JP2512348B2 - Butadienyl group-containing siloxane compound and method for producing the same - Google Patents

Description

Detailed Description of the Invention

[0001]

TECHNICAL FIELD The present invention relates to a novel siloxane compound having a 1,3-butadienyl group and a method for producing the same.

[0002]

2. Description of the Related Art Two [2- (1,3-
Butadienyl)] group-bonded silane compounds, that is, bis-substituted-1,3-butadienylsilane derivatives are known compounds (JP-A 61-205286).
However, a siloxane compound in which a [2- (1,3-butadienyl)] group is bonded to each of the silicon atoms at both ends of the siloxane skeleton has not yet been known.

[0003]

Therefore, according to the present invention, each of the silicon atoms at both ends of the siloxane skeleton has [2-
An object of the present invention is to provide a siloxane compound having a (1,3-butadienyl)] group bonded thereto and a method for producing the same.

[0004]

According to the present invention, the following formula [1]:

Embedded image (wherein R is a substituted or unsubstituted C 1 -C 1).
10 monovalent hydrocarbon groups, each R may be the same group or different groups, and n is an integer of 0 to 100. ) Butadienyl group-containing siloxane compounds represented by

Butadienyl Group-Containing Siloxane Compound The siloxane compound of the present invention is highly reactive with each of the two terminal silicon atoms of the siloxane chain [2-
A significant feature is that the (1,3-butadienyl)] group is bonded.

In the formula [1], the group R represents a monovalent hydrocarbon group having 1 to 10 carbon atoms, for example, a lower alkyl group, a lower alkenyl group, an aryl group, etc. as typical ones. Some or all of the hydrogen atoms bonded to the carbon atoms may be replaced by halogen atoms or the like. Specific examples of the lower alkyl group include a methyl group, an ethyl group, a propyl group, a butyl group, and a group in which some or all of the hydrogen atoms of these groups are substituted with halogen atoms, and the like. Examples of the vinyl group, allyl group, butenyl group and groups in which some or all of the hydrogen atoms of these groups are substituted with halogen atoms,
Examples of the aryl group include a phenyl group, a tolyl group, a naphthyl group, and a group in which some or all of the hydrogen atoms thereof are replaced with halogen atoms. A plurality of these groups R may be all the same or different from each other. Furthermore, n is 0 to 10
Represents an integer of 0.

In the present invention, a typical butadienyl group-containing siloxane compound has, for example, the formula [4]:

Embedded image (in the formula, R is the above-mentioned bird). Representative examples of R in the formula [4] include a lower alkenyl group such as a methyl group, a vinyl group, an allyl group and a butenyl group, an aryl group such as a phenyl group, a tolyl group and a naphthyl group, and hydrogen of these groups. Examples include groups in which some or all of the atoms are replaced with halogen atoms. Further, R's may be the same group or different groups.

More specific examples of the compound of the formula [4] include 1,1,3,3-tetramethyl-1,3-bis [2
-(1,3-Butadienyl)] disiloxane, 1,3-
Dimethyl-1,3-divinyl-1,3-bis [2-
(1,3-Butadienyl)] disiloxane and 1,1,
3,3-Tetravinyl-1,3-bis [2- (1,3-
Butadienyl)] disiloxane.

Production Method The butadienyl group-containing siloxane compound of the formula [1] can be easily produced by the following method (1) and method (2). Method (1): The compound of formula [1] is
(A) The following formula [2]:

2-magnesium-1,3-butadiene represented by the formula: wherein X ¹ represents a halogen atom, and (b) the following formula [3]:

(Wherein, X ² is a halogen atom or an alkoxyl group, and two X ² may be the same or different,
R and n have the above-mentioned meanings. ) And a siloxane compound represented by the formula (1).

In this production method, the Grignard reagent used is the 2-halogenated magnesium-1,3-butadiene represented by the above formula [2]. This halogen atom may be any of a chlorine atom, a bromine atom and an iodine atom.

This Grignard reagent can be prepared according to a method known per se, for example, the method described in J. Org. Chem., 44 , 4788 (1979) in an ether solvent such as tetrahydrofuran, dioxane, diethyl ether or the like. Thus, it can be easily produced by mixing 2-halo-1,3-butadiene and metallic magnesium.

The siloxane compound to be reacted with the Grignard reagent is a halogen-substituted or alkoxyl group-substituted siloxane compound represented by the above formula [3], which is the target butadiene compound containing a butadienyl group of the formula [1]. It has a siloxane skeleton corresponding to.

In the formula [3], the halogen atom represented by the group X ² may be any of a chlorine atom, a bromine atom and an iodine atom, and the alkoxyl group may be a methoxyl group, an ethoxyl group, a methoxyl-substituted ethoxyl group,
Ethoxyl-substituted ethoxyl groups, propoxyl groups, butoxyl groups and groups in which some or all of the hydrogen atoms bonded to the carbon atoms of these groups are substituted with halogen atoms are exemplified. Furthermore, the two groups X ² may be the same or different from each other.

The halogen-substituted or alkoxyl group-substituted siloxane compound can also be produced by a method known per se. The reaction between the Grignard reagent and the siloxane compound is carried out by cooling the Grignard reagent prepared in an ether solvent such as tetrahydrofuran which does not inhibit the reaction to room temperature or below and dropping the siloxane compound in the presence of an inert gas. It should be done. In contrast to the above, it is also possible to carry out the reaction by diluting the siloxane compound in a solvent and dropping the previously prepared Grignard reagent under cooling and stirring. The reaction temperature is generally -50 ° C to the boiling point of the solvent, preferably 0 to 30 ° C.
It is said. If the reaction temperature is too low, the reaction proceeds slowly, which is not practical, and if it is too high, side reactions may occur. The reaction time is generally 5 minutes to 6 hours, preferably 30 minutes to 3 hours.

The amount ratio of the Grignard reagent to the siloxane compound used is on a molar basis in the range of 1: 0.1 to 1: 2, preferably 1: 0.2 to 1: 1. The amount of the solvent used, that is, the dilution ratio of the reaction solution may be determined in consideration of reaction heat, volumetric efficiency, and the like.

As described above, the reaction between the Grignard reagent and the siloxane compound is usually carried out in an inert gas atmosphere. As such an inert gas, argon, helium, nitrogen, etc. may be used alone or in combination of two or more. Although they can be used in combination, nitrogen gas is preferable from the economical point of view. By the above reaction, the butadienyl group-containing siloxane compound of the present invention represented by the formula [1] can be produced.

Method (2): Among the butadienyl group-containing siloxane compounds of the present invention, the above formula [4], that is, the formula:

Embedded image (wherein R is as defined above) has the formula [5]:

[Image Omitted] (wherein Y is a hydrolyzable atom or group, and R is as defined above), and also by a method having a step of hydrolyzing and condensing a butadienyl group-containing silane. can get.

In the formula [5], R is as described above, but typical examples are methyl group, ethyl group, propyl group,
Lower alkyl group such as butyl group, vinyl group, allyl group,
Lower alkenyl groups such as butenyl groups, phenyl groups, tolyl groups, aryl groups such as naphthyl groups, and some or all of the hydrogen atoms of these groups are substituted with halogen atoms such as fluorine, chlorine and bromine. Groups and the like.
The hydrolyzable atom or group is, for example, a halogen atom selected from the group consisting of chlorine atom, bromine atom and iodine atom; methoxyl group, ethoxyl group, methoxyl group-substituted ethoxyl group, ethoxyl group-containing ethoxyl group, propoxy. And an alkoxyl group such as a butoxyl group; or a group in which some or all of the hydrogen atoms bonded to the carbon atoms of these alkoxyl groups are substituted with a halogen atom such as fluorine, chlorine or bromine, and preferably A halogen atom and an alkoxyl group.

To hydrolyze the silane containing butadienyl group of the formula [5], an aqueous solution of an alkali compound such as sodium hydroxide, potassium hydroxide or sodium hydrogencarbonate is prepared at room temperature, and the hydrolysis reaction is carried out therein. Solvents that do not inhibit, for example, alkyl compounds such as pentane, hexane, heptane, aryl compounds such as benzene, toluene, xylene, ether compounds such as tetrahydrofuran, dioxane, diethyl ether, halogenated alkyls such as methylene chloride, chloroform and carbon tetrachloride. It is carried out by dropping butadienyl group-containing vinylsilane diluted with a compound to react. On the contrary, it is also possible to dilute the above-mentioned vinyl silane with the above-mentioned solvent and drop the aqueous solution of the above-mentioned alkaline compound therein to carry out the reaction.

By such an operation, Y in the silane of the formula [5] is hydrolyzed and converted into a silanol group.
The generated silanol group immediately undergoes condensation with the silanol group of another molecule, and as a result, the desired compound of formula [4] is produced.

The reaction temperature for such hydrolysis and condensation is generally 0 ° C to the boiling point of the solvent, preferably 10 to 30 ° C.
If the reaction temperature is too low, the progress of the reaction is too slow to be practical, and if it is too high, a side reaction may occur. The reaction time is usually 30 minutes to 24 hours, typically 2 to 24 hours.
12 hours. In this method, the amount ratio of the silane of formula [5] and the alkali compound is 1: 0.5 to 1: 1 on a molar basis.
The range is 0, preferably 1: 1 to 1: 5. The amount of solvent used (dilution rate) may be determined in consideration of reaction heat, volumetric efficiency, and the like. In the above hydrolysis reaction, only one kind of butadienyl group-containing silane may be used, and two or more kinds of butadienyl group-containing silanes having different groups represented by R and Y or different kinds of halogen atoms are used. May be. When two or more butadienyl group-containing silanes having different Rs are used, a butadienyl group-containing siloxane having different Rs bonded to the two silicon atoms of the general formula [4] can be produced.

The silane compound of the formula [5] used as a starting material in the above method (2) is, for example, a compound represented by the general formula [6]:

[Chemical 6] (In the formula, R and Y are as described above.) And the Grignard reagent represented by the formula [2] can be reacted to synthesize.

The reaction between the silane of the formula [6] and the Grignard reagent of the formula [2] is carried out by diluting the Grignard reagent prepared by diluting with an ether solvent such as tetrahydrofuran which does not inhibit the reaction to room temperature or below. In the presence of an inert gas, the above silane is added dropwise to react with the silane. Conversely, it is also possible to carry out the reaction by diluting the above silane with a solvent and dropping the Grignard reagent prepared above under cooling and stirring.

[0024]

Example 1 300 ml of a tetrahydrofuran solution of 2-magnesium chloride-1,3-butadiene (330 mmol) in a 2 l flask equipped with a reflux condenser, a thermometer, a stirrer and a dropping funnel was placed under a nitrogen stream. After charging in
The inside of the flask was cooled to 0 ° C., and 16.7 g (82 mmol) of 1,1,3,3-tetramethyl-1,3-dichlorosiloxane was added dropwise. Then, the reaction solution was heated and aged for 1 hour while refluxing tetrahydrofuran.
After aging, remove excess Grignard reagent in the reaction solution.
Hydrolysis was performed using an aqueous solution of ammonium chloride. Next, the aqueous layer was extracted with n-hexane, and the obtained organic layer was distilled to obtain 8.8 g of the target compound (yield 45%).

This compound was measured by NMR, mass spectrum, infrared absorption spectrum and elemental analysis. The results are shown below. From the measurement results, the obtained compound was identified as 1,1,3,3-tetramethyl-1,3-
It is identified as bis [2- (1,3-butadienyl)] disiloxane.

[0026]

[Chemical 7] 5.57,5.80 (2d, J = 3Hz, 2H, C H 2 = C) 6.49 (dd, J = 10.17Hz, 1H, C H = CH 2) Mass spectrum; 238 (M ⁺⁾ , 223 (M ⁺ —CH ₃ )

Infrared absorption spectrum; shown in FIG. Elemental analysis; as C ₁₂ H ₂₂ OSi ₂

Example 2 A flask similar to that used in Example 1 was charged with 330 ml of a tetrahydrofuran solution of 2-magnesium chloride-1,3-butadiene (660 mmol) under a nitrogen stream, and then the temperature inside the flask was set to 0 ° C. Cooled to 1,6,3 g of 1,1,3,3-tetramethyl-1,3-dichlorodisiloxane (33
0 mmol) was added dropwise, and then the reaction temperature was adjusted to 25 ° C.,
Aged for 2 hours.

After the aging, the reaction solution was treated in the same manner as in Example 1 to obtain 47.1 g of the desired compound (yield 60
%). As a result of performing the same analysis as in Example 1 on this compound, the compound was 1,1,3,3-tetramethyl-1,3-bis [2- (1,3-butadienyl)] disiloxane. It was confirmed that there is.

Example 3 A 1-liter flask equipped with a reflux condenser, a thermometer, a stirrer and a dropping funnel was charged with 400 ml of an aqueous solution of 100.8 g (1.8 mol) of potassium hydroxide, and then the temperature in the flask was raised to 25 ° C. Maintaining the temperature, 200 ml of a methylene chloride solution containing 92.4 g (0.6 mol) of 2- (methylvinylmethoxysilyl) -1,3-butadiene was added dropwise. After completion of dropping, the reaction solution was aged at 25 ° C. for 10 hours while stirring. After the reaction was completed, 300 ml of n-hexane was added to the reaction solution.
In addition, the organic layer was washed twice with 100 ml of water, and the obtained organic layer was distilled to obtain the desired compound 4
0.9 g was obtained (yield 52%).

The obtained compound was measured by ¹ HNMR, mass spectrum, infrared absorption spectrum and elemental analysis. The results are shown below. From this measurement result, it was confirmed that this compound was 1,3-dimethyl-1,3-divinyl-1,3-bis [2- (1,3-butadienyl)] disiloxane.

[0032]

Embedded image 5.61,5.81 (2d, J = 3Hz, 4H, C H 2 = C) 5.59~6.32 (m, 6H, Si-C H = C H 2) 6.38 (dd, J = 10,17Hz, 2H, C-C H = CH 2) mass ^{spectrum; 262 (M +), 247} (M + -CH 3)

Infrared absorption spectrum; shown in FIG. Elemental analysis; as C ₁₄ H ₂₂ OSi ₂

Example 4 In a flask similar to Example 1, potassium hydroxide 112.0
After charging 450 ml of an aqueous solution of g (2.0 mol), the inside of the flask was cooled to 5 ° C., and 300 ml of a chloroform solution of 154.0 g (1.0 mol) of 2- (methylvinylmethoxysilyl) -1,3-butadiene was added dropwise. After completion of the dropwise addition, the reaction temperature was set to 5 ° C., and the mixture was aged for 20 hours with stirring, then 46 g of the desired compound was obtained in the same manner as in Example 1 (yield 3
5%). The obtained compound was analyzed in the same manner as in Example 1. As a result, the compound was found to be 1,3-dimethyl-
It was confirmed to be 1,3-divinyl-1,3-bis [2- (1,3-butadienyl)] disiloxane.

[0035]

INDUSTRIAL APPLICABILITY The novel siloxane compound of the present invention has a molecular structure in which very reactive butadienyl groups are bonded to both ends of a siloxane chain, and thus a silicone resin and various organic resins are synthesized. It is expected that it will be widely used as an intermediate or a modifier for the purpose. In particular, those having an alkenyl group bonded as a substituent of a silicon atom in the siloxane skeleton can be introduced with various functional groups and a crosslinking reaction, and are expected to have wider applications in the silicone industry.

[Brief description of drawings]

FIG. 1 is a graph showing an infrared absorption spectrum of a siloxane compound synthesized in Example 1.

2 is a graph showing an infrared absorption spectrum of the compound obtained in Example 3. FIG.

Claims (3)

(57) [Claims] 1. The following formula [1]: (Wherein, R is a substituted or unsubstituted C 1 -C 1)
And each R may be the same group or different groups. N is 0 to 10
It is an integer of 0. ) A siloxane compound containing a butadienyl group represented by 2. (a) The following formula [2]: (In the formula, X ¹ represents a halogen atom.) 2
Magnesium halide-1,3-butadiene,
(B) The following formula [3]: (In the formula, X ² is a halogen atom or an alkoxyl group, and two X ² may be the same or different, R
And n have the above-mentioned meanings. The siloxane compound represented by these is reacted with the siloxane compound of Claim 1 characterized by the above-mentioned. 3. A general formula [4]: A method for producing a butadienyl group-containing siloxane compound represented by the formula (wherein R is as described above), which is represented by the formula [5]: (In the formula, Y represents a hydrolyzable atom or group, and R is as described above.) A production method having a step of hydrolyzing and condensing a butadienyl group-containing silane represented by the formula.