CN105801360A - Method for preparing dibromohexanehexol - Google Patents
Method for preparing dibromohexanehexol Download PDFInfo
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- CN105801360A CN105801360A CN201410838245.1A CN201410838245A CN105801360A CN 105801360 A CN105801360 A CN 105801360A CN 201410838245 A CN201410838245 A CN 201410838245A CN 105801360 A CN105801360 A CN 105801360A
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Abstract
The invention relates to a method for preparing dibromohexanehexol. The method for preparing dibromohexanehexol is used, and products whose average yield is 55% and average purity is 80% or above are obtained; and compared with the prior art, the effect is obviously better.
Description
Technical field
The present invention relates to chemical drugs field, the preparation method being specifically related to a kind of dibromo hexanhexol.
Background technology
The compositions that hexanhexol is made up of fatty acid ester and the many alcohol of no esterification of hexitan (sorbitan), wherein no esterification many alcohol content is 0.05-6.59%.Common hexanhexol has mannitol, dulcitol, sorbitol etc. several.
The reaction generating dibromo hexanhexol through bromination reaction due to hexanhexol is reversible reaction, when reaction just starts, owing in reaction mass, bromine content is high, and overresponse, easily generate terbromide, tetrabormated compound；Along with the carrying out of reaction, material concentration reduces, and the generation of dibromo hexanhexol is increasingly difficult to, and because adding bromine deficiency during substitution reaction, can generate monobromo compound；Factors above is the main cause causing dibromo hexanhexol yield too low.During according to published technical method large-scale production dibromo hexitol, the dibromo hexitol crystallization purity of gained is not high, yield is unstable.In order to improve the yield of large-scale production, it is necessary to saving improvement of production process on the basis of cost.
Prepare dibromo hexanhexol technology by existing, outside dehydrogenation bromic acid, if using remaining bromating agent, making consumption mostly be more than 10 times ability complete reactions of hexanhexol weight, causing waste of solvent and environmental pollution.When selection hydrobromic acid is bromating agent, if obtaining the dibromo hexanhexol that purity is higher, also must select highly purified solvent, as more than hydrobromic acid solution that concentration is 69%, the dibromo hexanhexol of about 70% purity could be obtained, if adopting low concentration hydrobromic acid solution yield generally below 10%.The maximum concentration hydrobromic acid being commercially available on market is 62%, exceedes this concentration, it is necessary to oneself preparation, complex process, operating process danger close, and differs and be successfully prepared surely.
Summary of the invention
The preparation method that it is an object of the invention to provide dibromo hexanhexol.
The preparation method of dibromo hexanhexol of the present invention includes bromination step, it is characterised in that: hexanhexol bromination process course of reaction carries out under elevated pressure.
Preferably: described being pressurised into passes into the pressurization of gas fixation pressure or gradient type pressurization.
Preferably: described gas is be not involved in reaction and the gas that will not reaction be had undesirable effect.
Preferably: described gas is noble gas, carbon dioxide or helium.
Preferably: described fixation pressure pressurizes, and pressure limit is 0.1-3.0Mpa.
Preferably: described gradient type pressurizes, pressure is not less than 0.5Mpa when reaction terminates.
Preferably: described hexanhexol is mannitol, dulcitol, sorbitol.
The preparation method of dibromo hexanhexol of the present invention, it is characterized in that, described bromination process comprises the steps: that taking hexanhexol puts in reaction vessel, adds hydrobromic acid solution, reacting by heating 2-24 hour, heating-up temperature is 30-90 DEG C, in the response time of 2-24 hour, pressure is started to step up by 0Mpa, until being finally not less than 0.5Mpa, being stirred continuously during reaction, reaction terminates and obtains dibromo hexanhexol solution.
Preferably: temperature during described reaction is 40-80 DEG C.
Preferably: temperature during described reaction is 70 DEG C.
Preferably: described hydrobromic acid solution concentration is 20-80%.
Preferably: described hydrobromic acid solution concentration is 30-62%.
Preferably: described hydrobromic acid solution concentration is 40%.
Preferably: 2-15 times that amount is hexanhexol weight of described hydrobromic acid solution.
The preparation method of dibromo hexanhexol of the present invention, it is characterised in that comprise the steps:
1) take hexanhexol and put in reaction vessel, add hexanhexol weight 2-15 times, concentration is the hydrobromic acid solution of 20-80%, reacting by heating 2-24 hour, heating-up temperature was 30-90 DEG C, and heating is to 30-90 DEG C, the response time of 2-24 hour, in the response time of 2-24 hour, pressure is started to step up by 0Mpa, until being finally not less than 0.5Mpa, being stirred continuously during reaction, reaction terminates and obtains dibromo hexanhexol solution；
2) dibromo hexanhexol solution left at room temperature more than 12 hours, filters, obtains dibromo hexanhexol coarse crystallization；
3) dibromo hexanhexol coarse crystallization recrystallizing methanol, obtains dibromo hexanhexol.
After the present invention have passed through substantial amounts of experimentation and gropes, find in dibromo hexanhexol preparation process, pressure is a very crucial factor, by controlling the pressure of course of reaction, enable to hexanhexol bromination reaction and there is higher dibromo selectivity, overcome the problem that hexanhexol bromination reaction side reaction is too many, it is possible to be obviously improved dibromo hexanhexol yield, and finally can obtain the crystallization that purity is higher.
The present invention is by passing through pressure influence reaction process in bromination process, hydrobromic acid solution concentration selectivity is not strong, without requiring the hydrobromic acid solution using high concentration, hydrobromic acid solution concentration is between 20-80%, reaction all can be made to carry out smoothly and well, and the yield of dibromo hexanhexol and purity can be made all to be significantly improved.
Present invention also offers the preferred preparation method of dibromo hexanhexol, and give detailed process and technological parameter, by this preferred process control, make bromination reaction process coordinates bromating agent and the reaction temperature of debita spissitudo, by the response situation of different periods, step up reaction pressure, control pressure within the specific limits, hexanhexol can be made optionally to be brominated agent in bromination process and to replace two primary hydroxyls generation dibromo hexanhexol, can further reduce the generation of by-product, thus better improving yield and the purity of industrialization dibromo hexanhexol.
The preparation method of a kind of dibromo hexanhexol provided by the invention has the advantage that
1, dibromo hexanhexol purity is high: the obtained dibromo hexanhexol product purity of prior art, mostly below 70%, adopts the dibromo hexanhexol that the present invention is prepared from, and purity reaches 80-90%.
2, adopt the present invention to be applied to industrialization and produce yield height during dibromo hexanhexol: prior art is appropriate only for laboratory lab scale, large-scale production dibromo hexanhexol yield is mostly below 40%, present invention process safe and reasonable, prepared dibromo hexanhexol average yield is 50-70%.
Detailed description of the invention
Further illustrate the present invention by the examples below.It should be understood that embodiments of the invention are an illustration for the present invention rather than limitation of the present invention.The simple modifications that the present invention is carried out by the essence according to the present invention broadly falls into the scope of protection of present invention.Except as otherwise noted, the percent of the amount of alcohol in the present invention is percentage by volume, and v/v represents the volume ratio of solution.
Embodiment 1:
Taking 10kg dulcitol and put in reactor, addition dulcitol weight 15 times, concentration are the hydrobromic acid solution of 40%, and heating in water bath is to 70 DEG C, and insulation is continuous stirring reaction 15 hours also, pass into nitrogen and be forced into 2.4MPa during reaction；Reaction terminates to obtain mitolactol solution；Mitolactol solution left at room temperature 24 hours, filters, obtains mitolactol coarse crystallization；Mitolactol coarse crystallization adds the methanol of 100 times of coarse crystallization weight, recrystallization at 2 DEG C, obtains mitolactol.
Experimental result: mitolactol average yield 55%, average purity is 82%.
Embodiment 2:
Taking 10kg mannitol and put in reactor, adding mannitol weight 12 times, concentration is the hydrobromic acid solution of 70%, heating in water bath to 60 DEG C, insulation constantly stirring reaction 10 hours, pass into argon pressurization during reaction to 3.0MPa；Reaction terminates to obtain mitobronitol solution；Mitobronitol solution left at room temperature 15 hours, filters, obtains mitobronitol coarse crystallization；Mitobronitol coarse crystallization adds the methanol of 120 times of coarse crystallization weight, recrystallization at 2 DEG C, obtains mitobronitol.
Experimental result: mitobronitol average yield 56%, average purity is 84%.
Embodiment 3:
Taking 10kg sorbitol and put in reactor, addition sorbitol weight 8 times, concentration are the hydrobromic acid solution of 62%, and heating in water bath is to 30 DEG C, and insulation is continuous stirring reaction 20 hours also, pass into nitrogen and be forced into 0.1MPa during reaction；Reaction terminates to obtain dibromo sorbitol solution；Dibromo sorbitol solution left at room temperature 15 hours, filters, obtains dibromo sorbitol coarse crystallization；Dibromo sorbitol coarse crystallization adds the methanol of 80 times of coarse crystallization weight, recrystallization at 4 DEG C, obtains dibromo sorbitol.
Experimental result: dibromo sorbitol average yield 53%, average purity is 85%.
Embodiment 4:
Taking 10kg mannitol and put in reactor, addition mannitol weight 2 times, concentration are the hydrobromic acid solution of 20%, and heating in water bath is to 30 DEG C, insulation constantly stirring reaction 2 hours, pass into argon pressurization during reaction, range for response time pressurization: 0-1 hour, pressure was progressively added to 0.5MPa by 0MPa；1-2 hour, pressure was progressively added to 1.2MPa by 0.5MPa；Reaction terminates to obtain mitobronitol solution；Mitobronitol solution left at room temperature 12 hours, filters, obtains mitobronitol coarse crystallization；Mitobronitol coarse crystallization adds the methanol of 80 times of coarse crystallization weight, recrystallization at 6 DEG C, obtains mitobronitol.
Experimental result: mitobronitol average yield 57%, average purity is 84%.
Embodiment 5:
Taking 10kg sorbitol and put in reactor, addition sorbitol weight 6 times, concentration are the hydrobromic acid solution of 30%, and heating in water bath is to 90 DEG C, insulation constantly stirring reaction 8 hours, pass into helium pressurization during reaction, range for response time pressurization: 0-1 hour, pressure was progressively added to 0.1MPa by 0MPa；1-4 hour, pressure was progressively added to 0.3MPa by 0.1MPa；4-8 hour, pressure was progressively added to 0.5MPa by 0.3MPa；Reaction terminates to obtain dibromo sorbitol solution；Dibromo sorbitol solution left at room temperature 30 hours, filters, obtains dibromo sorbitol coarse crystallization；Dibromo sorbitol coarse crystallization adds the methanol of 70 times of coarse crystallization weight, recrystallization at 8 DEG C, obtains dibromo sorbitol.
Experimental result: dibromo sorbitol average yield 58%, average purity is 86%.
Embodiment 6:
Take 10kg dulcitol and put in reactor, add dulcitol weight 4 times, concentration is the hydrobromic acid solution of 62%, heating in water bath is to 40 DEG C, insulation constantly stirring reaction 24 hours, carbon dioxide pressurization is passed into during reaction, range for response time pressurization: 0-1 hour, pressure was progressively added to 0.1MPa by 0MPa；1-6 hour, pressure was progressively added to 0.5MPa by 0.1MPa；6-12 hour, pressure was progressively added to 1.0MPa by 0.5MPa；12-18 hour, pressure was progressively added to 1.5MPa by 1.0MPa；18-24 hour, pressure was progressively added to 2.0MPa by 1.5MPa；Reaction terminates to obtain mitolactol solution；Mitolactol solution left at room temperature 48 hours, filters, obtains mitolactol coarse crystallization；Mitolactol coarse crystallization adds the methanol of 60 times of coarse crystallization weight, recrystallization at 4 DEG C, obtains mitolactol.
Experimental result: mitolactol average yield 56%, average purity is 86%.
Embodiment 7:
Take 10kg dulcitol and put in reactor, add dulcitol weight 7 times, concentration is the hydrobromic acid solution of 50%, heating in water bath is to 80 DEG C, insulation constantly stirring reaction 16 hours, carbon dioxide pressurization is passed into during reaction, range for response time pressurization: 0-1 hour, pressure was progressively added to 0.1MPa by 0MPa；1-5 hour, pressure was progressively added to 0.4MPa by 0.1MPa；6-12 hour, pressure was progressively added to 1.9MPa by 0.4MPa；12-16 hour, pressure was progressively added to 3.0MPa by 1.9MPa；Reaction terminates to obtain mitolactol solution；Mitolactol solution left at room temperature 18 hours, filters, obtains mitolactol coarse crystallization；Mitolactol coarse crystallization adds the methanol of 50 times of coarse crystallization weight, recrystallization at 3 DEG C, obtains mitolactol.
Experimental result: mitolactol average yield 54%, average purity is 84%.
Embodiment 8:
Take 8kg dulcitol and put in reactor, add dulcitol weight 10 times, concentration is the hydrobromic acid solution of 80%, heating in water bath is to 50 DEG C, insulation constantly stirring reaction 18 hours, nitrogen pressurization is passed into during reaction, range for response time pressurization: 0-1 hour, pressure was progressively added to 0.1MPa by 0MPa；1-6 hour, pressure was progressively added to 0.4MPa by 0.1MPa；6-12 hour, pressure was progressively added to 0.7MPa by 0.4MPa；12-18 hour, pressure was progressively added to 1.0MPa by 0.7MPa；Reaction terminates to obtain mitolactol solution；Mitolactol solution left at room temperature 20 hours, filters, obtains mitolactol coarse crystallization；Mitolactol coarse crystallization adds the methanol of 100 times of coarse crystallization weight, recrystallization at 7 DEG C, obtains mitolactol.
Experimental result: mitolactol average yield 55%, average purity is 85%.
Comparative example 1: with reference to technical solution of the present invention 1, no pressure
Taking 10kg dulcitol and put in reactor, addition dulcitol weight 15 times, concentration are the hydrobromic acid solution of 40%, and heating in water bath is to 70 DEG C, and insulation constantly stirring reaction 15 hours, reaction terminates to obtain mitolactol solution；Mitolactol solution left at room temperature 24 hours, filters, obtains mitolactol coarse crystallization；Mitolactol coarse crystallization adds the methanol of 100 times of coarse crystallization weight, recrystallization at 2 DEG C, obtains mitolactol.
Experimental result: mitolactol average yield 35%, average purity is 65%.
Comparative example 2: with reference to technical solution of the present invention 2, no pressure
Taking 10kg mannitol and put in reactor, addition mannitol weight 2 times, concentration are the hydrobromic acid solution of 20%, and heating in water bath is to 30 DEG C, and insulation constantly stirring reaction 2 hours, reaction terminates to obtain mitobronitol solution；Mitobronitol solution left at room temperature 12 hours, filters, obtains mitobronitol coarse crystallization；Mitobronitol coarse crystallization adds the methanol of 80 times of coarse crystallization weight, recrystallization at 6 DEG C, obtains mitobronitol.
Experimental result: mitobronitol average yield 36%, average purity is 64%.
Comparative example 3: with reference to technical solution of the present invention 3, no pressure
Taking 10kg sorbitol and put in reactor, addition sorbitol weight 6 times, concentration are the hydrobromic acid solution of 30%, and heating in water bath is to 90 DEG C, and insulation constantly stirring reaction 8 hours, reaction terminates to obtain dibromo sorbitol solution；Dibromo sorbitol solution left at room temperature 30 hours, filters, obtains dibromo sorbitol coarse crystallization；Dibromo sorbitol coarse crystallization adds the methanol of 70 times of coarse crystallization weight, recrystallization at 8 DEG C, obtains dibromo sorbitol.
Experimental result: dibromo sorbitol average yield 37%, average purity is 63%.
Comparative example 4: with reference to technical solution of the present invention 4, no pressure
Taking 10kg dulcitol and put in reactor, addition dulcitol weight 4 times, concentration are the hydrobromic acid solution of 62%, and heating in water bath is to 40 DEG C, and insulation is continuous stirring reaction 24 hours also；Reaction terminates to obtain mitolactol solution；Mitolactol solution left at room temperature 48 hours, filters, obtains mitolactol coarse crystallization；Mitolactol coarse crystallization adds the methanol of 60 times of coarse crystallization weight, recrystallization at 4 DEG C, obtains mitolactol.
Experimental result: mitolactol average yield 34%, average purity is 64%.
Comparative example 5: with reference to technical solution of the present invention 5, no pressure
Taking 10kg dulcitol and put in reactor, addition dulcitol weight 7 times, concentration are the hydrobromic acid solution of 50%, and heating in water bath is to 80 DEG C, and insulation constantly stirring reaction 16 hours, reaction terminates to obtain mitolactol solution；Mitolactol solution left at room temperature 18 hours, filters, obtains mitolactol coarse crystallization；Mitolactol coarse crystallization adds the methanol of 50 times of coarse crystallization weight, recrystallization at 3 DEG C, obtains mitolactol.
Experimental result: mitolactol average yield 32%, average purity is 59%.
Comparative example 6: with reference to technical solution of the present invention 6, no pressure
Taking 8kg dulcitol and put in reactor, addition dulcitol weight 10 times, concentration are the hydrobromic acid solution of 80%, and heating in water bath is to 50 DEG C, and insulation is continuous stirring reaction 18 hours also；Reaction terminates to obtain mitolactol solution；Mitolactol solution left at room temperature 20 hours, filters, obtains mitolactol coarse crystallization；Mitolactol coarse crystallization adds the methanol of 100 times of coarse crystallization weight, recrystallization at 7 DEG C, obtains mitolactol.
Experimental result: mitolactol average yield 33%, average purity is 62%.
Process ration is tested:
Experimental technique: according to reaction pressure disclosed by the invention, reaction temperature and hydrobromic acid solution concentration, prepares embodiment 1-8 sample；Want, on the preparation method basis of embodiment 1-8, to deduct the reaction condition of pressurization, prepare comparative example 1-6 sample respectively.Yield and purity result are in Table 1.
Yield computational methods:
Table 1 yield and purity testing result
Table 1 result shows: the operating procedure of comparative example 1-6 corresponding embodiment 1-8 respectively, only deduct compressive reaction condition, the yield of dibromo hexanhexol has significant difference with purity compared with pressurization, and average yield is between the 59-73% of embodiment, and average purity is between the 70-76% of embodiment.
Test result indicate that: by response parameter provided by the invention, it is possible to obtain being substantially better than existing technical scheme and prepare the effect of gained dibromo hexanhexol.
Although, above use generality explanation, detailed description of the invention and test, the present invention is described in detail, but on basis of the present invention, it is possible to it is made some modifications or improvements, and this will be apparent to those skilled in the art.Therefore, these modifications or improvements without departing from theon the basis of the spirit of the present invention, belong to the scope of protection of present invention.
Claims (15)
1. a preparation method for dibromo hexanhexol, including bromination step, it is characterised in that: hexanhexol bromination process course of reaction carries out under elevated pressure.
2. preparation method as claimed in claim 1, it is characterised in that: described being pressurised into passes into the pressurization of gas fixation pressure or gradient type pressurization.
3. preparation method as claimed in claim 2, it is characterised in that: described gas is be not involved in reaction and the gas that will not reaction be had undesirable effect.
4. preparation method according to claim 3, it is characterised in that: described gas is noble gas, carbon dioxide or helium.
5. preparation method as claimed in claim 2, it is characterised in that: described fixation pressure pressurizes, and pressure limit is 0.1-3.0Mpa.
6. preparation method as claimed in claim 2, it is characterised in that: described gradient type pressurizes, and pressure is not less than 0.5Mpa when reaction terminates.
7. preparation method as claimed in claim 1, it is characterised in that: described hexanhexol is mannitol, dulcitol, sorbitol.
8. preparation method as claimed in claim 1, it is characterised in that described bromination process comprises the steps:
Take hexanhexol and put in reaction vessel, add hydrobromic acid solution, reacting by heating 2-24 hour, heating-up temperature is 30-90 DEG C, in the response time of 2-24 hour, pressure is started to step up by 0Mpa, until being finally not less than 0.5Mpa, being stirred continuously during reaction, reaction terminates and obtains dibromo hexanhexol solution.
9. preparation method as claimed in claim 8, it is characterised in that temperature during described reaction is 40-80 DEG C.
10. preparation method as claimed in claim 8, it is characterised in that temperature during described reaction is 70 DEG C.
11. preparation method as claimed in claim 8, it is characterised in that described hydrobromic acid solution concentration is 20-80%.
12. preparation method as claimed in claim 8, it is characterised in that described hydrobromic acid solution concentration is 30-62%.
13. preparation method as claimed in claim 8, it is characterised in that described hydrobromic acid solution concentration is 40%.
14. the preparation method as described in any one of claim 11-13, it is characterised in that 2-15 times that amount is hexanhexol weight of described hydrobromic acid solution.
15. preparation method as claimed in claim 1, it is characterised in that comprise the steps:
1) take hexanhexol and put in reaction vessel, add hexanhexol weight 2-15 times, concentration is the hydrobromic acid solution of 20-80%, reacting by heating 2-24 hour, heating-up temperature was 30-90 DEG C, and heating is to 30-90 DEG C, the response time of 2-24 hour, in the response time of 2-24 hour, pressure is started to step up by 0Mpa, until being finally not less than 0.5Mpa, being stirred continuously during reaction, reaction terminates and obtains dibromo hexanhexol solution；
2) dibromo hexanhexol solution left at room temperature more than 12 hours, filters, obtains dibromo hexanhexol coarse crystallization；
3) dibromo hexanhexol coarse crystallization recrystallizing methanol, obtains dibromo hexanhexol.
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| US20080107598A1 (en) * | 2006-10-05 | 2008-05-08 | Yang David J | Efficient Synthesis of Chelators for Nuclear Imaging and Radiotherapy: Compositions and Applications |
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| US20080107598A1 (en) * | 2006-10-05 | 2008-05-08 | Yang David J | Efficient Synthesis of Chelators for Nuclear Imaging and Radiotherapy: Compositions and Applications |
| CN103270035A (en) * | 2010-08-18 | 2013-08-28 | 德玛医药 | Method of synthesis of substituted hexitols such as dianhydrogalactitol |
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