2, 3, 4, 6-tetra-O-trimethylsilyl-D-glucolactone and preparation method thereof

Abstract

The invention discloses 2, 3, 4, 6-tetra-O-trimethylsilyl-D-glucolactone and a preparation method thereof.The preparation method comprises the steps that S100, raw materials including glucolactone and hexamethyldisilazane are adopted, iodine serves as a catalyst, and a reaction is conducted to obtain a first material; s200, carrying out adsorption treatment on the first material by adopting activated carbon; and S300, carrying out purification treatment on the first material subjected to the adsorption treatment, so as to obtain the 2, 3, 4, 6-tetra-O-trimethylsilyl-D-glucolactone. According to the method, the influence of the catalyst iodine on the color of the product can be thoroughly removed in an activated carbon adsorption mode, and the high-quality finished 2, 3, 4, 6-tetra-O-trimethylsilyl-D-glucolactone product can be obtained.

Description

Technical Field

[0001] The invention relates to the field of chemical materials, in particular to the preparation of 2,3,4,6-tetra-O-trimethylsilyl-D-gluconolactone. Background Art

[0002] 2,3,4,6-Tetrakis-O-trimethylsilyl-D-gluconolactone is a kind of sugar derivative. In its chemical structure, the hydroxyl groups (OH) at the 2, 3, 4, and 6 positions of gluconolactone are replaced by trimethylsilyl (TMS). This substitution reaction is usually to protect the hydroxyl group to prevent it from undergoing unnecessary reactions in subsequent chemical reactions, or to change the physical and chemical properties of the molecule to meet specific application requirements.

[0003] 2,3,4,6-Tetra-O-trimethylsilyl-D-gluconolactone is widely used in the pharmaceutical, pesticide, dye, and fragrance industries. In the pharmaceutical field, it is often used as an important intermediate for the synthesis of certain drugs. Due to the introduction of trimethylsilyl, the compound is more stable under certain reaction conditions, which is conducive to the construction and modification of drug molecules. In addition, 2,3,4,6-Tetra-O-trimethylsilyl-D-gluconolactone also has certain biological activity and may have certain pharmacological effects, so it is also used in biological and medical research. 2,3,4,6-Tetra-O-trimethylsilyl-D-gluconolactone can be used as an intermediate for the therapeutic raw material dapagliflozin / dapagliflozin for adult patients with type 2 diabetes, and is also used in the synthesis of the glucose side chain of canagliflozin / canagliflozin. In addition, it can also be used in the fields of cell culture scientific research reagents.

[0004] 2,3,4,6-tetra-O-trimethylsilyl-D-gluconolactone can be synthesized by introducing a trimethylsilyl (TMS) protecting group into gluconolactone. Commonly used methods for adding a TMS protecting group include using reagents such as trimethylchlorosilane or trimethylsilyl imidazole. At present, the method for preparing 2,3,4,6-tetra-O-trimethylsilyl-D-gluconolactone using a continuous flow microchannel reactor has been studied and applied.

[0005] The patent application with publication number WO2016142950A1 discloses a method for preparing 2,3,4,6-tetra-O-triylsilyl-D-gluconolactone, which uses gluconolactone as the starting material, and in a 4-methylmorpholine (NMM) and tetrahydrofuran (THF) system, trimethylsilyl chloride (TMSCl) is added dropwise into the reaction system at -5 to 0°C. After the addition is completed, the reaction is carried out at 25 to 30°C for 18 to 20 hours. After the reaction is completed, toluene / n-heptane is used as an extractant, and the mixture is washed with water, washed with sodium bicarbonate aqueous solution or adjusted to pH 7 to 8, and washed with saturated brine. The organic phase is extracted with the extractant, and the organic phase is concentrated and combined to obtain an oily product.

[0006] The patent application with publication number CN106632288A discloses a method for preparing 2,3,4,6-tetra-O-trimethylsilyl-D-gluconolactone, which comprises adding gluconolactone, n-methylmorpholine and THF into a reaction kettle, stirring the reaction kettle, controlling the temperature at -5 to 0°C under an inert atmosphere, dripping trimethylchlorosilane, raising the temperature to 20-25°C, and stirring the reaction for 15-20 hours to prepare the product. Specifically, the above-mentioned preparation reaction is carried out in an inert atmosphere to avoid oxidation of the product; in addition, since the exotherm is relatively intense when the trimethylchlorosilane and the n-methylmorpholine react to form a complex, the trimethylchlorosilane needs to be dripped at a temperature of -5 to 0°C to avoid an overly intense reaction.

[0007] The patent application with publication number CN102574829A discloses that when preparing 2,3,4,6-tetra-O-trimethylsilyl-D-gluconolactone, 130.8 kg of trimethylchlorosilane is added at 13-19 ° C within 50 minutes to treat a suspension of 42.0 kg of gluconolactone, 277.2 kg of tetrahydrofuran, 4-methylmorpholine (152.4 kg) and 4-lutidine (1.44 kg). After the addition is completed, stirring is continued at 20-22 ° C for 1.5 hours, and then 216.4 kg of n-heptane is added and the mixture is cooled to 5 ° C. 143 kg of water is added at 3-5 ° C within 15 minutes, stirred, separated, distilled, and 130 kg of n-heptane is added to the residue, filtered, washed, and distilled to obtain an oily product containing residual n-heptane. This method requires that the trimethylchlorosilane be added dropwise within 50 minutes. Since the addition process generates severe heat, this presents a potential safety hazard in large-scale industrial production and is not suitable for large-scale industrial production.

[0008] Patent application with publication number CN102656177A discloses that trimethylsilyl chloride (29.1 kg, 267.9 mol) is added to a solution of gluconolactone (7.88 kg, 44.23 mol) and n-methylmorpholine (3.58 kg, 353.9 mol) in tetrahydrofuran (70 kg) at a temperature below 40°C, and the resulting mixture is stirred at 30-40°C for 2 hours. The reaction mixture is cooled to 0°C, toluene (34 kg) and water (39 kg) are added, the organic layer is separated, the organic layer is washed twice with a 5% sodium dihydrogen phosphate aqueous solution (39.56 kg), washed once with water (39 kg), and the target product is obtained by distillation under reduced pressure.

[0009] The patent application with publication number CN113372379A discloses that the target product is prepared in a continuous flow microchannel reactor using gluconolactone and hexamethyldisilazane as main raw materials and iodine as catalyst. The reaction solution is diluted with chloroform and then added to an acetic acid aqueous solution for quenching. The organic phase after stratification is washed with a sodium dihydrogen phosphate aqueous solution and then purified by distillation to obtain the product.

[0010] By analyzing the above prior art, it is known that 2,3,4,6-tetra-O-trimethylsilyl-D-gluconolactone can be prepared by reacting with trimethylchlorosilane (TMSCl) as the starting material under different conditions. It has strict requirements on the cooling efficiency of production equipment for the feeding method, which limits the industrialized large-scale production of the product and easily causes unstable production of product quality. Therefore, a kind of safety is good, easy to operate and controllable, and the requirements for site equipment are not strict, and the preparation method of 2,3,4,6-tetra-O-trimethylsilyl-D-gluconolactone for large-scale production is needed in the prior art. In addition, for the technical scheme of preparing 2,3,4,6-tetra-O-trimethylsilyl-D-gluconolactone in a continuous flow microchannel reactor with gluconolactone, hexamethyldisilazane as the main raw material and iodine as the catalyst, it is after post-treatment, and the catalyst iodine in the material cannot be completely removed, and the residual iodine makes the product appear purple, which is also a technical problem that those skilled in the art need to solve. Summary of the invention

[0011] The purpose of the present application is to provide a 2,3,4,6-tetra-O-trimethylsilyl-D-gluconolactone and a preparation method thereof, which can solve the technical problems in the prior art that the production process of 2,3,4,6-tetra-O-trimethylsilyl-D-gluconolactone is not safe and controllable, the operation is complicated, and it is not suitable for large-scale production.

[0012] In order to solve the above technical problems, this application is implemented as follows:

[0013] The present application provides a method for preparing 2,3,4,6-tetra-O-trimethylsilyl-D-gluconolactone, the method comprising:

[0014] S100, using raw materials including gluconolactone and hexamethyldisilazane and iodine as a catalyst to react and prepare a first material;

[0015] S200, using activated carbon to perform adsorption treatment on the first material;

[0016] S300, purifying the first material after the adsorption treatment to obtain the 2,3,4,6-tetra-O-trimethylsilyl-D-gluconolactone.

[0017] In the above technical solution, S100 specifically includes:

[0018] S110, under an inert gas protective atmosphere, feeding the solvent, the gluconolactone and the catalyst into a first reaction kettle, stirring and cooling to a first reaction temperature;

[0019] S120, controlling the first reaction kettle not to exceed a second reaction temperature, and dropwise adding the hexamethyldisilazane into the first reaction kettle;

[0020] S130, after the hexamethyldisilazane is added dropwise, the temperature is raised to a third reaction temperature and kept warm for reaction to obtain the first material.

[0021] In the above technical solution, in S110 and S120, for every 100 kg of the gluconolactone added, 0.4 kg to 0.6 kg of the catalyst is added accordingly, and 190 kg to 210 kg of the hexamethyldisilazane is added dropwise accordingly.

[0022] In the above technical solution, in S110 and S120, for every 100 kg of the gluconolactone added, 0.5 kg of the catalyst is added accordingly, and 199.3 kg of the hexamethyldisilazane is added dropwise accordingly.

[0023] In the above technical solution, in S110, for every 100 kg of the gluconolactone added, 600 L to 1000 L of the solvent is added accordingly.

[0024] In the above technical scheme, in S110, the first reaction temperature is 5°C to 10°C; in S120, the second reaction temperature does not exceed 15°C; in S130, the third reaction temperature is 25°C to 30°C; in S120, the hexamethyldisilazane is controlled to be added within 2 hours.

[0025] In the above technical solution, S200 specifically includes:

[0026] S210, transferring the first material to a second reactor and cooling the reactor to an adsorption temperature;

[0027] S220, adding the activated carbon into the second reactor, and stirring at the adsorption temperature for 2 hours to 4 hours to perform the adsorption treatment.

[0028] In the above technical solution, the adsorption temperature is 20° C.; for every 100 kg of the gluconolactone added in S110 , 20 kg of the solvent activated carbon is added in S220 accordingly.

[0029] In the above technical solution, S300 specifically includes:

[0030] S310, performing filter press on the first material subjected to the adsorption treatment to obtain a filtrate;

[0031] S320, adding N-methylmorpholine to the filtrate and stirring, adding a mixed aqueous solution of sodium thiosulfate and sodium chloride and continuing to stir, letting stand and then separating, and extracting the first lower organic layer;

[0032] S330, adding a mixed aqueous solution of sodium thiosulfate and sodium chloride to the first lower organic layer and stirring, allowing to stand and then separating, and extracting a second lower organic layer;

[0033] S340, adding sodium chloride solution to the second lower organic layer with stirring, allowing to stand and then separating the liquids and removing the solvent by distillation to obtain the crude product of 2,3,4,6-tetra-O-trimethylsilyl-D-gluconolactone;

[0034] S350, sending the crude product of the 2,3,4,6-tetra-O-trimethylsilyl-D-glucono-lactone into a distillation tower for distillation to obtain the finished product of the 2,3,4,6-tetra-O-trimethylsilyl-D-glucono-lactone.

[0035] The present invention also provides 2,3,4,6-tetra-O-trimethylsilyl-D-gluconolactone, and the 2,3,4,6-tetra-O-trimethylsilyl-D-gluconolactone is obtained by the preparation method described in any of the above technical solutions.

[0036] Beneficial Effects

[0037] The present invention provides a method for preparing 2,3,4,6-tetra-O-trimethylsilyl-D-gluconolactone, wherein the preparation method first adopts raw materials including gluconolactone and hexamethyldisilazane, takes iodine as a catalyst, and reacts to prepare a first material; then uses activated carbon to adsorb the first material; finally, purifies the first material after the adsorption treatment to obtain the 2,3,4,6-tetra-O-trimethylsilyl-D-gluconolactone. The technical solution adopted by the present invention has good safety, convenient and controllable operation, is not demanding on site equipment, has high yield, and is easy to realize the preparation method of 2,3,4,6-tetra-O-trimethylsilyl-D-gluconolactone for large-scale production. In addition, the present invention completely removes the catalyst iodine in the material through activated carbon adsorption, avoids the residual iodine from making the product appear purple, thereby improving the product quality. BRIEF DESCRIPTION OF THE DRAWINGS

[0038] Figure 1 The present invention is a process flow chart of the preparation method of 2,3,4,6-tetra-O-trimethylsilyl-D-gluconolactone according to an embodiment of the present invention. DETAILED DESCRIPTION

[0039] In order to make the above-mentioned objects, features and advantages of the present invention more obvious and easy to understand, the following is a detailed description of the specific embodiments of the present invention.

[0040] Unless otherwise specified, the reagents and raw materials used in the present invention can be purchased through commercial channels. The experimental methods in the following examples without specifying specific conditions are selected according to conventional methods and conditions, or according to the product specifications.

[0041] The present invention provides a method for preparing 2,3,4,6-tetra-O-trimethylsilyl-D-gluconolactone, the preparation method comprising:

[0042] S100, using raw materials including gluconolactone and hexamethyldisilazane and iodine as a catalyst to react and prepare a first material;

[0043] S200, using activated carbon to perform adsorption treatment on the first material;

[0044] S300, purifying the first material after the adsorption treatment to obtain the 2,3,4,6-tetra-O-trimethylsilyl-D-gluconolactone.

[0045] In the above steps, gluconolactone (GDL) is also called gluconolactone or gluconolactone. Hexamethyldisilane is also called hexamethyldisilane. The gluconolactone and hexamethyldisilane of the present invention can be purchased through commercial channels.

[0046] It should be noted that in the present invention, iodine is used as a catalyst, and 2,3,4,6-tetra-O-trimethylsilyl-D-gluconolactone is prepared by the reaction of gluconolactone and hexamethyldisilazane. Since the catalyst iodine in the material is difficult to completely remove, the residual iodine makes the product appear purple, so the present invention uses activated carbon to adsorb the first material. After the adsorption treatment, further purification treatment is required to obtain high-quality 2,3,4,6-tetra-O-trimethylsilyl-D-gluconolactone.

[0047] In some implementations of the present invention, S100 specifically includes:

[0048] S110, under an inert gas protective atmosphere, feeding the solvent, the gluconolactone and the catalyst into a first reaction kettle, stirring and cooling to a first reaction temperature;

[0049] S120, controlling the first reaction kettle not to exceed a second reaction temperature, and dropwise adding the hexamethyldisilazane into the first reaction kettle;

[0050] S130, after the hexamethyldisilazane is added dropwise, the temperature is raised to a third reaction temperature and kept warm for reaction to obtain the first material.

[0051] In the above embodiments, the inert gas may be helium (He), neon (Ne), argon (Ar), krypton (Kr), xenon (Xe), radon (Rn, radioactive), etc. Preferably, the present invention uses nitrogen as the inert gas. In an inert gas protective atmosphere, decomposition of raw materials or reactants can be effectively avoided.

[0052] It is understood that the reaction temperature has an important influence on the quality and efficiency of the reaction of the present invention. Preferably, in S110, the first reaction temperature is 5°C to 10°C; in S120, the second reaction temperature does not exceed 15°C; in S130, the third reaction temperature is 25°C to 30°C.

[0053] It is understood that the rate of adding the hexamethyldisilazane dropwise will have an important impact on the quality and efficiency of the reaction of the present invention. The present invention needs to control the hexamethyldisilazane to be added dropwise within 2 hours.

[0054] It should be noted that after the hexamethyldisilazane is added dropwise, the heat preservation reaction should be continued, and after the heat preservation reaction is completed, the first material can be obtained. Preferably, in S130, the heat preservation reaction is continued for 3 hours.

[0055] It is understood that the addition amount and ratio of each raw material will also have an important impact on the quality and efficiency of the reaction of the present invention. Preferably, in S110 and S120, for every 100kg of the gluconolactone, 0.4kg to 0.6kg of the catalyst is correspondingly put into, and 190kg to 210kg of the hexamethyldisilazane is added dropwise. Further preferably, in S110 and S120, for every 100kg of the gluconolactone, 0.5kg of the catalyst is correspondingly put into, and 199.3kg of the hexamethyldisilazane is added dropwise. In addition, in some embodiments of the present invention, in S110, for every 100kg of the gluconolactone, 600L to 1000L of the solvent is correspondingly put into. Preferably, in S110, for every 100kg of the gluconolactone, 800L of the solvent is correspondingly put into. After the reaction is completed, the first material needs to be further subjected to adsorption, filter pressing and distillation treatment. In some embodiments of the present invention, S200 specifically includes:

[0056] S210, transferring the first material to a second reactor and cooling the reactor to an adsorption temperature;

[0057] S220, adding the activated carbon into the second reactor, and stirring at the adsorption temperature for 2 hours to 4 hours to perform the adsorption treatment.

[0058] In some embodiments of the present invention, the adsorption temperature is 20° C. For every 100 kg of the gluconolactone added in S110 , 20 kg of the solvent activated carbon is added in S220 . Preferably, stirring is performed at the adsorption temperature for 3 hours.

[0059] Finally, in some implementation modes of the present invention, S300 specifically includes:

[0060] S310, performing filter press on the first material subjected to the adsorption treatment to obtain a filtrate;

[0061] S320, adding N-methylmorpholine to the filtrate and stirring, adding a mixed aqueous solution of sodium thiosulfate and sodium chloride and continuing to stir, letting stand and then separating, and extracting the first lower organic layer;

[0062] S330, adding a mixed aqueous solution of sodium thiosulfate and sodium chloride to the first lower organic layer and stirring, allowing to stand and then separating, and extracting a second lower organic layer;

[0063] S340, adding sodium chloride solution to the second lower organic layer with stirring, allowing to stand and then separating the liquids and removing the solvent by distillation to obtain the crude product of 2,3,4,6-tetra-O-trimethylsilyl-D-gluconolactone;

[0064] S350, sending the crude product of the 2,3,4,6-tetra-O-trimethylsilyl-D-glucono-lactone into a distillation tower for distillation to obtain the finished product of the 2,3,4,6-tetra-O-trimethylsilyl-D-glucono-lactone.

[0065] Among them, N-methylmorpholine is an excellent solvent that can dissolve a variety of organic compounds. When washing the filtrate, it can effectively dissolve and take away certain impurities or unreacted substances in the filtrate, thereby playing a role in purifying and purifying the filtrate. Sodium thiosulfate (commonly known as baking soda) has strong complexing ability and reducibility, and can react with certain impurities (such as heavy metal ions, oxidants, etc.) in the filtrate to form water-insoluble precipitates, thereby removing these impurities from the filtrate. Sodium chloride (salt) can be used to remove residues in the filtrate, such as unreacted reagents, excess reactants, etc. By washing, these residues can be separated from the filtrate, thereby improving the purity of the filtrate.

[0066] Example 1

[0067] Figure 1 FIG. 2 is a process flow chart of the preparation method of 2,3,4,6-tetra-O-trimethylsilyl-D-gluconolactone according to an embodiment of the present invention. Figure 1 As shown, this embodiment provides an industrial production method of 2,3,4,6-tetra-O-trimethylsilyl-D-gluconolactone, which comprises the following steps:

[0068] 1. Ensure that the synthesis reactor R1 and the hexamethyldisilazane dropping tank are clean and dry, and the nitrogen is fully replaced at room temperature;

[0069] 2. Add 800L of dichloromethane to the reactor R1, start stirring, add 100kg of gluconolactone and 0.5kg of iodine, and under nitrogen protection, stir and cool the reactor to 5°C to 10°C. Add 199.3kg of hexamethyldisilazane to the dropping tank. When the temperature of the reactor reaches 15°C, start dropping. The dropping temperature should not exceed 15°C, and the dropping time should be about 2 hours.

[0070] 3. After the addition is completed, slowly raise the temperature, keep the reaction at 25°C to 30°C for 3 hours, and take samples for testing;

[0071] 4. Transfer the reaction solution to reactor R2, cool it to 20°C, add 20 kg of activated carbon, stir at 20°C for 3 hours, and filter it into reactor R3;

[0072] 5. Add 0.395 kg of N-methylmorpholine to the filtrate of reactor R3, stir for 15 min, add 100 L of a mixed aqueous solution of 2.5 kg of sodium thiosulfate and 2.5 kg of sodium chloride, stir for 10 min, let stand for 20 min and separate the layers. The lower organic layer is transferred to reactor R4;

[0073] 6. Add 100 L of a mixed aqueous solution of 2.5 kg of sodium thiosulfate and 2.5 kg of sodium chloride to reactor R4 and stir for 10 min. Let stand for 20 min and separate the layers. The lower organic layer is transferred to reactor R5.

[0074] 7. Add 18kg of sodium chloride solution (100L) to reactor R5 and stir for 10min. Let stand for 30min and separate the solution into reactor R6. Ensure that the moisture content of the material is less than 0.4%;

[0075] 8. The solvent is removed by distillation in the reaction kettle R6 to obtain a crude product of 2,3,4,6-tetra-O-trimethylsilyl-D-glucono-lactone, and the crude product of 2,3,4,6-tetra-O-trimethylsilyl-D-glucono-lactone is sent to a distillation tower for distillation to obtain a finished product of 2,3,4,6-tetra-O-trimethylsilyl-D-glucono-lactone.

[0076] Although the present invention is disclosed as above, the present invention is not limited thereto. Any person skilled in the art can make various changes and modifications without departing from the spirit and scope of the present invention. Therefore, the protection scope of the present invention shall be subject to the scope defined by the claims.

Claims

1. A method for preparing 2,3,4,6-tetra-O-trimethylsilyl-D-gluconolactone, characterized in that: The preparation method comprises: S100, using raw materials including gluconolactone and hexamethyldisilazane and iodine as a catalyst to react and prepare a first material; S200, using activated carbon to perform adsorption treatment on the first material; S300, purifying the first material after the adsorption treatment to obtain the 2,3,4,6-tetra-O-trimethylsilyl-D-gluconolactone.

2. The preparation method according to claim 1, characterized in that: S100 specifically includes: S110, under an inert gas protective atmosphere, feeding the solvent, the gluconolactone and the catalyst into a first reaction kettle, stirring and cooling to a first reaction temperature; S120, controlling the first reaction kettle not to exceed a second reaction temperature, and dropwise adding the hexamethyldisilazane into the first reaction kettle; S130, after the hexamethyldisilazane is added dropwise, the temperature is raised to a third reaction temperature and kept warm for reaction to obtain the first material.

3. The preparation method according to claim 2, characterized in that: In S110 and S120, for every 100 kg of the gluconolactone added, 0.4 kg to 0.6 kg of the catalyst is added accordingly, and 190 kg to 210 kg of the hexamethyldisilazane is added dropwise accordingly.

4. The preparation method according to claim 2, characterized in that: In S110 and S120, for every 100 kg of the gluconolactone added, 0.5 kg of the catalyst was added accordingly, and 199.3 kg of the hexamethyldisilazane was added dropwise accordingly.

5. The preparation method according to claim 2, characterized in that: In S110 , for every 100 kg of the gluconolactone added, 600 L to 1000 L of the solvent is added accordingly.

6. The preparation method according to claim 2, characterized in that: In S110, the first reaction temperature is 5°C to 10°C; In S120, the second reaction temperature does not exceed 15°C; In S130, the third reaction temperature is 25°C to 30°C; In S120, the hexamethyldisilazane is controlled to be added dropwise within 2 hours.

7. The preparation method according to any one of claims 1 to 6, characterized in that S200 specifically includes: S210, transferring the first material to a second reactor and cooling the reactor to an adsorption temperature; S220, adding the activated carbon into the second reactor, and stirring at the adsorption temperature for 2 hours to 4 hours to perform the adsorption treatment.

8. The preparation method according to claim 7, characterized in that: The adsorption temperature is 20° C.; for every 100 kg of the gluconolactone added in S110 , 20 kg of the solvent activated carbon is added in S220 accordingly.

9. The preparation method according to any one of claims 1 to 6, characterized in that: S300 specifically includes: S310, performing filter press on the first material subjected to the adsorption treatment to obtain a filtrate; S320, adding N-methylmorpholine to the filtrate and stirring, adding a mixed aqueous solution of sodium thiosulfate and sodium chloride and continuing to stir, letting stand and then separating, and extracting the first lower organic layer; S330, adding a mixed aqueous solution of sodium thiosulfate and sodium chloride to the first lower organic layer and stirring, allowing to stand and then separating, and extracting a second lower organic layer; S340, adding sodium chloride solution to the second lower organic layer with stirring, allowing to stand and then separating the liquids and removing the solvent by distillation to obtain the crude product of 2,3,4,6-tetra-O-trimethylsilyl-D-gluconolactone; S350, sending the crude product of the 2,3,4,6-tetra-O-trimethylsilyl-D-glucono-lactone into a distillation tower for distillation to obtain the finished product of the 2,3,4,6-tetra-O-trimethylsilyl-D-glucono-lactone.

10. A 2,3,4,6-tetra-O-trimethylsilyl-D-gluconolactone, characterized in that: The 2,3,4,6-tetra-O-trimethylsilyl-D-gluconolactone is obtained by the preparation method according to any one of claims 1 to 9.

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