USH708H - Method of producing diacetone sorbose - Google Patents

Method of producing diacetone sorbose Download PDF

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Publication number
USH708H
USH708H US07/035,847 US3584787A USH708H US H708 H USH708 H US H708H US 3584787 A US3584787 A US 3584787A US H708 H USH708 H US H708H
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United States
Prior art keywords
acetone
reaction
sorbose
water
reactor
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Abandoned
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US07/035,847
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English (en)
Inventor
Youichi Oka
Hitoshi Sawada
Masao Yokoyama
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Takeda Pharmaceutical Co Ltd
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Takeda Chemical Industries Ltd
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Assigned to TAKEDA CHEMICAL INDUSTRIES, LTD. reassignment TAKEDA CHEMICAL INDUSTRIES, LTD. ASSIGNMENT OF ASSIGNORS INTEREST. Assignors: OKA, YOUICHI, SAWADA, HITOSHI, YOKOYAMA, MASAO
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Publication of USH708H publication Critical patent/USH708H/en
Abandoned legal-status Critical Current

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    • C—CHEMISTRY; METALLURGY
    • C07—ORGANIC CHEMISTRY
    • C07H—SUGARS; DERIVATIVES THEREOF; NUCLEOSIDES; NUCLEOTIDES; NUCLEIC ACIDS
    • C07H9/00—Compounds containing a hetero ring sharing at least two hetero atoms with a saccharide radical
    • C07H9/02—Compounds containing a hetero ring sharing at least two hetero atoms with a saccharide radical the hetero ring containing only oxygen as ring hetero atoms
    • C07H9/04—Cyclic acetals

Definitions

  • This invention relates to a method of producing 2,3:4,6-di-O-isopylidene-L-sorbofuranose.
  • 2,3:4,6-di-O-isopylidene-L-sorbofuranose which is herein briefly referred of as diacetone sorbose, is an important intermediate for the production of L-ascorbic acid, and is obtained by reacting L-sorbose with acetone in the presence of a ketal formation catalyst.
  • a diversity of methods for producing diacetone sorbose are already known, however, all of the prior methods are attended by various defects. For instance, there is an well-known method in which concentrated sulfuric acid is used as a ketal formation catalyst. In this method, since the concentrated sulfuric acid is used also as a dehydrating agent, the acid is used in large amounts, usually in amounts of about 80-100% by weight of L-sorbose used. Therefore, the recovery of the resultant diacetone sorbose needs a step of neutralizing the sulfuric acid with a suitable alkali, and thus a step of disposal of large amounts of the resultant salts of the acid.
  • ketal formation reaction is a dehydration condensation reaction of L-sorbose with acetone, and is an equilibrium reaction, it is already known that the removal of the water produced in the reaction improves the yields of diacetone sorbose. Therefore, a further method is known, as is described in U.S. Pat. No. 3,607,862, in which L-sorbose is reacted with acetone in the presence of perchloric acid as a ketal formation catalyst in an inert organic solvent immiscible with water such as hydrocarbons or halogenated hydrocarbons at reflux temperatures under reduced pressures, while continuously removing water produced in the reaction as azeotropic mixtures with the solvent from the reaction mixture.
  • the method uses a solvent in addition to acetone, and it might have an harmful influence upon the reaction, but also the method needs installations to recover and purify the solvent as well as acetone, resulting in a high production cost of diacetone sorbose.
  • a further method is also known, as is described in U.S. Pat. Nos. 4,460,767 and 4,464,530 in which L-sorbose is reacted with acetone in the presence of a catalyst such as a hydrogen halide or a cupric halide while removing water generated in the reaction as a mixture thereof with acetone.
  • a catalyst such as a hydrogen halide or a cupric halide
  • this method also has a defect in that very large amounts of acetone must be evaporated, usually in amounts of at least about 250 times the weight of L-ascorbic acid used, to efficiently remove the reaction water from the reaction mixture. Therefore, the method needs a large scale installations, and consumes large amounts of heat energy.
  • the inventors have made an extensive investigation to solve the problems as above, and have found out that the use of highly dehydrated acetone as additive acetone to compensate the amount of acetone removed from the reaction mixture together with the reaction water makes the amount of the catalyst and acetone needed in the reaction much smaller, and the yields of diacetone sorbose higher as well.
  • an object of the invention to provide a method of producing diacetone sorbose which gives diacetone sorbose in higher yields by use of smaller amounts of catalysts and acetone than in the prior methods.
  • the method of producing diacetone sorbose by reacting L-sorbose with acetone in the presence of a ketal formation catalyst in acetone comprises: carrying out the reaction while continuously removing water generated in the reaction together with acetone and continuously adding to the reaction mixture dehydrated acetone of which water content is not more than about 100 ppm.
  • L-sorbose, acetone and a ketal formation catalyst are fed into a reactor, and the reaction is carried out at reflux temperatures preferably under reduced pressures.
  • the amount of acetone initially fed into a reactor is usually in the range of about 6-25 times, preferably about 10-14 times the weight of L-sorbose fed into the reactor.
  • the initial acetone may contain water in amounts of about 1500 ppm or more, and accordingly commercially available acetone is usable.
  • the use of highly dehydrated acetone having an water content of not more than about 100 ppm is preferred, and acetone having an water content of not more than about 50 ppm is most preferred.
  • the ketal formation catalysts usable in the method of the invention are not specifically limited, and any catalyst is usable which is known in the production of diacetone sorbose, such as concentrated sulfuric acid, hydrochloric acid, perchloric acid, ferric chloride or ferric bromide; or cupric chloride or cupric bromide as described in Japanese Patent Disclosure Unexamined No. 58-55494 and U.S. Pat. No. 4,460,767; copper, iron, their oxides or salts, or hydrogen halides as described in Japanese Patent Disclosure Unexamined No. 58-167583 and U.S. Pat. No. 4,460,767 iodine or hydrogen iodide as described in Japanese Patent Disclosure Unexamined No.
  • the catalyst may be used in smaller amounts than in the prior methods.
  • concentrated sulfuric acid may be used in amounts of about 3-10% by weight of L-sorbose used, namely the amount is about one tenths times or less the amount used in the prior methods where hydrous acetone containing about 1500 ppm or more of water is used.
  • perchloric acid, iodine or hydrogen iodide is used, the amount thereof may be in the same range as that used in the prior methods, however, diacetone sorbose may be produced in the same yields as in the prior methods even by use of the catalyst in amounts of about one fifths times the amount used in the prior methods under the otherwise same reaction conditions.
  • the reaction is carried out while continuously removing the water produced in the reaction, i.e., the reaction water, together with acetone, and at the same time continuously adding highly dehydrated additive acetone which has an water content of not more than about 100 ppm, preferably about 50 ppm, to the reaction mixture.
  • the commercially available acetone contains water usually in amounts of about 1500 ppm or more. It is dehydrated to a water content of not more than about 100 ppm, preferably to not more than about 50 ppm, whereupon it is usable as the additive acetone in the invention.
  • the commercial acetone may be dehydrated preferably with zeolite which has pores of about 3 Angstrom in average diameter and contains water in amounts not more than about 4% by weight.
  • the zeolites usable are not specifically limited, however, such zeolites as have been activated by treating with air or inert gases such as nitrogen, carbon dioxide or argon at temperatures of about 200°-300° C. are preferably used.
  • air or inert gases such as nitrogen, carbon dioxide or argon at temperatures of about 200°-300° C.
  • the zeolite thus treated is placed in a column in amounts in accordance with the amount and the water content of hydrous acetone to be dehydrated, and the hydrous acetone is passed through the column, to provide highly dehydrated acetone.
  • the amount needed is about 20 times the breaking load of dehydration so as to provide highly dehydrated acetone.
  • a column used has preferably a cross section so that hydrous acetone may pass therethrough at a linear velocity of 2-4 m/hr, and the hydrous acetone is passed through the column at a space velocity preferably of not more than about 2 so that the hydrous acetone is effectively contacted with the zeolite.
  • the reaction water is removed as a mixture of the water with acetone from the reaction mixture by distillation, and such a distillate of the mixture of the water with acetone, i.e., hydrous acetone, usually contains water in very small amounts, for example, in amounts of about 200-5000 ppm. Therefore, the rate of the removal of the water from the reaction mixture may be determined by the rate at which the hydrous acetone is distilled off from the reaction mixture in industrial application of the invention, while dehydrated additive acetone is added to the reaction mixture in a rate approximately corresponding to the rate at which the hydrous acetone is distilled off, preferably at a rate substantially the same as the rate of distillation of the hydrous acetone, as is described hereinafter.
  • the hydrous acetone is distilled off preferably at a rate of about 0.5-2 times the initial amount of the acetone fed into a reactor per hour, and most preferably at a rate of about 0.8-1.2 times.
  • hydrous acetone which contains the reaction water is continuously removed from the reaction mixture as above, dehydrated acetone of which water content is not more than about 100 ppm be continuously added to the reaction mixture at a rate which is approximately corresponding to the rate at which the hydrous acetone is distilled off from the reaction mixture.
  • the rate of the removal of the hydrous acetone is preferably substantially the same as the rate of distillation of the hydrous acetone, thereby to keep the concentration of the reaction mixture substantially constant.
  • the reaction temperatures and pressures are so selected that the water formed in the reaction is removed efficiently.
  • the temperature is preferably about 30°-50° C. and the pressure is preferably about 300-500 Torr.
  • Most preferably the reaction is carried out at temperatures of about 40°-45° C. under reduced pressures of 400-450 Torr.
  • the vapor recompression system is advantageously adopted to remove the reaction water together with acetone.
  • the system per se is already well known as a system in which a vapor generated in an evaporator is recompressed to utilize to heat the vapor itself.
  • the application of the system to the production of diacetone sorbose is fully described in the common assignee's preceding U.S. Pat. application Ser. No. 788,433.
  • the single drawing illustrates an example of an apparatus system diagram for carrying out the reaction according to the method of the invention wherein the vapor recompression system is made use of.
  • the apparatus includes a reactor 11 and an evaporator 12 which is connected to the reactor through a circulating pipe 13 equipped with a circulating pump 14.
  • the evaporator has a vacuum pump 15 connected thereto and may be, for example, a plate type evaporator which is provided with a heating means such as plates 16 therein.
  • the reactor, the evaporator and the pipe thus form a loop circuit for circulation of the reaction mixture.
  • the evaporator 12 is communicating with a gas-liquid separator 17, which is communicating with the plates 16 through a vapor pipe 18 equipped with a compressor 19.
  • the plates are at the lower part connected through a condensate pipe 20 to a dehydrator 21, which is in turn connected to the reactor 11 through a return pipe 22 equipped thereon with a pump 23 and a preheater 24.
  • the reactor, the separator, the dehydrator and the plates thus form a vapor recompression and acetone circulating system.
  • L-sorbose, acetone and a ketal formation catalyst are fed into the reactor, and mixed together therein.
  • the vacuum pump 15 is operated to reduce the pressure inside the evaporator and the reactor to a predetermined value.
  • the reaction mixture is circulated between the reactor and the evaporator through the beforesaid loop with the pump 14, and at the initial stage of the reaction, steam, for example, is supplied into the plates of the evaporator to heat the reaction mixture therein, thereby to start the reaction.
  • the temperature of the mixture gradually increases in this way, whereupon the reaction starts, and part of acetone and water formed during the reaction begin to evaporate together.
  • the amount of the vapor gradually increases as the reaction proceeds, to heat the separator and the compressor.
  • the supply of the steam to the plates of the evaporator is discontinued, while the vapor, alter having been subjected to the gas-liquid separation in the separator 17, is supplied into the plates to heat the reaction mixture in the evaporator 17.
  • the apparatus system functions as a reactor and evaporator of the vapor recompression type, to allow the reaction to proceed in a stable and steady manner.
  • the vapor produced in the evaporator is a mixture of vapors of acetone and the reaction water, and it contains water in amounts usually of about 200-5000 ppm, although varying depending upon the reaction conditions.
  • the vapor is then subjected to the gas-liquid separation in the separator, as described hereinbefore, and then is pressurized in the compressor, which may be of the Roots type or of the turbo type, for instance.
  • the vapor now with an increased enthalpy, is fed into the plates of the evaporator, to supply heat to the reaction mixture, and then is introduced, usually as a drain, to the dehydrator 21.
  • the compression rate of the vapor is selected depending upon the elevation of boiling points of the reaction mixture, the mechanical efficiency in the vapor compression and other factors. However, the compression rate is generally not more than about 2, and the rate of about 1.4-1.6, for example, is preferable in most cases.
  • the reaction is continued in a stable and steady manner by supplying dehydrated additive acetone whose water content is not more than about 100 ppm, preferably not more than about 50 ppm, at a rate approximately corresponding to the rate at which acetone is removed as hydrous acetone from the reaction mixture, to the evaporator via the return pipe 23 with the pump 23 and the preheater 24.
  • the drain i.e., hydrous acetone
  • the dehydrator so as to provide highly dehydrated acetone to an water content of not more than about 100 ppm, preferably of not more than about 50 ppm, and to add this dehydrated acetone as an additive acetone to the reaction mixture from the viewpoint of industrial process economy.
  • the hydrous acetone may be dehydrated to such levels as above by use of, for example, zeolite, as described hereinbefore.
  • vapor recompression systems may be adopted in the invention.
  • plate or tubular type evaporators may be used.
  • the manners in which the reaction mixture is circulated may be selected suitably in consideration of the characters of the reaction and the properties of the reaction mixture.
  • the reaction mixture may he forced to flow downwardly in the evaporator or allowed to spontaneously flow downwardly. It is also possible to control the concentrations of the reaction mixture and the rates of the reaction by adjusting the amount of the dehydrated acetone to the reaction mixture.
  • the reaction may be carried out in a continuous manner while continuously removing the water together with acetone, or may be carried out in a batchwise manner.
  • diacetone sorbose may be recovered and purified in conventional manners.
  • an amount of alkali such as sodium hydroxide of about 1.1 times the equivalent to the acid used in the reaction is added to the resultant reaction mixture, acetone is distilled off therefrom, the resultant aqueous solution is extracted with benzene, and the extract is concentrated to dryness, to give crystals of diacetone sorbose.
  • the invention is featured in the use of acetone of which water content is not more than about 100 ppm, and the invention makes in possible to produce diacetone sorbose in higher yields by using a smaller amount of acetone and a ketal formation catalyst.
  • the method of the invention needs only a very small amount of alkalis to neutralize the acid after the reaction, and hence produces only a very small amount of the salts, so that the method makes the recovery and purification of the product very easy and feasible.
  • the method permits an efficient removal of the reaction water together with acetone, and therefore, when perchloric acid, for example, is used as a ketal formation catalyst, the amount of acetone needed is smaller than in the prior methods.
  • perchloric acid for example
  • the amount of acetone needed is smaller than in the prior methods.
  • the yields of diacetone sorbose are remarkably improved.
  • zeolite Zeoram 3AGS by Toyo Soda K.K., Japan
  • zeolite Zeoram 3AGS by Toyo Soda K.K., Japan
  • 1100 g of the zeolite was filled in a column of 30 mm in diameter and 2000 mm in height, and 15 l of commercial acetone containing water in amounts of 2000 ppm were passed through the column at a space velocity of 2, to provide highly dehydrated acetone containing water in amounts of 40 ppm.
  • the resultant reaction mixture was neutralized with a 30% aqueous solution of sodium hydroxide in amounts of 1.1 times the amount of the sulfuric acid used, and then the acetone in the mixture was distilled off.
  • the resultant aqueous solution was then extracted with benzene, to provide a benzene solution of diacetone sorbose, followed by the evaporation of the solution to dryness, to provide 127.1 g (88.0% yield) of diacetone sorbose.
  • the reaction was carried out at temperatures of 30° C., 35° C. or 40° C. for 12 hours, and the otherwise in the same manner as in Example 1, to provide diacetone sorbose.
  • the yields are 86.4%, 86.0% and 88.6%, respectively.
  • An amount of 200 ml of commercial hydrous acetone containing water in amounts of 1500 ppm, 10.0 g of L-sorbose and 127 mg of iodine were placed in a reactor provided with a cooling tube and a drying tube of 2 cm in diameter and 13 cm in length interposed between the reactor and the cooling tube.
  • the drying tube had 30 g of Molecular Sieves 3A (Wako Junyaku Kogyo K.K., Japan) filled therein to dehydrate refluxed solvent during the reaction.
  • Hydrous acetone having water contents in the range of 200-3000 ppm was passed through the column at a rate of 1500 l per hour, namely at a space velocity of 1.5 and a linear velocity of 2 m/hour, to provide 6325 l of highly dehydrated acetone whose water content was not more than 50 ppm.
  • the temperature inside the plates of the evaporator reached 55.5° C. in about 60 minutes, and then hydrous acetone was distilled off at a rate of about 500 kg/hr which was found to contain water in amounts of about 200-3000 ppm, while the dehydrated acetone as obtained above was healed to about 46° C. and supplied into the evaporator at substantially the same rate at which the acetone was distilled off from the reaction mixture.
  • the reaction was carried out in this way at a temperature of 46° C. for 9 hours.

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  • Chemical & Material Sciences (AREA)
  • Organic Chemistry (AREA)
  • Engineering & Computer Science (AREA)
  • Health & Medical Sciences (AREA)
  • Biochemistry (AREA)
  • Biotechnology (AREA)
  • General Health & Medical Sciences (AREA)
  • Genetics & Genomics (AREA)
  • Molecular Biology (AREA)
  • Life Sciences & Earth Sciences (AREA)
  • Saccharide Compounds (AREA)
  • Organic Low-Molecular-Weight Compounds And Preparation Thereof (AREA)
  • Low-Molecular Organic Synthesis Reactions Using Catalysts (AREA)
US07/035,847 1986-04-17 1987-04-08 Method of producing diacetone sorbose Abandoned USH708H (en)

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
JP61-89296 1986-04-17
JP8929686 1986-04-17

Publications (1)

Publication Number Publication Date
USH708H true USH708H (en) 1989-11-07

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US (1) USH708H (da)
JP (1) JPH0830075B2 (da)
CN (1) CN1018645B (da)
DE (1) DE3712821C2 (da)
DK (1) DK184687A (da)
GB (1) GB2189246B (da)

Families Citing this family (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP2787789B2 (ja) * 1991-10-21 1998-08-20 ファナック株式会社 射出成形機におけるスクリュー連結構造
TW296401B (da) * 1994-12-26 1997-01-21 Shinetsu Chem Ind Co
RU2101290C1 (ru) * 1995-03-31 1998-01-10 Акционерное общество Научно-производственный концерн "Алтай" Способ получения диацетон-l-сорбозы
JP3552825B2 (ja) * 1995-12-15 2004-08-11 矢崎総業株式会社 熱可塑性樹脂とオイルブリード性シリコーンゴムとの一体成形自動車用防水コネクタ
RU2404989C2 (ru) * 2008-08-06 2010-11-27 Учреждение Российской академии наук Институт высокомолекулярных соединений РАН (ИВС РАН) 2,3; 4,5-ди-о-изопропилиден-l-сорбопираноза

Citations (7)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3607862A (en) 1969-02-04 1971-09-21 Hoffmann La Roche Process for preparing carbohydrate ketals
US3622560A (en) 1969-02-04 1971-11-23 Hoffmann La Roche Preparation of ketal sugars
US3723412A (en) 1967-02-13 1973-03-27 Cpc International Inc Preparation of acetone glucose
US4460767A (en) 1981-09-29 1984-07-17 Takeda Chemical Industries, Ltd. Process for production of sugar ketals
US4464530A (en) 1982-03-29 1984-08-07 Takeda Chemical Industries, Ltd. Process for production of sugar ketals
US4659809A (en) 1983-09-27 1987-04-21 Takeda Chemical Industries, Ltd. Process for production of sugar ketals
US4681936A (en) 1985-02-15 1987-07-21 Basf Aktiengesellschaft Preparation of sugar ketals

Family Cites Families (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE2003067A1 (de) * 1969-02-04 1970-08-06 Hoffmann La Roche Verfahren zur Herstellung von Ketalzuckern
JPS6072895A (ja) * 1983-09-28 1985-04-24 Takeda Chem Ind Ltd ２−ケトグロン酸およびそのエステルのケタ−ルの製造法
JPH0629198B2 (ja) * 1984-10-19 1994-04-20 武田薬品工業株式会社 化学的脱水反応方法
JPH0727859B2 (ja) * 1993-04-05 1995-03-29 株式会社東芝 荷電粒子ビーム描画装置

Patent Citations (7)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3723412A (en) 1967-02-13 1973-03-27 Cpc International Inc Preparation of acetone glucose
US3607862A (en) 1969-02-04 1971-09-21 Hoffmann La Roche Process for preparing carbohydrate ketals
US3622560A (en) 1969-02-04 1971-11-23 Hoffmann La Roche Preparation of ketal sugars
US4460767A (en) 1981-09-29 1984-07-17 Takeda Chemical Industries, Ltd. Process for production of sugar ketals
US4464530A (en) 1982-03-29 1984-08-07 Takeda Chemical Industries, Ltd. Process for production of sugar ketals
US4659809A (en) 1983-09-27 1987-04-21 Takeda Chemical Industries, Ltd. Process for production of sugar ketals
US4681936A (en) 1985-02-15 1987-07-21 Basf Aktiengesellschaft Preparation of sugar ketals

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Publication number Publication date
DK184687A (da) 1987-10-18
GB2189246B (en) 1989-11-29
CN1018645B (zh) 1992-10-14
DK184687D0 (da) 1987-04-10
JPS6345292A (ja) 1988-02-26
GB2189246A (en) 1987-10-21
DE3712821C2 (de) 1998-04-09
JPH0830075B2 (ja) 1996-03-27
CN87103553A (zh) 1988-03-09
GB8709089D0 (en) 1987-05-20
DE3712821A1 (de) 1987-10-22

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