CN106966901B - A kind of preparation method of 6- hydroxyl -8- Lipase Catalyzed Resolution of Racemic Ethyl - Google Patents
A kind of preparation method of 6- hydroxyl -8- Lipase Catalyzed Resolution of Racemic Ethyl Download PDFInfo
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- CN106966901B CN106966901B CN201610018183.9A CN201610018183A CN106966901B CN 106966901 B CN106966901 B CN 106966901B CN 201610018183 A CN201610018183 A CN 201610018183A CN 106966901 B CN106966901 B CN 106966901B
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- kodalk
- water layer
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- C—CHEMISTRY; METALLURGY
- C07—ORGANIC CHEMISTRY
- C07C—ACYCLIC OR CARBOCYCLIC COMPOUNDS
- C07C67/00—Preparation of carboxylic acid esters
- C07C67/30—Preparation of carboxylic acid esters by modifying the acid moiety of the ester, such modification not being an introduction of an ester group
- C07C67/31—Preparation of carboxylic acid esters by modifying the acid moiety of the ester, such modification not being an introduction of an ester group by introduction of functional groups containing oxygen only in singly bound form
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- C—CHEMISTRY; METALLURGY
- C02—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
- C02F—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
- C02F9/00—Multistage treatment of water, waste water or sewage
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- C—CHEMISTRY; METALLURGY
- C02—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
- C02F—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
- C02F1/00—Treatment of water, waste water, or sewage
- C02F1/001—Processes for the treatment of water whereby the filtration technique is of importance
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- C—CHEMISTRY; METALLURGY
- C02—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
- C02F—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
- C02F1/00—Treatment of water, waste water, or sewage
- C02F1/02—Treatment of water, waste water, or sewage by heating
- C02F1/04—Treatment of water, waste water, or sewage by heating by distillation or evaporation
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- C—CHEMISTRY; METALLURGY
- C02—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
- C02F—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
- C02F2301/00—General aspects of water treatment
- C02F2301/08—Multistage treatments, e.g. repetition of the same process step under different conditions
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Abstract
The invention discloses a kind of lipoic acid intermediates, that is the preparation method of structural formula 6- hydroxyl -8- Lipase Catalyzed Resolution of Racemic Ethyl as shown in formula (I), 6- hydroxyl -8- the Lipase Catalyzed Resolution of Racemic Ethyl is that the 6- oxo -8- Lipase Catalyzed Resolution of Racemic Ethyl as shown in formula (II) is made as starting material by restoring using structure.The present invention is compared with prior art, its advantage is mainly that synthesis step is succinct, reduce the use of organic solvent, avoid direct discharging of waste water, so that the kodalk generated is easily isolated, kodalk solid will not be successfully recycled, in addition also ammonium hydroxide has been recycled with other substance reactions.Particularly, it by recycling kodalk, for industrially further recycling prepares sodium borohydride by boron element, recycles boron element acquisition and creates possibility.Entire technique meets green syt and technology requirement, is suitable for large-scale industrial production.
Description
Technical field
The invention belongs to organic synthetic route design and industrial waste water treatment, in particular to a kind of 6- hydroxyl -8
The preparation method and waste water containing boron processing method of Lipase Catalyzed Resolution of Racemic Ethyl.
Background technique
6- hydroxyl -8- Lipase Catalyzed Resolution of Racemic Ethyl is one of the intermediate that lipoic acid is prepared using adipic acid as starting material, wherein with
6- oxo -8- Lipase Catalyzed Resolution of Racemic Ethyl passes through reduction preparation 6- hydroxyl -8- Lipase Catalyzed Resolution of Racemic Ethyl.Lipoic acid has powerful anti-oxidant energy
Power is mainly used for the treatment of diabete peripheral herve pathology at home；In foreign countries in addition to as drug, it is also used as dietary supplements
And cosmetic material is widely used.
6- oxo -8- Lipase Catalyzed Resolution of Racemic Ethyl reduction preparation 6- hydroxyl -8- Lipase Catalyzed Resolution of Racemic Ethyl technique, mainly uses 6- oxo -8-
Lipase Catalyzed Resolution of Racemic Ethyl obtains 6- hydroxyl -8- Lipase Catalyzed Resolution of Racemic Ethyl, instead by selective reducing agent such as sodium borohydride, the carbonyl of reduction the 6th
Answer equation as follows:
US2792406 reports a kind of side for preparing 6- hydroxyl -8- Lipase Catalyzed Resolution of Racemic Ethyl when description prepares lipoic acid route
Method.6- oxo -8- Lipase Catalyzed Resolution of Racemic Ethyl is dissolved in tetrachloroethanes, be cooled to 10 DEG C hereinafter, be added dropwise ethanol solution of sodium borohydride (1:
20) it, is added dropwise, reacts at room temperature 1.5~2 hours, adjust pH=1~2 with hydrochloric acid, add water stratification, organic layer sodium bicarbonate,
Anhydrous magnesium sulfate is dry, and vacuum concentration obtains 6- hydroxyl -8- Lipase Catalyzed Resolution of Racemic Ethyl.
In above-mentioned patent description, after adding water stratification, organic layer obtains product, and is not described further to water layer processing.
In actual production, it since above-mentioned water layer contains sodium borohydride and ethanol synthesis mixture, can not separate, recycling difficulty is big,
It can only make harmless treatment when waste water.
And the method report for handling waste water containing boron has very much, patent ZL02158593.5 reports a kind of place of waste water containing boron
Reason method is added oxidation/flocculation treatment of oxidant (such as hydrogen peroxide) and flocculant using two sections, boron content is greatly reduced
Afterwards, then ion-exchange-resin process or hyperfiltration is cooperated to remove residual low concentration part, sends out the waste water containing boron of high concentration for example
Power plant effluent can the target processed that reach discharge standard.But not using boron element as resource recycling.
It is well known that by-product is kodalk after preparing hydrogen by sodium borohydride hydrolysis.Industrially, kodalk can pass through carbonization
Method prepares borax；By being acidified neutralisation, it is commonly called as two-step method, preparing boric acid as raw material using borax is to produce boron both at home and abroad at present
The method that acid generallys use；Boric acid is the raw material for industrially preparing sodium borohydride again；Follow boron element through the above steps
Ring utilizes.Easier, " current situation of sodium borohydride synthesis and preparation method " (" power technology " 3 phases in 2008) are reported
By electrochemical techniques, the method for sodium borohydride is directly prepared with kodalk.As long as being generated as it can be seen that sodium borohydride is reacted
By-product kodalk separate, industrially just there is method carry out boron element and recycle.
From green syt and cleanly production angle, it is necessary to seek a kind of new 6- hydroxyl -8- Lipase Catalyzed Resolution of Racemic Ethyl
Preparation method, so that after the completion of reaction, sodium borohydride obtains kodalk and the substance for being dissolved in water layer after participating in reduction reaction
It is readily able to separate, reaches and reduce environmental pollution, reduce the purpose of production cost, for promoting 6- hydroxyl -8- Lipase Catalyzed Resolution of Racemic Ethyl
Economic technology development have practical significance.
Summary of the invention
It is an object of the invention to overcome the deficiencies of existing technologies, according to the synthesis theory of Green Chemistry, provide a kind of new
6- hydroxyl -8- Lipase Catalyzed Resolution of Racemic Ethyl preparation method, and handle reaction caused by waste water containing boron.This method economy, environmental protection, have
Conducive to the industrialized production of the product, and the economic technology of 6- hydroxyl -8- Lipase Catalyzed Resolution of Racemic Ethyl can be promoted to develop.
For achieving the above object, the present invention adopts the following technical scheme:
6- oxo -8- Lipase Catalyzed Resolution of Racemic Ethyl is dissolved in dichloroethanes, and temperature is maintained at 10~30 DEG C, and phase transfer catalysis (PTC) is added
Sodium borohydride ammonia spirit is added dropwise in agent, reacts 2~4 hours, filtering layering, organic layer salt acid for adjusting pH=5~6, and vacuum is dense
Contract to obtain 6- hydroxyl -8- Lipase Catalyzed Resolution of Racemic Ethyl.Water layer obtains the kodalk being precipitated by filter, and filtrate concentration and recovery ammonium hydroxide is cold
But it crystallizes, filtering obtains kodalk again.
The phase transfer catalyst is the quaternary ammonium salts phases such as tetrabutylammonium bromide, tetrabutylammonium chloride, 4-butyl ammonium hydrogen sulfate
Transfer catalyst, preferably tetrabutylammonium bromide.
6- oxo -8- the Lipase Catalyzed Resolution of Racemic Ethyl: tetrabutylammonium bromide: sodium borohydride mass ratio are as follows: 1:0.01~0.05:
0.05~0.08
The ammonia concn are as follows: 5%~17%
Water layer processing method after the reduction reaction are as follows:
1. water layer obtains the kodalk solid being precipitated by filter after reacting；
2. filtrate is put into the concentration tank equipped with recyclable device, 100 DEG C of recycling ammonium hydroxide；
3. water temperature is down to 30 DEG C or less is precipitated kodalk solid again；
4. removing the kodalk that mother liquor is precipitated, merges dry and recycle with the 1. middle kodalk obtained；
5. by the filtrated stock that kodalk has been precipitated be added to next group waste water containing boron processing step 2. in.
Water layer processing method after reduction reaction provided by the invention, it is about every that the step boils off water when 1. recycling ammonium hydroxide
Criticize the 50%-75% of reduction gained water layer weight.
The present invention also provides the equipment that water layer after a kind of reduction reaction recycles, the equipment includes:
Filter 1 removes the kodalk solid that water layer has been precipitated；
Concentration and recovery tank inputs water layer after reduction reaction, recycles ammonium hydroxide；
Cold analysis tank, is directly connected to filter, will recycle the concentrate after ammonium hydroxide and has cooled down；
Filter 2 removes the kodalk solid that mother liquor is precipitated；
Circulating line applies mother liquor, and recycles ammonium hydroxide and then return in reaction step and use.
The present invention also provides the equipment that water layer after a kind of reduction reaction recycles, feature further includes that pipeline connection is suitable
Sequence are as follows: filter 1, concentration and recovery tank (connecing condenser, receiving tank, spray absorption tower), cold analysis tank, filter 2；Filter is used
Pipeline is connect with concentration and recovery tank, is used for Recycling Mother Solution.
Due to using the technology described above, compared with the prior art, advantage is mainly that synthesis step is succinct to the present invention, is subtracted
The use for having lacked organic solvent, avoids direct discharging of waste water, so that the kodalk generated is easily isolated, it will not be with other objects
Qualitative response has successfully been recycled kodalk solid, has in addition also been recycled to ammonium hydroxide.Particularly, inclined by recycling
Boratex, for industrially by boron element, further recycling prepares sodium borohydride, recycling boron element acquisition, create can
Energy.Entire technique meets green syt and technology requirement, is suitable for large-scale industrial production.
Detailed description of the invention
For the above objects, features and advantages of the present invention can be clearer and more comprehensible, below in conjunction with attached drawing to tool of the invention
Body embodiment elaborates, in which:
Fig. 1 is process flow chart of the invention；
Fig. 2 is reduction reaction water layer processing equipment figure of the present invention；
Attached drawing 2 marks inventory as follows:
1, filter 1,2, concentration and recovery tank, 3, cold analysis tank, 4, filter 2,5, drier, 6, condenser, 7, receiving tank,
8, spray absorption tower.
Specific embodiment
Embodiment 1:
100Kg 6- oxo -8- Lipase Catalyzed Resolution of Racemic Ethyl is dissolved in 500Kg dichloroethanes, temperature is maintained at 10~30 DEG C, adds
Enter 1Kg tetrabutylammonium bromide, 17% ammonia spirit 100Kg of the sodium borohydride containing 5Kg is added dropwise, react 4 hours, filtering layering has
Machine layer hydrochloric acid adjusts pH=5~6, the concentration of 0.1MPa heating under reduced pressure, until 110 DEG C of temperature end, obtain the 6- hydroxyl-of purity 92%
8- Lipase Catalyzed Resolution of Racemic Ethyl concentrate 98Kg.Water layer obtains the kodalk being precipitated, 10% ammonium hydroxide of filtrate concentration and recovery by filter
75Kg reuse, crystallisation by cooling, filtering obtain kodalk again, and mother liquor returns set, merge gained kodalk 13.8Kg, and 100 DEG C dry
Obtain 7.6Kg, purity 95%.
Embodiment 2:
100Kg 6- oxo -8- Lipase Catalyzed Resolution of Racemic Ethyl is dissolved in 500Kg dichloroethanes, temperature is maintained at 10~30 DEG C, adds
Enter 1Kg tetrabutylammonium bromide, 10% ammonia spirit 100Kg of the sodium borohydride containing 8Kg is added dropwise, wherein 75Kg ammonium hydroxide is embodiment 1
Recycling gained, reacts 2 hours, filtering layering, and organic layer hydrochloric acid adjusts pH=5~6,0.1MPa heating under reduced pressure concentration, until temperature
110 DEG C of end are spent, the 6- hydroxyl -8- Lipase Catalyzed Resolution of Racemic Ethyl concentrate 99Kg of purity 90% is obtained.Water layer, which is obtained by filter, to be precipitated
Kodalk, filtrate merge with 1 mother liquor of embodiment, 7% ammonium hydroxide 60Kg of concentration and recovery, crystallisation by cooling, and filtering obtains kodalk again,
Merge gained kodalk 21.5Kg, 100 DEG C dry to obtain 11Kg, purity 98%.
Embodiment 3:
100Kg 6- oxo -8- Lipase Catalyzed Resolution of Racemic Ethyl is dissolved in 500Kg dichloroethanes, temperature is maintained at 10~30 DEG C, adds
Enter 5Kg tetrabutylammonium bromide, 5% ammonia spirit 100Kg of the sodium borohydride containing 8Kg is added dropwise, react 4 hours, filtering layering has
Machine layer hydrochloric acid adjusts pH=5~6, the concentration of 0.1MPa heating under reduced pressure, until 110 DEG C of temperature end, obtain the 6- hydroxyl-of purity 94%
8- Lipase Catalyzed Resolution of Racemic Ethyl concentrate 95Kg.Water layer obtains the kodalk being precipitated by filter, and filtrate recycles 4% ammonium hydroxide 50Kg, together
When mother liquor concentrations, crystallisation by cooling, filtering again kodalk, merge gained kodalk 20.7Kg, 100 DEG C dry
11.1Kg, purity 94%.
It is pointed out that the technical concepts and features of above-mentioned preferred embodiment only to illustrate the invention, its object is to
Those skilled in the art can understand the contents of the present invention and implements accordingly, and protection of the invention can not be limited with this
Range.Any equivalent change or modification in accordance with the spirit of the invention should be covered by the protection scope of the present invention.
Claims (6)
1. preparation and the post-processing approach of a kind of -8 Lipase Catalyzed Resolution of Racemic Ethyl (I) of lipoic acid intermediate 6- hydroxyl:
It is characterized in that the method following steps:
(1) 6- oxo -8- Lipase Catalyzed Resolution of Racemic Ethyl is dissolved in dichloroethanes, temperature is maintained at 10~30 DEG C, and phase transfer catalysis (PTC) is added
Sodium borohydride ammonia spirit is added dropwise in agent, reacts 2~4 hours, and filtering layering, organic layer adjusts pH=5~6 with hydrochloric acid, and vacuum is dense
Contract to obtain -8 Lipase Catalyzed Resolution of Racemic Ethyl of 6- hydroxyl, and water layer post-processing approach is shown in step (2)；
(2) post-processing approach of water layer, comprising:
1. water layer obtains the kodalk solid being precipitated by filter after reacting；
2. filtrate is put into the concentration kettle equipped with recyclable device, 100 DEG C of recycling ammonium hydroxide, and boils off suitable quantity of water；
3. water temperature is down to 30 DEG C or less is precipitated kodalk solid again；
4. removing the kodalk that mother liquor is precipitated, merges dry and recycle with the 1. middle kodalk obtained；
5. will be precipitated kodalk mother liquor be added to next group waste water containing boron processing step 2. in；
Above-mentioned steps boil off the 50%-75% that water is about every batch of reduction gained water layer weight when 1. recycling ammonium hydroxide.
2. the preparation method of lipoic acid intermediate according to claim 1, it is characterised in that: phase used in reduction reaction turns
Shifting catalyst is the quaternary ammonium salts such as tetrabutylammonium bromide, tetrabutylammonium chloride, 4-butyl ammonium hydrogen sulfate.
3. the preparation method of lipoic acid intermediate according to claim 1, it is characterised in that: material 6- oxygen in reduction reaction
Generation -8- Lipase Catalyzed Resolution of Racemic Ethyl: tetrabutylammonium bromide: sodium borohydride mass ratio is 1:0.01~0.05:0.05~0.08.
4. the preparation method of lipoic acid intermediate according to claim 1, it is characterised in that: configuration sodium borohydride ammonia spirit
The ammonia concn used is 5%~17%.
5. the post-processing approach of water layer according to claim 1, it is characterised in that: used water layer after a set of reduction reaction
The equipment recycled, equipment include:
1. filter 1 removes the kodalk solid that water layer has been precipitated；
2. recycling concentration kettle, water layer after reduction reaction is inputted, recycle ammonium hydroxide and boils off suitable water；
3. cold analysis tank, is directly connected to filter, the concentrate after ammonium hydroxide will be recycled and cooled down；
4. filter 2 removes the kodalk solid that mother liquor is precipitated；
5. circulating line applies mother liquor, and recycles ammonium hydroxide and then return in reaction step and use.
6. the equipment that water layer recycles in the post-processing approach of water layer according to claim 5, it is characterised in that: pipeline
The order of connection are as follows: filter 1 is connected with condenser, concentration and recovery kettle, the cold analysis tank, mistake of receiving tank and spray absorption tower
Filter 2；Filter pipeline is connect with concentration and recovery kettle, is used for Recycling Mother Solution.
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| CN108373411A (en) * | 2017-12-16 | 2018-08-07 | 山东新华制药股份有限公司 | The preparation method of high-purity 4- chloro-3-hydroxyl ethyl butyrates |
| CN114149324B (en) * | 2021-12-07 | 2023-08-22 | 厦门金达威维生素有限公司 | Synthesis method of 6-hydroxy-8-chlorooctanoic acid ethyl ester, 6, 8-dichloro octanoic acid ethyl ester and lipoic acid |
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| Publication number | Priority date | Publication date | Assignee | Title |
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| US2877235A (en) * | 1954-05-28 | 1959-03-10 | Du Pont | Alpha-lipoic acid process |
| US2975198A (en) * | 1954-07-08 | 1961-03-14 | Research Corp | Lipoic acid intermediates |
| CN100593534C (en) * | 2007-09-30 | 2010-03-10 | 浙江工业大学 | Chemical method for synthesizing 6,8-dichloro ethyl cacodylic acid caprylate |
| CN102531299B (en) * | 2012-03-06 | 2013-05-01 | 江苏同禾药业有限公司 | Method for treating addition wastewater in production process of lipoic acid |
| CN102731307B (en) * | 2012-07-17 | 2014-09-03 | 江苏同禾药业有限公司 | Preparation method of ethyl 6-oxo-8-chloro-caprylate |
| CN104261629B (en) * | 2014-10-11 | 2016-03-02 | 江苏同禾药业有限公司 | The combination treatment method of addition waste water and cyclization waste water in production process of lipoic acid |
| CN104671570A (en) * | 2014-12-24 | 2015-06-03 | 江苏同禾药业有限公司 | Method for treating aluminum-containing wastewater in preparation process of 6-oxo-8-chloro ethyl caprylate |
| CN105087681B (en) * | 2015-08-18 | 2019-01-22 | 苏州富士莱医药股份有限公司 | (S) preparation method and application of -6- hydroxyl -8- Lipase Catalyzed Resolution of Racemic Ethyl |
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