JPH02212447A - Production of 4,4'-dihydroxytetraphenylmethanes having improved color tone - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION "Field of Industrial Application" The present invention is applicable to optical 41 m! The present invention relates to a method for producing 4,4'-dihydroxytetraphenylmethanes which are useful as raw material monomers for polycarbonate and the like.

``Prior art'' Conventionally, as a method for producing 4,4'-dihydroxytetraphenylmethanes, there has been a method in which α,α-dichlorodiphenylmethanes and phenols are reacted in the presence of charcoal (arsenic solvent) such as xylene. British Patent No. 1204459 (
(1970).

However, when 4,4'-dihydroxytetraphenylmethane is used as a monomer for polycarbonate, which has an optical function as a component,
Although high quality products are required in terms of color tone, the 4,4'-dihydroxytetraphenylmethanes obtained by the above method are yellow in color and have difficulty in practical use. Of course, 1m for recrystallization, etc.! Although the color tone is improved by turning the edges, there are problems in that the process becomes extremely complicated and the yield decreases.

"Problems to be Solved by the Invention" The present invention attempts to solve the above-mentioned problems that the prior art had.

As a result of repeated research, we have completed the present invention.

That is, α,α-dichlorodiphenylmethanes represented by the following general formula (1) are subjected to a condensation reaction with phenols represented by (2) at most 1, and 4 represented by at most (3) is produced.
When producing 4'-dihydroxytetraphenylmethanes, one or more types of hypophosphorus VI is added to the reaction step and/or purification step.
! The present invention provides a method for producing 4,4'-dihydroxytetraphenylmethanes having improved properties.

General formula - (1) l "However, R1 and R2 in the formula each represent a hydrogen atom, a halogen atom, an alkyl group, an alkoxy group, a cycloalkyl group, an alkenyl group, an aryl group, an aralkyl group, and even if they are the same, The It substituent represented by R1 and R2 other than a hydrogen atom or a halogen atom may further have a substituent. I and 1) each represent an integer of 1 to 5. (2) However, R3 in the formula represents a hydrogen atom, a halogen atom, a furkyl group, an alkoxy group, a cycloalkyl group, an alkenyl group, an aryl group, or an aralkyl group, and R3 other than a hydrogen atom or a halogen atom is The substituent group may further have a substituent group.X represents an integer of 1 to 4.
3) "However, R1, R2, R3 and m, n, x in the formula represent the same sweetness as above." The α,α-dichlorodiphenylmethanes used in the present invention include α,α-dichlorodiphenylmethane. ,α,
Examples include α-dichlorodiphenylmethane derivatives.

Here, the α,α-dichlorodiphenylmethane derivatives are substituted with a nucleus having at least one or more substantially inert substituent on one or both benzene nuclei of the parent α,α-dichlorodiphenylmethane. means dichlorodiphenylmethane.

When there is a plurality of substituents, each substituent may be the same or different.

Here, the term "substantially inert substituent" means a substituent that does not substantially impede the reaction, such as an alkyl group, an alkoxy group, a cycloalkyl group, an alkenyl group, an aryl group, an aralkyl group, etc. Examples thereof include hydrocarbon groups such as groups, halogen-substituted hydrocarbon groups such as halogen-substituted alkyl groups, halogen-substituted alkoxy groups, and halogen-substituted aryl groups, and halogen atoms.

There is no particular restriction on the position of the substituent, but from the viewpoint of reactivity, it is preferable that the substituent be substituted at a position other than 2-16- or 2-16-, and in particular, the same substituent may be substituted at a position other than 4-14-.
Those substituted with '- are preferred.

In the present invention, the following compounds can be used as specific examples of the above-mentioned α,α-dichlorodiphenylmethanes, but they are not limited to the same extent.

For example, α, α-dichlorodiphenylmethane, 4-methyl-α, α-dichlorodiphenylmethane, 4.4'-dimethyl-α, α-dichlorodiphenylmethane, 3.4.
4'-)limethyl-○, α-dichlorodiphenylmethane, 3.4.3'4'-tetramethyl-α, α-dichlorodiphenylmethane, 4-phenyl-α, α-dichlorodiphenylmethane, 4.4'-diphenyl-α , α-dichlorodiphenylmethane, 4-cyclohexyl-α, α
-dichlorodiphenylmethane, 4.4' dicyclohexyl-α, α-dichlorodiphenylmethane, 4-fluoro-α, α-dichlorodiphenylmethane, 4.4'-difluoro-α, α-dichlorodiphenylmethane, 4-chloro-α, Examples include α-dichlorodiphenylmethane, 4,4′-dichloro-〇, α-dichlorodiphenylmethane, and the like.

Among these, α, α-dichlorodiphenylmethane, 4
．． Preferred are 4'-dimethyl-α, α-dichlorodiphenylmethane, 4,4'-dichloro-α, α-dichlorodiphenylmethane, and the like.

Phenols represented by general formula (2) that can be used in the present invention include phenol and phenol derivatives.

Here, the term phenol derivative refers to at least one hydrogen atom among the four hydrogen atoms at the 2-3-166-position that are directly linked to the benzene nucleus of phenol.
Refers to a substituted phenol substituted with 1110 or more substantially inert substituents.

When there are several substituents, each substituent may be the same or different, and a substantially inert substituent is one that substantially impedes the reaction. It is possible to mention the above-mentioned inverted carbon arsenide group, a halogen atom, a halogen-substituted hydrocarbon group, etc., where [ is a substituted group.

Moreover, there is no particular restriction on the position of the substituent.

In the concrete cutting of phenols in the present invention, the following metal fittings can be used, but the method is not limited to the same extent.

For example, phenol, 0-cresol, m-cresol, 2.6-dimethylphenol, 2.3-dimethylphenol, 2.5-dimethylphenol, 3.5-dimethylphenol, 2-ethylphenol, 2-butylphenol, 2 -Phenylphenol, 2-chlorophenol, 3-chlorophenol, 2゜5-dichlorophenol, 2.3-dichlorophenol, 3.5-dichlorophenol, 2-fluorophenol, 3-fluorophenol, 2-benzylphenol, etc. can be mentioned.

Among these, phenol, O-cresol, m-cresol, 2.6-dimethylphenol, 2-chlorophenol, 3-chlorophenol, 2.6-dichlorophenol, 2-phenylphenol, 3-phenylphenol and the like are preferred. Particularly suitable are phenol and 2-methylphenol.

The hypophosphorous acids used in the present invention include hypophosphorous acid and metal salts of hypophosphorous acid, such as sodium salts, potassium salts, calcium salts, magnesium salts, zinc salts, aluminum salts, iron salts, cobalt salts, and nickel salts. etc.

Among these, hypophosphorous acid, sodium hypophosphite salt, potassium primary hypophosphite salt, etc. are suitable.

One or more of these hypothic thWIs are combined at reaction pressure ■
and/or can be added to the purification process. The total amount used is 0.001 to 20% by weight, preferably 0.01 to 0! The amount is %.

If the amount used is less than this amount, the desired quality cannot be obtained, and if the amount used is more than this amount, there is no equivalent advantage.

In the present invention, the convenient molar ratio of phenols represented by general formula -(2) to a,α-dichlorodiphenylmethanes is 2. 0-10.0, preferably 2.0-5
．． It is 0.

If the molar ratio is less than this, the reaction rate will decrease, which is undesirable.
Further, even if the molar ratio is greater than this, there is no equivalent advantage.

The reaction temperature in the present invention cannot necessarily be specified depending on the types of raw materials, solvents, etc. used, but is usually 0 to 30°C.
A temperature of 0°C can be used, but preferably 20 to 200°C.
It is.

If the temperature is lower than this temperature, the reaction rate decreases, which is undesirable, and if the temperature is higher than this temperature, side reactions will proceed, which is undesirable.

The reaction pressure in the present invention is usually carried out under normal pressure, but it can also be carried out under increased pressure if necessary.

According to the present invention, the condensation reaction can be carried out in an m:M medium, but it is preferable to use a solvent if necessary.

The solvent used in the present invention is generally not particularly limited as long as it does not interfere with the reaction.

For example, saturated hydrocarbons such as pentane, hexane, heptane, octane, isooctane, cyclohexane, methylcyclohexane, toluene, xylene, aromatic carbon (hydrocarbon inert solvents such as arsenic) are preferred.

Other examples include non-hydrocarbon solvents such as halogen-substituted alkanes, halogen-II-substituted aromatic carbons, arsenic compounds, ethers, and esters.

Further, these r1i media may be used alone or in combination of two or more if necessary.

Examples of solvents used in the purification process of the present invention include low-strength alcohols, hydrocarbons, halogenated carbons (arsenic, ethers, ketones, and esters 1).

These solvents may be used alone or in combination of two or more if necessary. Preferred solvents include lower alcohols.

"Effects of the Invention" According to the method of the present invention, the extremely dull color tone of 4,4'
-It has the disappointing effect of being able to industrially and efficiently produce dihydroxytetraphenylmethanes.

"Example" Hereinafter, the present invention will be explained in more detail by showing examples, but the i! Of course, the range is not limited to the same extent as m described in the examples.

Example-1 1.88g (2.0mol) of phenol was charged into a 10,100O capacity four-hole flask equipped with a stirrer, a thermometer, a dropping funnel, and a cooling condenser whose tip was led into a water trap, and the internal temperature was lowered. After raising the temperature to 50°C to dissolve the phenol, while keeping the internal temperature at 50°C, add 123g of α,α-dichloro-a-diphenylmethane (purity 96.3%,
0.5 mol) was added dropwise over 1 hour. After that, 500 n11 of xylene was added to the reaction product and the internal temperature was raised to 100℃.
The temperature was then raised, and stirring was continued for 4 hours while maintaining the same temperature to complete the reaction. Hydrogen chloride produced as a by-product during the reaction was absorbed into water.

The reaction product obtained here was treated in a conventional manner to obtain 153 gr of a crude product.

Add 50% aqueous hypophosphorous acid lαI to this crude product.

5grg: After addition, recrystallize with methanol to obtain 128g of white 4,4'-dihydroxytetraphenylmethane.
I got r. This corresponds to a yield of 72.7% based on the α,α-dichloro-O diphenylmethane L used. The purity of this product by liquid chromatography is 99.8%, A
PHA (Note-1) was 30.

Example 2 50 gr of crude product J was prepared in the same manner as in Example 1, except that 1.5 gr of a 50% aqueous hypophosphorous acid solution was added during the reaction. This was further recrystallized with methanol to give a white 4.
125 gr of 4'-dihydroxytetraphenylmethane was obtained. This corresponds to a yield of 71.0% based on the α,α-dichlorodiphenylmethane used. The purity of this product was 99.7%, and the APHA was 30.

Example-3 1.15g of 50% hypophosphorous acid solution was mixed with 0.1g of sodium hypophosphite monohydrate. 7δg r 1. The procedure was carried out in the same manner as in Example 1, except that 4.4' dihydroxytetraphenylmethane 12 (3 gr.
, corresponding to a yield of 71.6% based on α-dichlorodiphenylmethane. The purity of this product is 99.7%, and the APH
There were 40 A's.

Example 4 The same procedure as in Example 1 was carried out except that 103 gr (1.1 mol) of phenol was used to obtain 115 gr of 4,4'-dihydroxytetraphenylmethane. This is the α used
, corresponding to a yield of 65.3% based on α-dichlorodiphenylmethane. The purity of this product is 99.5%, APHA
It was 50 and 7.

Example 6 The same procedure as in Example 1 was carried out except that the post-stirring temperature was changed to 150°C to obtain 132 gr of white 4,4'-dihydroxytetraphenylmethane. This corresponds to a yield of 75.0% based on the α,α-dichlorodiphenylmethane used. The purity of this product was 99.8%, and the AP HA was 30.

Implementation η1j-6 Example-1 except that xylene in Example-1 was replaced with toluene.
The same procedure as in 1 was carried out to obtain 113 gr of 4,4'-dihydroxytetraphenylmethane. This corresponds to a yield of 64.2% based on the α,α-dichlorodiphenylmethane used. The purity of this product was 99.6%, and the APHA was 40.

Example-7 0-cresol 21 instead of phenol in Example-1
The same procedure as in Example 1 was carried out except that 6 gr (2.0 mol) was used, and 133 gr of bis(4-hydroxy-3-methylphenyl)-diphenylmethane was obtained. This is 7 for the α,α-dichlorodiphenylmethane used.
This corresponds to a yield of 0.0%. The purity of this product is 99.7
%, APHA was 40.

Real right tfWori-8 Instead of α,α-dichlorodiphenylmethane in Example-1, 4.4'-dimethyl-〇,α-dichlorodiphenylmethane 138g (purity 96.0%, 0.5 mol)
The procedure was carried out in the same manner as in Example-1 except that screws (4
-hydroxyphenyl)-bis(4-methylphenyl)
- 137 gr of methane were obtained.

This corresponds to a yield of 72°1% based on the 4,4'-dimethyl-α,α-dichlorodiphenylmethane used.
The purity of this product was 99.8% and the APHA was 30.

Comparative Example 128 grG of 4,4'-dihydroxytetraphenylmethane was obtained in the same manner as in Example 1, except that 50% aqueous hypophosphorous acid solution was not added. This corresponds to a yield of 72.7% based on the α,α-dichlorodiphenylmethane used. The purity of this product is 99.8%, and the APHA is 100%.
Met.

(Note 1) APHA + direct is J15K-6727 (1963,
Sample 5.
After collecting Ogr in a Nessler tube, add methanol/acetone (1/1) to the standard line to dissolve the sample. Standard iff (Note 2), which is placed in a Nessler tube prepared separately.
The APHA value was determined by comparing with

(Main 2) The standard source was prepared as follows.

Approximately 1 potassium platinum chloride to contain 0.500g of platinum
．． JIS to include 25gr and 0.25gr of cobalt
Approximately 1 gram of cobalt chloride from ``K-8t29r Cobalt Chloride (Special Reagent Grade)'' was dissolved in 100ml of hydrochloric acid from ``K-818Or Hydrochloric Acid (Special Reagent Grade)'', and then dissolved for 10 minutes with distilled water.
When diluted to 100O, it becomes a stock solution of APHA=500.

For example, take 40ml of this and add distilled water to 10100O
If diluted to , it corresponds to A P HA = 20.

"Trial Example" 20g of each of the samples obtained in the above Examples and Comparative Examples were placed in a polyethylene bag and sealed with vE. This was exposed to intermittent sunlight for a certain period of time, and the color change over time of each sample was measured by AP R, 1! compared with.

The results are shown in the table below.

"Discoloration over time 2 APlrA due to sunlight exposure" (Table) Sample Start of test amount 30 days later Example-13030 Example-2 Example-3 Comparative example As shown in the above test example, the product obtained by the method of the present invention changes in color over time. It is clear that the performance has also been significantly improved.

Claims (7)

[Claims] (1) α,α-dichlorodiphenylmethanes represented by the general formula (1) and phenols represented by the general formula (2) are subjected to a condensation reaction, and the 4, α-dichlorodiphenylmethanes represented by the general formula (3) are
4, 4 with improved color tone characterized by adding one or more selected from hypophosphorous acids to the reaction step and/or purification step when producing '-dihydroxytetraphenylmethanes. A method for producing '-dihydroxytetraphenylmethanes. General formula - (1) ▲ Numerical formulas, chemical formulas, tables, etc. ▼ "However, R_1 and R_2 in the formula are hydrogen atoms, halogen atoms, alkyl groups, alkoxy groups, cycloalkyl groups, alkenyl groups, aryl groups, aralkyl groups, respectively. Indicates a group, each of which may be the same or different, and a hydrogen atom,
The substituents represented by R_1 and R_2 other than the halogen atom may also have a substituent, m and n are each 1 to 5.
represents an integer. ” General Formula - (2) ▲ Numerical formulas, chemical formulas, tables, etc. The substituent represented by R_3 other than a hydrogen atom or a halogen atom may further have a substituent, and x represents an integer from 1 to 4.'' General formula - (3) ▲ Numerical formula, chemical formula, table, etc. Yes▼ ``However, R_1, R_2, R_3 and m, n, x in the formula
has the same meaning as above. ” (2) The production method according to claim (1), wherein the hypophosphorous acid is hypophosphorous acid and/or a metal salt of hypophosphorous acid. (3) The total amount of hypophosphorous acids added to the reaction step and/or purification step is α, α- as shown by the general formula (1).
0.001-20 for dichlorodiphenylmethanes
% by weight. (4) A claim in which the molar ratio of the phenol represented by the general formula (2) to the α,α-dichlorodiphenylmethane represented by the general formula (1) is in the range of 2.0 to 10.0. The manufacturing method described in item (1). (5) The production method according to claim (1), wherein the condensation reaction temperature is in the range of 0 to 300°C. (6) The production method according to claim (1), wherein the condensation reaction solvent is a hydrocarbon. (7) The production method according to claim (1), wherein the purification solvent is one or a mixed solvent of two or more selected from alcohols, hydrocarbons, halogenated hydrocarbons, ethers, ketones, and esters.