CN1163257A - Process for preparing and purifying 1,1,1-tri(4-hydroxyphenol) ethane - Google Patents
Process for preparing and purifying 1,1,1-tri(4-hydroxyphenol) ethane Download PDFInfo
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- CN1163257A CN1163257A CN 97102113 CN97102113A CN1163257A CN 1163257 A CN1163257 A CN 1163257A CN 97102113 CN97102113 CN 97102113 CN 97102113 A CN97102113 A CN 97102113A CN 1163257 A CN1163257 A CN 1163257A
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- ethane
- hydroxyphenyl
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Abstract
This 1,1,1-tris(4-hydroxphenyl)ethane is obtained as its mixture with bisphenol A by reacting 2,4-pentanedione with excessive phenol in the presence of a mercapto compound as a reaction accelerator under an acidic condition. The product can be separated by extracting bisphenol A with a chlorinated alkane. The purification of the obtained 1,1,1-tris(4-hydroxyphenyl) ethane can be achieved by slurrying the compound in methanol-water optionally mixed with optionally an alkali metal borohydride or a dithionite and/or recrystallizing the compound.
Description
The application is the part continuation application of common pending application series number [RD-24972] and the right of priority that requires convention application 08/583,264.
The present invention relates to the agent of polycarbonate side chain, more particularly 1,1, the preparation and the purification of 1-three (4-hydroxyphenyl) ethane (hereinafter to be referred as " THPE ").
THPE is disclosed in US3, and 579,542 and 4,992,598, generally be used as the side chain agent of polycarbonate.Therefore, it can be merged in the reaction mixture that contains dihydroxy aromatic compounds such as dihydroxyphenyl propane and carbonate source such as phosgene or diphenyl carbonate.
By the prepared in reaction of 4-hydroxy acetophenone and phenol, this response class is similar to phenol and acetone generates 2 usually for THPE, the reaction of two (4-hydroxyphenyl) propane (to call " dihydroxyphenyl propane " in the following text) of 2-.As at US4, shown in 992,598, this product can be through methanol-water mixtures washing and/or recrystallization and is purified, and preferably adds the sodium borohydride of decolouring amount.This method is nonconforming economically, because 4-hydroxy acetophenone price is very high.Therefore, people wish to find-method of the production THPE that kind of expense is low.
According to the day disclosure 53/141,250, diketone is as 2,4-diacetylmethane and excessive phenol are under acidic conditions and as providing 2,2,4, there is reaction down in the sulfhydryl compound of the promotor of 4-four (4-hydroxyphenyl) pentane, and all aspects of this reaction all are similar to the preparation of above-mentioned dihydroxyphenyl propane.
Have found that, 2 described in the above-mentioned day disclosure, the reaction between 4-diacetylmethane and phenol at least under suitable condition, does not produce described four phenol but produces THPE and dihydroxyphenyl propane.So these compounds can be recovered in order further using and to separate, and obtain the THPE of high yield.
Therefore, a first aspect of the present invention is the method for preparing THPE, and it comprises:
Exist down as promotor in the sulfhydryl compound of acidic conditions and significant quantity, heat phenol and 2 in about 30-100 ℃, 4-diacetylmethane mixture obtains the mixture of dihydroxyphenyl propane and THPE, phenol and 2 wherein, and the mol ratio of 4-diacetylmethane was at least about 6: 1; With
From this dihydroxyphenyl propane, separate this THPE.
Second aspect of the present invention is preparation and the method for purification THPE, and it comprises above-mentioned heating steps and in addition:
Merge dihydroxyphenyl propane-THPE mixture and a certain amount of alkyl chloride,, and separate this precipitation with the THPE-dihydroxyphenyl propane mixture precipitation of generation enrichment THPE;
This precipitation is contacted with the methanol-water mixtures that contains 40% (volume) methyl alcohol at least, and this methanol-water mixtures is saturated with THPE in advance, obtain a kind of THPE soup compound and
From this soup compound, reclaim pure THPE.
In the first aspect of method of the present invention, phenol and 2, the 4-diacetylmethane uses with the mol ratio at least about 6: 1.Higher mol ratio typically was at least about 8: 1, provided extra high productive rate and about 11: 1 above mol ratios more useful, because at room temperature reaction mixture keeps liquid to help the operation and the purification of product at least in part.When mol ratio is low, about 40 ℃ the reaction mixture of liquid, reaction mixture cured near 25 ℃ the time.
Phenol and 2 under acidic conditions, the 4-diacetylmethane is with at least about 6: 1 mixed in molar ratio.Mixing can be any order.For in to keep phenol in free be big excessive, incrementally add (for example dropping) 2 gradually, the 4-diacetylmethane is useful in phenol.Can solvent-applied, but not necessarily.
Acidic conditions can provide by material such as the hydrogenchloride that adds any acidic substance, particularly relative volatility.Typical way is that during reaction logical hydrogen chloride gas passes through mixture.Add aqueous acids also within the scope of the present invention, or replace the gas acidic substance or except the gas acidic substance, add aqueous acids again.
Be meant as the sulfhydryl compound of promotor to have-organic compound of SH base section, the sulfhydryl compound of preferred relative volatility, the acid of band sulfydryl carboxyl such as 3-thiohydracrylic acid and 2-Thiovanic acid are useful especially.Significant quantity as this sulfhydryl compound of promotor is generally about 1-5% (weight) based on phenol.
Typical temperature of reaction is about 30-100 ℃, preferably about 30-60 ℃.Between the reaction period, THPE and dihydroxyphenyl propane with 1: 1 weight ratio with solids constituent from, therefore, it is very sticking that mixture may become.
In last preparation process, THPE and dihydroxyphenyl propane are separated.Conventional separation method is that the 2-ethylene dichloride extracts and removes dihydroxyphenyl propane with alkyl chloride such as methylene dichloride or 1.Most this dihydroxyphenyl propane can reclaim by the evaporation of alkyl chloride.In extracting residue, the weight ratio of THPE and dihydroxyphenyl propane 94: 6 typically.If require from dihydroxyphenyl propane, thoroughly to tell THPE, should handle twice with alkyl chloride at least.The unreacted phenol of small proportion the most often reaches heavy about 1% of total crude product, generally also is present in the residue.
When 2, when 5-hexanedione and phenol reacted under above-mentioned condition in broadly similar, from the disclosure 53/141,250 expection in above-mentioned day, product was 2,2,5,5-four (4-hydroxyphenyl) hexane.Therefore, THPE and dihydroxyphenyl propane are 2, and this fact of products therefrom is not suspected fully under the 4-diacetylmethane condition.
A second aspect of the present invention comprises a few step purified product THPE.First purification step, above-mentioned 2, the reaction one between 4-diacetylmethane and phenol is finished promptly and is carried out, and is generally the crude product of the mixture of THPE and dihydroxyphenyl propane and small proportion unreacting phenol, with above-mentioned alkyl chloride normally methylene dichloride combine.The methylene dichloride of q.s generally is that the volume ratio to crude product was at least about 2.5: 1 and is generally about 3: 1.Before or after adding methylene chloride, crude product can be by neutralizing with alkaline reagents such as sodium hydroxide or sodium bicarbonate.
Alkyl chloride can be separated in conjunction with promptly precipitating also with the mixture of dihydroxyphenyl propane (to call the enrichment mixture in the following text) with the THPE of enrichment THPE.This enrichment mixture contains the nearly THPE of 98% (weight), its surplus be main be dihydroxyphenyl propane.
Crude product is converted into the actual reduction that the enrichment mixture is accompanied by color.Usually, the APHA chromatic number of crude product is about 2000 or bigger, and the chromatic number of this enrichment mixture is about 1000.Yet, for as the side chain agent of polycarbonate, toner be 150 or littler basic colourless product be necessary.Can not further purify and decolour with the alkyl chloride repetitive scrubbing, require other purification step.
In the first other purification step, this enrichment mixture contacts with the methanol-water mixtures that contains 40% methyl alcohol (volume) at least.Find, when the volume of methyl alcohol in the methanol-water mixtures less than 40% the time, a large amount of dihydroxyphenyl propanes is typically greater than 2% (weight) and stays in the product.Usually, the ratio of methyl alcohol is about 42-50% (volume) in methanol-water mixtures.In order to suppress the dissolving of THPE in methanol-water mixtures, this mixture is saturated with THPE before using.So saturated methanol-water mixtures is called " washings " hereinafter.
Contacting between this washings and this enrichment mixture can be by pulpous stateization or only by washing.Typical contact temperature is in about 25-50 ℃ scope.This washings can contain alkali metal borohydride or the hyposulfite of the about 0.01-0.10% of being generally of decolouring ratio (weight) in addition, preferred sodium borohydride (NaBH
4) or V-Brite B (Na
2S
2O
3), sodium borohydride preferably.
When by the pulpous state contact, reclaim pure THPE by filtering from gained THPE slurry, if when producing soup compound, used higher temperature, be chilled to about 25 ℃ usually in advance.The purity of the THPE that gained is pure in this step generally is at least 98%, is that main impurity is dihydroxyphenyl propane.
Methyl alcohol one filter liquor that reclaims from the THPE that purifies is that THPE is saturated.Therefore, it is capable of circulation as washings.
The pure THPE that is obtained by aforesaid method generally is flaxen.It is dissolved in alkali metal borohydride or the hyposulfite of also using the decolouring ratio in the methyl alcohol handles, can be converted into pure basically white product.One is treated, and initial amber solution is transformed into faint yellow.Under 25-50 ℃, filter and remain in this temperature range, then, under agitation slowly add the water of same temperature, if desired, again solution is chilled to envrionment temperature, obtain pure basically white solid precipitation.
When contacting between washings and enrichment mixture is to want rather than during pulpous state, with this washings hydro-peening filter cake, gained enrichment mixture has high slightly content of bisphenol A, often reaches 5% (weight) by washing.As above-mentioned, it can further contact with the methyl alcohol that contains decolouring ratio alkali metal borohydride or hyposulfite, and at random can contact with decoloration active carbon.After the filtration, if desired, gained solution can combine with water with the precipitation final product, and it generally contains the THPE at least about 97%, and its surplus is a dihydroxyphenyl propane.When this product will be used as the agent of polycarbonate side chain, the ratio of dihydroxyphenyl propane can change.
The present invention further illustrates with following embodiment.Unless otherwise specified, all per-cents are meant weight.
Embodiment 1
In the 500ml round-bottomed flask that is equipped with stirring, 100g (1.06mole) phenol is housed, mark in 1.50g (14mmole) 3-thiohydracrylic acid and 100mg p-terphenyl are done.Reaction mixture is warmed to 60 ℃, the phenol melting.In reaction mixture, blast hydrogenchloride 30 minutes, and then, be chilled to 40 ℃ and in 30 minutes, drip power 8.8g (83.3mmol) 2,4-diacetylmethane.Continue heating down in 40 ℃ and also feed hydrogen chloride gas every now and then, during this, reaction mixture becomes very sticking and slowly forms precipitation.Under room temperature, continue to stir 24 hours.
The filtration fraction reaction mixture obtains orange solids, and it is the mixture of THPE and dihydroxyphenyl propane for an analysis revealed.Power 300ml methylene dichloride is settled out faint yellow solid in the remaining mixture, filters.Liquid-phase chromatographic analysis shows that this solid is about 95: 5 THPE and the mixture of dihydroxyphenyl propane.Extract with methylene dichloride again, obtain a kind of light orange solid, it is the THPE that only contains about 1-2% dihydroxyphenyl propane for an analysis revealed.The total thick productive rate of THPE is about 49.5% of a theoretical value.
Evaporate methylene dichloride, obtain the dihydroxyphenyl propane of about 50-60% productive rate.
Embodiment 2-7
Repeat the process of embodiment 1, change comprises phenol and 2, the mol ratio of 4-diacetylmethane, and the ratio of promotor, parameters such as temperature and reaction times obtain the listed result of Table I.
Table I embodiment phenol and 2,4-penta promotor thermotonus time T HPE
The mol ratio mole % of diketone
*℃
*Hour productive rate (%)
2 6∶1 3 60-RT 24 48
3 8∶1 1.5 40 40 49
4 8∶1 1.5 60-RT 64 59
5 9∶1 1.5 60-RT 30 52
6 10∶1 1.5 60-RT 48 59
7 12∶1 3.0 60-RT 72 61
*The RT=room temperature
*In phenol
Embodiment 8
Be equipped with 94g (1mole) phenol is housed in the churned mechanically 250ml round-bottomed flask, 3.06g (28.9mmol) 3-thiohydracrylic acid, the hydrochloride aqueous solution of 1.65ml 38% and 100mg p-terphenyl are as interior mark.Heated mixt to 60 then, blasted hydrogenchloride 30 minutes ℃ with melting phenol in mixture.Make mixture be chilled to room temperature and in 30 minutes, add 8.33g (83mmol) 2,4-diacetylmethane.Continued logical hydrogenchloride 8 hours under room temperature, during this, it is very sticking that mixture becomes.Continue to stir 40 hours.
One stops to stir, and reaction mixture promptly is cured as red-brown.Add the 150ml methylene dichloride, obtain faint yellow precipitation, filter.Liquid-phase chromatographic analysis shows that it is about 95: 5 THPE and the mixture of dihydroxyphenyl propane.Extract filtrate again with methylene dichloride, obtain second batch of product, it is 90: 1 the THPE and the mixture of dihydroxyphenyl propane.The total thick productive rate of THPE is 59.9%.
One concentrated filtrate also adds water and promptly forms the light red solid, and analysis revealed wherein has 55% phenol, is less than 5% THPE and 40% and is dihydroxyphenyl propane.The overall yield of dihydroxyphenyl propane is about 50%.
Embodiment 9
Prepare phenol and 2 to be similar to the described reaction process of embodiment 1 first part, the reaction product of 4-diacetylmethane, pulping and filtration in methylene dichloride.Filter residue is the light yellow orange solid, and it has 2144 APHA chromatic number.Liquid-phase chromatographic analysis finds that it contains 93.4%THPE, 5.8% dihydroxyphenyl propane and 0.6% phenol.This crude product of 100g was containing in the water-methanol mixture of 58% (weight) water and 42% methyl alcohol (weight) pulping 20 minutes at 300ml under 50 ℃, and this mixture is saturated with THPE in advance.Stirring down made soup compound be chilled to room temperature in 2 hours.Solid collected by filtration is also analyzed, and finds that it has 1021 APHA chromatic number and contains 98.3%THPE and 1.7% dihydroxyphenyl propane.
Embodiment 10
The product of the embodiment 9 of different parts (every part of 30g) is dissolved in the methyl alcohol, and the gained amber solution is handled with the 50ml sodium borohydride, its as a result solution become very faint yellow.Filtering solution also under agitation adds different parts water under 50 ℃ or room temperature.The solution of gained muddiness at room temperature stirred 2 hours, filtered, and contained the water-methanol solution washing of 70% (volume) water and 30% methyl alcohol with 100ml.Then, desciccate under 40 ℃ of vacuum.
The result as shown in Table II.Productive rate calculates with initial 30g sample.
Table II experiment numbers methanol-water temperature productive rate THPE APHA
Ml ml ℃ of % purity % chromatic number
1 50 60 25 82 99.2 149
2 50 70 25 70 99.1 118
3 45 60 25 77 99.1 123
4 60 60 25 86 99.3 94
5 60 60 50 85 99.7 78
6 60 70 50 89 99.3 86
7 60 80 50 91 99.1 80
8 60 90 50 92 99.0 85
From Table II as can be seen, precipitate than sedimentary THPE productive rate is higher and its color is more shallow at 25 ℃ in 50 ℃.Degree of purity of production is identical substantially, and is irrelevant with precipitation temperature.In each embodiment, the impurity of examining and determine out only is dihydroxyphenyl propane.
Embodiment 11
Repeat the process of embodiment 9, change the volume ratio of water-methanol.Its result as shown in Table III.
Table III
Analyze experiment numbers water-methanol volume ratio THPE BPA phenol APHA chromatic number
1 50∶50 98.3 1.7 -- 1021
2 58∶42 99.4 0.6 -- 1408
3 60∶40 98.2 1.8 -- 1204
4 70∶30 97.2 2.6 0.22 1171
5 80∶20 94.6 4.9 0.5 1392
From Table III as can be seen, when methanol-water mixtures contains at least 40% (volume) methyl alcohol, obtain obviously high product of purity.Chromatic number does not show the effect that comes down to the water-methanol ratio.
Embodiment 12
Add 19 parts of (200mmol) phenol in the glass-lined reactor and in the following 50 ℃ of heating of nitrogen atmosphere.Add 0.285 part of thiohydracrylic acid and 0.019 part of p-terphenyl as interior mark.Solution is saturated with gaseous hydrogen chloride, adds 2 parts of (20mmol) 2, the 4-diacetylmethane.In 40 ℃ of heating this solution 48 hours, after reaction was finished, liquid-phase chromatographic analysis showed that THPE is 61%.
Add methylene chloride in mixture, the gained soup compound is stirred 2 hours to precipitate thick THPE.Filter soup compound, with other washed with dichloromethane, drying gets 3.43 parts of light brown solids, and it contains 94%THPE (53% thick productive rate), 5.4% dihydroxyphenyl propane and 0.6% phenol.
With 13.9 parts of water-methanol solution washing filter cakes, this solution contains 58% (volume) water and 42% (volume) methyl alcohol and saturated and contain 0.05% sodium borohydride with THPE in advance.Product analysis after the washing shows that it contains 94.1%THPE and 4.9% dihydroxyphenyl propane.
The filter cake of washing is dissolved in 6.9 parts of methyl alcohol and adds 0.001 part of sodium borohydride, and color shoals significantly.Then, add 0.0015 part of decolorizing charcoal.Stir this solution 30 minutes, and filtered, obtain yellow solution.Be heated to 40 ℃ and in this temperature with stir and to add 10 parts of deionized waters that contain 0.001 part of sodium borohydride down.Be chilled to room temperature in 2 hours, be settled out pure THPE, filter, drying is analyzed and is found that it contains 97.5%THPE and 2.5% dihydroxyphenyl propane.
Claims (10)
1. one kind prepares 1,1, the method for 1-three (4-hydroxyphenyl) ethane, and this method comprises:
Under acidic conditions and in the presence of the sulfhydryl compound as promotor of significant quantity, in about 30-100 ℃ of scope internal heating phenol and 2, the mixture of 4-diacetylmethane, phenol and 2, the mol ratio of 4-diacetylmethane is at least about 6: 1, obtains dihydroxyphenyl propane and 1,1, the mixture of 1-three (4-hydroxyphenyl) ethane and
Separate institute from dihydroxyphenyl propane and want 1,1,1-three (4-hydroxyphenyl) ethane.
2. the process of claim 1 wherein phenol and 2, the mol ratio of 4-diacetylmethane was at least 8: 1.
3. the process of claim 1 wherein that acidic conditions provides by adding chlorination hydrogen.
4. the process of claim 1 wherein that the amount of sulfhydryl compound is about 1-5% (weight) based on phenol.
5. the process of claim 1 wherein that separating step is to extract once at least with alkyl chloride to finish to remove dihydroxyphenyl propane.
6. the method for claim 5 is wherein extracted and is carried out twice at least.
7. one kind prepares and purifies 1,1, the method for 1-three (4-hydroxyphenyl) ethane, and this method comprises:
Under acidic conditions and in the presence of the sulfhydryl compound as promotor of significant quantity, in about 30-100 ℃ of scope heating phenol and 2, the mixture of 4-diacetylmethane, phenol and 2, the mol ratio of 4-diacetylmethane were at least about 6: 1, obtained dihydroxyphenyl propane and 1,1,1-three (4-hydroxyphenyl) ethane;
Make a kind of enrichment 1,1 of generation in conjunction with this mixture and a certain amount of alkyl chloride, 1,1 of 1-three (4-hydroxyphenyl) ethane, the mixture precipitation of 1-three (4-hydroxyphenyl) ethane and dihydroxyphenyl propane, and separate this precipitation;
This precipitation is contacted with the methanol-water mixtures that contains 40% (volume) methyl alcohol at least, and this methanol-water mixtures is earlier with 1,1,1-three (4-hydroxyphenyl) ethane is saturated, obtain a kind of 1,1,1-three (4-hydroxyphenyl) ethane soup compound; With
From this soup compound, reclaim pure 1,1,1-three (4-hydroxyphenyl) ethane.
8. the method for claim 7, wherein this methanol-water mixtures also contains the alkali metal borohydride or the hyposulfite of decolouring ratio.
9. the method for claim 7, wherein from pure 1,1, the methanol-water mixtures recirculation of telling in 1-three (4-hydroxyphenyl) ethane is used to contact other precipitation.
10. the method for claim 7, wherein this is pure 1,1,1-three (4-hydroxyphenyl) ethane contacts with other methyl alcohol and forms solution, and this solution is combined with water, therefrom redeposition go out other pure 1,1,1-three (4-hydroxyphenyl) ethane.
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| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN 97102113 CN1163257A (en) | 1996-01-05 | 1997-01-04 | Process for preparing and purifying 1,1,1-tri(4-hydroxyphenol) ethane |
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| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| US583264 | 1996-01-05 | ||
| CN 97102113 CN1163257A (en) | 1996-01-05 | 1997-01-04 | Process for preparing and purifying 1,1,1-tri(4-hydroxyphenol) ethane |
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Cited By (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN101111463B (en) * | 2005-01-31 | 2011-04-06 | 沙伯基础创新塑料知识产权有限公司 | Methods for preparing 1,1,1-tris(4-hydroxyphenyl)alkanes |
| CN102241568A (en) * | 2010-04-07 | 2011-11-16 | 拜尔材料科学股份公司 | Purification of tris-hydroxyaryl compounds |
| CN102942454A (en) * | 2012-11-29 | 2013-02-27 | 太仓市茜泾化工有限公司 | Preparation method of 1,1,1-tri(4-hydroxyphenyl)ethane |
| CN114573425A (en) * | 2022-03-16 | 2022-06-03 | 安徽觅拓材料科技有限公司 | Purification method and application of 1, 1, 1-tri (4-hydroxyphenyl) compound |
-
1997
- 1997-01-04 CN CN 97102113 patent/CN1163257A/en active Pending
Cited By (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN101111463B (en) * | 2005-01-31 | 2011-04-06 | 沙伯基础创新塑料知识产权有限公司 | Methods for preparing 1,1,1-tris(4-hydroxyphenyl)alkanes |
| CN102241568A (en) * | 2010-04-07 | 2011-11-16 | 拜尔材料科学股份公司 | Purification of tris-hydroxyaryl compounds |
| CN102241568B (en) * | 2010-04-07 | 2016-01-20 | 拜尔材料科学股份公司 | Purification of tris-hydroxyaryl compounds |
| CN102942454A (en) * | 2012-11-29 | 2013-02-27 | 太仓市茜泾化工有限公司 | Preparation method of 1,1,1-tri(4-hydroxyphenyl)ethane |
| CN114573425A (en) * | 2022-03-16 | 2022-06-03 | 安徽觅拓材料科技有限公司 | Purification method and application of 1, 1, 1-tri (4-hydroxyphenyl) compound |
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