JPS599534B2 - Method for producing bis(3,5-dihydroxymethyl-4-hydroxyphenyl) alkanes - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention provides bis(3,5-dihydroxymethyl-4-
The present invention relates to a method for producing (hydroxyphenyl) alkanes.

More specifically, bis(3.5 -Relates to a method for producing dihydroxymethyl-4-hydroxyphenyl)alkanes.Bis(3,5-dihydroxymethyl-4-hydroxyphenyl)alkanes are more suitable for novolac type phenolic resins than conventional solid resols and hexamines. It has recently attracted attention due to its excellent curing effect as a compounding agent, epoxy resin raw material, or its curing agent. Conventionally, bis(3,5-dihydroxymethyl- Many methods for producing 4-hydroxyphenyl) alkanes have been reported in the literature.

In both of these methods, phenols and formaldehyde are reacted in the presence of a basic catalyst containing an alkali metal or alkaline earth metal, but they do not require the use of polymer compounds or trihydroxymethylated or dihydroxymethylated by-products. High quality bis(3,5-dihydroxymethyl-4-hydroxyphenyl) alkanes cannot be produced because of the large amount of raw materials and the difficulty of separating and removing these by-products from the product. In particular, when bis(4-hydroxyphenyl)alkanes such as 1,1-bis(4-hydroxyphenyl)ethane and 2,2-bis(4-hydroxyphenyl)propane are used as the raw material phenols. This tendency is large for the product bis(3,5-dihydroxymethyl-4-
Hydroxyphenyl)alkanes contain a large amount of the above-mentioned by-products which are difficult to purify and separate, and are only obtained as low-purity, viscous liquid products. These low-quality, liquid bis(3,5-dihydroxymethyl-4-hydroxyphenyl) alkanes can be made into novolak-type phenolic resins, epoxy resins for casting, epoxy resins for powder coating, etc. When blending into a solid base resin,
In addition to disadvantages such as poor workability and low curing effect, it also has disadvantages such as discoloration or deterioration due to poor stability when stored. The present inventors have developed screws (3 and 5
- Dihydroxymethyl-4-hydroxyphenyl) alkanes As a result of investigating a method to improve the above-mentioned drawbacks, it was found that the raw material bis(4-hydroxyphenyl) alkanes were reacted with formaldehyde under specific conditions. The present inventors have discovered that high quality and crystalline bis(3,5-dihydroxymethyl-4-hydroxyphenyl) alkanes can be obtained by acid precipitation after the oxidation process, and that the above object can be achieved, and the present invention has been achieved. did.

That is, the present invention provides bis(4-hydroxyphenyl)methane, 1,1-bis(4-hydroxyphenyl)ethane and 2,2-bis(4-hydroxyphenyl)ethane in the presence of a basic catalyst in an aqueous solution. The corresponding bis(3,5-dihydroxymethyl-4
- A method for producing hydroxyphenyl)alkanes, in which an alkali metal hydroxide is used as a basic catalyst in an amount of 1.6 to 2.5 grams of alkali metal atoms per mole of the bis(4-hydroxyphenyl)alkanes. formaldehyde is used in the range of 3.7 to 4.3 mol per mol of the bis(4-hydroxyphenyl)alkane, and the reaction is carried out at a temperature in the range of 0 to 55°C. bis(3,5-dihydroxymethyl-4-
This is a method for producing hydroxyphenyl) alkanes.

Bis(4-
The hydroxyphenyl) alkanes are selected from the group consisting of bis(4-hydroxyphenyl)methane, 1,1 bis(4-hydroxyphenyl)ethane and 2,2-bis(4-hydroxyphenyl)propane. There is one type.
Among these bis(4-hydroxyphenyl) alkanes, it is preferable to use 1,1-bis(4-hydroxyphenyl)ethane or 2,2-bis(4-hydroxyphenyl)propane. In addition to formaldehyde, examples of formaldehyde used as a raw material in the method of the present invention include formalin, which is an aqueous solution thereof, and paraformaldehyde, which is a polymer of formaldehyde and can easily produce formaldehyde. .

Among these, formalin is preferably used in the method of the present invention. In order to produce high-quality crystallized bis(3,5-dihydroxymethyl-4-hydroxy) alkanes, the proportion of formaldehyde used should be approximately 1 mole of the bis(4-hydroxyphenyl) alkanes. It is necessary that the amount is in the range of 3.7 to 4.3 mol, and particularly preferably in the range of 3.8 to 4.2 mol. If the ratio of formaldehyde to 1 mole of bis(4-hydroxyphenyl)alkanes is greater than 4.3 moles, the amount of by-products of polymer compounds will increase, and if it is less than 3.7 moles, dihydroxymethylated products and trihydroxymethyl In either case, the product becomes a viscous liquid. The basic catalyst used in the process of the invention is an alkali metal hydroxide.

Specifically, lithium hydroxide, sodium hydroxide, potassium hydroxide, etc. can be exemplified. When these alkali metal hydroxides react with the bis(4-hydroxyphenyl)alkanes, they form alkali metal salts of bis(4-hydroxyphenyl)alkanes, so they are added to the reaction system with a basic catalyst and The reaction substrate bis(4
-hydroxyphenyl) alkanes. In order to produce high-quality crystallized bis(3,5-dihydroxymethyl-4hydroxy) alkanes, the proportion of these alkali metal hydroxides should be the same as that of the bis(4-hydroxyphenyl) alkanes. It is necessary that the alkali metal atoms be in the range of 1.6 to 2.5 gram atoms per mole, and preferably in the range of 1.7 to 2.1 gram atoms. Here, when an alkali metal salt of bis(4-hydroxyphenyl)alkanes is used as a basic catalyst and a reaction substrate, the alkali metal salt of bis(4-hydroxysoenyl)alkanes is It shall be calculated by including the amount of each of the hydroxide and the bis(4-hydroxyphenyl) alkanes used. Even if the proportion of alkali metal hydroxide used is less than 1.6 g atoms or greater than 2.5 g atoms per mole of bis(4-hydroxyphenyl) alkanes, the product will be low. It becomes a pure and viscous liquid. In the present invention, the condensation reaction of bis(4-hydroxyphenyl)alkanes and formaldehyde in the presence of a basic catalyst is carried out in an aqueous solvent. ) Other water-soluble organic solvents, such as alcohols, ketones, or nitriles, may be mixed and used as necessary within a range that does not impair the solubility of the alkanes.

The proportion of the solvent used in the reaction is usually 1 to 5 times, preferably 2 to 4 times, the weight ratio of the bis(4-hydroxyphenyl) alkanes. In the present invention, in order to produce high-quality crystallized bis(3,5-dihydroxymethyl-4-hydroxyphenyl) alkanes, a condensation reaction between bis(4-hydroxyphenyl) alkanes and formaldehyde is carried out. It is necessary to carry out the process at a temperature in the range of 0 to 55°C, and it is particularly preferable to carry out the process at a temperature in the range of 30 to 50°C. Even if the temperature during the reaction is no longer higher than 50°C or lower than 0°C, the resulting product will contain many various by-products,
It becomes a low-quality, viscous liquid. In carrying out the method of the present invention, a method of stirring a mixture consisting of 1-bis(4-hydroxyphenyl)alkanes, formaldehyde, a basic catalyst and a solvent at the above temperature, 2-bis(4-hydroxyphenyl)alkanes , A method of continuously or intermittently supplying formaldehyde to a mixture consisting of a basic catalyst and a solvent under stirring, 3. A method of supplying formaldehyde to a mixture consisting of a basic catalyst and a solvent under stirring, bis(4-hydroxyphenyl)alkanes, a basic catalyst and a method of continuously or intermittently supplying a mixture consisting of a basic catalyst and a solvent as needed; Any method such as a continuous or intermittent supply method can be adopted.

Among these methods, it is preferable to adopt method 1. In the present invention, bis(3,5-dihydroxymethyl-4-
Hydroxyphenyl) alkanes exist as their alkali metal salts, but the amount of basic catalyst used is
When the amount is less than the equivalent amount of 4-hydroxyphenyl)alkanes, it exists as bis(3,5-dihydroxymethyl-4-hydroxyphenyl)alkanes.

The mixture after the completion of the reaction may be directly subjected to acid precipitation, or the mixture after the completion of the reaction may be isolated by filtration, concentration, or other conventional methods, and further acid precipitation may be carried out. High quality screws (3.
5-dihydroxymethyl (4-hydroxyphenyl) alkanes are obtained as powdered crystals. Screw (3.5
-Dihydroxymethyl-4-hydroxyphenyl) Acid precipitation of the alkali metal salt of the alkane is carried out according to a conventional method. Sulfuric acid, hydrochloric acid, phosphoric acid, etc. are usually used for acid precipitation, and are generally used in a diluted state. The temperature during acid precipitation is usually 0 to 40°C, preferably 15 to 3°C.
It is 0°C. Next, the method of the present invention will be specifically explained using examples.

Example 1 After replacing the inside of a separable flask with an internal volume of 31 equipped with a condenser, a stirrer, and a dropping load with nitrogen gas, 325 tons of 37% by weight formalin was placed inside the flask.
(contains 4 moles of formaldehyde), 2●2-bis(4-
228 t (1 mol) of (hydroxyphenyl)propane and 340 f of water were added, and a mixed solution consisting of 80 y (2 mol) of sodium hydroxide and 80 t of water was added dropwise from a dropwise load over a period of 10 minutes.

After the dropwise addition was completed, the temperature was raised to 45°C over 15 minutes, and stirring was continued for 8 hours. After the reaction was completed, the reaction mixture was cooled to 15°C, and 1000 ml of 2N hydrochloric acid was added dropwise from the dropwise load to perform acid precipitation, resulting in 2,2-bis(3,5-dihydroxymethyl-4-hydroxyphenyl ) Powdered crystals of propane were precipitated. This was filtered, washed with water, and then dried to obtain 296 tons of powdered crystals. , 2,2-bis(3,5-dihydroxymethyl-
The purity of 4-hydroxyphenyl)propane was 99.5% by weight or more, and the yield was 85% by mole based on the charged 2,2-bis(4-hydroxyphenyl)propane. Note that the purity of the product was measured by liquid chromatography. Examples 2-3, Comparative Examples 1-2 The same reaction apparatus as in Example 1 was used, and the same method as in Example 1 was carried out except that the amount of sodium hydroxide dropped from the dropping load was changed as shown in Table 1. Made it react.

After the reaction was completed, the mixture was post-treated in the same manner as in Example 1. The results are shown in Table 1. Examples 4-5, Comparative Example 3-
5 Using the same reaction apparatus as in Example 1, the reaction was carried out in the same manner as in Example 1, except that the amount of 37% by weight formalin charged into the flask was varied as shown in Table 2.

After the reaction was completed, the mixture was post-treated in the same manner as in Example 1. The results are shown in Table 2. Examples 6 to 7, Comparative Example 6 The reaction was carried out in the same manner as in Example 1 except that the reaction temperature and reaction time were changed as shown in Table 3.

After the reaction was completed, the mixture was post-treated in the same manner as in Example 1. The results are shown in Table 3. Example 8 Using the same reaction apparatus as in Example 1, bis(4-hydroxyphenyl)alkane charged in a flask was converted into bis(4-hydroxyphenyl)alkane.
The reaction was carried out in the same manner as in Example 1 except that hydroxyphenyl)ethane was used.

Claims (1)

[Scope of Claims] 1. Bis(4-hydroxyphenyl)methane, 1,1-bis(4-hydroxyphenyl)ethane and 2,2-bis(4-hydroxyphenyl) in the presence of a basic catalyst in an aqueous solution. ) The corresponding bis(3,5-dihydroxymethyl-4-hydroxyphenyl ) a method for producing alkanes, using an alkali hydroxide as a basic catalyst in an amount of from 1.6 to 2.5 gram atoms as alkali metal atoms per mole of the bis(4-hydroxyphenyl) alkanes; Formaldehyde is used in an amount of 3.7 to 4.3 mol per mol of the bis(4-hydroxyphenyl)alkane, and the reaction is carried out at a temperature in the range of 0 to 55°C, and then the desired product is obtained. Bis(3,5-dihydroxymethyl-
A method for producing 4-hydroxyphenyl) alkanes. 2. Claim 1, wherein the alkali metal hydroxide is used in an amount of 1.7 to 2.1 gram atoms as alkali metal atoms per mole of the bis(4-hydroxyphenyl)alkanes (a). the method of. 3 The usage ratio of formaldehyde (b) is the bis(4-
The method according to claim 1 or 2, wherein the amount is in the range of 3.8 to 4.2 mol per 1 mol of hydroxyphenyl)alkane (a). 4. A method according to any one of claims 1 to 3, wherein the reaction is carried out at a temperature in the range of 30 to 50°C.