CN107915755A - A kind of Methylethyl diethoxy silane synthetic method - Google Patents
A kind of Methylethyl diethoxy silane synthetic method Download PDFInfo
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- CN107915755A CN107915755A CN201711072213.5A CN201711072213A CN107915755A CN 107915755 A CN107915755 A CN 107915755A CN 201711072213 A CN201711072213 A CN 201711072213A CN 107915755 A CN107915755 A CN 107915755A
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- diethoxy silane
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- synthetic method
- sodium
- methylethyl
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- C—CHEMISTRY; METALLURGY
- C07—ORGANIC CHEMISTRY
- C07F—ACYCLIC, CARBOCYCLIC OR HETEROCYCLIC COMPOUNDS CONTAINING ELEMENTS OTHER THAN CARBON, HYDROGEN, HALOGEN, OXYGEN, NITROGEN, SULFUR, SELENIUM OR TELLURIUM
- 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
- C07F7/18—Compounds having one or more C—Si linkages as well as one or more C—O—Si linkages
- C07F7/1804—Compounds having Si-O-C linkages
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- C—CHEMISTRY; METALLURGY
- C07—ORGANIC CHEMISTRY
- C07F—ACYCLIC, CARBOCYCLIC OR HETEROCYCLIC COMPOUNDS CONTAINING ELEMENTS OTHER THAN CARBON, HYDROGEN, HALOGEN, OXYGEN, NITROGEN, SULFUR, SELENIUM OR TELLURIUM
- 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
- C07F7/18—Compounds having one or more C—Si linkages as well as one or more C—O—Si linkages
- C07F7/1804—Compounds having Si-O-C linkages
- C07F7/1872—Preparation; Treatments not provided for in C07F7/20
- C07F7/1876—Preparation; Treatments not provided for in C07F7/20 by reactions involving the formation of Si-C linkages
Abstract
The present invention relates to a kind of Methylethyl diethoxy silane synthetic method, including step are as follows：Directly using methyltriethoxysilane as solvent and reaction raw materials, metallic sodium is dispersed in methyltriethoxysilane, forms sodium sand, condensation reaction then occurs with bromoethane, obtains Methylethyl diethoxy silane.The present invention is in product is by prepared by sodium condensation method building-up process without using extra solvent, directly sodium sand is prepared using reaction raw materials methyltriethoxysilane as solvent, reaction condition is gentle, technique is simple, with flow pump raw material bromoethane is added from reactor bottom, make the high conversion rate of the relatively low bromoethane of boiling point, target product content is high, good product selectivity and consersion unit utilization rate height.
Description
Technical field
The present invention relates to organic chemistry filed, is specifically a kind of compounds methyl ethyl diethoxy silane containing element silicon
Synthetic method.
Background technology
High low temperature resistant organosilicon sealant can be widely applied to aerospace, satellite sun energy, nuclear industry, telecommunications,
It is with good economic efficiency in psychro-environment in the multiple fields such as chemical industry, medicine, ship, submarine, battleship, bullet train
And promotional value, and the key raw material for preparing high low temperature resistant organosilicon sealant is ethyl organic silicon monomer, at present state's interior energy
It is considerably less to synthesize the enterprise of ethyl monomer, and the price is very expensive, limits the use of this elite clone, therefore, synthesizes into
This relatively low ethyl organic silicon monomer is very necessary.
Chinese patent document CN1569859A (application numbers：200410018068.9) disclose a kind of ethyl trimethyl silane
Synthetic method, it is characterized in that being the mixed of solvent or this ether and aromatic hydrocarbon with higher boiling ethers R-O- (CH2CH2-O) n-R (I)
Compound is solvent, and under iodine initiation, jesse greener reagent ethyl halogenation is made with metal reactive magnesium in ethyl halide CH3CH2X (II)
Magnesium solution, then trim,ethylchlorosilane is added in ethyl magnesium halide solution and carries out ethylation reaction, divided after reaction
Evaporate obtained ethyl trimethyl silane.The above method will not only use substantial amounts of solvent, add Material Cost and solvent recovery into
This, and grignard reagent and chlorosilane have been used, this requires the stringent anhydrous and oxygen-free of production process, to production equipment and process
It is required that it is very high, and there is certain danger, in addition, this method technique is cumbersome, production procedure length, inefficiency, discomfort
Close large-scale industrial production.
Organo-silicon compound based on sodium contracting method synthesizing new are it has been reported that for example：Chinese patent document CN
102898459A (application numbers：201210222070.2) a kind of preparation method of diethyldimethoxysilane is disclosed, it is described
Diethyldimethoxysilane using ethyl trimethoxy silane and bromoethane as raw material, be made up of prepared by sodium condensation method, this method
The controllability of reaction is improved, reaction condition is gentle, and technique is simple；The choosing of diethyldimethoxysilane in synthetic mixture
Selecting property is good, and yield is higher, is suitable for large-scale industrial production.Can be introduced some special functional groups using prepared by sodium condensation method is had
In machine silicon molecule, and cost is more cheap.However, method disclosed in the patent document uses toluene as solvent, it is necessary to face
Face serious environmental pollution and recycled solvent problem, the conversion ratio of raw material bromoethane is relatively low.
The content of the invention
In view of the deficiencies of the prior art, the present invention provides a kind of Methylethyl diethoxy silane synthetic method.
Present invention solves the technical problem that it is：The combined coefficient and yield of existing Methylethyl diethoxy silane are low；
And in prepared by sodium condensation method synthesizing methyl ethyl diethoxy silane, using toluene equal solvent, the environmental pollution brought and solvent are not
The problem of easily recycling.
Technical scheme is as follows：
A kind of Methylethyl diethoxy silane synthetic method, including step are as follows：
Directly using methyltriethoxysilane as solvent and reaction raw materials, metallic sodium is dispersed in methyltriethoxy silane
In alkane, sodium sand is formed, condensation reaction then occurs with bromoethane, obtains Methylethyl diethoxy silane.
, according to the invention it is preferred to, the Methylethyl diethoxy silane synthetic method, including step are as follows：
(1) methyltriethoxysilane is stirred and heated up, add metallic sodium under continuous stirring, metallic sodium is made in stirring
Sodium sand is broken under；
(2) bromoethane is added, keeps reaction mixture back flow reaction and controlling reaction temperature≤112 DEG C；
(3) after reaction, reaction mixture is cooled down, is then added dropwise in ethanol and excessive metallic sodium and remains anti-
Should, then the sodium alkoxide in methylchlorosilane and generated is added dropwise；Then, separation of solid and liquid removes the solid impurity in reaction mixture, together
When collect filtrate；
(4) separating-purifying is carried out to filtrate, obtains Methylethyl diethoxy silane.
, according to the invention it is preferred to, methyltriethoxysilane stirs and is warming up to 90~112 DEG C in step (1), further
Preferably 102~105 DEG C；
Preferably, methyltriethoxysilane and the molar ratio of metallic sodium are (4~6)：1.
, according to the invention it is preferred to, the addition control of bromoethane is bromoethane in step (2)：Methyltriethoxy silane
The molar ratio of alkane is 1：(1~2), further preferred (1.5~2)；
Preferably, reflux time is 0.1~20h, more preferably 2~10h.
, according to the invention it is preferred to, the reaction temperature in step (3) in ethanol with metallic sodium is 0~50 DEG C, further excellent
Elect 15~35 DEG C as；Reaction time is 0.1~4h, more preferably 0.5~2h；
Preferably, the time for adding of ethanol is 0.05~2h, more preferably 0.1~1h.
, according to the invention it is preferred to, the methylchlorosilane described in step (3) is methyl trichlorosilane, dimethyl dichloro
Silane or methyl trichlorosilane, further preferred methyl trichlorosilane；
Preferably, ethanol：The molar ratio of metallic sodium is 10：1.
, according to the invention it is preferred to, described in step (3) in methylchlorosilane and in sodium ethoxide reaction, methylchlorosilane
Time for adding be 0.1~4h；More preferably 0.5~2h；The reaction is held time preferably 1~8h, and particularly preferably 2
~6h.
, according to the invention it is preferred to, the mode of the separating-purifying described in step (4) is rectifying.
The present invention, using new process, passes through prepared by sodium condensation method using methyltriethoxysilane and bromoethane as raw material
Prepare Methylethyl diethoxy silane [MeEtSi (OEt)2], join by varying raw material proportioning, feed rate, reaction temperature etc.
Number, further improves target product yield.
The structural formula of the synthetic product Methylethyl diethoxy silane of the present invention is as follows：
Shown in reaction equation of the present invention such as formula (I)：
The solventless method that the present invention uses does not have serious side reaction, and is really due to making solvent with reactant
A kind of concentration of reactant is improved, reaction balance can be made to accelerate the direction to production product, therefore, production efficiency can be improved,
It is highly effective to control cost in production.
The invention has the advantages that：
1. in reaction process in addition to reaction raw materials bromoethane and methyltriethoxysilane, without using other solvents, instead
Mild condition is answered, technique is simple；
2. the ring faced in organic compound technique using toluene solvant is prepared the present invention overcomes traditional prepared by sodium condensation method
Border is polluted and recycled solvent problem, is effectively improved consersion unit utilization rate, improves the conversion ratio of raw material bromoethane.
The single transformation rate of bromoethane is up to 78%.
3. Methylethyl diethoxy silane content is high in synthetic mixture of the present invention, target product Methylethyl diethoxy
For the yield of base silane up to 32%, target product Methylethyl diethoxy silane separating-purifying is simple, can significantly save behaviour
Make expense, be very suitable for large-scale industrial production.
Embodiment
Below by specific embodiment, the invention will be further described, but not limited to this.
Embodiment 1
In the drying 250mL four-hole boiling flasks equipped with reflux condensing tube, mechanical agitator and Pt-100 platinum resistance, add
109g methyltriethoxysilane, adds the sodium piece of 15g fresh cuts, is warming up to 102 DEG C, sodium piece is broken into sodium sand under agitation；
In 4h, 84g bromoethanes are added slowly in reaction system by flow pump from reactor bottom, and recycle condensate.Control is anti-
Temperature is answered between 108~110 DEG C, the reaction was continued 2h after being added dropwise, after being cooled to 25 DEG C, is slowly added into 1.5g in 0.5h
With excessive metallic sodium in absolute ethyl alcohol, 1h is maintained at 25 DEG C again after being added dropwise；Then by 12.7mL methyl trichlorosilanes
It is added drop-wise in 1h in mixture, to neutralize the sodium alkoxide of generation；After being added dropwise, then the reaction was continued at such a temperature 3h.Then
Reaction mixture is depressurized and is filtered, obtains diethoxy silane containing Methylethyl, diethylmethyl Ethoxysilane, three second of methyl
The mixture that oxysilane and a small amount of polycondensation product are formed.
Mixture is subjected to rectifying, obtains Methylethyl diethoxy silane, the yield of Methylethyl diethoxy silane
For 31%, purity 99.5%；The conversion ratio of bromoethane is 71%.
Embodiment 2
In the drying 1000mL four-hole boiling flasks equipped with reflux condensing tube, mechanical agitator and Pt-100 platinum resistance, add
560g methyltriethoxysilane, adds the sodium piece of 56.2g fresh cuts, is warming up to 105 DEG C, sodium piece is broken into sodium sand under agitation；
In 2h, 214g bromoethanes are added slowly in reaction system by flow pump from reactor bottom, and recycle condensate, are controlled
Between 102~105 DEG C, the reaction was continued 4h after being added dropwise, after being cooled to 30 DEG C, is slowly added into reaction temperature in 1.0h
With excessive metallic sodium in 5.1g absolute ethyl alcohols, 1.5h is maintained at 30 DEG C again after being added dropwise；Then by 47.5mL methyl three
Chlorosilane is added drop-wise in mixture in 2h, to neutralize the sodium alkoxide of generation；After being added dropwise, then the reaction was continued at such a temperature
4h.Then by reaction mixture depressurize filter, obtain diethoxy silane containing Methylethyl, diethylmethyl Ethoxysilane,
The mixture that methyltriethoxysilane and a small amount of polycondensation product are formed.
Mixture is subjected to rectifying, obtains Methylethyl diethoxy silane, the yield of Methylethyl diethoxy silane
For 25%, purity 99.5%；The conversion ratio of bromoethane is 73%.
Embodiment 3
In the drying 500mL four-hole boiling flasks equipped with reflux condensing tube, mechanical agitator and Pt-100 platinum resistance, add
320g methyltriethoxysilane, adds the sodium piece of 20g fresh cuts, is warming up to 104 DEG C, sodium piece is broken into sodium sand under agitation；
In 6h, 87g bromoethanes are added slowly in reaction system by flow pump from reactor bottom, and recycle condensate, control is anti-
Temperature is answered between 105~108 DEG C, the reaction was continued 5h after being added dropwise, after being cooled to 20 DEG C, is slowly added into 2.0g in 1.0h
With excessive metallic sodium in absolute ethyl alcohol, 1.5h is maintained at 20 DEG C again after being added dropwise；Then by 22mL dimethyl dichloro silicon
Alkane is added drop-wise in mixture in 1.5h, to neutralize the sodium alkoxide of generation；After being added dropwise, then the reaction was continued at such a temperature 2h.
Then reaction mixture is depressurized and filtered, obtain diethoxy silane containing Methylethyl, diethylmethyl Ethoxysilane, methyl
The mixture that triethoxysilane and a small amount of polycondensation product are formed.
Mixture is subjected to rectifying, obtains Methylethyl diethoxy silane, the yield of Methylethyl diethoxy silane
For 29%, purity 99.5%；The conversion ratio of bromoethane is 74%.
Embodiment 4
In the drying 500mL four-hole boiling flasks equipped with reflux condensing tube, mechanical agitator and Pt-100 platinum resistance, add
344g methyltriethoxysilane, adds the sodium piece of 25g fresh cuts, is warming up to 105 DEG C, sodium piece is broken into sodium sand under agitation；
In 4h, 92g bromoethanes are added slowly in reaction system by flow pump from reactor bottom, and recycle condensate, control is anti-
Temperature is answered between 102~104 DEG C, the reaction was continued 2h after being added dropwise, after being cooled to 20 DEG C, is slowly added into 2.0g in 1.0h
With excessive metallic sodium in absolute ethyl alcohol, 1.5h is maintained at 20 DEG C again after being added dropwise；Then by 21.2mL methyl trichlorine silicon
Alkane is added drop-wise in mixture in 2h, to neutralize the sodium alkoxide of generation；After being added dropwise, then the reaction was continued at such a temperature 6h.So
Reaction mixture is depressurized afterwards and is filtered, obtains diethoxy silane containing Methylethyl, diethylmethyl Ethoxysilane, methyl three
The mixture that Ethoxysilane and a small amount of polycondensation product are formed.
Mixture is subjected to rectifying, obtains Methylethyl diethoxy silane, the yield of Methylethyl diethoxy silane
For 24%, purity 99.5%；The conversion ratio of bromoethane is 78%.
By 4 gained 4g Methylethyls diethoxy silane of embodiment through column chromatography for separation, the interior filling column chromatography of chromatographic column
Silica gel, with petroleum ether：Ethyl acetate is 5:1 mixed liquor is eluent, obtains the Methylethyl diethoxy silane of high-purity,
Carried out respectively FT-IR,1H NMR and13C NMR are analyzed, to determine and verify the structure of target compound.
Nuclear magnetic data is as follows：
1H-NMR (CDCl3,400MHz) δ：1.325-1.360 (t, 3H, OCH2CH3), 3.860-3.936 (t, 2H,
OCH2CH3), 0.51 (q, 2H, CH2)；
13C-NMR (CDCl3,400MHz) δ：58.4,22.4,18.4,8.92,6.48, -1.36, -3.2.
Infrared data is as follows：
IR(KBr)ν:2973 (CH3), 1104,1165 (Si-OEt), 1258 (Si-Me), 239,1009,956 (Si-Et).
Comparative example 1
As described in Example 4, unlike：
300mL toluene is added as solvent, the yield of Methylethyl diethoxy silane is 17%, the conversion ratio of bromoethane
For 81%.Although conversion ratio increases, yield declines to a great extent, and greatly reduces production efficiency, and toluene is easier
Steamed with the bromoethane steamed, increase later stage separation costs.
Claims (10)
1. a kind of Methylethyl diethoxy silane synthetic method, including step are as follows：
Directly using methyltriethoxysilane as solvent and reaction raw materials, metallic sodium is dispersed in methyltriethoxysilane
In, sodium sand is formed, condensation reaction then occurs with bromoethane, obtains Methylethyl diethoxy silane.
2. Methylethyl diethoxy silane synthetic method according to claim 1, it is characterised in that including step such as
Under：
(1) methyltriethoxysilane is stirred and heated up, add metallic sodium under continuous stirring, by metallic sodium under stirring
Break into sodium sand；
(2) bromoethane is added, keeps reaction mixture back flow reaction and controlling reaction temperature≤112 DEG C；
(3) after reaction, reaction mixture is cooled down, is then added dropwise in ethanol and excessive metallic sodium and maintains to react, then
The sodium alkoxide in methylchlorosilane and generated is added dropwise；Then, separation of solid and liquid removes the solid impurity in reaction mixture, collects at the same time
Filtrate；
(4) separating-purifying is carried out to filtrate, obtains Methylethyl diethoxy silane.
3. Methylethyl diethoxy silane synthetic method according to claim 2, it is characterised in that first in step (1)
The stirring of ethyl triethoxy silicane alkane is warming up to 90~112 DEG C, is preferably 102~105 DEG C.
4. Methylethyl diethoxy silane synthetic method according to claim 2, it is characterised in that first in step (1)
The molar ratio of ethyl triethoxy silicane alkane and metallic sodium is (4~6)：1.
5. Methylethyl diethoxy silane synthetic method according to claim 2, it is characterised in that bromine in step (2)
The addition control of ethane is bromoethane：The molar ratio of methyltriethoxysilane is 1：(1~2).
6. Methylethyl diethoxy silane synthetic method according to claim 2, it is characterised in that returned in step (2)
The stream reaction time is 0.1~20h, is preferably 2~10h.
7. Methylethyl diethoxy silane synthetic method according to claim 2, it is characterised in that second in step (3)
In alcohol and metallic sodium reaction temperature be 0~50 DEG C, be preferably 15~35 DEG C；
Reaction time is 0.1~4h, is preferably 0.5~2h；
Preferably, the time for adding of ethanol is 0.05~2h.
8. Methylethyl diethoxy silane synthetic method according to claim 2, it is characterised in that institute in step (3)
The methylchlorosilane stated is methyl trichlorosilane, dimethyldichlorosilane or methyl trichlorosilane；
Preferably, ethanol：The molar ratio of metallic sodium is 10：1.
9. Methylethyl diethoxy silane synthetic method according to claim 2, it is characterised in that institute in step (3)
State with sodium ethoxide reaction in methylchlorosilane, the time for adding of methylchlorosilane is 0.1~4h；The reaction is held time as 1
~8h.
10. Methylethyl diethoxy silane synthetic method according to claim 2, it is characterised in that institute in step (4)
The mode for the separating-purifying stated is rectifying.
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Citations (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN102898456A (en) * | 2012-03-21 | 2013-01-30 | 杭州师范大学 | O-benzyldiethoxymethylsilane and preparation method thereof |
| CN102898455A (en) * | 2012-03-21 | 2013-01-30 | 杭州师范大学 | P-benzyldiethoxymethylsilane and preparation method thereof |
| CN102898454A (en) * | 2012-03-21 | 2013-01-30 | 杭州师范大学 | M-methylphenyldiethoxymethylsilane and preparation method thereof |
-
2017
- 2017-11-03 CN CN201711072213.5A patent/CN107915755A/en active Pending
Patent Citations (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN102898456A (en) * | 2012-03-21 | 2013-01-30 | 杭州师范大学 | O-benzyldiethoxymethylsilane and preparation method thereof |
| CN102898455A (en) * | 2012-03-21 | 2013-01-30 | 杭州师范大学 | P-benzyldiethoxymethylsilane and preparation method thereof |
| CN102898454A (en) * | 2012-03-21 | 2013-01-30 | 杭州师范大学 | M-methylphenyldiethoxymethylsilane and preparation method thereof |
Non-Patent Citations (1)
| Title |
|---|
| 伟明: "乙烯基特种有机硅单体和中间体的生产", 《有机硅材料及应用》 * |
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Application publication date: 20180417 |