CN109232632A - A kind of preparation method of two silicon urea of hexamethyl - Google Patents
A kind of preparation method of two silicon urea of hexamethyl Download PDFInfo
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- CN109232632A CN109232632A CN201811216086.6A CN201811216086A CN109232632A CN 109232632 A CN109232632 A CN 109232632A CN 201811216086 A CN201811216086 A CN 201811216086A CN 109232632 A CN109232632 A CN 109232632A
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- urea
- hexamethyl
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- hexamethyldisilazane
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- C07—ORGANIC CHEMISTRY
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- C07F7/00—Compounds containing elements of Groups 4 or 14 of the Periodic System
- C07F7/02—Silicon compounds
- C07F7/08—Compounds having one or more C—Si linkages
- C07F7/10—Compounds having one or more C—Si linkages containing nitrogen having a Si-N linkage
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Abstract
A kind of preparation method of two silicon urea of hexamethyl, described method includes following steps: in the presence of an inert gas, in the reactor, glycol dimethyl ether is first added, hexamethyldisilazane is then added, adds urea, and catalyst ammonium chloride or ammonium sulfate, it is warming up at 70-90 DEG C and is reacted, reaction time 30-40 minute, at this time ammonia evolution terminates.Reactant is cooled to room temperature, is filtered, is recycled the two silicon urea of hexamethyl of precipitating, be then dried under reduced pressure, obtain two silicon urea of hexamethyl.Filtrate set is collected in the production of next batch.Method of the invention has the reaction time short, and solvent usage is few, the high advantage of product stability.
Description
Invention field
The present invention relates to a kind of preparation methods of silylating reagent, more particularly to a kind of preparation side of two silicon urea of hexamethyl
Method.
Background technique
Two silicon urea of hexamethyl also known as double-trimethyl silicane urea (BSU) are a kind of excellent silylating reagents, can be by organic matter
Reactive hydrogen atom (- OH ,-COOH ,-NH ,-SH) replaces with trimethyl silane group in molecule, and is formed and elimination reaction item
Part is mild, substantially can quantitatively carry out.It is wide due to can be improved after silanization protection by the stability of protection compound
It is general to be applied to organic synthesis and medical industry, it is indispensable in the semisynthetic antibiotics synthesis developed rapidly in recent years
Radical protection agent has biggish industrial production value.Two silicon urea of hexamethyl is most managed in beta-lactam antibiotic synthesis
The silane protectant thought.It by taking cephalo IV is semi-synthetic as an example, only participating in reacting with BSU, reaction can be made extremely mild, side reaction is few,
Yield improves 2-3 times than other methods.There is great practical value in the industrial production of current antibiotic.
For the synthesis technology of two silicon urea of hexamethyl, mainly using hexamethyldisilazane, urea catalyst presence
Lower reaction and prepare, wherein used catalyst has ammonium salt such as ammonium chloride, ammonium sulfate (US3992428), Lewis acid for example
Such as BCl3、TICl4、AlCl3, inorganic acid such as HCl, HBr, H2SO4、H3PO4, acid salt etc. (such as CN101665507), contain
The nitrogen compound of electron-withdrawing group such as saccharin (EP43630), trim,ethylchlorosilane (chemistry world, the 10th phase, 1998,
522-524 pages).Although these catalyst can shorten the reaction time, their major defect is that it can remain in product
In BSU, the unstability for causing product BSU to store, to reduce them for the repellence that hydrolyzes and change colour.Due to these
Disadvantage limits it in the application of certain industrial circles, especially to the demanding pharmaceutical industries of impurity, is especially preparing
Application in antibiotic.
Solvent can be used in the synthesis for the two silicon urea of hexamethyl mentioned in document, solvent can also not used.It is most of
Method in used solvent, such as benzene, toluene, ethyl acetate, ethers such as tetrahydrofuran etc., acetone, methylene chloride, 1,2-
Dichloroethanes, hexamethyldisiloxane (see, for example, US3992428, EP43630), nitrile solvents such as acetonitrile
(CN1288894).
But the above method has following defects that (1) for the preparation method without using solvent, needs to require hexamethyl
Disilazane (HMDZ) excessively, generally requires excessively 3 times or more, but due to the price of HMDZ height, when needs use excessively very
More HMDZ will will lead to production cost raising, although existing technology, which gives, can be recycled HMDZ, due to miscellaneous
The continuous accumulation of matter, causes its cycle-index limited, still results in the increase of production cost.(2) for using the system of solvent
Preparation Method, the selection meeting large effect reaction time of solvent, and after completion of the reaction, it needs to handle filtrate, meeting
Increase the production time.In addition, the usage amount of solvent is bigger than normal in existing technology, such as need the molten of stoichiometric ratio 2 times or more
Agent, so that increased production cost.(3) for the use of catalyst, since it can be remained in the product, to influence the storage of product
Deposit stability.
Therefore, there is still a need for seek the method for solving the two silicon urea of preparation hexamethyl of drawbacks described above, it is molten so as to reduce
The dosage of agent, reduction catalyst is remaining in the product, improves the preparation method of the stability of storage.
Summary of the invention
The object of the present invention is to provide a kind of preparation method for preparing two silicon urea of hexamethyl, the method can reduce solvent
Usage amount, shorten the reaction time, avoid the residual of catalyst in the product.
By inventor's the study found that foregoing invention purpose can be realized by the following technical solutions.
The present invention provides a kind of preparation methods of two silicon urea of hexamethyl, and described method includes following steps:
In the presence of an inert gas, in the reactor, glycol dimethyl ether is first added, hexamethyldisilazane is then added, then
Urea and catalyst ammonium chloride or ammonium sulfate is added, is warming up at 70-90 DEG C and is reacted, reaction time 30-40 point
Clock, at this time ammonia evolution terminate.Reactant is cooled to room temperature, is filtered, is recycled the two silicon urea of hexamethyl of precipitating, then depressurizing
Lower drying obtains two silicon urea of hexamethyl.It is spare to collect filtrate.
The present invention is carried out under inert atmosphere under normal pressure, and the inert gas is selected from nitrogen or argon gas.Wherein, pregnancy
Base disilazane: the molar ratio of urea is 1:1.0-1.4, preferably 1:1.1-1.2.
The present invention uses solvent ethylene glycol dimethyl ether, and the molar ratio of glycol dimethyl ether and hexamethyldisilazane is 1-2:
1, preferably 1.2-1.8:1.
Catalyst ammonium chloride or the dosage of ammonium sulfate are 1ppm-40ppm, preferably 5-25ppm in the present invention.
In the method for the invention, the filtrate of collection is used for the production of the two silicon urea of hexamethyl of next batch.
According to the method for the present invention, reaction temperature is preferably 80-90 DEG C.
The present inventor has found after study, when use glycol dimethyl ether as solvent, ammonium chloride or ammonium sulfate
As catalyst, by being used cooperatively for solvent and special catalyst, due to catalyst glycol dimethyl ether solubility with
The difference of solubility in the product is obvious, so that after the completion of reaction, catalyst ammonium chloride, ammonium sulfate can be retained in filtrate
In, and hardly remain in the product, the purity of product can be significantly improved in this way.To two silicon urea of resulting product hexamethyl
Stability experiment has been carried out, the experimental results showed that the product passes through storage in 6 months, still there is good stable storing
Property.In addition, inventor also found, when the system using glycol dimethyl ether and ammonium chloride, ammonium sulfate, can also further decrease
Reaction time, reaction only need can be completed for 30-40 minutes.At the same time, use glycol dimethyl ether as solvent, solvent makes
Dosage also obtains a degree of reduction, to reduce use cost.
Compared with existing technology, the invention has the following advantages that
1, the reaction time of the invention is shorter, shortens reaction process.The quantity of solvent used is lower, can be greatly reduced and be produced into
This.
2, production can be improved to avoid the residual of catalyst ammonium chloride, ammonium sulfate in the product using method of the invention
The purity of product, and product can be stabilized up to 6 months or more.
Specific embodiment
Below with reference to embodiment, the present invention will be described in detail, it should be understood that its purpose is merely exemplary, rather than is anticipated
The protection scope of claims to be limited.
Embodiment 1
Under nitrogen protection, with stirring, be packed into 520ml(5mol in the reactor) glycol dimethyl ether, 807g(5mol)
Hexamethyldisilazane, 300g(5mol) urea, the ammonium chloride of 5ppm reacts at 70 DEG C, after nitrogen evolution
Stop reaction, the reaction time is 30 minutes.Reactant is cooling, and filter cake is dried under reduced pressure, obtains 1014g's by filtering
Two silicon urea of product hexamethyl, yield 99.2%, purity 99.85%.Through detecting, ammonium chloride is not contained in product.It is standby to collect filtrate
With.
Embodiment 2
Under nitrogen protection, with stirring, be packed into 1040ml(10mol in the reactor) glycol dimethyl ether, 807g
The hexamethyldisilazane of (5mol), 300g(5mol) urea, the ammonium chloride of 10ppm reacts at 80 DEG C, when nitrogen escapes
After stop reaction, the reaction time be 35 minutes.Reactant is cooling, and filter cake is dried under reduced pressure, obtains by filtering
The two silicon urea of product hexamethyl of 1016g, yield 99.3%, purity 99.82%.Through detecting, ammonium chloride is not contained in product.It collects
Filtrate is spare.
Embodiment 3
Under nitrogen protection, with stirring, be packed into 624ml(6mol in the reactor) glycol dimethyl ether, 1130g
The hexamethyldisilazane of (7mol), 300g(5mol) urea, the ammonium chloride of 25ppm reacts at 90 DEG C, when nitrogen escapes
After stop reaction, the reaction time be 40 minutes.Reactant is cooling, and filter cake is dried under reduced pressure, obtains by filtering
The two silicon urea of product hexamethyl of 1017g, yield 99.4%, purity 99.79%.Through detecting, ammonium chloride is not contained in product.It collects
Filtrate is spare.
Embodiment 4
Under nitrogen protection, with stirring, be packed into 624ml(6mol in the reactor) glycol dimethyl ether, 968g(6mol)
Hexamethyldisilazane, 300g(5mol) urea, the ammonium chloride of 40ppm reacts at 90 DEG C, after nitrogen evolution
Stop reaction, the reaction time is 40 minutes.Reactant is cooling, and filter cake is dried under reduced pressure, obtains 1018g's by filtering
Two silicon urea of product hexamethyl, yield 99.5%, purity 99.81%.Through detecting, ammonium chloride is not contained in product.It is standby to collect filtrate
With.
Embodiment 5
Under nitrogen protection, with stirring, be packed into 520ml(5mol in the reactor) glycol dimethyl ether, 807g(5mol)
Hexamethyldisilazane, 300g(5mol) urea, the ammonium sulfate of 5ppm reacts at 70 DEG C, after nitrogen evolution
Stop reaction, the reaction time is 30 minutes.Reactant is cooling, and filter cake is dried under reduced pressure, obtains 1016g's by filtering
Two silicon urea of product hexamethyl, yield 99.3%, purity 99.81%.Through detecting, ammonium sulfate is not contained in product.It is standby to collect filtrate
With.
Embodiment 6
Under nitrogen protection, with stirring, be packed into 1040ml(10mol in the reactor) glycol dimethyl ether, 807g
The hexamethyldisilazane of (5mol), 300g(5mol) urea, the ammonium sulfate of 10ppm reacts at 80 DEG C, when nitrogen escapes
After stop reaction, the reaction time be 37 minutes.Reactant is cooling, and filter cake is dried under reduced pressure, obtains by filtering
The two silicon urea of product hexamethyl of 1017g, yield 99.4%, purity 99.84%.Through detecting, ammonium sulfate is not contained in product.It collects
Filtrate is spare.
Embodiment 7
Under nitrogen protection, with stirring, be packed into 624ml(6mol in the reactor) glycol dimethyl ether, 1130g
The hexamethyldisilazane of (7mol), 300g(5mol) urea, the ammonium sulfate of 25ppm reacts at 90 DEG C, when nitrogen escapes
After stop reaction, the reaction time be 40 minutes.Reactant is cooling, and filter cake is dried under reduced pressure, obtains by filtering
The two silicon urea of product hexamethyl of 1014g, yield 99.2%, purity 99.76%.Through detecting, ammonium sulfate is not contained in product.It collects
Filtrate is spare.
Embodiment 8
Under nitrogen protection, with stirring, be packed into 624ml(6mol in the reactor) glycol dimethyl ether, 968g(6mol)
Hexamethyldisilazane, 300g(5mol) urea, the ammonium sulfate of 40ppm reacts at 90 DEG C, after nitrogen evolution
Stop reaction, the reaction time is 40 minutes.Reactant is cooling, and filter cake is dried under reduced pressure, obtains 1019g's by filtering
Two silicon urea of product hexamethyl, yield 99.7%, purity 99.75%.Through detecting, ammonium sulfate is not contained in product.It is standby to collect filtrate
With.
Embodiment 9
Filtrate applies experiment
Under nitrogen protection, with stirring, it is fitted into 260ml(2.5mol in the reactor) filtrate in embodiment 1,404g
The hexamethyldisilazane of (2.5mol), 150g(2.5mol) urea, the ammonium chloride of 5ppm reacts at 70 DEG C, works as nitrogen
Stop reaction after evolution, the reaction time is 30 minutes.Reactant is cooling, and filter cake is dried under reduced pressure for filtering,
Obtain the two silicon urea of product hexamethyl of 508g, yield 99.3%, purity 99.83%.Collect filtrate, the pregnancy for next batch
The production of two silicon urea of base.The result shows that can apply 20 times, yield and purity without reducing product.
Experiment shows that the filtrate of embodiment 2-8 can equally be applied, and applying number is 19-25 times.
Embodiment 10
Storage stability experiment
The product of embodiment 1-9 is placed into different time, measures the content and activity of two silicon urea of hexamethyl.Experiment shows described
For two silicon urea of hexamethyl when placing 6 months, content stills remain in 98% or more, and activity is also maintained at 98% or more.This shows
After placing 6 months, still there is good storage stability by two silicon urea of hexamethyl prepared by the method for the present invention.
The experimental results showed that the purity of product not only can be improved using method of the invention, but also have good steady
It is qualitative.Further, it is also possible to shorten the reaction time, the usage amount of solvent is reduced, solvent can be recycled, reduce and be produced into
This.
Claims (8)
1. a kind of preparation method of two silicon urea of hexamethyl, includes the following steps:
In the presence of an inert gas, in the reactor, glycol dimethyl ether is first added, hexamethyldisilazane is then added, then
Urea and catalyst ammonium chloride or ammonium sulfate is added, is warming up at 70-90 DEG C and is reacted, reaction time 30-40 point
Clock, at this time ammonia evolution terminate.
2. reactant is cooled to room temperature, filters, recycle the two silicon urea of hexamethyl of precipitating, be then dried under reduced pressure, obtain six
It is spare to collect filtrate for two silicon urea of methyl.
3. according to the method described in claim 1, wherein, the reaction carries out under normal pressure.
4. -2 described in any item methods according to claim 1, wherein hexamethyldisilazane: the molar ratio of urea is 1:
1.0-1.4 preferably 1:1.1-1.2.
5. method according to claim 1-3, wherein mole of glycol dimethyl ether and hexamethyldisilazane
Than for 1-2:1, preferably 1.2-1.8:1.
6. method according to claim 1-4, wherein catalyst ammonium chloride or the dosage of ammonium sulfate are 1ppm-
40ppm, preferably 5-25ppm.
7. method according to claim 1-5, wherein the filtrate of collection is used for the hexamethyl two of next batch
The production of silicon urea.
8. method according to claim 1-6, wherein reaction temperature is preferably 80-90 DEG C.
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| CN201811216086.6A CN109232632B (en) | 2018-10-18 | 2018-10-18 | Preparation method of hexamethyl disilaurea |
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Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN112341475A (en) * | 2020-12-02 | 2021-02-09 | 烟台万润药业有限公司 | Preparation method of clopidogrel hydrogen sulfate |
| CN112480197A (en) * | 2020-12-02 | 2021-03-12 | 新乡拓新药业股份有限公司 | Method for synthesizing cytosine nucleoside |
Citations (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US3992428A (en) * | 1975-02-24 | 1976-11-16 | Wacker-Chemie Gmbh | Process for preparing bis-(trimethylsilyl-)urea |
| US4060536A (en) * | 1975-12-01 | 1977-11-29 | Dynamit Nobel Aktiengesellschaft | Method of preparing N,N'-bis-trimethylsilylurea |
| EP0043630A2 (en) * | 1980-07-04 | 1982-01-13 | Gist-Brocades N.V. | Improved process for the silylation of organic compounds with 1,1,1-trimethyl-N-(trimethylsilyl)silanamine by means of catalysis with certain nitrogen containing compounds |
| CN1288894A (en) * | 1999-06-08 | 2001-03-28 | 阿托菲纳公司 | Process for preparing dimethyl silanyl urea |
| CN101665507A (en) * | 2009-09-08 | 2010-03-10 | 吉林新亚强生物化工有限公司 | Preparation technique of bistrimethylsilurea (BSU) |
-
2018
- 2018-10-18 CN CN201811216086.6A patent/CN109232632B/en active Active
Patent Citations (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US3992428A (en) * | 1975-02-24 | 1976-11-16 | Wacker-Chemie Gmbh | Process for preparing bis-(trimethylsilyl-)urea |
| US4060536A (en) * | 1975-12-01 | 1977-11-29 | Dynamit Nobel Aktiengesellschaft | Method of preparing N,N'-bis-trimethylsilylurea |
| EP0043630A2 (en) * | 1980-07-04 | 1982-01-13 | Gist-Brocades N.V. | Improved process for the silylation of organic compounds with 1,1,1-trimethyl-N-(trimethylsilyl)silanamine by means of catalysis with certain nitrogen containing compounds |
| CN1288894A (en) * | 1999-06-08 | 2001-03-28 | 阿托菲纳公司 | Process for preparing dimethyl silanyl urea |
| CN101665507A (en) * | 2009-09-08 | 2010-03-10 | 吉林新亚强生物化工有限公司 | Preparation technique of bistrimethylsilurea (BSU) |
Cited By (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN112341475A (en) * | 2020-12-02 | 2021-02-09 | 烟台万润药业有限公司 | Preparation method of clopidogrel hydrogen sulfate |
| CN112480197A (en) * | 2020-12-02 | 2021-03-12 | 新乡拓新药业股份有限公司 | Method for synthesizing cytosine nucleoside |
| CN112341475B (en) * | 2020-12-02 | 2023-02-21 | 烟台万润药业有限公司 | Preparation method of clopidogrel hydrogen sulfate |
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Effective date of registration: 20210617 Address after: 223005 No.4, Meicheng Road, higher education park, Huai'an City, Jiangsu Province Applicant after: JIANGSU FOOD & PHARMACEUTICAL SCIENCE College Address before: 100192 room 18, building 18, tower 40, north latitude 40, Chaoyang District 7, Beijing. Applicant before: Ding Chao |
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Application publication date: 20190118 Assignee: Jiangsu Chiatai Qingjiang Pharmaceutical Co.,Ltd. Assignor: JIANGSU FOOD & PHARMACEUTICAL SCIENCE COLLEGE Contract record no.: X2022320000078 Denomination of invention: A preparation method of hexamethyldisilurea Granted publication date: 20210706 License type: Common License Record date: 20220516 |
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