CN114621246B - Method for preparing isoidide diacetate - Google Patents

Method for preparing isoidide diacetate Download PDF

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Publication number
CN114621246B
CN114621246B CN202011455257.8A CN202011455257A CN114621246B CN 114621246 B CN114621246 B CN 114621246B CN 202011455257 A CN202011455257 A CN 202011455257A CN 114621246 B CN114621246 B CN 114621246B
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isoidide
diacetate
sugar alcohol
reaction
sorbitol
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CN114621246A (en
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车鹏华
徐杰
高进
马红
苗虹
聂鑫
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Dalian Institute of Chemical Physics of CAS
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Dalian Institute of Chemical Physics of CAS
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    • CCHEMISTRY; METALLURGY
    • C07ORGANIC CHEMISTRY
    • C07DHETEROCYCLIC COMPOUNDS
    • C07D493/00Heterocyclic compounds containing oxygen atoms as the only ring hetero atoms in the condensed system
    • C07D493/02Heterocyclic compounds containing oxygen atoms as the only ring hetero atoms in the condensed system in which the condensed system contains two hetero rings
    • C07D493/04Ortho-condensed systems
    • YGENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y02TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
    • Y02PCLIMATE CHANGE MITIGATION TECHNOLOGIES IN THE PRODUCTION OR PROCESSING OF GOODS
    • Y02P20/00Technologies relating to chemical industry
    • Y02P20/50Improvements relating to the production of bulk chemicals
    • Y02P20/584Recycling of catalysts

Abstract

The application discloses a method for preparing isoidide diacetate. The method for preparing isoidide diacetate comprises the steps of contacting raw materials containing biological base sugar alcohol substances and an acetylation reagent with a solid acid catalyst, and carrying out one-pot reaction to obtain isoidide diacetate; wherein the sugar alcohol substance comprises at least one of sorbitol and isosorbide. The synthesis method has the advantages of easily obtained raw materials, no need of hydrogen and hydrogenation catalyst, mild reaction conditions, simple operation, low requirements on equipment, easy separation of products and recycling of the catalyst.

Description

Method for preparing isoidide diacetate
Technical Field
The application relates to a method for preparing isoidide diacetate, belonging to the technical field of catalytic synthesis.
Background
Isohexides, mainly comprising isosorbide, isomannide and isoidide, are an important class of biobased functional diols, and can be obtained by dehydration of sugar-derived hexides. The isohexide has unique characteristics of dihydroxyl functional groups, rigid structure, chiral centers, no toxicity and the like, can be applied to the fields of green solvents, medicines, surfactants, plasticizers, fuel additives, polymers and the like by self or further chemical modification, and has very wide application prospect. More importantly, the isohexide as a bio-based polymerized monomer has great potential to replace the traditional toxic petroleum-based monomer and is used for constructing polymerized materials such as polyester, polyether, polyurethane, polycarbonate and the like with excellent performances such as high glass transition temperature and the like.
The internal hydroxyl group presents larger steric hindrance than the external hydroxyl group under the influence of the dihydroxyl configuration in the molecular structure of the isohexide, so that the reactivity of the isohexide is lower. Thus, the asymmetry of the two hydroxyl configurations in isosorbide molecules results in their different reactivity and limited polymer crystallinity. Similarly, isomannide molecules have two symmetrical internal hydroxyl groups, but are limited by steric hindrance, resulting in low reactivity and low linearity of the polymerization product, which are detrimental to the polymerization reaction. Compared with the two isohexide, isoidide has two symmetrical outer hydroxyl groups, and the symmetry and high reactivity of the hydroxyl structure of the isoidide make isoidide more suitable for being used as a polymerization monomer, so that a polymerization material with excellent performances such as high crystallinity and the like is constructed.
Although isoidide can be obtained by continuous dehydration of idide as the product of hydrogenation of glucose by secondary dehydration of sorbitol, idide is rarely found in nature and cannot be obtained in large quantities from plant sources, so the route of obtaining idide by catalytic hydrogenation of idide followed by continuous dehydration to isoidide is not suitable for large-scale production. The literature reports that iditol can be obtained by catalytic isomerization of sorbitol under high temperature and high pressure hydrogen conditions by a nickel catalyst, but the separation difficulty of iditol is great because of the high boiling point and strong polarity hexahydric alcohol isomer mixture obtained. In summary, in view of the difficulty in obtaining idide and idide materials, the synthetic route for preparing idide by idide catalytic dehydration is not suitable for large-scale production of idide.
The synthesis of isoidide by epimerization from readily available isosorbide as a starting material is of interest given the relatively difficult availability of the starting material idide. The current literature relates to the isomerization of isosorbide to isoidide, which requires hydrogen and a hydrogenation catalyst. For example, the literature reports that under the severe conditions of high temperature of 220-240 ℃ and high hydrogen pressure of 10.3MPa, the kieselguhr supported metal Ni is used as a catalyst to catalyze the isomerization of isosorbide, the reaction is carried out for 2 hours to reach equilibrium, and the yield of the obtained isoidide is 57%. As another example, it has been reported that using Ru/C catalyst, isosorbide can be catalyzed to epimerization in an alkaline aqueous solution (ph=8) at 220 ℃ and 4MPa hydrogen to yield isoidide at 55%. However, high temperature, high pressure hydrogen and hydrogenation catalyst are necessary for isomerization of isosorbide to isoidide, and the resulting isohexide isomer mixture requires high energy consumption distillation at high temperature and high vacuum to purify isoidide, which is prone to carbonize isohexide, affecting the yield and quality of the product.
The high boiling point of isoidide is derived from strong polar and intermolecular hydrogen bonds caused by dihydroxyl groups, so that after the two free hydroxyl groups are modified by acetylation to form isoidide diacetate, the boiling point of isoidide diacetate is obviously reduced, and the energy consumption for separation is reduced. Furthermore, the dihydroxyl functional group is a main cause of high-temperature carbonization of isoidide, and is expected to inhibit polymerization side reaction after esterification modification. In addition, the esterification reaction is a reversible reaction, and isoidide diacetate is readily hydrolyzed or alcoholyzed to form isoidide. Based on the method, the isoidide diacetate is used for replacing isoidide as a target product, and has remarkable advantages in separation and purification. At present, the research on directly preparing isoidide diacetate from easily available sorbitol or isosorbide has not been reported yet.
In conclusion, the existing isoidide preparation technology by isomerisation of isosorbide has the problems of harsh reaction conditions (high temperature and high pressure), high requirements on equipment by using hydrogen and a hydrogenation catalyst, high energy consumption for isoidide separation, easiness in carbonization of substrates in the high-temperature distillation process and the like.
Disclosure of Invention
Aiming at the problems of high temperature, high pressure and harsh reaction conditions existing in the existing isoidide preparation technology, high Wen Gaozhen empty high energy consumption separation operation and easy carbonization in the separation process, the application provides a novel method for preparing isoidide diacetate by using a solid acid catalytic sorbitol or isosorbide one-pot method. The method has the advantages of easily obtained raw materials, no need of hydrogen and hydrogenation catalyst, mild reaction conditions, simple operation, low equipment requirements, easily separated products, recoverable catalyst, and the like.
According to one aspect of the present application, a process for preparing isoidide diacetate is provided.
A method for preparing isoidide diacetate comprises the steps of contacting raw materials containing biological base sugar alcohol substances and an acetylating reagent with a solid acid catalyst, and carrying out one-pot reaction to obtain isoidide diacetate;
wherein the sugar alcohol substance comprises at least one of sorbitol and isosorbide.
Optionally, the solid acid catalyst comprises at least one of strong acid cation exchange resin, hydrogen zeolite molecular sieve, keggin type heteropolyacid and solid super acid.
Optionally, the strong acid cation exchange resin is selected from at least one of Amberlyst-15, amberlyst-35, amberlyst-70, nafion-H.
Optionally, the hydrogen form zeolite molecular sieve is selected from at least one of H-ZSM-5, H-Beta and H-Y.
Optionally, the Keggin type heteropoly acid is selected from at least one of phosphotungstic heteropoly acid and silicotungstic heteropoly acid.
Optionally, the solid super acid is selected from at least one of sulfated zirconia and sulfated alumina.
Optionally, the acetylating agent is at least one selected from acetic acid, acetic anhydride and acetyl chloride.
Optionally, an aprotic solvent is also added to the feedstock.
Optionally, the aprotic solvent is selected from at least one of sulfolane, ethyl acetate, butyl acetate, cyclohexane and toluene.
Optionally, the mass ratio of the solid acid catalyst to the bio-based sugar alcohol is 0.005:1-1:1.
Preferably, the mass ratio of the solid acid catalyst to the bio-based sugar alcohol is 0.01:1-0.7:1.
Optionally, the mass ratio of the solid acid catalyst to the biobased sugar alcohol is independently selected from any value or range of values between any two of 0.005:1, 0.01:1, 0.03:1, 0.05:1, 0.07:1, 0.1:1, 0.2:1, 0.3:1, 0.4:1, 0.5:1, 0.6:1, 0.7:1.
Optionally, the molar ratio of the acetylation reagent to the biological sugar alcohol substance is 2:1-150:1.
Preferably, the molar ratio of the acetylation reagent to the biological sugar alcohol substance is 4:1-100:1.
Optionally, the molar ratio of the acetylating reagent to the biobased sugar alcohol is independently selected from any value or range of values between any two of 2:1, 4:1, 7:1, 10:1, 20:1, 40:1, 50:1, 70:1, 90:1, 100:1, 120:1, 140:1, 150:1.
Optionally, the molar ratio of the aprotic solvent to the bio-based sugar alcohol is 0-100:1.
Preferably, the molar ratio of the aprotic solvent to the bio-based sugar alcohol is 0-70:1.
Optionally, the molar ratio of aprotic solvent to biobased sugar alcohol is independently selected from any value or range between any two of 1:1, 5:1, 8:1, 10:1, 15:1, 20:1, 30:1, 40:1, 50:1, 60:1, 70:1, 80:1, 90:1, 100:1.
In the present application, the aprotic solvent is optionally added.
Optionally, the temperature of the reaction is 130-200 ℃; the reaction time is 0.5-12 h.
Preferably, the temperature of the reaction is 150-200 ℃ and the reaction time is 1-10 h.
Alternatively, the temperature of the reaction is independently selected from any value or range of values between any two of 130 ℃, 140 ℃, 150 ℃, 160 ℃,170 ℃,180 ℃,190 ℃,200 ℃.
Alternatively, the time of the reaction is independently selected from any value or range of values between any two of 0.5h, 1h, 2h, 4h, 5h, 6h, 8h, 10h, 12h.
The pressure of the reaction is not particularly limited, and the reaction may be carried out under sealed self-pressurizing conditions.
In view of the advantages that the boiling point and carbonization activity of isoidide diacetate are obviously lower than those of isoidide, the application explores a new strategy, realizes the one-pot preparation of the isoidide diacetate by sorbitol or isosorbide under mild conditions, avoids the use of hydrogen and hydrogenation catalysts, and has important significance.
The application has the beneficial effects that:
the method for preparing the isoidide diacetate provided by the application is an environment-friendly novel synthesis strategy for preparing the isoidide diacetate by directly taking sugar alcohol substances (such as sorbitol and isosorbide) as raw materials in one pot, and has the advantages of taking widely-available bio-based sorbitol or isosorbide as raw materials, and obtaining the isoidide diacetate by an environment-friendly solid acid catalytic conversion method in one pot. The method does not need hydrogen and hydrogenation catalyst, has mild reaction conditions, simple operation and low requirements on equipment; the isoidide is a target product, so that the energy consumption can be effectively reduced, and the isoidide is not easy to carbonize; the solid acid catalyst can be recovered and reused.
Detailed Description
The present application is described in detail below with reference to examples, but the present application is not limited to these examples.
The starting materials and catalysts in the examples of the present application were purchased commercially, unless otherwise specified. If not specified, the test methods are all conventional methods, and the instrument settings are all recommended by manufacturers.
Isoidide diacetate yield in the examples of the application was calculated as molar yield:
yield of isoidide diacetate = mol% isoidide diacetate formation/mol% sorbitol or isosorbide dosed x 100%
Example 1
Sorbitol, acetic acid and a solid acid catalyst H-ZSM-5 molecular sieve (SiO 2 /Al 2 O 3 =150) was placed in a reaction vessel, nitrogen was replaced, the reactor was closed, and the reaction was magnetically stirred at 180 ℃ for 5h. Wherein, the mol ratio of acetic acid to sorbitol is 70:1, and the mass ratio of H-ZSM-5 to sorbitol is 0.3:1. After the reaction is finished, the esterification product is quantitatively analyzed by adopting a gas chromatography internal standard method, and the yield of the obtained isoidide diacetate is 45mol percent in terms of mole percent (mol percent).
Example 2
Sorbitol, acetic anhydride, ethyl acetate and a solid acid catalyst Amberlyst-15 are put into a reaction kettle, nitrogen is replaced, the reactor is closed, and the reaction is carried out for 10 hours by magnetic stirring at 130 ℃. Wherein, the mol ratio of acetic anhydride to sorbitol is 10:1, the mol ratio of ethyl acetate to sorbitol is 10:1, and the mass ratio of amberlyst-15 to sorbitol is 0.7:1. After the reaction is finished, the esterification product is quantitatively analyzed by adopting a gas chromatography internal standard method, and the yield of the obtained isoidide diacetate is 42mol percent in terms of mole percent (mol percent).
Example 3
Sorbitol, acetic acid, toluene and a solid acid catalyst H-Beta molecular sieve (SiO 2 /Al 2 O 3 =100) was placed in a reaction vessel, nitrogen was replaced, the reactor was closed, and the reaction was magnetically stirred at 190 ℃ for 4h. Wherein, the mol ratio of acetic acid to sorbitol is 90:1, the mol ratio of toluene to sorbitol is 30:1, and the mass ratio of H-Beta to sorbitol is 0.2:1. After the reaction is finished, the esterification product is quantitatively analyzed by adopting a gas chromatography internal standard method, and the yield of the obtained isoidide diacetate is 47mol percent in terms of mole percent (mol percent).
Example 4
Sorbitol, acetic acid and solid acid catalyst phosphotungstic acid are put into a reaction kettle, nitrogen is replaced, the reactor is closed, and the reaction is carried out for 2 hours by magnetic stirring at 200 ℃. Wherein the molar ratio of acetic acid to sorbitol is 4:1, and the mass ratio of phosphotungstic heteropolyacid to sorbitol is 0.1:1. After the reaction is finished, the esterification product is quantitatively analyzed by adopting a gas chromatography internal standard method, and the yield of the obtained isoidide diacetate is 41mol percent in terms of mole percent (mol percent).
Example 5
Isosorbide, acetic acid, butyl acetate and a solid acid catalyst Nafion-H are put into a reaction kettle, nitrogen is replaced, the reactor is closed, and the reaction is carried out for 2 hours by magnetic stirring at 200 ℃. Wherein, the mol ratio of acetic acid to isosorbide is 40:1, the mol ratio of butyl acetate to isosorbide is 50:1, and the mass ratio of Nafion-H to isosorbide is 0.05:1. After the reaction is finished, the esterification product is quantitatively analyzed by adopting a gas chromatography internal standard method, and the yield of the obtained isoidide diacetate is 48mol percent in terms of mole percent (mol percent).
Example 6
Sorbitol, acetic acid, sulfolane and solid acid catalyst sulfated zirconia are put into a reaction kettle, nitrogen is replaced, the reactor is closed, and the reaction is carried out for 2 hours by magnetic stirring at 200 ℃. Wherein the molar ratio of acetic acid to sorbitol is 120:1, the molar ratio of sulfolane to sorbitol is 70:1, and the mass ratio of sulfated zirconia to sorbitol is 0.4:1. After the reaction is finished, the esterification product is quantitatively analyzed by adopting a gas chromatography internal standard method, and the yield of the obtained isoidide diacetate is 46mol percent in terms of mole percent (mol percent).
Example 7
Isosorbide, acetic acid, cyclohexane and solid acid catalyst silicon tungsten heteropoly acid are put into a reaction kettle, nitrogen is replaced, the reactor is closed, and magnetic stirring is carried out at 170 ℃ for 4 hours. Wherein, the mol ratio of acetic acid to isosorbide is 20:1, the mol ratio of cyclohexane to isosorbide is 5:1, and the mass ratio of silicotungstic acid to isosorbide is 0.4:1. After the reaction is finished, the esterification product is quantitatively analyzed by adopting a gas chromatography internal standard method, and the yield of the obtained isoidide diacetate is 47mol percent in terms of mole percent (mol percent).
While the application has been described in terms of preferred embodiments, it will be understood by those skilled in the art that various changes and modifications can be made without departing from the scope of the application, and it is intended that the application is not limited to the specific embodiments disclosed.

Claims (5)

1. A method for preparing isoidide diacetate is characterized in that raw materials containing biological glycosyl alcohol substances and an acetylating reagent are contacted with a solid acid catalyst and reacted in a one-pot way to obtain isoidide diacetate;
wherein the biological sugar alcohol is at least one of sorbitol and isosorbide;
the solid acid catalyst is at least one selected from strong acid cation exchange resin, hydrogen type zeolite molecular sieve, keggin type heteropolyacid and solid super acid;
the strong acid cation exchange resin is selected from at least one of Amberlyst-15, amberlyst-35, amberlyst-70 and Nafion-H;
the hydrogen type zeolite molecular sieve is selected from at least one of H-ZSM-5, H-Beta and H-Y;
the Keggin type heteropolyacid is selected from at least one of phosphotungstic heteropolyacid and silicotungstic heteropolyacid;
the solid super acid is at least one selected from sulfated zirconia and sulfated alumina;
the acetylating agent is at least one of acetic acid, acetic anhydride and acetyl chloride;
adding an aprotic solvent to the feedstock;
the aprotic solvent is selected from at least one of sulfolane, ethyl acetate, butyl acetate, cyclohexane and toluene;
the mass ratio of the solid acid catalyst to the bio-based sugar alcohol substance is 0.01:1-0.7:1;
the mol ratio of the acetylation reagent to the biological glycosyl sugar alcohol substance is 2:1-150:1;
the reaction temperature is 130-200 ℃; the reaction time is 0.5-12 h.
2. The method of claim 1, wherein the molar ratio of the acetylating agent to the biosyl sugar alcohol is 4:1 to 100:1.
3. The method of claim 1, wherein the molar ratio of the aprotic solvent to the biobased sugar alcohol is 0-100:1.
4. The method of claim 1, wherein the molar ratio of the aprotic solvent to the biobased sugar alcohol is 0-70:1.
5. The method according to claim 1, wherein the reaction temperature is 150-200 ℃ and the reaction time is 1-10 hours.
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CN107722030A (en) * 2016-08-10 2018-02-23 中国科学院大连化学物理研究所 A kind of method for preparing dissident's sugar alcohol
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