JPH05255352A - Continuous production of oxime silane - Google Patents

Abstract

PURPOSE:To enable continuous production of oximesilane simply and safely, as the formation of explosive oxime hydrochloride is prevented. CONSTITUTION:(a) A silane halide of formula: R<1>4-nSiXn (R<1> is a monovalent hydrocarbon group which may be substituted; X is a halogen atom; n is an integral of 1 to 4), ammonia and an organic solvent in an amount 1 to 20-times the weight of the silane halide are continuously charged into the bottom of the first reactor at the same time. (b) The reaction mixture overflowing from the top of the first reactor is lead to the second reactor, and an oxime of the formula: R<2>R<3>C=N-OH (R<2>, R<3> are H, monovalent hydrocarbon group which may be substituted) is also continuously fed into the second reactor. Then, (c) the reaction mixture from the bottom of the second reactor is led to the slurry tank, and (d) the oximesilane of formula: R<1>4-nSi(ON=CR<2>R<3>)n is recovered therefrom.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for producing oxime silane, and more particularly to a method for easily and safely producing oxime silane by preventing generation of explosive oxime hydrochloride.

[0002]

2. Description of the Related Art Conventionally, oxime silane has been produced by mixing a chlorosilane such as methyltrichlorosilane with a stoichiometrically equivalent amount of an oxime compound, such as methylethylketoxime.
It is carried out by reacting in the presence of a stoichiometrically equivalent amount of an organic base, such as pyridine, as a receptor for hydrochloric acid produced as a by-product during the reaction (see Japanese Patent Publication No. 39-29837).

Further, in the production of this oxime silane, it is also known to react silane chloride with a stoichiometrically double equivalent of the oxime compound (Japanese Patent Publication No. 1-218).
No. 34), in this case, the excess oxime compound acts as an acceptor of hydrochloric acid produced as a by-product during the reaction.

Further, regarding the production of this oxime silane, when reacting a silane chloride with a stoichiometrically equivalent amount of an oxime compound, ammonia as a receiver of hydrochloric acid is stoichiometrically 1.04 to 1.46. A method of continuously producing oxime silane by blowing a double amount has also been proposed (see JP-A-63-227592).

[0005]

However, when hydrochloric acid produced as a by-product in the reaction of silane chloride and an oxime compound is accepted by an organic base such as pyridine, the product is sometimes separated from this organic base hydrochloride by distillation. Risk of explosion. The method of receiving this hydrochloric acid with an excess of oxime compound produces an explosive oxime hydrochloride, and since the oxime compound is expensive, a facility for recovering and purifying the oxime compound from the oxime hydrochloride is required. Further, regarding the method of receiving hydrochloric acid with ammonia, the non-flammable perchlorinated fluorinated alkanes having a boiling point of 60 ° C. or less, especially trichlorotrifluoroethanes, more specifically 1,1,2- Trichlor-1,
Since it is necessary to use a chlorine-based solvent such as 2,2-tolufluoroethane, there are industrial restrictions on the use of the chlorine-based solvent, and there is a problem that its use is difficult. However, there is a disadvantage that the yield is low.

[0006]

SUMMARY OF THE INVENTION The present invention relates to a method for continuously producing oxime silane which solves the above disadvantages and drawbacks, which is represented by the general formula R ¹ _4-n SiX _n (where R ¹
Is an unsubstituted or substituted monovalent hydrocarbon group, X is a halogen atom, n is an integer of 1 to 4), and 1.55n to 1 mol of the halogenated silane.
2. 10 nmole of ammonia and 1 to 20 times by weight of organic solvent are continuously and simultaneously injected into the lower part of the first reactor with respect to the halogenated silane, and (b) continuously from the upper part of the first reactor. At the same time when the reactant flowing out was sent to the second reactor, 1.0n to 1.1n was added to 1 mol of the halogenated silane.
A molar amount of the general formula R ² R ³ C = N-OH (where R ² , R
³ is a hydrogen atom or an oxime compound represented by an unsubstituted or substituted monovalent hydrocarbon group) is continuously injected into the second reactor, and (c) is a reaction product continuously flowing out from the lower part of the second reactor. Is placed in a slurry tank, (d) NH ₄ X precipitate produced as a by-product from the reaction product is removed, and the organic liquid phase is distilled to recover oxime silane.

That is, the present inventors have conducted various studies on a method for obtaining oxime silane safely and in a high yield without danger of explosion. A halogenated silane is used, which is not immediately reacted with the oxime compound, but the halogenated silane is continuously reacted with ammonia, and then the reaction product is continuously reacted with the oxime compound in another reactor. By doing so, it is possible to easily obtain oxime silane without coloring without any danger,
It was found that the yield can be as high as 85% or more, and the present invention was completed by conducting research on this reaction method and the like. This will be described in more detail below.

[0008]

The present invention relates to a continuous method for producing oxime silane, which comprises continuously reacting a halogenated silane with ammonia in an organic solvent and continuously reacting the reaction product with an oxime compound in another reactor. To produce oxime silane.

The halogenated silane used as the starting material in the method of the present invention is represented by the general formula R ¹ _4-n SiX _n , where R ¹ is an alkyl group such as methyl group, ethyl group, propyl group or butyl group, cyclohexyl. Groups such as cycloalkyl groups, vinyl groups, allyl groups, alkenyl groups such as butenyl groups, phenyl groups, aryl groups such as tolyl groups, or some or all of the hydrogen atoms bonded to the carbon atoms of these groups are halogen atoms. An unsubstituted or substituted monovalent hydrocarbon selected from a chloromethyl group and a trifluoropropyl group substituted with, etc., X is a halogen atom such as chlorine and fluorine, and n is 1
Is an integer from 4 to 4, including tetrachlorosilane, trimethylchlorosilane, dimethyldichlorosilane, methyltrichlorosilane, methylethyldichlorosilane, ethyltrichlorosilane, diethyldichlorosilane, triethylchlorosilane, n. -Propyltrichlorosilane, isopropyltrichlorosilane, 2-chloro-
Examples thereof include ethyltrichlorosilane, 3-chloropropyltrichlorosilane, triethylchlorosilane, vinyltrichlorosilane, vinylmethyldichlorosilane, propenyltrichlorosilane, allyltrichlorosilane, phenyltrichlorosilane, and benzyltrichlorosilane, but preferably R ^A trichloro compound in which ¹ is a methyl group, an ethyl group, or a vinyl group is preferable.

When this halogenated silane is reacted with ammonia gas in an organic solvent, Si-X is replaced with Si-NH ₂ or Si-NH-Si (first reaction). Also N
H ₄ X is also a byproduct at the same time. If the amount of ammonia used here is less than 1.55 nmol to 1 mol of halogenated silane, unreacted tends to occur, and if it exceeds 2.10 n, it becomes a large excess, so the range of 1.55 n to 2.10 nmol. And is more preferably 1.60n to 1.9.
It is set to 5 nmol. In addition, the amount of ammonia gas is 1.10 n to 1.45 n based on 1 mol of the halogenated silane by previously absorbing the ammonia gas generated in the second reaction in the organic solvent used in the first reaction. It can be a molar amount.

In the first reaction, in order to reduce the viscosity of the reaction mixture to improve the reactivity and to facilitate the separation of the ammonium halide salt and the oxime silane after the reaction with the oxime compound, which will be described later. , In the presence of organic solvents such as toluene, hexane, petroleum ether, etc. This compounding amount is 1 with respect to halogenated silane.
It is good that the weight is 20 to 20 times, preferably 2 to 10 times.

The reaction temperature in the first reaction is not critical, and the reaction proceeds even at room temperature or lower, and the reaction rate increases with an increase in temperature, but the colorant formation also slightly increases. 0 to 100 ° C, preferably 2
It is set to 5 to 70 ° C. Since the first reaction is an exothermic reaction, it is preferable that the first reactor is a vertical type equipped with a stirrer and has a cooling structure such as a jacket. The residence time of the first reaction may be in the range of 30 seconds to 10 minutes, preferably 1 to 5 minutes.

The reaction product obtained in the first reaction is converted into an oxime silane by the reaction with the oxime compound. The oxime compound used here has the general formula R ² R ³
C = N-OH, and R ² and R ³ are hydrogen atoms or the same unsubstituted or substituted monovalent hydrocarbon group as R ¹ described above, and the hydrocarbon group is particularly methyl. Group, ethyl group, propyl group, butyl group, pentyl group, hexyl group, vinyl group, butenyl group, cyclopentyl group, cyclohexyl group, cyclooctyl group, 3-methyl-1-cyclohexyl group, cyclopentenyl group, phenyl group, tolyl group Examples include groups.

Examples of the oxime compound include 4-methylcyclohexanone oxime, 4-chlorocyclohexanone oxime, acetophenone oxime, benzophenone oxime, benzylethylketone oxime, cyclohexylmethylketone oxime and benzaldehyde oxime. Preferred oxime compounds are formaldehyde. Examples thereof include oximes, acetaldehyde oximes, acetone oximes, methyl ethyl ketone oximes, diethyl ketone oximes, and cyclohexanone oximes, and more preferable examples include methyl ethyl ketone oximes and acetone oximes. The methyl ethyl ketone oximes are room temperature vulcanizing agents for silicone polymers. Most suitable for use in oxime silane compounds used as That.

When the reaction product obtained in the first reaction is reacted with an oxime compound, Si-N = becomes Si- (ON =
It is replaced with CR ² R ³ ) to become oxime silane, and ammonia gas is generated at this time (second reaction). The amount of the oxime compound used here may be in the range of 1.0n to 1.1n mole times, preferably in the range of 1.01n to 1.06n mole times, per mole of the halogenated silane. The addition of the oxime compound may be carried out by dropping in the liquid in the second reactor.

Ammonia generated in the second reactor is a small amount of unreacted halide S which has not been reacted in the first reaction.
It is used as a complement to the halogen of i-X and prevents the formation of oxime halogenate and also prevents the coloration due to Si-X. Ammonia gas generated outside the system from the second reactor is preferably collected by being absorbed by the organic solvent before entering the first reactor.

This reaction temperature is not critical, and it proceeds at room temperature or lower, but the reaction rate increases with increasing temperature, and the formation of colored bodies also slightly increases, so that it is in the range of 0 to 100 ° C. However, preferably 2
The temperature may be in the range of 5 to 75 ° C. Unlike the first reaction described above, this reaction hardly generates heat, so that it is not particularly necessary to cool it. However, the reaction time (in the case of batch method) and the residence time (in the case of continuous method) in this reaction are generally 5 minutes. ~
60 minutes, preferably 10 to 40 minutes,
This may be determined experimentally depending on the type and amount of oxime compound, solvent, temperature and the like.

Oxime silane is produced by the reaction between the first reaction product and the oxime compound (second reaction). In this second reaction product, ammonium halide represented by NH ₄ X is produced as a by-product as a precipitate. As such, it must be separated from the second reactant by filtration. During filtration, it may be washed with an organic solvent to increase the yield. Further, since the liquid phase after this filtration contains an organic solvent, it is necessary to separate the organic solvent by distillation, but since oxime silane becomes markedly colored when heated to 100 ° C. or higher, under reduced pressure, It is preferable to separate at 90 ° C or lower.

The production of oxime silane by the method of the present invention is carried out, for example, by using a halogenated silane and 1 mol of this halogenated silane in an amount of 1.55 n to 2.10 nmole of ammonia and 1 to 20 times the weight of the halogenated silane. Is continuously and simultaneously injected into the lower part of the first reactor to react with each other, and the first reaction product is added to the second reactor from above the first reactor.
Into a reactor, an oxime compound was continuously added in an amount of 1.0 n to 1.1 nmole to 1 mol of a halogenated silane to cause reaction to form an oxime silane, and then NH ₄ X produced as a by-product was filtered off. The phase may be distilled.

Next, this will be described with reference to the accompanying drawings. FIG. 1 shows a preferred embodiment of the oxime silane production apparatus according to the present invention.
The reactor 1 is equipped with a stirrer and has a jacket for cooling. Halogenated silane such as methyltrichlorosilane is injected into the first reactor 1 through a channel 2 in the lower part of the reactor, and an organic solvent such as toluene and hexane having a weight of 2 to 10 times is added to the lower part of the reactor. Channel 3
1.55 n to 2.10 nmole of ammonia gas per 1 mole of halogenated silane is injected from the channel 4 at the bottom of the reactor. When the ammonia gas flowing out from the reactor 2 to be described later is absorbed by the organic solvent before entering the reactor 1, it is 1.
It is sufficient to inject 10 n to 1.15 nmole of ammonia gas.

The reaction is carried out continuously, the residence time is set to 1 to 5 minutes, the generated heat of reaction is cooled by indirect cooling of the reactor, and the reaction temperature is set to 25 to 75 ° C. The first reactant produced by this reaction is continuously sent from the upper part of the reactor to the second reactor 5 through the flow path 6.

An oxime compound is added to the first reaction product sent to the second reactor 5, and oxime silane is synthesized by these reactions. The oxime compound is 1. It suffices to continuously add a molar amount of 0 n to 1.1 n from the channel 7. Ammonia gas flowing out of the system through the flow path 8 can be absorbed by the organic solvent before being injected into the reactor 1.

This reaction may be carried out at a reaction temperature of 25 to 75 ° C. and a residence time of 5 to 60 minutes, preferably 10 to 40 minutes.
The second reaction product is continuously sent to the slurry tank 9 from the flow path 10 at the lower part of the reactor, and then sent to the filter 11 via the flow path 12. By-product ammonium halide is separated from the second reactant by the filter 11. The channel 13 is a solvent channel for cleaning the cake, which is added as necessary.

The solid ammonium halide separated by the filter 11 is removed from the flow path 14, the fluid is sent to the tank 17 through the flow path 16, and then the stripper-1.
It is distilled at 8. After distillation, the oxime silane is obtained as a purified product from the flow path 19, and the vapor stream containing the solvent and the oxime compound is recovered from the flow path 20.

[0025]

EXAMPLES Next, examples of the present invention will be described. Example 1 Vinyl tris (methyl ethyl ketoxime)
Production of silane A vertical columnar reactor 1 having a double tube structure equipped with a Teflon stirrer rotating at 180 rpm and having an inner diameter of 80 mm and a length of 110 mm and capable of cooling the outside with cooling water 1.
At the same time, vinyltrichlorosilane was injected at a rate of 934 g / hour from the flow path 2 below the reactor, and toluene was added at a rate of 5,887.
g / hour (6.3 times the weight of silane) was injected from the flow path 3 below the reactor, and ammonia gas flowed at 700 NL / hour (1.8 × 3 moles per mole of silane) below the reactor. It was injected through the line 4 and reacted at 60 to 75 ° C. for a residence time of 4 minutes.

Then, the reaction product is discharged from the channel 6 to a volume of 10
At the same time as it was made to flow down into the reactor 5 made of Teflon made of L, at the same time, methyl ethyl ketoxime was injected at a rate of 1,555 g / hour (1.03 × 3 mol per mol of silane) from the flow path 7, and the temperature was 60 to 65 ° C. Then, it was transferred from the flow path 10 to the slurry tank 9 with a residence time of 40 minutes. After 5 hours, the reaction was stopped, the reaction product in the slurry tank 9 was sent to the pressure filter 11 through the channel 12 to remove ammonium chloride, and the liquid phase was sent to the tank 15 through the channel 16. The cake thus obtained was washed with toluene and discharged from the flow path 14, and the liquid was sent to the tank 15. Transfer the liquid phase from channel 17 to stripper-18,
Distilled at ˜85 ° C. and below 30 mmHg for 2 hours. When the liquid remaining in the stripper was analyzed by gas chromatography, it was confirmed to be vinyltris (methylethylketoxime) silane having a purity of 95.1%, and the yield based on vinyltrichlorosilane was 93%. ..

Example 2 The same experiment as in Example 1 was repeated, except that the feed rate was vinyltrichlorosilane 1,870 g / hr toluene 9,350 g / hr (5.0 times the weight of the silane) ammonia ( Reactor 1) 1,268 NL / hour (1.63 × 3 moles per mole of silane) Methyl ethyl ketoxime 3,173 g / hour (1.05 × 3 moles per mole of silane) Residence time (reactor 1) = 2.4 minutes When the residence time (reactor 2) was set to 20 minutes, the yield of vinyltris (methylethylketoxime) silane was 91% based on vinyltrichlorosilane.

Example 3 Manufacture of Methyltris (methylethylketoxime) silane It was carried out using the same method and apparatus as described in Example 1, except that methyltrichlorosilane was used instead of vinyltrichlorosilane and the feed rate was Methyltrichlorosilane 1,313 g / hour Toluene 6,171 g / hour (4.7 times the weight of silane) Ammonia (reactor 1) 1,091 NL / hour (1.85 × 3 moles to 1 mole of silane) Methylethylketoxime 2,337 g / hour (1.02 × 3 mol for 1 mol of silane) Residence time (reactor 1) was 3.6 minutes Residence time (reactor 2) was 34 minutes, methyltrichlorosilane to methyltrichlorosilane ( The yield of methylethylketoxime) silane was 9.4%.

[0029]

The present invention relates to a method for producing oxime silane, which comprises reacting a halogenated silane with ammonia in an organic solvent as described above, and reacting the reaction product with an oxime compound in a separate reactor. This is to produce oxime silane. In this case, an explosive oxime halogenate is not generated, so that the oxime silane can be easily and safely obtained. The advantage is given that it can be obtained in high yields above%.

[Brief description of drawings]

FIG. 1 shows a production flow sheet for producing oxime silane according to the present invention.

[Explanation of symbols]

1 First reactor 2, 3, 4, 6, 7, 8, 10, 12, 13, 14, 1
6, 17, 19, 20 Flow path 4 Second reactor 9 Slurry tank 11 Filter 17 Tank 18 Stripper

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Nobuhiko Kotana 2-13-1, Isobe, Annaka-shi, Gunma Shin-Etsu Chemical Co., Ltd. Isobe factory

Claims (3)

[Claims] (A) The general formula R ¹ _4-n SiX _n (where R ¹
Is an unsubstituted or substituted monovalent hydrocarbon group, X is a halogen atom, and n is an integer of 1 to 4), and 1.55n to 1 mol of this halogenated silane is used.
2.1 nmol of ammonia and 1 to 20 times by weight of an organic solvent with respect to this halogenated silane are continuously and simultaneously injected below the first reactor, and (b) continuously from above the first reactor. At the same time as sending outflowing reactants to the second reactor,
Formula 1.0n~1.1n molar amount with respect to the halogenated silane 1 mole ^{R 2 R 3 C = N-} OH ( wherein in R ^2, R ³ is a hydrogen atom or an unsubstituted or substituted monovalent hydrocarbon group )
The oxime compound represented by is continuously injected into the second reactor, (c) the reaction product continuously flowing out from the lower part of the second reactor is placed in a slurry tank, and (d) a by-product from the reaction product. The precipitated NH ⁴ X was removed and the organic liquid phase was distilled, from which the general formula R ¹ _4-n Si (ON = CR ² R
³ ) A method for continuously producing oxime silane, which comprises recovering the oxime silane represented by _n . 2. Amount of ammonia gas to be absorbed into the organic solvent before entering the first reactor and to be injected into the first reactor of step (a), while ammonia flowing out from the second reactor of step (b) is absorbed. 1.10n to 1.4 per mol of halogenated silane
The method for continuously producing oxime silane according to claim 1, wherein the amount is 5 nmole. 3. The continuous method for producing oxime silane according to claim 1, wherein the solvent recovered in step (d) is circulated in the first reactor.