 50°C, 4,4'-diacetylbiphenyl (3.0 g, 12.6 mmol) was added and stirred for 24 hours. After stirring, the reaction selectivity of the target compound represented by the above formula (4) was 34%.

[0032] The changes in the residual rate (%) of 4,4'-diacetylbiphenyl and the reaction selectivity (%) of the target compound represented by the above formula (4) from the start of the reaction until 24 hours later in Example 2 and Comparative Examples 3 to 5, in which methanesulfonic acid and a co-catalyst were used in combination, are shown in Figures 3 to 5, respectively. As shown in Figures 3 to 5, when the methanesulfonic acid according to the present invention was used as an acidic catalyst, the residual rate (%) of 4,4'-diacetylbiphenyl became 0% immediately after the start of the reaction, and the reaction selectivity (%) of the target compound represented by the above formula (4) exceeded 50% within 1 hour from the start of the reaction, and was confirmed to be high, exceeding 70% within a short time of 4 hours from the start of the reaction. On the other hand, when the acidic catalyst was p-toluenesulfonic acid (Comparative Example 3), 4,4'-diacetylbiphenyl was consumed quickly, but the reaction selectivity (%) for the target compound represented by the above formula (4) increased slowly, and the reaction selectivity (%) 24 hours after the start of the reaction was 65%. Furthermore, when a 37% aqueous hydrochloric acid solution (Comparative Example 4) or hydrogen chloride gas (Comparative Example 5) was used, the consumption of 4,4'-diacetylbiphenyl was slow, and the reaction selectivity (%) for the target compound represented by the above formula (4) was confirmed to be extremely low at 7% and 34%, respectively.

[0033] From the results of Example 3, it was confirmed that even when the amount of methanesulfonic acid used relative to 4,4'-diacylbiphenyl was reduced to about 50% of that used in Example 2, the reaction selectivity (%) of the target compound represented by the above formula (4) was high, exceeding 70%, as in Example 2. Furthermore, the results of Example 4 revealed that the reaction selectivity (%) of the target compound represented by the above formula (4) was improved by dividing 4,4'-diacylbiphenyl and adding it intermittently to the reaction system.

Claims

1. A phenol represented by the following formula (1), 【Chemical 1】 (In the formula, each R independently represents a linear or branched alkyl group having 1 to 6 carbon atoms, a cyclic alkyl group having 5 to 6 carbon atoms, or an aryl group having 6 to 12 carbon atoms, and each n independently represents 0 or an integer of 1 to 4.) A 4,4'-diacylbiphenyl represented by the following formula (2): 【Chemistry 2】 (In the formula, R １ and R ２ each independently represents a linear or branched alkyl group having 1 to 6 carbon atoms, and each m independently represents 0, 1, or 2. reacting in the presence of an alkanesulfonic acid having 1 to 4 carbon atoms; A method for producing a tetrakisphenol compound represented by the following formula (3), characterized in that the amount of the alkanesulfonic acid used is in the range of 0.5 to 5.0 moles per mole of the 4,4'-diacylbiphenyl represented by the formula (2): 【Chemistry 3】 (In the formula, R, R １ , R ２ , m, and n are defined as in formulas (1) and (2).

2. The method according to claim 1, further comprising carrying out the reaction in the presence of a thiol compound.

3. 3. The method according to claim 1, wherein the reaction is carried out while adding a solution containing the 4,4'-diacylbiphenyls represented by the formula (2) to a solution containing the phenols represented by the formula (1).

Images