- Tin(IV)-functionalised polymer supports; non-toxic and practical reagents for regioselective acetylation of sucrose
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Polymer-supported butyltin(IV) reagents have been surveyed for regioselectivity in acetylation of sucrose. Polymer-supported butyltin(IV) dichloride 8 catalysed the acetylation of sucrose to give a 59% yield of 6-O-acetyl sucrose 3, the precursor of sucralose. The yield is close to that of a previously reported process involving dibutyltin(IV) oxide (Bu2SnO). The spent polymeric resin could readily be regenerated and can be subsequently used in further synthetic reactions.
- Macindoe, Wallace M.,Williams, Andrew,Khan, Riaz
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Read Online
- Monotin organic compound, preparation method and application thereof
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The invention provides a single tin organic compound which is used for synthesizing sucrose-6-carboxylic ester, and the compound is a compound represented by the following formula (1), R , R and R respectively and independently represent straight-chain or branched-chain saturated alkyl groups of C1-C8, straight-chain or branched-chain unsaturated alkyl groups of C2-C8, substituted or unsubstituted saturated cycloalkyl groups of C3-C8, substituted or unsubstituted unsaturated cycloalkyl groups of C3-C8, or aryl groups or substituted aryl groups of C6-C12; and R4 represents a straight chain or branched chain saturated alkyl group of C1 to C6 or an aryl group or a substituted aryl group of C6 to C12. According to the single-tin organic compound, in the process of synthesizing sucrose-6-carboxylic ester, metering and feeding can be accurately carried out, meanwhile, the recovery rate of a catalyst is increased, follow-up chlorination side reactions are reduced, the reaction is fast, energy consumption is small, and the yield in unit volume is higher.
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Paragraph 0101-0112
(2021/05/08)
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- Sucrose-6-ester production equipment and production method
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The invention provides sucrose-6-ester production equipment and a production method. The equipment comprises a shell, a film scraping device and a base, the film scraping device is arranged on the base, and the shell covers the outer sides of the film scraping device and the base; the shell is provided with a reaction liquid feeding hole and a condensed water outlet; the base is provided with a carboxylic ester feeding pipe, a reaction product discharging pipe and a reaction channel connected with the carboxylic ester feeding pipe; the film scraping device comprises a temperature control device, a rotating pipe and a plurality of scraping pieces arranged on the inner wall of the rotating pipe, and the outer edges of the scraping pieces abut against the outer wall of the temperature control device. The rotating pipe can rotate around the temperature control device, so that the scraper blade can scrape reaction liquid which enters from the reaction liquid feeding hole and flows down along the outer wall of the temperature control device into a liquid film on the outer wall of the temperature control device, and the liquid film is separated into evaporation residual liquid and water vapor. According to the invention, the integrated design of a separation device and a reaction device is realized, the volume of production equipment is reduced, the occupied area is saved, the yield of sucrose-6-ester is improved, and the production cost is greatly saved.
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Paragraph 0084-0093
(2021/05/29)
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- Preparation method of sucrose-6-acetate
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The invention relates to a synthesis method of sucrose-6-acetate. The synthesis method comprises the following steps: (1) adding sucrose into an organic solvent DMF (Dimethyl Formamide), heating to 80to 85 DEG C for dissolving, then cooling to 75 DEG C, adding an alkaline solvent and an organic tin compound, and refluxing and reacting with water for 5 to 8 hours, wherein the reflux temperature iscontrolled to be 70 to 75 DEG C; (2) cooling a reactant to -10 DEG C or below, dropwise adding acetic anhydride in the reactant under a stirring condition, and reacting for 3 hours; (3) adding an appropriate amount of water in a reaction solution, extracting the organic tin compound by using a non-polar organic solvent, recycling and reusing after concentrating, and carrying out vacuum distillation on a residual extracted solution for removing the organic solvent, thus obtaining a sucrose-6-acetate solution. A preparation method disclosed by the invention has the following advantages that through the technology disclosed by the invention, the reaction time is reduced, generation of side reaction is reduced, the cost is low, the energy consumption is reduced, and the yield of the sucrose-6-acetate is up to 91 percent.
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Paragraph 0009-0013
(2019/04/17)
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- Recrystallization method of sucrose-6-acetate and applications thereof
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The invention discloses a recrystallization method of sucrose-6-acetate, and applications thereof. The recrystallization method comprise following steps: a solvent is added into a sucrose-6-acetate mixture obtained via sucrose esterification; and stirring, dissolving, filtering, and drying are carried out so as to obtain sucrose-6-acetate, wherein the solvent is a mixture of a nitrile solvent and an ether solvent. The recrystallization method is capable of increasing sucrose-6-acetate purity, and reducing adverse influences on subsequent chlorination.
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Paragraph 0027-0029; 0051
(2017/09/01)
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- A one-pot synthesis of synthetic trichloro-6-acetate method
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The invention discloses a method for synthesizing sucralose-6-acetate by using a one-pot method. The method comprises the following steps of: adding saccharose, trimethyl orthoacetate and a sulfonated bamboo charcoal catalyst in a reaction vessel to carry out hydroxyl protection reaction on the C-6 position of the saccharose, after the reaction is ended completely, adding a phthalate-based cationic dimeric surfactant as shown in the formula (I) to carry out a chlorination reaction, after the reaction is ended, extracting by using ethyl acetate, decoloring by using active carbon, concentrating and crystallizing to obtain a sucralose-6-acetate product, wherein R in the formula (I) is alkyl, allyl or benzyl from C1 to C10. The method has the characteristics of simplicity in process operation, good technical performance, few three wastes, convenience for aftertreatment and recyclable reaction system so as to be an economical and practical environment friendly technology.
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Paragraph 0040; 0043; 0044
(2017/02/09)
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- Sucrose-6-acetate synthesis method
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The invention discloses a synthesis method of sugar cane-6-acetic acid ester. The synthesis method of the sugar cane-6-acetic acid ester comprises the following steps: in a mixed solvent of water and dimethyl formamide, mixing and dissolving sugar cane and an acid-binding agent at the temperature of 0-5 DEG C; dropwise adding a dimethyl formamide solution of acetic anhydride at 0-5 DEG C under a stirring condition, and reacting for 4-6 hours; after the reaction is finished, carrying out reduced pressure distillation for removing the water and dimethyl formamide solvents, adding a mixed solvent of acetone and methyl alcohol, recrystallizing, filtering, washing and drying, thus obtaining the sugar cane-6-acetic acid ester product. The synthesis method of the sugar cane-6-acetic acid ester has the advantages that acetic anhydride is used for doing sugar cane-6 hydroxyl in a new reaction system, so that an expensive and toxic reagent is not used, cost is low, and environmental friendliness is realized; reaction is carried out at a low temperature, so that product quality and yield can be improved, and the yield can be 72-85%.
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Paragraph 0026; 0027
(2017/03/14)
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- Probing substrate promiscuity of amylosucrase from neisseria polysaccharea
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The amylosucrase from Neisseria polysaccharea (NpAS) naturally catalyzes the synthesis of a variety of products from sucrose and shows signs of plasticity of its active site. To explore further this promiscuity, the tolerance of amylosucrase towards different donor and acceptor substrates was investigated. The selection of alternate donor substrates was first made on the basis of preliminary molecular modeling studies. From 11 potential donors harboring selective derivatizations that were experimentally evaluated, only p-nitrophenyl-α-D-glucopyranoside was used by the wild-type enzyme, and this underlines the high specificity of the -1 subsite of NpAS for glucosyl donor substrates. The acceptor substrate promiscuity was further explored by screening 20 hydroxylated molecules, including D- and L-monosaccharides as well as polyols. With the exception of one compound, all were successfully glucosylated, and this showcases the tremendous plasticity of the +1 subsite of NpAS, which is responsible for acceptor recognition. The products obtained from the transglucosylation reactions of three selected acceptors were characterized, and they revealed original structures and enzyme enantiopreference, which were more particularly analyzed by insilico docking analyses.
- Daude, David,Champion, Elise,Morel, Sandrine,Guieysse, David,Remaud-Simeon, Magali,Andre, Isabelle
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p. 2288 - 2295
(2013/08/23)
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- Low Temperature, Single Solvent Process for the Production of Sucrose-6-Ester
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A method for the preparation of a sucrose-6-ester is disclosed. In a first step of the method, sucrose in a polar aprotic solvent is reacted with an organotin-based acylation promoter. The water of reaction is removed at a temperature that does not exceed about 80° C. In one aspect, the water is removed by distillation of part of the polar aprotic solvent at reduced pressure. In a second step, a carboxylic acid anhydride is added. In one aspect, the resulting reaction mixture is maintained at a temperature of 10° C. or less for a period of time sufficient to produce a sucrose-6-ester. The sucrose-6-ester can be converted to sucralose.
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Page/Page column 8
(2011/04/25)
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- Process for the production of sucrose-6-ester
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A process for the production of sucrose-6-ester is disclosed. The process includes, in order, the steps of: (a) providing a first reaction mixture including sucrose, a reaction vehicle, and an organotin-based acylation promoter;(b) removing water from the first reaction mixture to afford a second reaction mixture that is substantially free from water; and(c) adding a carboxylic acid anhydride to the second reaction mixture to afford a third reaction mixture, thereby producing a sucrose-6-ester;wherein:during step (b), the removing of water includes distillation of water with the reaction vehicle using an apparatus supplying a heat flux of from 500 to 25,000 BTU/hrft2 (1577 to 78865 W/m2) selected from the group consisting of wiped film evaporators, agitated thin film evaporators, falling film evaporators and rising film evaporators.
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Page/Page column 9
(2011/04/25)
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- Method of sucralose synthesis yield
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The invention discloses a method for improving the yield of sucralose, including reacting sucrose to produce sucrose-6-acetate in the existence of an azo reagent as a catalyst and acetic acid as an acylating agent in a proper solvent; then reacting sucrose-6-acetate with a proper chlorinating agent to produce sucralose-6-acetate in a non-proton polar solvent with TCA as a catalyst; and at last, alcoholyzing sucralose-6-acetate in KOH/methanol to obtain sucralose.
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Page/Page column 4; 5
(2011/02/26)
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- Removal of pyridine and pyridine analogs from reaction mass containing sucrose esters
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A process of removal of pyridine or a pyridine analogue from a composition or a Process Stream in a process of production of 4,1′, 6′ trichlorogalactosucrose is described comprising reacting pyridine with an acid, the said acid being used preferably in gaseous form, achieving complete precipitation of the salt of pyridine in higher alcoholic solvents and non-polar solvents, filtering off the precipitate of the said salt of pyridine to achieve removal of pyridine from the reaction system and optionally regenerating and recovering pyridine by reacting the said salt with alkali.
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Page/Page column 2
(2010/09/07)
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- BASE-ASSISTED FORMATION OF TIN-SOCROSE ADDUCTS
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A method of forming a sucrose-6-ester includes in sequence the steps of: a) contacting sucrose with a organotin-based acylation promoter in a solvent in the presence of a base selected from amines and basic alkali metal salts; b) removing water to form a tin-sucrose adduct; and c) contacting the tin-sucrose adduct with an acylating agent to form the sucrose- 6-ester. The sucrose-6-ester may then be converted to sucralose.
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Page/Page column 9-12
(2010/11/03)
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- Novel process for preparing sucrose-6-esters
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A process for preparing a sucrose-6-ester, a key intermediate to sucralose. The process contains (a) reacting sucrose with a di(hydrocarbyl)tin oxide or a 1,3-diacyloxy-1,1,3,3-tetra(hydrocarbyl)distannoxane in the presence of a secondary alcohol and an organic polar aprotic solvent, to prepare a mixture comprising 1,3-di-(6-O-sucrose)-1,1,3,3-tetra(hydrocarbyl)distannoxane and the secondary alcohol; and (b) adding an acylating agent to the mixture, thereby acylating the 1,3-di-(6-O-sucrose)-1,1,3,3-tetra(hydrocarbyl)distannoxane to prepare a sucrose-6-ester.
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Page/Page column 3-4
(2009/04/24)
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- Tin Mediated Regioselective Synthesis of Sucrose-6-Esters
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A method is disclosed for regioselective synthesis of sucrose-6-acetate via formation of a novel sucrose-tin adduct using sucrose and DBTO. The novel tin adduct can be represented by a formula (6-O-sucrose)-O—Snbutyl2-O-(6-O-sucrose) or as 1,3.(di O-sucrose) dibutyl stannylene. The adduct is acylated to yield sucrose-6-acetate or sucrose-6-benzoate as major product.
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Page/Page column 3
(2009/05/29)
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- PROCESS FOR THE PREPARATION OF SUCROSE-6-ESTER BY ESTERIFICATION IN THE PRESENCE OF SOLID SUPERACID CATALYST
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One embodiment of the present invention is a process of making sucrose-6-ester from sucrose by transesterification in the presence of a solid super acid catalyst such as SO42?—TiO2/Al2O3 or SO42?—TiO2. The sucrose-6-acetate is then chlorinated to afford sucralose-6-acetate, using BTC or thionyl chloride. Sucralose-6-acetate is converted into TPSGA for the purpose of purification. TPSGA is de-esterified by sodium methoxide/methanol or sodium ethoxide/ethanol to give sucralose.
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Page/Page column 2
(2008/06/13)
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- METHOD FOR THE SYNTHESIS OF SUCROSE-6-ESTERS
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The present application discloses a process for the synthesis of a sucrose-6-ester comprising: (a) forming a first reaction mixture comprising sucrose, a polar aprotic solvent, and an organotin-based acylation promoter; (b) removal of water from said first reaction mixture by contacting, in a continuous counter-current manner, with gas or solvent vapour capable of removing water at a temperature, pressure and residence time sufficient to afford a second reaction mixture which is substantially free from water; followed by (c) adding a carboxylic anhydride to said second reaction mixture to afford a third reaction mixture, and maintaining said third reaction mixture at a temperature and for a period of time sufficient to produce a sucrose-6-ester. The sucrose-6-ester can be used to make sucralose.
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Page/Page column 10-12
(2008/12/07)
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- Method for synthesizing sucrose-6-acetic ester
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The present invention discloses a method of synthesizing sucrose-6-acetic ester, comprising the following steps: adding sucrose into a polar aprotic solvent, and stirring the solvent to dissolve it, then generate a suspension solution of sucrose; adding a acetylation agent acetylnitrile into said suspension solution and stirring the solution; adding water into the aforesaid reaction solution, and then concentrating it to generate a concentrated product; adding a crystalline solvent into the concentrated product, stirring to dissolve it, and depositing for crystallization, then filtering and drying it to get a product of sucrose-6-acetic ester. The benefit of the present invention is that the method of synthesizing sucrose-6-acetic ester has simple operation, mild reaction condition, high selectivity, high yield, and is suitable for industrial production.
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Page/Page column 1; 2
(2008/12/04)
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- Process for Preparing Sucrose-6-ester
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This invention relates to a method for preparing a sucrose-6-ester. The method includes (i) reacting sucrose with a N,N-dimethylcarboxamide dimethyl acetal in an inert aprotic solvent to form a cyclic acetal of formula (I): wherein R is C1-C6 alkyl, C3-C20 cycloalkyl, C1-C20 heterocycloalkyl, aryl, or heteroaryl; and (ii) subjecting the cyclic acetal to a mild acidic or neutral hydrolysis to provide a sucrose-6-ester of formula (II):
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Page/Page column 2-3
(2008/06/13)
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