JPS61271236A - Production of unsymmetrical bisphenol - Google Patents

Abstract

PURPOSE:To obtain in high purity in high yield the titled compound useful as a raw material for a polymer, by adding a meta-isopropenylphenol diluted with a hydrocarbon solvent little by little to a hydrogen chloride-containing phenol, prescribing a molar ratio of the raw materials, and reacting them at a specific temperature. CONSTITUTION:In obtaining 2-(3-hydroxyphenyl)-2-(4-hydroxyphenyl)propane by reacting meta-isopropenylphenol with phenol, the reaction is carried out at about 20- about 60 deg.C, preferably 35-50 deg.C while adding little by little meta- isopropenylphenol which is diluted with >=3 times, preferably 5-10 times as much as a hydrocarbon solvent by volume so as to make a molar ratio of meta-iospropenylphenol/phenol of <=0.07, preferably 0.01-0.05 to an aextremely excess amount of phenol containing hydrogen chloride as a catalyst. The titled compound having 120-122 deg.C, preferably 121-122 deg.C melting point is easily obtained by this method.

Description

Detailed Description of the Invention [Industrial Application Field] The present invention relates to 2-(3-hydroxyphenyl)-2-(4-hydroxyphenyl), which is useful as a raw material for polymeric materials such as polycarbonate and epoxy resin. The present invention relates to a method for producing propane (hereinafter abbreviated as p-bis A).

More specifically, the present invention relates to a method for producing bis-A with few impurities in a high yield from metaisopropenylphenol and phenol.

The present invention also relates to high purity p-bis A.

[Conventional technology]

As a manufacturing method for m, p-bis A, JP-A-55-9
Methods proposed in the specification of Japanese Patent No. 8126 and the specification of US Pat. No. 4,460,798 are known. Among these methods, the method using 3-hydroxyphenyldimethylcarbinol and phenol as raw materials has the disadvantage that water accumulates as the reaction progresses, reducing the effect of the acid catalyst. In order to avoid this, it is necessary to replenish a considerable amount of acid catalyst or to use a large amount of acid catalyst from the beginning, which is not a preferable method. The former publication also describes a method for reacting metaisopropenylphenol with phenol, but the method taught there has a low yield of m, p-bis A, probably because of the large amount of by-products. The m+1)-bis A shown in both publications has a melting point of 97 to 98°C, and according to the findings of the present inventors, it is assumed that it contains some impurities. When a material containing such impurities is used as a raw material for a polymer, for example, problems arise such that the molecular weight cannot be increased or the desired properties cannot be obtained.

[Problem that the invention seeks to solve]

In view of the current situation, the present inventors have made myp containing few impurities.
-As a result of studying methods for economically producing BisA with good yield, the following method was discovered. It is therefore an object of the present invention to provide an improved method for producing m+p-bisA. Another object of the present invention is to obtain high purity m, p
- To provide service A.

[Means for Solving the Problems] The present invention provides that when reacting methanopropenylphenol with phenol, the molar ratio of metaisopropenylphenol/phenol in a large excess of phenol containing hydrogen chloride is normally KO, about 20 to about 50°C while adding a small amount of metaisopropenylphenol diluted with 3 times the volume or more of a hydrocarbon solvent so that the temperature is 0.07 or less.
The present invention relates to a method for producing m,p-bis A, characterized in that the reaction is carried out at a temperature of .

The present invention also provides m having a melting point in the range of 120 to 122°C,
Regarding p-bisA.

In the present invention, hydrogen chloride is used as a catalyst.

Hydrogen chloride may be used in gaseous form or in the form of an aqueous solution. If a catalyst other than hydrogen chloride is used, such as an ion exchange resin, phosphoric acid, sulfuric acid, silica alumina, etc., it is not preferable because a considerable amount of methanepropenylphenol dimer, which is difficult to separate from smyp-bisA, is produced as a by-product. .

In the present invention, a hydrocarbon solvent is also used during the reaction. For example, aliphatic hydrocarbons such as n-hexane, n-hebutane, cycloaliphatic hydrocarbons such as cyclopenkune, cyclohexane, aromatic hydrocarbons such as benzene, toluene, xylene, ethylbenzene, cumene, chloroform, chlorobenzene. Halogenated hydrocarbons such as
Preferably, 9 parts of toluene are used. This-
When the reaction is carried out without using a hydrocarbon solvent,
The by-product of metaisopropenylphenol dimer increases, the recovery rate of m+p-bisA decreases significantly, and the purity and color of the obtained product are poor.

In addition, when there is a particularly large amount of dimer by-products, there are drawbacks such as a high viscosity liquid and the recovery of crystalline m and p-bis A.

The reaction is carried out by adding methanopropenylphenol diluted with a hydrocarbon solvent in portions into the phenol containing hydrogen chloride.

The phenol may be diluted in advance with a hydrocarbon solvent. In this case, using a large amount of phenol will only increase the load on the subsequent separation process and will not provide any advantage, so even when diluting, it is about 172 times the volume of phenol or less, preferably 1/4 times the volume or less. should be kept at a minimum. The amount of phenol to be used is a large stoichiometric excess, and is usually in the range of 3 times or more, preferably 5 to 10 times, by mole of the added metaisopropenylphenol.

On the other hand, when hydrogen chloride is used in gaseous form, it is used by absorbing pressurized liquefied gas into a phenol solution under atmospheric pressure.

When used in the form of an aqueous solution, it is appropriate to use a molar ratio of 0.001 to 0.05 mole relative to metaisopropenylphenol in a solution of about 15 to 35 mol. It is sufficient to charge hydrogen chloride to the reaction system at the beginning, but it can also be added during the reaction if desired. Furthermore, although it is sufficient to add phenol only at the beginning, it can also be added during the reaction.

One of the particularly important points in the present invention is that metaisopropenylphenol diluted with a hydrocarbon solvent of 3 times or more by volume, preferably 5 to 10 times by volume, is added to the methanopropenylphenol/phenol (methanepropenylphenol/phenol) in the reaction system. molar ratio) is always below 0.07, preferably between 0.01 and 0.07.
The reaction is to be carried out while adding small amounts at a time so that the amount is 0.05. The addition here may be continuous or intermittent.

Furthermore, there is no problem in continuing the reaction even after the addition is completed.

If the dilution of impropenylphenol is smaller than the above range, or if the molar ratio of impropenylphenol/phenol in the reaction system is larger than the range above, side reactions, especially low polymerization of impropenylphenol, will be ignored. It cannot be done, so it must be avoided.

Also, the reaction temperature should be 20 to 60°C, preferably 35 to 50°C. If the reaction temperature is lower than the above range, the reaction rate will be slow, and if the reaction temperature exceeds 60°C, the amount of side reaction products will increase, which is undesirable.

Thus, according to the reaction of the present invention, since the amount of side reaction products, particularly multimers of metaisopropenylphenol, is small, purification is easy and a highly pure product can be obtained.

For example, if the reaction product is distilled under reduced pressure to sequentially remove hydrogen chloride, a hydrocarbon solvent, and phenol, and then recrystallized using an aromatic hydrocarbon, highly pure mtp-bis A can be isolated. can do. According to the invention, the melting point is 12
0 to 122°C, usually 121 to 122°C om, p-bis A
can be easily obtained. Such high-purity m, p-bis A is suitable as a raw material for polycarbonate, epoxy resin, and the like.

Examples are shown below.

Example 1 Solution A was prepared by adding 10 d of 65% commercially available special grade hydrochloric acid to 1300 g (13.8 mQl) of phenol.

On the other hand, 120 g of metaisopropenylphenol (0,8
A mixed solution (9 mol) dissolved in hexay800at (
Solution B) was prepared. While keeping Solution A at 50° C. and stirring well, Solution B was added dropwise over 3 hours to react. One hour after the completion of the dropwise addition, the product was analyzed by gas chromatography, and it was found that all of the methanopropenylphenol had reacted! The selectivity of tsmyp-bisA was 92.4 (based on metaisopropenylphenol). After removing hexane and phenol by distillation, crystallization was repeated twice with toluene and dried under reduced pressure at 30°C for a day and night. M,p-bis A with a high purity of over 999% was obtained as pure white crystals. . Measure the melting point using a conventional method (for example, using the Mettler Melting Point Analyzer FP-61
The temperature was 121 to 122°C at a temperature increase rate of 1°C/-).

Example 2 Dissolve 1300 g (13.8 mol) of phenol,
After keeping the temperature at 0°C, hydrogen chloride gas was bubbled for 20 minutes to saturate the phenol solution with hydrogen chloride.
The supply of hydrogen chloride gas was stopped, and 120 g (0.89 mol) of metaisopropenylphenol was added to it for 800 d.
A solution dissolved in toluene was added dropwise over 2 hours to cause a reaction. After reacting for an additional hour after the completion of the dropwise addition, the contents were analyzed by gas chromatography, and the entire amount of metaisopropenylphenol was reacted, resulting in a concentration of 1 mtp-
Bis A selectivity (methinpropenylphenol standard)
was 91%. According to Example 1, after removing toluene and phenol, crystallization with toluene resulted in 9
m, p-bis A with a purity of 99% or more was obtained. The melting point was 121-122°C.

Comparative Example 1 In Example 1, when preparing liquid B, n-hexane 70
When 500 g of phenol was used in addition to 0d and reacted in the same manner as in Example 1, the entire amount of methanopropenylphenol reacted, but sILp-
The selectivity for bisA was 64.4%, O,m-bisA was 4.4%, and the selectivity for metaisopropenylphenol dimer was 31.2% (methisopropenylphenol dimer).
/+44). After n-hexane and phenol were removed from this reaction solution, it was crystallized with toluene, but high purity m, p-bis A was not precipitated and only a highly viscous slurry was obtained.

Comparative Example 2.3.4 In Example 1, instead of using hydrochloric acid as a catalyst, phosphoric acid (Comparative Example 2), strong acid type ion exchange resin Amberlith)-15 (Comparative Example 6) and silica alumina (Comparative Example 4) were used. , N631L manufactured by JGC Chemical Co., Ltd.) was used.

The results are shown in the table in comparison with Example 1.

Table 1゜Comparative Example 5 120g (0.89m01) of metaisopropenylphenol to 1300g (13.8g) phenol (liquid A)
After mixing a solution (solution B) in which 10,100O of toluene was dissolved, the mixture was kept at 50°C and heated for 3 minutes without stirring.
10 mj of 5-thihydrochloric acid was added dropwise over about 1 hour. The reaction was continued for an additional hour.

When the reaction solution was analyzed by gas chromatography, it was found that the entire amount of metaisopropenylphenol had reacted.
The selectivity of m, p-bis A was 82.0%, and the ratio of acetic acid and improbenyl phenyl dimer was 13.5%. When recrystallized in the same manner as in Example 1, 9m, p-
The purity of Bis A is 98.2% and the melting point is 116-118℃.
Met.

Claims (2)

[Claims] (1) When reacting metaisopropenylphenol and phenol, make sure that the metaisopropenylphenol/phenol (molar ratio) is always 0.07 or less in a large excess of phenol containing hydrogen chloride by at least 3 times the volume. 2-(3-hydroxyphenyl)-2, characterized in that the reaction is carried out at a temperature of about 20 to about 60°C while adding metaisopropenylphenol diluted with a hydrocarbon solvent little by little.
- A method for producing (4-hydroxyphenyl)propane. (2) High purity 2- with a melting point in the range of 120 to 122°C
(3-hydroxyphenyl)-2-(4-hydroxyphenyl)propane.