CN102627675A - Method for preparing cane sugar-6-ester - Google Patents
Method for preparing cane sugar-6-ester Download PDFInfo
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- CN102627675A CN102627675A CN2012100875521A CN201210087552A CN102627675A CN 102627675 A CN102627675 A CN 102627675A CN 2012100875521 A CN2012100875521 A CN 2012100875521A CN 201210087552 A CN201210087552 A CN 201210087552A CN 102627675 A CN102627675 A CN 102627675A
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Abstract
The invention discloses a method for preparing cane sugar-6-ester, which comprises the following steps of (1) dissolving cane sugar in an organic solvent with the volume which is two to six times of that of the cane sugar, then adding an organic tin compound, stirring and reacting the mixture at 70 DEG C to 130 DEG C, and removing water produced by a reaction by adopting an interval vacuum dewater method till the reaction is completed; (2) after the reaction is completed, adding an acylation reagent under the condition of low temperature to produce the cane sugar-6-ester, adding water to stop the reaction, and finally adding certain amount of cyclohexane to recover the organic tin compound. The method for preparing the cane sugar-6-ester has the advantages of simplifying the recovery process of the solvent and ion liquid, facilitating energy saving and being high in cane sugar conversion rate. The yield and purity of the product cane sugar-6-ester are high, and the cost of a subsequent product sucralose of the cane sugar-6-ester is reduced.
Description
Technical field
The present invention relates to the sucrose-6-ester preparation field, specifically is a kind of method for preparing sucrose-6-ester that vacuum method is removed water generation reaction.
Background technology
Sucrose-6-ester be synthesizing trichloro (4,1 ', 6 '-three chloro-4,1 ', 6 '-three deoxidation gala type sucrose) important intermediate, form through 6 hydroxyls of single radical protection method protection sucrose by sucrose, it is the focus of studying in the sucrose deep processed product simultaneously.At present the difference according to the intermediate preparation method of TGS can be divided into: direct esterification method, ortho ester method, Dibutyltin oxide method.
The direct esterification method is prone to produce how acetylizad sucrose derivative, and product is difficult to separate, and rely on column chromatography for separation, and productive rate is low, is difficult to industriallization.
The ortho ester method is Simpson in 1989 and Tadley (US4,889,928) invention; Utilize the reaction of sucrose and trimethyl orthoacetate to generate sucrose-4; 6 cyclic esters, through adding the water open loop, the 4-ester moves to the 6-ester under alkaline condition again; Obtain the higher sucrose-6-ester of yield at last, the good industrial prospect is arranged.But this method still has a large amount of sucrose unreacteds, and the sucrose-6-ester transformation efficiency is lower, causes foreign matter content big, influences follow-up chlorination reaction, makes the yield of chlorizate sucralose-6-ester and purity on the low side, and aftertreatment technology is complicated.
The Dibutyltin oxide method is utilized highly selective and 6 hydroxyl reactions of sucrose of organic tin compound, subsequently with acylating reagent reaction, thereby obtains the sucrose-6-ester of high yield, has extraordinary industrial prospect.
The Dibutyltin oxide method is that Navia and Juan (US4,950,746) proposed in nineteen ninety; Its method refluxes organotin and sucrose in methyl alcohol, remove methyl alcohol again and obtain 1,3-two-(6-O-sucrose)-1; 1; 3,3-tetraalkyl distannoxane, the following and acylating reagent reaction generation sucrose-6-ester of low temperature then.
U.S. Pat 5; 023; 329 announce the sucrose-6-ester working method: employing DMF is a solvent; Take the water (organic solvent azeotropic removes water law) of generation out of with water azeotropic organic solvent (like hexanaphthene), make the reaction of sucrose and organotin generate sucrose organotin mixture, generate sucrose-6-ester with the reaction of aceticanhydride class acylating reagent again.
Publication number is the working method of the open sucrose-6-ester of Chinese patent of CN101979396: adopt 1; 1; 2-trichloroethane and ionic liquid Tetrabutyl amonium bromide mixed system are as reaction solvent; The limit coronite is removed the water (continous vacuum removes water law) that dereaction generates, and makes the reaction of sucrose and organotin generate sucrose organotin mixture, and last and acylating reagent reaction generates sucrose-6-ester.
U.S. Pat 5; 034; 551 disclose the method that reclaims the organic tin compound in a kind of DMF solution of and sucrose-6-ester: an amount of water of adding in the DMF reaction solution that react; With organic solvent (like hexanaphthene) extraction organic tin compound, concentrate the recyclable organic tin compound of extraction solvent; DMF solution high vacuum is concentrated into dried sucrose-6-ester syrup.
Therefore, the method main points of disclosed employing sucrose and organic tin compound reaction synthesis of sucrose-6-esters are following: 1, reaction medium is the mixed system of amides or chlorinated alkane and ionic liquid composition; 2, the method that dewaters has organic solvent azeotropic to remove water law and continous vacuum removes water law; 3, with the acylating reagent reaction, and add the water stopped reaction, reclaim the organic tin compound with organic solvent extraction.
There is following shortcoming in these methods: 1, the organic solvent usage quantity as reaction medium is big; Though the mixed system that adopts ionic liquid and polar organic solvent is as reaction system; Reduce the usage quantity of organic solvent, but existed ion liquid recovery set to use problem, increased the aftertreatment cost; 2, the mode that dewaters has organic solvent azeotropic to remove water law and continous vacuum removes water law; Organic solvent azeotropic removes water law owing to need extra adding azeotropic organic solvent; Reduce single still charging capacity of sucrose, continous vacuum removes water law vacuum pump continuous service, and the energy consumption waste is serious.
Summary of the invention
The objective of the invention is to be directed against the deficiency that exists with said prior art, more economic and highly purified a kind of method for preparing sucrose-6-ester is provided.
For achieving the above object, technical scheme of the present invention is: a kind of method for preparing sucrose-6-ester, and it step that comprises is following:
(1) with sucrose dissolved in the organic solvent of 2～6 times of its volumes, add the organic tin compound then, 70～130 ℃ of stirring reactions adopt intermittent vacuum to remove water law and remove the water that reaction generates, until reacting completely;
(2) back that reacts completely adds acylating reagent and generates sucrose-6-ester under 0～10 ℃ coldcondition, adds the water stopped reaction, adds the hexanaphthene recovery organic tin compound catalyst of 4～12 times of sucrose weight at last according to the charging capacity of sucrose.
Said intermittent vacuum except that the step that water law comprises is: start vacuum pump after 1～4 hour at stirring reaction and vacuumize the water that generates except that dereaction; Stop vacuum pump and continue reaction 1～4 hour; Restarting vacuum pump vacuumizes and dewaters; Repeat aforesaid operations 2～6 times, detect until reacting completely with some plate or HPLC.
Said vacuum remove water that dereaction generates-0.065～-carry out under the 0.099MPa pressure.
The water that said reaction generates is N, the mixture of dinethylformamide and water.
The preferred N of said organic solvent, dinethylformamide (DMF).
Said consumption of organic solvent is 3～5 times of sucrose volume.
Said organic tin compound is selected from Dibutyltin oxide and 1,3-diacetoxy-1,1,3, and a kind of in the 3-tetrabutyl distannoxane, the amount of organic tin compound is 105～110% of a sucrose molar weight.
Said acylating reagent is selected from a kind of in aceticanhydride, the benzoyl oxide.
The temperature of stirring reaction is preferably 75～95 ℃.
The water that said vacuum is removed the dereaction generation is 0～30% of initial adding organic solvent amount.
Wherein vacuum is preferably 3～4 times except that the number of times of the water of dereaction generation.
Compared with prior art, the invention has the beneficial effects as follows:
1) reaction medium is single amides N, and dinethylformamide avoids the use of the mixed system that chlorinated alkane and ionic liquid are formed, and simplifies solvent and ion liquid recovery process.
2) adopt intermittent vacuum to remove water law and remove the water that reaction generates, avoid the use of organic solvent azeotropic and remove water law, improve the sucrose charging capacity; Equally also avoid using continous vacuum to remove water law; Help energy-conservationly, energy-conservationly be mainly reflected in following two aspects: the DMF amount that 1,1 kilogram of sucrose of every throwing is corresponding reduces, and the DMF that promptly need concentrate the preparation esterifying liquid measures corresponding minimizing; And part DMF was removed in the vaccum dewatering stage, saved concentration time; 2, the time of continous vacuum method operation vacuum pump is by the required time decision of reaction; But in fact sucrose organotin mixture is generated as a reversible equilibrium process; Promptly sucrose organotin mixture can exist under certain water-content; From high boiling organic solvent, remove to anhydrate simultaneously certain minimum water-content requirement is also arranged; Vaccum dewatering weak effect when water-content is low, so question response generates water and reaches the amount that a large amount of sucrose organotin mixtures can exist and need one period than length, and can need not to move vacuum pump during this period of time.
3) adopt the intermittent vacuum legal system that dewaters to be equipped with sucrose-6-ester, the sucrose inversion rate is high, and the yield of product sucrose-6-ester and purity height, has reduced the cost of its subsequent product TGS.
Embodiment
Among the present invention, sucrose organo-tin compound and sucrose-6-ester adopt HPLC to analyze, and the content of tin in the x-ray fluorescence analysis hexanaphthene layer is adopted in the recovery analysis of organotin catalysts, and converting obtains again.
Embodiment 1
50g sucrose and 300mlDMF are added in the four-hole bottle, and 75 ℃ of stirring in water bath dissolvings also add the positive Dibutyltin oxide of 55g, and 75 ℃ of stirring reaction 2h vacuumize under-0.09MPa the condition, reclaim DMF30ml; Continue reaction 1h, vacuum reclaims DMF30ml; It is qualified until Liquid Detection to repeat above-mentioned steps again, and reaction solution is cooled to 0～10 ℃, slowly drips the 15ml diacetyl oxide, drips complete stirring reaction 1h, rises to the stirring at room reaction again until reacting completely.Add the purified water stopped reaction, and add hexanaphthene (200ml * 3 time) extraction and reclaim catalyzer, organotin can add alkali and reclaims positive Dibutyltin oxide in the hexanaphthene, and the recovery is 95%; The DMF of lower floor contains sucrose-6-ethyl ester mutually, detects through HPLC to contain 46.5g, and molar yield is 82.9%.
Embodiment 2
Except that the DMF consumption is adjusted into the 150mL, remaining method is all identical with embodiment 1 with condition, detects through HPLC, finally obtains sucrose-6-ethyl ester 42.9g, and molar yield is 76.6%.
Embodiment 3
50g sucrose and 200mlDMF are added in the four-hole bottle, and 95 ℃ of stirring in water bath also add 110g1,3-diacetoxy-1,1; 3,3-tetrabutyl distannoxane, 95 ℃ of stirring reaction 2h vacuumize under-0.08MPa the condition; Reclaim DMF60ml, continue reaction 1h, reclaim DMF 30ml; It is qualified until Liquid Detection to repeat above-mentioned steps again, and reaction solution is cooled to 0-10 ℃, slowly drips the 15ml diacetyl oxide, drips complete stirring reaction 1h, rises to the stirring at room reaction again until reacting completely.Add the purified water stopped reaction, and add hexanaphthene (200ml * 3 time) extraction and reclaim catalyzer, be concentrated into do recyclable 1,3-diacetoxy-1,1,3,3-tetrabutyl distannoxane, the recovery 98.5%; The DMF of lower floor contains sucrose-6-ethyl ester mutually, measures through HPLC to contain 49.2g, and molar yield is 87.8%.
Embodiment 4
Remove 1,3-diacetoxy-1,1,3, outside 3-tetrabutyl distannoxane employing recovery set was used, remaining method was all identical with embodiment 3 with condition, detects through HPLC, finally obtains sucrose-6-ethyl ester 48.3g, and molar yield is 86.2%.
Embodiment 5
50g sucrose and 300mlDMF are added in the four-hole bottle, and 85 ℃ of stirring in water bath also add the positive Dibutyltin oxide of 55g, and 85 ℃ of stirring reaction 2h vacuumize under-0.09MPa the condition, reclaim DMF40ml, continue reaction 1h, reclaim DMF30ml; It is qualified until Liquid Detection to repeat above-mentioned steps again, and reaction solution is cooled to 0-10 ℃, slowly drips the 30.3ml phenylacetic anhydride, drips complete stirring reaction 1h, rises to the stirring at room reaction again until reacting completely.Add the purified water stopped reaction, and add hexanaphthene (200ml * 3 time) extraction and reclaim catalyzer, be concentrated into to do and reclaim 1,3-diacetoxy-1,1,3,3-tetrabutyl distannoxane, the recovery 99.2%; The DMF of lower floor contains sucrose-6-phenylacetate mutually, and HPLC measures and contains 58.9g, and molar yield is 90.4%.
Located detailed embodiment of the present invention though preceding text have shown, obvious, the content that the preceding text description is mentioned not is as limitation of the present invention only as illustrative case.Those skilled in the art is under prerequisite of the present invention, can carry out that part is revised and change, but a kind of high yield with technical characterictic described herein prepares the method for sucrose-6-ester class, all falls into the protection domain of this patent.
Claims (10)
1. a method for preparing sucrose-6-ester is characterized in that, may further comprise the steps:
(1) with sucrose dissolved in the organic solvent of 2～6 times of its volumes, add the organic tin compound then, 70～130 ℃ of stirring reactions adopt intermittent vacuum to remove water law and remove the water that reaction generates, until reacting completely;
(2) under coldcondition, add acylating reagent and generate sucrose-6-ester, add the water stopped reaction, add hexanaphthene at last and reclaim the organic tin compound.
Said intermittent vacuum except that the step that water law comprises is: start the vacuum pump vacuum after 1～4 hour at stirring reaction and remove the water that dereaction generates; Stop vacuum pump and continue reaction 1～4 hour; Restart vacuum pump and vacuumize and dewater, repeat aforesaid operations 2～6 times until reacting completely.
2. a kind of method for preparing sucrose-6-ester as claimed in claim 1 is characterized in that, said consumption of organic solvent is that 3～5 times of the sucrose volume or said (2) step are under 0～10 ℃ coldcondition, to add acylating reagent generation sucrose-6-ester.
3. a kind of method for preparing sucrose-6-ester as claimed in claim 2 is characterized in that said organic solvent is N, dinethylformamide.
4. a kind of method for preparing sucrose-6-ester as claimed in claim 1; It is characterized in that said organic tin compound is selected from Dibutyltin oxide and 1,3-diacetoxy-1; 1; 3, a kind of in the 3-tetrabutyl distannoxane, the amount of organic tin compound is 105～110% of a sucrose molar weight.
5. a kind of method for preparing sucrose-6-ester as claimed in claim 1 is characterized in that, said acylating reagent is selected from a kind of in aceticanhydride, the benzoyl oxide.
6. like claim 3,4 or 5 described a kind of methods that prepare sucrose-6-ester, it is characterized in that the temperature of stirring reaction is 75～95 ℃.
7. a kind of method for preparing sucrose-6-ester as claimed in claim 6 is characterized in that, said vacuum remove water that dereaction generates-0.065～-carry out under the 0.099MPa pressure.
8. a kind of method for preparing sucrose-6-ester as claimed in claim 7 is characterized in that, the water that said reaction generates is N, the mixture of dinethylformamide and water.
9. a kind of method for preparing sucrose-6-ester as claimed in claim 8 is characterized in that, the water that said vacuum is removed the dereaction generation is 0～30% of initial adding organic solvent amount.
10. a kind of method for preparing sucrose-6-ester as claimed in claim 8 is characterized in that, wherein vacuum is 3～4 times except that the number of times of the water of dereaction generation.
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| CN2012100875521A CN102627675A (en) | 2012-03-29 | 2012-03-29 | Method for preparing cane sugar-6-ester |
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| CN2012100875521A CN102627675A (en) | 2012-03-29 | 2012-03-29 | Method for preparing cane sugar-6-ester |
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Cited By (11)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN104387427A (en) * | 2014-10-30 | 2015-03-04 | 安徽金禾实业股份有限公司 | Method for producing sucralose |
| CN104774226A (en) * | 2015-04-08 | 2015-07-15 | 常州市牛塘化工厂有限公司 | Preparation method of saccharose-6-ethyl ester |
| CN104817597A (en) * | 2015-05-22 | 2015-08-05 | 盐城捷康三氯蔗糖制造有限公司 | Preparation method of sucrose-6-ester |
| CN105111246A (en) * | 2015-08-22 | 2015-12-02 | 安徽金禾实业股份有限公司 | Method for recycling organic tin in sucralose production |
| CN106349300A (en) * | 2016-08-30 | 2017-01-25 | 安徽金禾实业股份有限公司 | Method for reaction of sucralose esterified single solvent |
| CN106632533A (en) * | 2016-12-09 | 2017-05-10 | 福建科宏生物工程股份有限公司 | Low-temperature and efficient preparation method of sucrose-6-acetate |
| CN106831436A (en) * | 2017-01-17 | 2017-06-13 | 江西师范大学 | A kind of method of preparation and its removing of sugared hydroxyl protecting group dimethyl benzene acetyl group DMNA |
| CN109438533A (en) * | 2018-12-10 | 2019-03-08 | 安徽金禾实业股份有限公司 | A kind of method of Sucralose production high temperature continuous acylation |
| CN109734755A (en) * | 2018-12-28 | 2019-05-10 | 山东三和维信生物科技有限公司 | A kind of Sucralose crystallization processes |
| WO2022051988A1 (en) * | 2020-09-10 | 2022-03-17 | 安徽金禾实业股份有限公司 | Method for preparing sucrose-6-ester |
| WO2022155909A1 (en) * | 2021-01-22 | 2022-07-28 | 安徽金禾实业股份有限公司 | Production device and production method for sucrose-6-ester |
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| US5023329A (en) * | 1990-04-23 | 1991-06-11 | Noramco, Inc. | Sucrose-6-ester production process |
| US5034551A (en) * | 1990-04-23 | 1991-07-23 | Noramco, Inc. | Process for recovery of organotin esters from reaction mixtures containing the same and re-use of the recovered organotin compounds |
| CN101979396A (en) * | 2010-10-13 | 2011-02-23 | 南京甘倍加生物科技有限责任公司 | Method for synthesizing sucrose-6-ester and sucralose |
| CN102365292A (en) * | 2009-03-31 | 2012-02-29 | 塔特和莱利技术有限公司 | Base-assisted formation of tin-socrose adducts |
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2012
- 2012-03-29 CN CN2012100875521A patent/CN102627675A/en active Pending
Patent Citations (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US5023329A (en) * | 1990-04-23 | 1991-06-11 | Noramco, Inc. | Sucrose-6-ester production process |
| US5034551A (en) * | 1990-04-23 | 1991-07-23 | Noramco, Inc. | Process for recovery of organotin esters from reaction mixtures containing the same and re-use of the recovered organotin compounds |
| CN102365292A (en) * | 2009-03-31 | 2012-02-29 | 塔特和莱利技术有限公司 | Base-assisted formation of tin-socrose adducts |
| CN101979396A (en) * | 2010-10-13 | 2011-02-23 | 南京甘倍加生物科技有限责任公司 | Method for synthesizing sucrose-6-ester and sucralose |
Cited By (12)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN104387427A (en) * | 2014-10-30 | 2015-03-04 | 安徽金禾实业股份有限公司 | Method for producing sucralose |
| CN104774226A (en) * | 2015-04-08 | 2015-07-15 | 常州市牛塘化工厂有限公司 | Preparation method of saccharose-6-ethyl ester |
| CN104817597A (en) * | 2015-05-22 | 2015-08-05 | 盐城捷康三氯蔗糖制造有限公司 | Preparation method of sucrose-6-ester |
| CN105111246A (en) * | 2015-08-22 | 2015-12-02 | 安徽金禾实业股份有限公司 | Method for recycling organic tin in sucralose production |
| CN106349300A (en) * | 2016-08-30 | 2017-01-25 | 安徽金禾实业股份有限公司 | Method for reaction of sucralose esterified single solvent |
| CN106349300B (en) * | 2016-08-30 | 2019-02-26 | 安徽金禾实业股份有限公司 | Sucralose is esterified single solvent reaction method |
| CN106632533A (en) * | 2016-12-09 | 2017-05-10 | 福建科宏生物工程股份有限公司 | Low-temperature and efficient preparation method of sucrose-6-acetate |
| CN106831436A (en) * | 2017-01-17 | 2017-06-13 | 江西师范大学 | A kind of method of preparation and its removing of sugared hydroxyl protecting group dimethyl benzene acetyl group DMNA |
| CN109438533A (en) * | 2018-12-10 | 2019-03-08 | 安徽金禾实业股份有限公司 | A kind of method of Sucralose production high temperature continuous acylation |
| CN109734755A (en) * | 2018-12-28 | 2019-05-10 | 山东三和维信生物科技有限公司 | A kind of Sucralose crystallization processes |
| WO2022051988A1 (en) * | 2020-09-10 | 2022-03-17 | 安徽金禾实业股份有限公司 | Method for preparing sucrose-6-ester |
| WO2022155909A1 (en) * | 2021-01-22 | 2022-07-28 | 安徽金禾实业股份有限公司 | Production device and production method for sucrose-6-ester |
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Application publication date: 20120808 |