JP2002212123A - Method for producing cyclohexenylphenol - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a method capable of producing a high-purity alkenylphenol in high yield without using a complex and expensive production system by thermally decomposing a cyclohexylidene bisphenol under a mild condition. SOLUTION: This method comprises thermally decomposing a cyclohexylidene bisphenol of general formula I, specifically, e.g. 1,1-bis(4-hydroxyphenyl)-4- heptylcyclohexane in a reaction vessel in the presence of a basic catalyst in an inert gas atmosphere under reduced pressure, distilling the produced phenols with, simultaneously, leaving the produced cyclohexenylphenol in the reaction vessel as the reaction residue liquor and fractionating the cyclohexenylphenol from the reaction residue liquor to obtain the objective cyclohexenylphenol of general formula II, specifically, e.g. 4-(4-n-hepthyl-1-cyclohexenyl)phenol.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to a method for producing cyclohexenylphenols, and more particularly, to cyclohexenylphenol useful as a raw material for producing asymmetric cyclohexylidenebisphenols or as a raw material for producing chemicals for electronic materials. To cyclohexylidenebisphenols by thermal decomposition.

[0002]

2. Description of the Related Art It has been already known that pyrolysis of dihydroxydiarylalkanes in the presence of a basic catalyst causes asymmetric cleavage of the molecule to produce corresponding alkenylphenols and phenols. Utilizing such a reaction, various alkenylphenols have been conventionally produced.

[0003] For example, German Patent Publication No. 1235894.
No.2, dihydroxydiphenylalkanes are thermally decomposed under reduced pressure using alkali metal hydroxide as a catalyst, the reaction product is distilled off, and this is recrystallized to produce purified alkenylphenols. It is stated that it can be obtained.
JP-A-50-37736 discloses that dihydroxydiphenylpropane is heated in the presence of a basic catalyst to distill a reaction product, and this distillate is collected in a polar solvent to obtain p- Methods for obtaining isopropenylphenol are described. Further, Japanese Patent Application Laid-Open No. 2000-159711
In the publication, cyclohexylidenebisphenols are thermally decomposed under reduced pressure in the presence of a basic catalyst, and the product is distilled off. It is described to obtain a purified product of hexenylphenols.

However, according to such a conventional method, the raw material is thermally decomposed and the phenols and alkenylphenols to be purified are once distilled off from the reaction tank under reduced pressure, and this is recrystallized or distilled. Purification by means of (1) above gives a purified product, so two devices, a reaction tank and a purification tank, are required. Furthermore, according to the conventional method, since the reaction purified product is distilled under reduced pressure, particularly when the alkyl group of the target alkyl-substituted cycloalkenylphenol has a large number of carbon atoms, for example, 4- (4-propyl) In the case of -1-cyclohexenyl) phenol, the distillation takes place at a temperature of 22.
0 ° C, high pressure of 8mmHg or more, decompression conditions are required,
Thus, a device that can withstand high temperature and high vacuum is required, which causes an increase in manufacturing cost.

[0005]

SUMMARY OF THE INVENTION The present invention has been made to solve the above-mentioned problems in the conventional production of alkenylphenols, and the phenols to be purified are distilled off from the reaction tank. However, compared to the conventional method, the cyclohexenylidene bisphenol is thermally decomposed under milder conditions so that the formed cyclohexenyl phenol remains in the reaction vessel, and then the cyclohexenyl phenol remains in the reaction vessel. To provide a production method capable of obtaining high-purity alkenylphenols in a high yield without separating a cyclohexenylphenol of interest from a reaction residue obtained by using a complicated and expensive production apparatus. With the goal.

[0006]

According to the present invention, the compound represented by the general formula (I)

[0007]

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(Wherein R ₁ and R ₂ each independently represent a hydrogen atom, an alkyl group having 1 to 4 carbon atoms, a cyclohexyl group or a phenyl group, R ₃ represents an alkyl group having 1 to 12 carbon atoms, n is an integer of 0 to 3, and when n is 2 or 3, R ₃ may be the same as or different from each other, and the cyclohexylidenebisphenol represented by Thermal decomposition in an active gas atmosphere to distill off the generated phenols, while leaving the generated cyclohexenyl phenols in the reaction tank as a reaction residue, and separating cyclohexenyl phenols from the reaction residue General formula (II) characterized by

[0009]

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(Wherein R ₁ , R ₂ and R ₃ are the same as above). A process for producing cyclohexenylphenols represented by the formula:

Further, according to the present invention, a compound represented by the general formula (III):

[0012]

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(Wherein, R ₁ and R ₂ each independently represent a hydrogen atom, an alkyl group having 1 to 4 carbon atoms, a cyclohexyl group or a phenyl group) and a phenol represented by the general formula (IV)

[0014]

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(Wherein, R ₃ represents an alkyl group having 1 to 12 carbon atoms, n is an integer of 0 to 3, and when n is 2 or 3, R ₃ may be the same or different. Is dehydrated and condensed in the presence of an acid catalyst, and the resulting reaction mixture is neutralized with an alkali. The aqueous layer is removed by liquid separation to obtain a compound represented by the general formula ( I)

[0016]

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(Wherein R ₁ and R ₂ each independently represent a hydrogen atom, an alkyl group having 1 to 4 carbon atoms, a cyclohexyl group or a phenyl group; R ₃ represents an alkyl group having 1 to 12 carbon atoms; n is an integer of 0 to 3, and when n is 2 or 3, R ₃ may be the same as or different from each other) to obtain an oil layer containing a cyclohexylidenebisphenol represented by the formula: The oil layer is thermally decomposed in an inert gas atmosphere in a reaction tank to distill off the generated phenols, and the generated cyclohexenylphenols are left in the reaction tank as a reaction residual liquid. General formula (II) characterized in that cyclohexenylphenols are separated

[0018]

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(Wherein R ₁ , R ₂ and R ₃ are the same as described above), and a process for producing cyclohexenylphenols represented by the formula:

[0020]

DESCRIPTION OF THE PREFERRED EMBODIMENTS According to the present invention, as a first aspect, there is provided a method for producing cyclohexenylphenols by pyrolysis of cyclohexylidenebisphenols. In this method, a general formula (I) is used as a starting material.

[0021]

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(Wherein R ₁ and R ₂ each independently represent a hydrogen atom, an alkyl group having 1 to 4 carbon atoms, a cyclohexyl group or a phenyl group, R ₃ represents an alkyl group having 1 to 12 carbon atoms, n is an integer of 0 to 3, and when n is 2 or 3, R ₃ may be the same as or different from each other.).

In the cyclohexylidenebisphenols represented by the general formula (I), R ₁ and R ₂ are each independently a hydrogen atom, an alkyl group having 1 to 4 carbon atoms, a cyclohexyl group or a phenyl group; When it is an alkyl group of 1 to 4, specific examples thereof include a methyl group, an ethyl group, a propyl group and a butyl group. The propyl group and the butyl group may be linear or branched.

R ₃ represents an alkyl group having 1 to 12 carbon atoms, n is an integer of 0 to 3, and when n is 2 or 3, R ₃ may be the same as or different from each other. Is also good.
Therefore, specific examples of R ₃ include a methyl group, an ethyl group, a propyl group, a butyl group, a pentyl group, a hexyl group, a heptyl group, an octyl group, a nonyl group, a decyl group, an undecyl group and a dodecyl group. When the alkyl group has 3 or more carbon atoms, the alkyl group may be linear or branched.

Accordingly, specific examples of such cyclohexylidenebisphenols include, for example, 1,1-bis (4-hydroxyphenyl) -4-isopropylcyclohexane, 1,1-bis (4-hydroxyphenyl)- 4
-N-propylcyclohexane, 1,1-bis (4-hydroxyphenyl) -4-n-butylcyclohexane,
1-bis (4-hydroxyphenyl) -4-n-pentylcyclohexane, 1,1-bis (3-cyclohexyl-
4-hydroxyphenyl) cyclohexane, 1,1-bis (3-methyl-4-hydroxyphenyl) cyclohexane, 1,1-bis (3-phenyl-4-hydroxyphenyl) cyclohexane, 1,1-bis (3,5 -Dimethyl-4
-Hydroxyphenyl) cyclohexane, 1,1-bis (3,5-dimethyl-4-hydroxyphenyl) -4-isopropylcyclohexane, 1,1-bis (3-cyclohexyl-4-hydroxyphenyl) -4-isopropylcyclohexane, Examples thereof include 1,1-bis (4-hydroxyphenyl) -3,3,5-trimethylcyclohexane and 1,1-bis (3-t-butyl-4-hydroxyphenyl) cyclohexane.

According to the method of the present invention, such cyclohexylidenebisphenols are added to a reaction vessel in the presence or absence of a basic catalyst in an atmosphere of an inert gas such as nitrogen gas for 160-160. Heating to a temperature in the range of 270 ° C. and pyrolysis produces cyclohexenylphenols and phenols.

The above basic catalyst is preferably used for accelerating the thermal decomposition of cyclohexylidenebisphenols. Examples of such a basic catalyst include sodium hydroxide, potassium hydroxide, lithium hydroxide and the like. Alkali metal hydroxides, alkali metal carbonates such as sodium carbonate, potassium carbonate and lithium carbonate, alkali metal bicarbonates such as sodium hydrogen carbonate and potassium hydrogen carbonate, and alkaline earth metals such as calcium hydroxide and magnesium hydroxide Examples thereof include hydroxides, alkaline earth metal oxides such as calcium oxide and magnesium oxide. According to the present invention, among these, alkali metal hydroxides such as sodium hydroxide and potassium hydroxide are particularly preferably used.

These basic catalysts are not particularly limited, but are usually in the range of 0.01 to 20 mol%, preferably 0.1 to 10 mol%, based on the starting material cyclohexylidenebisphenols. Used in

In the present invention, during the thermal decomposition of cyclohexylidenebisphenols, cyclohexylidenebisphenols are charged into a reaction vessel, and the inside of the reaction vessel is replaced with an inert gas, for example, nitrogen gas. By charging the reactor, the production of quinones due to undesired side reactions can be suppressed, and the yield of the target product can be increased.

According to the present invention, the thermal decomposition reaction of cyclohexylidenebisphenols is not particularly required to use a reaction solvent at the thermal decomposition temperature if the obtained reaction mixture is a liquid or a slurry. When the viscosity of the obtained reaction mixture is high at the thermal decomposition temperature or when the obtained reaction mixture solidifies, a reaction solvent may be used. The reaction solvent to be used may be any solvent that is inert to the reaction at the thermal decomposition temperature, such as alcohols such as dodecyl alcohol and 2-ethylhexanol, triethylene glycol, tetraethylene glycol, tripropylene glycol and the like. Glycols, phenols such as phenol and alkylphenol, alkylbenzenes such as triisopropylbenzene, alkylnaphthalenes such as diisopropylnaphthalene, and hydrocarbons such as hydrogenated triphenyl.

When such a reaction solvent is used, the solvent is usually used in an amount of 0.01 to 20 times by weight, preferably 0.1 times, the weight of the starting material cyclohexylidenebisphenols.
About 5 times the weight is used.

As described above, in the present invention, the thermal decomposition of cyclohexylidenebisphenols is carried out under the condition that the produced cyclohexenylphenols are not distilled out of the reaction vessel. Therefore, according to the present invention, although it depends on the individual cyclohexylidenebisphenols used as a starting material, the thermal decomposition of cyclohexylidenebisphenols is usually carried out at a temperature in the range of 160 to 270 ° C, preferably 180 to 270 ° C. At a temperature in the range of 220 ° C., under normal pressure or reduced pressure, preferably normal pressure to 0.1 mmH
g, particularly preferably under reduced pressure of 10 to 40 mmHg.

According to the present invention, under such conditions, cyclohexylidenebisphenols are thermally decomposed to form phenols formed by the thermal decomposition reaction (depending on the cyclohexylidenebisphenols used, alkylphenols or phenols). ), And a part or all of the reaction solvent is distilled out of the reaction tank. However, the produced cyclohexenyl phenols formed as a reaction residual liquid in the reaction tank. Remains.

Here, according to the present invention, as described above, the target product cyclohexenylphenol in the reaction residual liquid remaining in the reaction tank can be obtained under the temperature and pressure conditions of thermal decomposition of cyclohexylidenebisphenol. It is relatively stable and thus does not substantially undergo further pyrolysis in the reactor through the pyrolysis reaction. Further, according to the present invention, the phenols formed by the thermal decomposition of cyclohexylidenebisphenols are distilled out of the reaction tank, so that the phenols are added to cyclohexenylphenols, which are the target products formed by the reaction. Thus, regeneration as cyclohexylidenebisphenols, which are starting materials, can also be prevented.

According to the method of the present invention, in the thermal decomposition reaction of cyclohexylidenebisphenols, the desired cyclohexenylphenols are not distilled out of the reaction tank, but are introduced into the reaction tank. The residue is left as a reaction residue containing cyclohexenylphenols, and the target cyclohexenylphenol is separated from the reaction residue. In particular, according to the present invention, as this separation means, the reaction solvent (if a reaction solvent is used) is used as it is, as a crystallization solvent, or after the crystallization solvent is added to the reaction residual liquid, Further, an acid is added to neutralize the reaction residual liquid, and then cyclohexenylphenols are crystallized from the resulting mixture, which is separated and dried, and the desired high-purity cyclohexenylpheno-phenol is obtained. Can be obtained in high yield.

The crystallization solvent may be any solvent that does not react with the cyclohexenylphenol produced in the present invention, and is not particularly limited. Examples thereof include methanol, ethanol, propanol, butanol, and cyclohexanol. Such as aliphatic or alicyclic alcohols and mixtures thereof, acetone, methyl ethyl ketone,
Aliphatic ketones such as methyl isobutyl ketone, aromatic hydrocarbons such as benzene, toluene, xylene, cumene and mesitylene, hexane, cyclohexane, heptane,
Examples thereof include aliphatic or alicyclic hydrocarbons such as methylcyclohexane.

However, among these, aliphatic hydrocarbons having low solubility of the cyclohexenylphenol produced in the present invention and high solubility of impurities produced as a by-product in the thermal decomposition reaction are preferable, and heptane is particularly preferable. preferable.

Such a crystallization solvent is usually used in an amount of 0.2 to 20 times by weight, preferably 0.1 to 5 times by weight, based on cyclohexenylphenol.

In the present invention, the mode of adding the crystallization solvent to the reaction residual liquid is not particularly limited. However, when the thermal decomposition reaction is performed without using the reaction solvent, the thermal decomposition reaction For reasons such as a high freezing point of the product, it is preferable to add the crystallization solvent to the reaction residue at a temperature near its boiling point. Therefore, as a crystallization solvent,
For example, when heptane is used, it is preferably added to the reaction residue at a temperature in the range of 90 to 120 ° C.

As described above, after the crystallization solvent is added to the reaction residue, an acid such as acetic acid, sulfuric acid, phosphoric acid or the like is added to the reaction residue, and the reaction residue is added preferably at a pH of 6 to 10. Neutralize to a range. This is preferable because the reactivity of the target cyclohexenylphenol can be reduced. Then, water was added to the resulting mixture, if necessary, to dissolve the salt formed by neutralization.
Separation and removal of the separated aqueous layer, or without separation and separation, crystallize cyclohexenylphenols, and separate and separate them.
By drying, the desired high-purity cyclohexenylphenols can be obtained.

According to the method of the present invention, as described above, in the thermal decomposition reaction of cyclohexylidenebisphenols, the desired cyclohexenylphenols are not distilled out of the reaction vessel, and It is left as a reaction residue containing cyclohexenylphenols, and then the desired cyclohexenylphenol is separated from the reaction residue to obtain a highly purified product. Therefore, according to the method of the present invention, an apparatus for purification, for example, a purification tank is not required, the process is simple, and the reaction yield is improved. That is, according to the present invention, the yield of the desired cyclohexenylphenol is usually 60 to the starting material cyclohexylidenebisphenol.
About 90 mol%.

As described above, according to the present invention, the general formula (II)

[0043]

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(Wherein R ₁ , R ₂ and R ₃ are the same as described above).

Accordingly, specific examples of such cyclohexenyl phenols include 4- (1-cyclohexenyl) phenol, 4- (4-methyl-1-cyclohexenyl) phenol, 4- (4-ethyl-1- Cyclohexenyl) phenol, 4- (4-n-propyl-1-cyclohexenyl) phenol, 4- (4-isopropyl-1-cyclohexenyl) phenol, 4- (4-n-
Butyl-1-cyclohexenyl) phenol, 4- (4
-N-pentyl-1-cyclohexenyl) phenol,
4- (4-n-hexyl-1-cyclohexenyl) phenol, 4- (4-n-hexyl-1-cyclohexenyl) phenol, 4- (4-n-octyl-1-cyclohexenyl) phenol, 4- (4-n-dodecyl-1
-Cyclohexenyl) phenol, 4- (4-cyclohexyl-1-cyclohexenyl) phenol, 4- (1
-Cyclohexenyl) -2-cyclohexylphenol, 4- (1-cyclohexenyl) -2-methylphenol, 4- (1-cyclohexenyl) -2-phenylphenol, 4- (1-cyclohexenyl) -2,6 -Dimethylphenol, 4- (4-isopropyl-1-cyclohexenyl) -2,6-dimethylphenol, 4- (3,3,
5-trimethyl-1-cyclohexenyl) phenol,
4- (4-n-butyl-1-cyclohexenyl) -2-
Cyclohexylphenol, 4- (1-cyclohexenyl) -2-t-butylphenol and the like can be mentioned.

In the method of the present invention, the cyclohexylidenebisphenol used as a starting material is obtained by a condensation reaction of an appropriate phenol with a cyclohexanone as described in JP-A-2000-159711. Obtainable.

Therefore, according to the present invention, as another aspect, an appropriate phenol and cyclohexanone are condensed to form cyclohexylidenebisphenols, and the obtained reaction is isolated without isolation. The product as it is, or, if necessary, unreacted phenols or, in some cases, unreacted cyclohexanones are removed by distillation, and this is preferably thermally decomposed in the presence of a basic catalyst. As described above, cyclohexenylphenols can be separated from the reaction residual liquid in the reaction tank containing the produced cyclohexenylphenols to obtain the desired high-purity cyclohexenylphenols.

That is, the cyclohexylidenebisphenol represented by the general formula (I) is a compound represented by the general formula (III)

[0049]

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(Wherein, R ₁ and R ₂ each independently represent a hydrogen atom, an alkyl group having 1 to 4 carbon atoms, a cyclohexyl group or a phenyl group) and a phenol represented by the general formula (IV)

[0051]

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(Wherein R ₃ represents an alkyl group having 1 to 12 carbon atoms, n is an integer of 0 to 3, and when n is 2 or 3, R ₃ may be mutually the same or different. May be obtained by dehydration-condensation with the cyclohexanone represented by the formula (1) in the presence of an acid catalyst.

In the phenols represented by the general formula (III) and the cyclohexanones represented by the general formula (IV), R ₁ , R ₂ , R ₃ and n are the same as described above. Therefore, the phenols include, for example, phenol, 2-methylphenol, 2-ethylphenol,
-Propylphenol, 2-isobutylphenol, 2,
6-dimethylphenol, 2,6-diethylphenol,
Examples thereof include 2,6-dipropylphenol, 2,6-di-t-butylphenol, 2-cyclohexylphenol, and 2-cyclohexyl-5-dimethylphenol.

Similarly, the cyclohexanone includes, for example, cyclohexanone, 4-methylcyclohexanone, 4-ethylcyclohexanone, 4-n-propylcyclohexanone, 4-isopropylcyclohexanone, 4-n-butylcyclohexanone, 4-t-butyl Cyclohexanone, 4-n-pentylcyclohexanone, 4-n-hexylcyclohexanone, 4-n-heptylcyclohexanone, 4-n-octylcyclohexanone, 4-n-decylcyclohexanone, 4-n-dodecylcyclohexanone, 4-cyclohexylcyclohexanone, 3 , 5-dimethylcyclohexanone, 3,3,5-trimethylcyclohexanone, and the like.

In the production of cyclohexylidenebisphenols by condensation of the above-mentioned phenols with the above-mentioned cyclohexanone, the phenol is usually, but not limited to, a phenol having a theoretical value based on 1 mol part of the cyclohexanone. (2 mol parts) or more, and particularly in the range of 4 to 10 mol parts per 1 mol part of cyclohexanone. When the amount of the phenol is less than 2 parts by mol per 1 part by mol of the cyclohexanone, the production ratio of undesired by-products increases, and the yield of the desired cyclohexylidenebisphenol decreases.
However, if more than 10 parts by mole of phenol is used per 1 part by mole of cyclohexanone, a large amount of unreacted phenol remains, which is disadvantageous from the viewpoint of reaction economy, and lowers production efficiency. I do.

The acid catalyst used for the condensation of the above phenols with the above cyclohexanone is not limited. For example, concentrated hydrochloric acid, hydrogen chloride gas, 60 to 98% sulfuric acid, 85% phosphoric acid, methane sulfone Acids, ion exchange resins and the like are used.

The phenols and the cyclohexanone condense even in the presence of only such an acid catalyst. However, depending on the cyclohexanone used, a co-catalyst such as an alkyl mercaptan may be used together with the acid catalyst. May be preferred. As such a co-catalyst, an alkyl mercaptan having 1 to 12 carbon atoms is particularly preferable. Such an alkyl mercaptan is usually used in a range of 0.1 to 10% by weight based on cyclohexanone.

When the phenols used are solid at ordinary temperature, preferably, for example, aliphatic alcohols or aromatic hydrocarbons (eg, toluene, etc.) are used as a reaction solvent in the condensation reaction with cyclohexanone. Used.

The condensation reaction between the above phenols and the above cyclohexanone is not particularly limited.
When the reaction temperature is too low, the reaction rate is too slow for practical use. On the other hand, when the reaction temperature is too high, an undesired side reaction occurs and the yield of the desired cyclohexylidenebisphenol decreases. Therefore, the condensation reaction between the phenols and the cyclohexanone is preferably 20 to 20.
It is carried out at a temperature of 80 ° C, preferably 30-60 ° C.

The condensation reaction between the above phenols and the above cyclohexanone can be monitored by liquid chromatography analysis or gas chromatography analysis, and the unreacted cyclohexanone disappears and the desired cyclohexylidenebisphenol increases. The point at which is no longer observed may be the end point of the reaction.

Therefore, after completion of the reaction, the obtained reaction mixture was neutralized with an aqueous alkali solution, and the aqueous layer was separated and removed.
The obtained cyclohexenyl phenols can be obtained by subjecting the obtained oil component to thermal decomposition in the same manner as described above, preferably in the presence of a basic catalyst.

That is, as described above, when an oil containing cyclohexylidenebisphenols as a reaction product is obtained, and a solvent is used in the condensation reaction between the phenols and cyclohexanone, the oil is preferably converted from the oil to the solvent. Is distilled off. Thus, after removing the solvent from the oil,
This oil component consists of the produced cyclohexylidenebisphenols, the unreacted phenols used in excess, and the reaction by-products.

Thus, the oil is cyclohexylylated at a temperature in the range of 160 to 270 ° C., preferably in the presence of a basic catalyst, in an atmosphere of an inert gas such as nitrogen gas, under reduced pressure of normal pressure to 10 mmHg. By heating denbisphenols to thermally decompose cyclohexylidenebisphenols in oil, low boiling products such as phenols (alkylphenols or phenols) formed are distilled out of the reaction tank, and The product cyclohexenyl phenol is allowed to remain in the reaction tank as a reaction residual liquid, and thereafter, in the reaction tank, the target cyclohexenyl phenol is separated from the obtained reaction residual liquid in the reaction tank as described above. High purity cyclohexenylphenols can be obtained in high yield.

According to the method of the present invention, starting from phenol and cyclohexanone, the obtained reaction mixture is thermally decomposed as it is without separating the obtained cyclohexylidenebisphenols. The desired cyclohexenylphenols are separated from the reaction residue to obtain a high-purity product. Therefore, according to such a method, thermal decomposition of cyclohexylidenebisphenols generated by the condensation reaction of phenol and cyclohexanone and separation of cyclohexenylphenols generated by the thermal decomposition are performed in a single reaction tank. And thus no equipment is required for purification,
The process is simple, and a high-purity product can be obtained in a high yield.

[0065]

EXAMPLES The present invention will be described below with reference to examples.
The present invention is not limited by these examples.

[0066]

Example 1 (Synthesis of 4- (4-n-heptyl-1-cyclohexenyl) phenol) A 1000 ml four-necked flask equipped with a thermometer, a stirrer, a nitrogen gas injection tube and a condensation tube was used as a reaction tank. Used and 1,1-bis (4
-Hydroxyphenyl) -4-n-heptylcyclohexane was charged, and the inside of the reaction vessel was replaced with nitrogen gas. The temperature was raised, and then the pressure inside the reaction vessel was reduced to 30 mmHg, and a thermal decomposition reaction was carried out for 4 hours while distilling off the generated phenol, to obtain 94 g of a distillate and a reaction residue 272 in the reaction vessel.
g was obtained.

After completion of the reaction, the reaction residue was analyzed by high performance liquid chromatography (HPLC). As a result, 86% by weight of the reaction residue was 4- (4-n-heptyl-1).
-Cyclohexenyl) phenol.

Next, heptane 544 was added to the reaction residue.
g and 1.3 g of glacial acetic acid, 136 g of water were further added, and the mixture was cooled to 25 ° C. Thus, the precipitated crystals were separated by filtration and dried under reduced pressure to obtain 220 g of the objective 4- (4-n-heptyl-1-cyclohexenyl) phenol as white needle crystals. Purity 99.3%, melting point 118.5 ° C
Met. The yield based on the raw material 1,1-bis (4-hydroxyphenyl) -4-n-heptylcyclohexane was 80.7%.

[0069]

Example 2 (Synthesis of 4- (4-ethyl-1-cyclohexenyl) phenol) A 1000 ml four-necked flask equipped with a thermometer, stirrer, gas injection tube and dropping funnel was used as a reaction vessel. After charging 564 g of phenol, hydrogen chloride gas was blown into the flask until saturation.

Then, the temperature was raised to 50 ° C., and a mixture of 126 g of 4-ethylcyclohexanone and 189 g of toluene was added dropwise over 2 hours. Thereafter, while maintaining the same temperature, the reaction was further continued for 6 hours with stirring. Done.

After the completion of the reaction, 16% was added to the obtained reaction mixture.
An aqueous sodium hydroxide solution was added to seal. Thereafter, toluene was additionally added, and the aqueous layer was separated and separated from the obtained mixture, and further washed twice with water to obtain a target 1,1-bis (4-hydroxyphenyl) -4-ethylcyclohexane. An oily layer containing was obtained.

Next, after replacing the dropping funnel of the reaction tank having the oil layer with a condenser tube, the inside of the reaction tank was replaced with nitrogen, and 1.4 g (0.017 mol) of a 48% aqueous sodium hydroxide solution was added.
The temperature was raised to 180 ° C. under a nitrogen stream to distill toluene and excess phenol. After that, at a temperature of 200 ° C and a pressure of 30
A thermal decomposition reaction was performed for 6 hours while distilling off the generated phenol under the condition of mmHg to obtain 94 g of a distillate and 202 g of a reaction residual liquid in the reaction vessel.

After completion of the reaction, the reaction residue was analyzed by high performance liquid chromatography (HPLC). As a result, 88% by weight of the residue was 4- (4-ethyl-1-cyclohexenyl) phenol.

Next, heptane 404 was added to the reaction residue.
g and 1.0 g of glacial acetic acid, and further, 202 g of water.
Cooled to 25 ° C. Thus, the precipitated crystals are filtered off,
After drying under reduced pressure, 168 g of the desired 4- (4-ethyl-1-cyclohexenyl) phenol was obtained as white needle crystals. The purity was 98.7% and the melting point was 117.7 ° C.
The yield based on the raw material 4-ethylcyclohexanone was 83.2%.

[0075]

Example 3 Synthesis of 4- (1-cyclohexenyl) phenol In Example 1, 1,1-bis (4-hydroxyphenyl) -4-heptylcyclohexane was replaced with 1,1-bis (4 -Hydroxyphenyl) cyclohexane, except that 268 g was used.
Desired 4- (1-cyclohexenyl) phenol 1
10 g were obtained as white needle crystals. The purity was 97.2% and the melting point was 121.1 ° C. The raw material 1,1-bis (4-
The yield based on (hydroxyphenyl) cyclohexane is 6
3%.

[0076]

Example 4 (Synthesis of 4- (4-propyl-1-cyclohexenyl) phenol) In Example 1, 1,1-bis (4-hydroxyphenyl) -4-heptylcyclohexane was replaced with 1,1 In the same manner as in Example 1 except that 310 g of -bis (4-hydroxyphenyl) -4-propylcyclohexane was used, 164 g of the intended 4- (4-propyl-1-cyclohexenyl) phenol was obtained as white needle-like crystals. As obtained. Purity 99.2%, melting point 11
6.7 ° C. The yield based on the raw material 1,1-bis (4-hydroxyphenyl) -4-propylcyclohexane was 76%.

[0077]

Example 5 (Synthesis of 4- (4-butyl-1-cyclohexenyl) phenol) In Example 1, 1,1-bis (4-hydroxyphenyl) -4-heptylcyclohexane was replaced with 1,1 -Bis (4-hydroxyphenyl)
Except for using 324 g of -4-butylcyclohexane,
In the same manner as in Example 1, the desired 4- (4-butyl-
182 g of 1-cyclohexenyl) phenol were obtained as white needle-like crystals. The purity was 98.3% and the melting point was 126.6 ° C. The yield based on the raw material 1,1-bis (4-hydroxyphenyl) -4-butylcyclohexane was 79%.
Met.

[0078]

Example 6 (Synthesis of 4- (4-pentyl-1-cyclohexenyl) phenol) In Example 1, 1,1-bis (4-hydroxyphenyl) -4-heptylcyclohexane was replaced with 1,1 In the same manner as in Example 1 except that 338 g of -bis (4-hydroxyphenyl) -4-pentylcyclohexane was used, 198 g of the objective 4- (4-pentyl-1-cyclohexenyl) phenol was obtained in the form of white needle crystals. As obtained. Purity 99.1%, melting point 12
3.0 ° C. The yield based on the raw material 1,1-bis (4-hydroxyphenyl) -4-pentylcyclohexane was 81%.

[0079]

According to the present invention, the phenols formed distill out of the reaction vessel, but the cyclohexenylphenols formed remain under the mild reaction conditions such that they remain in the reaction vessel. Then, the desired cyclohexenyl phenols are separated from the reaction residue remaining in the reaction vessel in this manner. Therefore, according to the present invention, high-purity alkenylphenols can be obtained in high yield without using complicated and expensive production equipment.

 ────────────────────────────────────────────────── ─── Continuing on the front page (72) Inventor Yoichiro Isoda 2-115, Kozaiga, Wakayama-shi, Wakayama Pref. Inside the Research Institute, Honshu Chemical Industry Co., Ltd. No. 5 115 Inside Honshu Chemical Industry Co., Ltd. (72) Inventor Hiroyuki Kojima 2-115 Kozaiga, Wakayama-shi, Wakayama Prefecture Honshu Chemical Industry Co., Ltd. FC52 FE13 4H039 CA40 CD10 CF30 CL25

Claims (2)

[Claims] [Claim 1] General formula (1) (Wherein, R ₁ and R ₂ each independently represent a hydrogen atom, an alkyl group having 1 to 4 carbon atoms, a cyclohexyl group or a phenyl group; R ₃ represents an alkyl group having 1 to 12 carbon atoms;
n is an integer of 0 to 3, and when n is 2 or 3, R ₃ may be the same or different. ) Is thermally decomposed in an inert gas atmosphere in a reaction vessel to distill off the generated phenols, and the generated cyclohexenylphenols as a reaction residual liquid in the reaction vessel. Wherein cyclohexenylphenols are separated from the reaction residual liquid, and characterized by the general formula (II): (Wherein R ₁ , R ₂ and R ₃ are the same as described above). 2. A compound of the general formula (III) (Wherein, R ₁ and R ₂ each independently represent a hydrogen atom, an alkyl group having 1 to 4 carbon atoms, a cyclohexyl group or a phenyl group) and a phenol represented by the general formula (IV): (Wherein, R ₃ represents an alkyl group having 1 to 12 carbon atoms;
Is an integer of 0 to 3, and when n is 2 or 3, R ₃ may be the same or different. ) Is dehydrated and condensed in the presence of an acid catalyst, the resulting reaction mixture is neutralized with an alkali, and the aqueous layer is removed by liquid separation to obtain a compound of the general formula (I) ] (Wherein, R ₁ and R ₂ each independently represent a hydrogen atom, an alkyl group having 1 to 4 carbon atoms, a cyclohexyl group or a phenyl group; R ₃ represents an alkyl group having 1 to 12 carbon atoms;
n is an integer of 0 to 3, and when n is 2 or 3, R ₃ may be the same or different. ) Is obtained, and the oil layer is thermally decomposed in an inert gas atmosphere in a reaction vessel to distill off the produced phenols, and to form the cyclohexenylphenols produced. Is left in the reaction tank as a reaction residual liquid, and cyclohexenylphenols are separated from the reaction residual liquid. (Wherein R ₁ , R ₂ and R ₃ are the same as described above).