Preparation method of sucralose glucoside

Abstract

The invention provides a preparation method of sucralose glucoside, and belongs to the technical field of organic synthesis. According to the preparation method, cane sugar is still used as a raw material and is directly chlorinated into tetrachloro cane sugar, then the tetrachloro cane sugar is dechlorinated to generate sucralose glucoside, and the obtained sucralose glucoside is hydrolyzed to prepare sucralose. According to the method, the tetrachlorosucrose is dechlorinated by adopting a single water system, so that the difficulty of subsequent solvent separation is reduced; by adopting a mixed inorganic alkali dechlorination combination, the yield of sucralose glucoside is remarkably improved, the generation of monochlorosucrose glucoside is reduced, and the hydrolysis of tetrachlorosucrose is avoided; ethyl acetate is used as a separation reagent, so that sucralose glucoside and inorganic salt can be effectively separated, and subsequent sucralose synthesis is facilitated.

Description

Technical Field

[0001] The invention belongs to the technical field of chemical synthesis, and particularly relates to a method for preparing sucralose glycoside. Background Art

[0002] Sucralose is a new, high-intensity sweetener. Due to its pure taste, high safety, and lack of human metabolism, it is widely used in food, medicine, feed, and other fields. Currently, the mainstream synthesis process for sucralose involves esterification, chlorination, alcoholysis, and refining of sucrose, using toxic and hazardous catalysts such as organotin and sodium methoxide. For example, Chinese patent CN100420695A discloses a method for preparing sucralose. This method reacts sucrose with an acylating agent in the presence of a polymer-supported organotin catalyst to produce a high-purity sucrose-6-ester. The sucrose-6-ester is then chlorinated and hydrolyzed with alkaline solution to yield sucralose. This invention uses organotin as a catalyst, which is less safe and not in line with green production practices. Therefore, it is crucial to replace traditional processes with new, green processes.

[0003] Currently, there are few reports on sucralose glycosides. Wu Feng et al. reported a method for synthesizing sucralose glycosides in Carbohydrate Research (339 (2004) 2651-2656, Compound 8). They used potassium hydroxide as a dechlorination agent and methanol-water as a solvent to produce sucralose glycosides with a yield of 35.3%. Compared to the current 50% yield of sucralose produced by traditional processes, the above method is far from achieving the goal of replacing sucralose.

[0004] Reported methods for synthesizing sucralose glycosides utilize a single strong base for dechlorination. Upon completion of the dechlorination, HCl is produced, which reacts with the strong base to form the corresponding chloride salt, causing the pH to continuously decrease during the reaction. However, providing sufficient strong base in advance, or supplementing with strong base while maintaining a constant pH, will inevitably lead to an increase in byproducts. Because the moment a strong base enters the system, a temporary local overconcentration is unavoidable. Strong bases have a good dechlorination effect on tetrachlorosucrose, quickly removing a chlorine atom to form sucralose glycosides, or they can continue dechlorination to form monochlorosucralose glycosides, resulting in an increase in byproducts, thereby affecting the yield and purity of the sucralose glycosides.

[0005] Therefore, it is necessary to provide a method for preparing sucralose glycosides with high production efficiency and in compliance with green production. Summary of the Invention

[0006] To address the shortcomings of the existing technology, the present invention provides a method for preparing sucralose glycoside, an important intermediate in the synthesis of sucralose. This method still uses sucrose as a raw material, directly chlorinating it to form tetrachlorosucrose, which is then dechlorinated to form sucralose glycoside. The resulting sucralose glycoside is then hydrolyzed to produce sucralose. Compared with traditional processes, this method eliminates the use of organotin and sodium methoxide, improving process safety.

[0007] To address the above issues, the present invention utilizes the dechlorination ability of a strong base to remove a chlorine atom from sucralose, forming sucralose glycoside. A weak base then neutralizes the HCl generated by dechlorination, thereby maintaining the pH of the system. This eliminates the need for continuous addition of strong base and avoids the increase in side reactions caused by local overconcentration. The strong base is sodium hydroxide, potassium hydroxide, or ammonia, while the weak base is sodium carbonate, potassium carbonate, sodium bicarbonate, or potassium bicarbonate, preferably a combination of sodium hydroxide and potassium carbonate.

[0008] During the implementation of the present invention, by adjusting the dechlorination conditions of sucralose, the hydrolysis of sucralose is significantly reduced on the one hand, and the generation of monochlorosucrose glycoside by-products is reduced on the other hand, thereby increasing the yield of trichlorosucralose glycosides and making it have higher application value.

[0009] Wherein, the sucralose glycoside is 1,6-dichloro-1,6-dideoxy-bD-fructofuranosyl-3,6-anhydro-4-chloro-4-deoxy-aD-galactopyranoside, and its structural formula is:

[0010]

[0011] The monochlorosucrose glycoside is 1,4:3,6-dihydro-β-D-fructose 3,6-anhydro-4-chloro-4-deoxy-α-D-galactoside, and its structural formula is

[0012]

[0013] In order to achieve the above object, the present invention adopts the following technical solutions:

[0014] In one aspect, the present invention provides a method for preparing sucralose glycoside, comprising the following steps:

[0015] Step 1: preparing an aqueous solution containing sucrose tetrachlorosucrose using sucrose as a raw material;

[0016] Step 2: adding an inorganic base to the sucralose aqueous solution obtained in step 1 to adjust the pH of the solution to obtain a mixed solution;

[0017] Step 3: heating and stirring the mixed solution obtained in step 2 to dechlorinate. After dechlorination is completed, adding inorganic acid to adjust the pH of the solution to obtain a dechlorinated solution;

[0018] Step 4: Concentrate the dechlorinated liquid obtained in step 3 to a syrupy state, then add a solvent and stir at room temperature to obtain a treated liquid;

[0019] Step 5: Filter the treated liquid obtained in step 4, and the obtained filtrate is the sucralose glycoside solution.

[0020] Furthermore, the specific operations of the above step 1 are:

[0021] (1) Sucrose was used as the raw material and dissolved in DMF solvent at 80°C, with the mass ratio of sucrose to DMF being 1:6, to obtain a sucrose DMF solution, which was cooled to room temperature for later use;

[0022] (2) Place trichloroethane in a three-necked round-bottom flask with a mass ratio of sucrose to trichloroethane of 1:10, and slowly add thionyl chloride dropwise using a constant pressure low-liquid funnel with a mass ratio of sucrose to thionyl chloride of 1:1.2. Control the temperature at 0-10°C.

[0023] (3) After the addition of thionyl chloride is completed, slowly add sucrose DMF solution, control the temperature at 0-15°C, stir and mix, and then gradually increase the temperature to 110°C. The chlorination reaction is completed to obtain a chlorinated solution;

[0024] (4) Cool the chlorinated solution to about 0°C and add liquid caustic soda to adjust the pH to 12.0. During the addition process, keep the solution temperature below 10°C. Keep the temperature for 10 minutes and adjust the pH to 7.0 with hydrochloric acid. Concentrate the solution at 70°C. Add water in small amounts and multiple times during the concentration process. The total amount of water added should be consistent with the volume of the neutralization solution.

[0025] (5) After the concentration is completed, pure water is added to make the volume 0.7 times the volume of the neutralization solution to prepare an aqueous solution containing tetrachlorosucrose.

[0026] The tetrachlorosucrose aqueous solution comprises, by mass percentage, 10%-15% of tetrachlorosucrose, 0-1% of N,N-dimethylformamide, 5%-10% of sucrose derivative impurities, and 75%-85% of water.

[0027] The inorganic base described in the above step 2 is a mixture of a strong base and a weak base, the strong base is one of sodium hydroxide, potassium hydroxide or ammonia water; the weak base is one of potassium carbonate, sodium carbonate, potassium bicarbonate or sodium bicarbonate.

[0028] Preferably, the inorganic base is a mixture of sodium hydroxide and potassium carbonate.

[0029] The specific steps of adding the inorganic base in step 2 are as follows: first, strengthen the base to adjust the pH to 10-12, and then add the weak base. The mass ratio of the weak base to sucralose is 0.5-1:1.

[0030] The dechlorination temperature in the above step 3 is 30° C.-80° C., and the time is 1 hour-24 hours.

[0031] The inorganic acid described in the above step 3 is hydrochloric acid, sulfuric acid, phosphoric acid or nitric acid; preferably hydrochloric acid.

[0032] The pH adjustment described in the above step 3 is to adjust the pH to 6-8.

[0033] The concentration temperature in the above step 4 is 50° C.-85° C., the vacuum degree is -0.05 MPa (gauge pressure)--0.1 MPa (gauge pressure), and the water content in the concentrated syrup is 0.5-1%.

[0034] The solvent in the above step 4 is ethyl acetate, and the volume ratio of the syrup to the solvent is 1:2-4.

[0035] On the other hand, the present invention also provides a sucralose glycoside prepared by the above method.

[0036] In another aspect, the present invention also provides a use of the sucralose glycoside prepared by the above method in the preparation of sucralose.

[0037] Compared with the prior art, the present invention has the following beneficial effects:

[0038] 1. The present invention uses a single water system to achieve dechlorination of sucralose, while the prior art uses a methanol-water system. The present invention reduces the difficulty of subsequent solvent separation;

[0039] 2. The present invention adopts a mixed inorganic alkali dechlorination combination to significantly improve the yield of trichlorosucrose glycosides, reduce the formation of monochlorosucrose glycosides, and avoid the hydrolysis of tetrachlorosucrose;

[0040] 3. During the implementation of the present invention, adding a small amount of ethyl acetate can effectively separate sucralose glycosides from inorganic salts, facilitating the subsequent synthesis of sucralose. DETAILED DESCRIPTION

[0041] The exemplary embodiments of the present application will be described in more detail below. Although exemplary embodiments of the present application are shown, it should be understood that the present application can be implemented in various forms and should not be limited by the embodiments set forth herein. On the contrary, these embodiments are provided to enable a more thorough understanding of the present application and to fully convey the scope of the present application to those skilled in the art.

[0042] Basic Example: Preparation of an Aqueous Sucralose Solution

[0043] The steps are:

[0044] (1) Sucrose was used as the raw material and dissolved in DMF solvent at 80°C, with the mass ratio of sucrose to DMF being 1:6, to obtain a sucrose DMF solution, which was cooled to room temperature for later use;

[0045] (2) Place trichloroethane in a three-necked round-bottom flask with a mass ratio of sucrose to trichloroethane of 1:10, and slowly add thionyl chloride dropwise using a constant pressure low-liquid funnel with a mass ratio of sucrose to thionyl chloride of 1:1.2. Control the temperature at 0-10°C.

[0046] (3) After the addition of thionyl chloride is completed, slowly add sucrose DMF solution, control the temperature at 0-15°C, stir and mix, and then gradually increase the temperature to 110°C. The chlorination reaction is completed to obtain a chlorinated solution;

[0047] (4) Cool the chlorinated solution to about 0°C and add liquid caustic soda to adjust the pH to 12.0. During the addition process, keep the solution temperature below 10°C. Keep the temperature for 10 minutes and adjust the pH to 7.0 with hydrochloric acid. Concentrate the solution at 70°C. Add water in small amounts and multiple times during the concentration process. The total amount of water added should be consistent with the volume of the neutralization solution.

[0048] (5) After the concentration is completed, pure water is added to make the volume 0.7 times the volume of the neutralization solution to prepare an aqueous solution containing tetrachlorosucrose.

[0049] Example 1 A method for preparing sucralose glycoside

[0050] The steps include:

[0051] Step 1: Prepare a sucralose aqueous solution according to the method of the basic example. The composition of the sucralose aqueous solution is shown in Table 1 below.

[0052] Table 1 Composition of sucralose aqueous solution

[0053] Serial number Components content 1 Sucralose content 12.87％ 2 Water content 78.81％ 3 DMF 0.86％ 4 impurities 7.46％

[0054] Step 2: Add 32% sodium hydroxide aqueous solution to 1 L of sucralose aqueous solution, adjust the pH to 12, then add 100 g of potassium carbonate and stir evenly to obtain a mixed solution;

[0055] Step 3: Heat the mixed solution to 55°C and stir to dechlorinate. After 2.5 hours, there is no sucralose in the solution, indicating that the dechlorination is complete. Add hydrochloric acid to adjust the pH of the solution to 6.5 to obtain a dechlorinated solution.

[0056] Step 4: Heat the dechlorinated liquid obtained in step 3 to 75° C., vacuum degree -0.09 MPa (gauge pressure), and concentrate to a syrup state with a water content of 0.53% to obtain 226 mL of treated liquid;

[0057] Step 5: Add 565 mL of ethyl acetate to the treated liquid and stir at room temperature. Chloride salt precipitates during the stirring process, which is then filtered to obtain 712 mL of sucralose glycoside solution.

[0058] The obtained sucralose glycoside solution was tested, and the results are shown in Table 2:

[0059] Table 2 Composition of sucralose glycoside solution

[0060]

[0061] Example 2 A method for preparing sucralose glycoside

[0062] The steps include:

[0063] Step 1: Prepare a sucralose aqueous solution according to the method of the basic example. The composition of the sucralose aqueous solution is shown in Table 3 below.

[0064] Table 3 Composition of sucralose aqueous solution

[0065] Serial number Components content 1 Sucralose content 13.86％ 2 Water content 78.94％ 3 DMF 0.33％ 4 impurities 6.87％

[0066] Step 2: Add 40% potassium hydroxide aqueous solution to 1 L of sucralose aqueous solution, adjust the pH to 10.5, then add 149.97 g of sodium carbonate and stir evenly to obtain a mixed solution;

[0067] Step 3: Heat the mixed solution to 45°C and stir to dechlorinate. After 20 hours, there is no sucralose in the solution, indicating that the dechlorination is complete. Add hydrochloric acid to adjust the pH of the solution to 7.1 to obtain a dechlorinated solution.

[0068] Step 4: Heat the dechlorination solution obtained in step 3 to 50° C., vacuum degree -0.05 MPa (gauge pressure), and concentrate to a syrup state with a water content of 1.00% to obtain 268 mL of treated solution;

[0069] Step 5: Add 536 mL of ethyl acetate to the treated liquid and stir at room temperature. Chloride salt precipitates during the stirring process, which is then filtered to obtain 711 mL of sucralose glycoside solution.

[0070] The obtained sucralose glycoside solution was tested, and the results are shown in Table 4:

[0071] Table 4 Composition of sucralose glycoside solution

[0072]

[0073] Example 3 A method for preparing sucralose glycoside

[0074] The steps include:

[0075] Step 1: Prepare a sucralose aqueous solution according to the method of the basic example. The composition of the sucralose aqueous solution is shown in Table 5 below.

[0076] Table 5 Composition of sucralose aqueous solution

[0077] Serial number Components content 1 Sucralose content 12.34％ 2 Water content 81.42％ 3 DMF 0.25％ 4 impurities 5.99％

[0078] Step 2: Add 40% potassium hydroxide aqueous solution to 1 L of sucralose aqueous solution, adjust the pH to 10.5, then add 149.97 g of sodium carbonate and stir evenly to obtain a mixed solution;

[0079] Step 3: Heat the mixed solution to 30°C and stir for dechlorination. After 24 hours, there is no sucralose in the solution, indicating that the dechlorination is complete. Add hydrochloric acid to adjust the pH of the solution to 7.0 to obtain a dechlorinated solution.

[0080] Step 4: Heat the dechlorinated liquid obtained in step 3 to 60° C., vacuum degree -0.08 MPa (gauge pressure), and concentrate to a syrup state with a water content of 0.6% to obtain 255 mL of treated liquid;

[0081] Step 5: Add 638 mL of ethyl acetate to the treated liquid and stir at room temperature. Chloride salt precipitates during the stirring process, which is then filtered to obtain 805 mL of sucralose glycoside solution.

[0082] The obtained sucralose glycoside solution was tested, and the results are shown in Table 6:

[0083] Table 6 Composition of sucralose glycoside solution

[0084]

[0085] Example 4 A method for preparing sucralose glycoside

[0086] The steps include:

[0087] Step 1: Prepare a sucralose aqueous solution according to the method of the basic example. The composition of the sucralose aqueous solution is shown in Table 7 below.

[0088] Table 7 Composition of sucralose aqueous solution

[0089] Serial number Components content 1 Sucralose content 12.57％ 2 Water content 80.21％ 3 DMF 0.49％ 4 impurities 6.73％

[0090] Step 2: Add 32% sodium hydroxide aqueous solution to 1 L of sucralose aqueous solution, adjust the pH of the solution to 11.5, then add 82.67 g of sodium carbonate and stir evenly to obtain a mixed solution;

[0091] Step 3: Heat the mixed solution to 40°C and stir to dechlorinate. After 22 hours, there is no sucralose in the solution, indicating that the dechlorination is complete. Add hydrochloric acid to adjust the pH of the solution to 7.5 to obtain a dechlorinated solution.

[0092] Step 4: Heat the dechlorination liquid obtained in step 3 to 65° C., vacuum degree -0.05 MPa (gauge pressure), and concentrate to a syrup state with a water content of 0.87% to obtain 238 mL of treated liquid;

[0093] Step 5: Add 714 mL of ethyl acetate to the treated liquid and stir at room temperature. Chloride salt precipitates during the stirring process, which is then filtered to obtain 869 mL of sucralose glycoside solution.

[0094] The obtained sucralose glycoside solution was tested, and the results are shown in Table 8:

[0095] Table 8 Composition of sucralose glycoside solution

[0096]

[0097] Example 5 A method for preparing sucralose glycoside

[0098] The steps include:

[0099] Step 1: Prepare a sucralose aqueous solution according to the method of the basic example. The composition of the sucralose aqueous solution is shown in Table 9 below.

[0100] Table 9 Composition of sucralose aqueous solution

[0101] Serial number Components content 1 Sucralose content 12.57％ 2 Water content 80.21％ 3 DMF 0.49％ 4 impurities 6.73％

[0102] Step 2: Add 32% sodium hydroxide aqueous solution to 1 L of sucralose aqueous solution to adjust the pH of the solution to 12, then add 124.00 g of sodium carbonate and stir evenly to obtain a mixed solution;

[0103] Step 3: Heat the mixed solution to 80°C and stir to dechlorinate. After 1 hour, there is no sucralose in the solution, indicating that the dechlorination is complete. Add hydrochloric acid to adjust the pH of the solution to 8.0 to obtain a dechlorinated solution.

[0104] Step 4: Heat the dechlorination liquid obtained in step 3 to 85° C., vacuum degree -0.1 MPa (gauge pressure), and concentrate to a syrup state with a water content of 0.5% to obtain 253 mL of treated liquid;

[0105] Step 5: Add 885 mL of ethyl acetate to the treated liquid and stir at room temperature. Chloride salt precipitates during the stirring process, which is then filtered to obtain 1052 mL of sucralose glycoside solution.

[0106] The obtained sucralose glycoside solution was tested, and the results are shown in Table 10:

[0107] Table 10 Composition of sucralose glycoside solution

[0108]

[0109] Example 6 A method for preparing sucralose glycoside

[0110] The steps include:

[0111] Step 1: Prepare a sucralose aqueous solution according to the method of the basic example. The composition of the sucralose aqueous solution is shown in Table 11 below.

[0112] Table 11 Composition of sucralose aqueous solution

[0113] Serial number Components content 1 Sucralose content 13.22％ 2 Water content 81.15％ 3 DMF 0.56％ 4 impurities 5.07％

[0114] Step 2: Add 32% sodium hydroxide aqueous solution to 1 L of sucralose aqueous solution, adjust the pH of the solution to 10.7, then add 116.34 g of sodium carbonate and stir evenly to obtain a mixed solution;

[0115] Step 3: Heat the mixed solution to 65°C and stir for dechlorination. After 17 hours, there is no sucralose in the solution, indicating that the dechlorination is complete. Add hydrochloric acid to adjust the pH of the solution to 6.0 to obtain a dechlorinated solution.

[0116] Step 4: Heat the dechlorination solution obtained in step 3 to 70° C., vacuum degree -0.08 MPa (gauge pressure), and concentrate to a syrup state with a water content of 0.7% to obtain 279 mL of treated solution;

[0117] Step 5: Add 977 mL of ethyl acetate to the treated liquid and stir at room temperature. Chloride salt precipitates during the stirring process, which is then filtered to obtain 1280 mL of sucralose glycoside solution.

[0118] The obtained sucralose glycoside solution was tested, and the results are shown in Table 12:

[0119] Table 12 Composition of sucralose glycoside solution

[0120]

[0121] Example 7 A method for preparing sucralose glycoside

[0122] The steps include:

[0123] Step 1: Prepare a sucralose aqueous solution according to the method of the basic example. The composition of the sucralose aqueous solution is shown in Table 13 below.

[0124] Table 13 Composition of sucralose aqueous solution

[0125] Serial number Components content 1 Sucralose content 12.18％ 2 Water content 80.31％ 3 DMF 0.67％ 4 impurities 6.84％

[0126] Step 2: Add 32% sodium hydroxide aqueous solution to 1 L of sucralose aqueous solution, adjust the pH of the solution to 11.8, then add 93.11 g of sodium carbonate and stir evenly to obtain a mixed solution;

[0127] Step 3: Heat the mixed solution to 75°C and stir to dechlorinate. After 3 hours, there is no sucralose in the solution, indicating that the dechlorination is complete. Add hydrochloric acid to adjust the pH of the solution to 7.8 to obtain a dechlorinated solution.

[0128] Step 4: Heat the dechlorination solution obtained in step 3 to 55° C., vacuum degree -0.1 MPa (gauge pressure), and concentrate to a syrup state with a water content of 0.75% to obtain 305 mL of treated solution;

[0129] Step 5: Add 1220 mL of ethyl acetate to the treated liquid and stir at room temperature. Chloride salt precipitates during the stirring process, which is then filtered to obtain 1411 mL of sucralose glycoside solution.

[0130] The obtained sucralose glycoside solution was tested, and the results are shown in Table 14:

[0131] Table 14 Composition of sucralose glycoside solution

[0132]

[0133] Comparative Example 1

[0134] The difference between this comparative example and Example 1 is that no inorganic base mixed with a strong base and a weak base is added, and only a strong base is added for dechlorination. The details are as follows:

[0135] Step 1: Prepare a sucralose aqueous solution according to the method of the basic example. The composition of the sucralose aqueous solution is shown in Table 15 below.

[0136] Table 15 Composition of sucralose aqueous solution

[0137] Serial number Components content 1 Sucralose content 12.87％ 2 Water content 78.81％ 3 DMF 0.86％ 4 impurities 7.46％

[0138] Step 2: Add 32% sodium hydroxide aqueous solution to 1 L of sucralose aqueous solution and adjust the pH of the solution to 12 to obtain a mixed solution;

[0139] Step 3: The mixed solution is heated to 55° C. for dechlorination. The pH value will continue to decrease during the dechlorination process. 32% sodium hydroxide aqueous solution is continuously added to maintain the solution pH at about 12. After 2.5 hours, no sucralose is left in the solution, indicating that the dechlorination is complete. Hydrochloric acid is added to adjust the solution pH to 6.5 to obtain a dechlorinated solution.

[0140] Step 4: Heat the dechlorination liquid obtained in step 3 to 75° C., vacuum degree -0.09 MPa (gauge pressure), and concentrate to a syrup state with a water content of 0.55% to obtain 238 mL of treated liquid;

[0141] Step 5: Add 565 mL of ethyl acetate to the treated liquid and stir at room temperature. Chloride salt precipitates during the stirring process, which is then filtered to obtain 824 mL of sucralose glycoside solution.

[0142] The obtained sucralose glycoside solution was tested, and the results are shown in Table 16:

[0143] Table 16 Composition of sucralose glycoside solution

[0144]

[0145] Comparative Example 2

[0146] The difference between this comparative example and Example 1 is that no inorganic base mixed with a strong base and a weak base is added, and only a weak base is added for dechlorination. The details are as follows:

[0147] Step 1: Prepare a sucralose aqueous solution according to the method of the basic example. The composition of the sucralose aqueous solution is shown in Table 17 below.

[0148] Table 17 Composition of sucralose aqueous solution

[0149] Serial number Components content 1 Sucralose content 12.87％ 2 Water content 78.81％ 3 DMF 0.86％ 4 impurities 7.46％

[0150] Step 2: Add 120 g of potassium carbonate to 1 L of sucralose aqueous solution to obtain a mixed solution;

[0151] Step 3: heating the mixed solution to 55°C for dechlorination. After 24 hours, a large amount of tetrachlorosucrose is still present in the solution, with only a small amount of trichlorosucrose glycoside generated, and no monochlorosucrose glycoside generated. After 24 hours, hydrochloric acid is added to adjust the pH of the solution to 6.5 to obtain a dechlorinated solution.

[0152] Step 4: Heat the dechlorinated liquid obtained in step 3 to 75° C., vacuum degree -0.09 MPa (gauge pressure), and concentrate to a syrup state with a water content of 0.55% to obtain 259 mL of treated liquid;

[0153] Step 5: Add 565 mL of ethyl acetate to the treated liquid and stir at room temperature. Chloride salt precipitates during the stirring process, which is then filtered to obtain 818 mL of sucralose glycoside solution.

[0154] The obtained sucralose glycoside solution was tested, and the results are shown in Table 18:

[0155] Table 18 Composition of sucralose glycoside solution

[0156]

[0157] The present invention obtains a sucralose glycoside solution through dechlorination, concentrated drying, and impurity removal. A single water system is used to achieve dechlorination of sucralose tetrachlorohydrate, thereby reducing the difficulty of subsequent solvent separation. A mixed inorganic alkali dechlorination combination is used to significantly improve the yield of sucralose glycoside, reduce the generation of monochlorosucralose glycoside, and avoid the hydrolysis of sucralose tetrachlorohydrate. Adding a small amount of ethyl acetate can effectively separate sucralose glycoside and inorganic salt, thereby facilitating subsequent sucralose synthesis.

[0158] The above description is only a specific embodiment of the present application. Based on the above teachings of the present application, those skilled in the art may make other improvements or modifications based on the above embodiments. Those skilled in the art should understand that the above description is only a better explanation of the purpose of the present application, and the scope of protection of the present application shall be based on the scope of protection of the claims.

Claims

1. A method for preparing sucralose glycoside, characterized in that: The steps include: Step 1: preparing an aqueous solution containing sucrose tetrachlorohydrate using sucrose as a raw material; Step 2: adding an inorganic base to the sucralose aqueous solution obtained in step 1 to adjust the pH of the solution to obtain a mixed solution; Step 3: heating and stirring the mixed solution obtained in step 2 to dechlorinate. After dechlorination is completed, adding inorganic acid to adjust the pH of the solution to obtain a dechlorinated solution; Step 4: Concentrate the dechlorinated liquid obtained in step 3 to a syrupy state, then add a solvent and stir at room temperature to obtain a treated liquid; Step 5: Filter the treated liquid obtained in step 4, and the obtained filtrate is the sucralose glycoside solution.

2. The preparation method according to claim 1, wherein: The sucralose aqueous solution in step 1 comprises, by mass percentage, 10%-15% sucralose, 0-1% N,N-dimethylformamide, 5%-10% sucrose derivative impurities, and 75%-85% water.

3. The preparation method according to claim 1, wherein: The inorganic base described in step 2 is a mixture of a strong base and a weak base.

4. The preparation method according to claim 3, wherein: The strong base is one of sodium hydroxide, potassium hydroxide or ammonia water.

5. The preparation method according to claim 4, characterized in that: The strong base is sodium hydroxide.

6. The preparation method according to claim 3, wherein: The weak base is one of potassium carbonate, sodium carbonate, potassium bicarbonate or sodium bicarbonate.

7. The preparation method according to claim 6, characterized in that: The weak base is potassium carbonate.

8. The preparation method according to claim 1, wherein: The specific steps of adding the inorganic base in step 2 are: first strengthen the base to adjust the pH to 10-12, and then add the weak base.

9. The preparation method according to claim 8, characterized in that: The mass ratio of the weak base to sucralose is 0.5-1:

1.

10. The preparation method according to claim 1, characterized in that: The dechlorination temperature in step 3 is 30° C.-80° C., and the dechlorination time is 1 h-24 h.

11. The preparation method according to claim 1, characterized in that: The inorganic acid described in step 3 is hydrochloric acid; the pH adjustment is to adjust the pH to 6-8.

12. The preparation method according to claim 1, characterized in that: The concentration temperature in step 4 is 50° C.-85° C., the vacuum degree is -0.05 MPa--0.1 MPa, and the water content in the concentrated syrup is 0.5-1%.

13. The preparation method according to claim 1, characterized in that: The solvent described in step 4 is ethyl acetate.

14. The preparation method according to claim 13, characterized in that: The volume ratio of the syrup to the solvent is 1:2-4.

15. Sucralose glycoside prepared by the preparation method according to any one of claims 1 to 14.

16. Use of sucralose glycoside prepared by the preparation method according to any one of claims 1 to 14 in the preparation of sucralose.

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