JPH02306980A - Production of alpha,omega-dihydrogen organopolysiloxane - Google Patents

Abstract

PURPOSE:To obtain the title compound useful as a raw material for silicone rubber, surface treating agent, etc., having fixed chain length free from distribution of siloxane unit in high selectivity by reacting a specific cyclic silicone with a chlorosilane and water in the presence of an inorganic solid compound. CONSTITUTION:A cyclic silicone shown by formula I (R<1> and R<2> may be the same or different and H, alkyl, alkenyl, aryl or halogenated alkyl; n is 3-10) is reacted with a chlorosilane shown by formula II and water in the presence of an inorganic solid compound (preferably silica gel) to give a compound shown by formula III. Hexamethylcyclotrisiloxane, etc., may be cited as the compound shown by formula I and dimethylchlorosilane, etc., as the compound shown by formula II. The amount of the compound shown by formula II used is preferably 2-4mols based on 1mol compound shown by formula I. The amount of the inorganic solid compound used is preferably 1-50wt.%.

Description

Detailed Description of the Invention [Industrial Application Field] The present invention relates to a method for producing α,ω-dihydrogenorganoborisiloxane, and more specifically, a method for producing α,ω-dihydrogenorganoborisiloxane, which has no distribution in siloxane units and has a constant siloxane chain length. This invention relates to a method for producing α,ω-dihydrogenorka'novolisiloxane.

[Conventional technology and its problems]

α, ω having 5i-H groups at both ends of the polysiloxane chain
-Dihydrogen organoborisiloxane is used in a wide range of industrial fields as a raw material for silicone rubber and modified silicone, or as a surface treatment agent. Conventionally,
Examples of the method for producing α1 ω-dihydrodiene organopolysiloxane include (I) ring-opening polymerization of tetramethyldisiloxane and octamethylcyclotetrasiloxane, and (2) hydrolysis of dialkyldichlorosilane.

A method of obtaining ω-dichloroorganopolysiloxane and then reducing it with lithium aluminum hydride [Bolish Journal of Chemistry (Polish J
internal or Chemist'ry), 53
Vol. 6, p. 1363, 1979], and (3) a method of obtaining it by disproportionation of tetramethyldisiloxane and chlorosilane [West German Patent No. 2,630,744].

However, all of these methods basically utilize an equilibration reaction, resulting in a distribution of siloxane units in the product, making it impossible to produce products with a specific chain length in good yield. There was a problem.

[Means to solve the problem]

Under such circumstances, the present inventors conducted various studies to solve the above problems, and as a result, a specific cyclic silicone,
When chlorosilane and water are reacted in the presence of an inorganic solid compound, a highly selective α,ω-dihydrodiene organoborisiloxane with a certain chain length corresponding to the raw material cyclic silicone and no distribution in siloxane units is produced. The present invention has been completed based on the discovery that this can be obtained.

That is, the present invention relates to the following general formula (n) (R'll''SiO)l, (II) [wherein R' and R2 may be the same or different, a hydrogen atom, an alkyl group, an alkenyl group, an aryl group] or a halogenated alkyl group, and n is an integer of 3 to 10], a cyclic silicone represented by the following general formula (III)
R'R'5i)l[j! (III)
The following general formula (I) 11R'R,'5iO characterized by reacting chlorosilane represented by [wherein R' and R2 have the same meanings as above] and water in the presence of an inorganic solid compound. (R'R''5iO),,SiR'
The present invention provides a method for producing an α,ω-dihydrogenorganopolysiloxane represented by the following formula: l''ll (I) [wherein R', R' and n have the same meanings as above].

The reaction in the production method of the present invention is basically a two-phase reaction between a phase consisting of cyclic silicone (II) and chlorosilane (NL) and an aqueous phase, and proceeds according to the following reaction formula using an inorganic solid compound as a catalyst. it is conceivable that.

...... (2) (■) + (V) → tlR'R25io (R'R'5iO
). SiR'R"ll... (3) That is, first, chlorosilane (III) undergoes hydrolysis to generate the corresponding silanol ([V) and hydrogen chloride (reaction formula (I)). This hydrogen chloride Cyclic silicone (II) and chlorosilane (I) react by the catalytic action of
(Reaction formula (2)). Next, α-chloroω-hydrogen-organoborisiloxane (V) undergoes a dehydrochlorination reaction with silanol (IV) to give α,ω-dihydrogen-organoborisiloxane (reaction formula (3)).
.

In the production method of the present invention, the cyclic silicone (■) which is the starting material for the production of α,ω-dihydrodieneorganoborisiloxane (f) is, for example, hexamethylcyclotrisiloxane, hexaethylcyclotrisiloxane, hexaethylcyclotrisiloxane, Ethylcyclotrisiloxane, trinotyltrivinylcyclotrisiloxane, trinotyltriphenylcyclotrisiloxane, octamethylcyclotetrasiloxane, octaethylcyclotetrasiloxane, octaphenylcyclotetrasiloxane, tetramethyltetraphenylcyclotetrasiloxane, tetra Examples include methyltetravinylcyclotetrasiloxane, tetra(trifluoropropyl)tetramethylcyclotetrasiloxane, dicamethylcyclopentasiloxane, and dodecamethylcyclohexasiloxane.

Examples of the other raw material, chlorosilane (III), include dimethylchlorosilane, diethylchlorosilane, diphenylchlorosilane, and divinylchlorosilane.

Furthermore, the inorganic solid compound used as a catalyst in the production method of the present invention is preferably one that is insoluble and uniformly dispersed in the reaction solution, such as silica gel, titanium dioxide, silica/alumina, and the like.

Among these, silica gel is particularly preferably used.

Here, silica gel refers to an amorphous silicic acid polymer, and although any type of silica gel can be used in the present invention, it is preferable to use one with a small particle size because the reaction rate can be accelerated with a small amount used.

In order to produce α,ω-dino-hydrodienolka'novolisiloxane (I) by the production method of the present invention, the above chlorosilane (■I) is added to a mixture of the above cyclic silicone (■), an inorganic solid compound, and water. It is preferable to do so.

The amount of chlorosilane (I) used in the reaction is 2 to 10 times the mole of the cyclic silicone (II), and further 2 to 4 times the mole of the cyclic silicone (II).
It is preferably about twice the molar amount, especially about 3 times the molar amount.

The amount of the inorganic solid compound to be used is appropriately selected depending on the reactivity of the cyclic silicone (II) and chlorosilane (III), but is 1 to 50% by weight based on the cyclic silicone DI>.
It is preferable that it is in the range of .

Also, as a rule, water is used in a stoichiometric excess. That is, it is preferably used in an amount of 1 to 500 times, preferably 5 to 20 times, the amount of cyclic silicone (II).

A reaction solvent may or may not be used, but when hexamethylcyclotrisiloxane, which is solid at room temperature, is used as the cyclic silicone, it may be used to facilitate the reaction. Examples of the solvent used include hydrocarbon series solvents that are immiscible with water, such as pentane, hexane, heptane, benzene, and toluene.

The reaction in the production method of the present invention varies depending on the reactivity of the cyclic silicone (■), but usually chlorosilane (i [
I) The addition is completed in 1 to 5 hours under room temperature conditions. By distilling the obtained reaction solution under normal pressure, preferably under reduced pressure, the unreacted cyclic silicone and chlorosilane present can be easily separated, and α,ω-dihydrogenocarinopolysiloxane can be obtained. Incidentally, the cyclic silicone and chlorosilane recovered here can be used again in the reaction of the present invention.

〔Example〕

The present invention will be explained in more detail below with reference to Examples, but the present invention is not limited to these Examples.

Example 1 Synthesis of z,9-cyhydrogentecamethylpentasiloxane [In general formula (I), lI'=R'=[11,,
n=3]: 100 g of hexamethylcyclotrisiloxane, 100 g of hexane, and 81 g of water in a No. 11 flask equipped with a dropping funnel.
1 Silica gel (Merck Kieselgel 60.250~
400 mesh) 5.0g is charged. 127.7 g of dimethylchlorosilane was added dropwise over 30 minutes with sufficient stirring.

After 30 minutes, return the flask to room temperature and continue stirring.

After 1 hour, the stirring is stopped and the Kieselgel is filtered.

The obtained Uranami is distilled to remove excess dimethylchlorosilane. Transfer the obtained solution to a separating funnel and add 200mj
? (twice with saturated hydrogen carbonate) IJum aqueous solution 20
Separate the solution twice with 0ml and 200mj7 of water. After the water in the solution is completely removed by azeotroping with benzene, it is distilled under reduced pressure to obtain 137.3 g (yield: 85.5%) of 1,9-dihydrodiene demethylbentasiloxane. All of the raw materials hex→)゛ and methylcyclotrisiloxane had reacted.

Me Me Me Me Me Me Me Me Me Me Me Me #, 5
7℃/0.5 rnra 11gM5 355 (
M"-1), 34HM"-15)IR21
28c+a-'(5i-II)"5i-N&l
R; ppta (δ) (in heavy benzene, T14S standard) -6,73 (I and 9-3i) -19,78 (3 and ?-5i) -21,57 (5-3i)'tl-Hll; ppm (δ) (in heavy benzene, C, I+, δ = 7.15 standard) 0, 16 (I8
11,s) 0,18 (I211,d, 311z) 4.96~
5.00 (211, bs) Example 2 Synthesis of 1.11-dihydrodiendomethylhexasiloxane [In general formula (I), It'=R''=C11,
, n=4): 500 g of octamethylcyclotetrasiloxane, 304.2 g of water in a 2E flask equipped with a dropping funnel.

Silica gel (Merck Kieselgel 60.250-4
Charge 00 mesh >50.5g.

dimethylchlorosilane 479 while stirring thoroughly,
6 g was added dropwise over 30 minutes. After 30 minutes, return the flask to room temperature and continue stirring. After 4 hours, stirring is stopped and the Kieselgel is filtered. The obtained filtrate is distilled to remove excess dimethylchlorosilane. The obtained solution was transferred to a separatory funnel and separated twice with 5001I11 of water, 500ml of saturated hydrogen carbonate aqueous solution, and then twice with 500ml of water.

After completely removing water in the solution by azeotroping with benzene, distillation under reduced pressure results in 1. 341 g (yield 47%) of II-dihydrogen methylhexasiloxane are obtained. The raw material suphtamethylcyclotetrasiloxane is 1
98.5g (39.7%) recovered. The yield calculated based on the reacted octamethylcyclotetrasiloxane is 7
It is 8%.

b, 13. 81'e / 0.16mm fig
MS 429 (M”-1), 415 (M
"-15) JR2128cm-' (5i-H)
"Si-NMR; ppm (δ) (in heavy benzene,
7MS standard) -6,74 (I and 11Si) -19,81 (3 right and 9-5i) -21,62 (5 and 7-3i)'II-NMR; ppi+ (δ) (in heavy benzene,
C-116, δ=7.15 standard) 0.1.8 (I2
11,s) 0,1'9 (I211,d, 2.7Hz)0.2
1 (I2B, s) 5,00 (2H, 5ept, 2.711z) Example 3 1.13-Dihydrodiene tetradeoxymethylhebutasiloxane synthesis [In general formula (I), II'=I12- C
1fs, n=5]: 20On+j with dropping funnel! 92.5 g of decamethylcyclopentasiloxane, 13.5 g of water in a flask
g, silica gel (Merck Kieselgel 60.25
0-400 mesh) Charge 15g. While stirring thoroughly, add 70.9 g of dimethylchlorosilane to 30
Drip over several minutes. After 30 minutes, return the flask to room temperature and continue stirring. After 1.5 hours, stirring is stopped and the Kieselgel is filtered. The obtained filtrate is distilled to remove excess dimethylchlorosilane. Transfer the obtained solution to a separating funnel and add 100a+j! The solution is separated twice with 100 mf of saturated sodium bicarbonate aqueous solution and then twice with 100 ml of water. After completely removing water in the solution by azeotroping with benzene, distillation under reduced pressure yielded 38.3 g of 1,13-dihydrodiene tetratecamethylheptasiloxane (yield: 30
%)can get. 31.3g (33.7%) of the raw material decamethylcyclopentasiloxane was recovered. The yield calculated based on the reacted decamethylcyclopentasiloxane is 45.2%.

b, p, 107°C/2. Carp 11gM5
489 (“-15) IR2128cm-’ (5i-H)”Si-NMI
t; ppm (δ) (in heavy benzene, Th1s standard) = 6.75 (l and 13-5i) -19,83 (3 and 1l-Si) -21,64 (5,7 and 9-5i)'fl-NMR
; ppm (δ) (in heavy benzene, TMS standard) 0.
16 (I28,s) 0, 19 (I211,d, 2.7tlz) 0.2
0 (I2)1. s) 0,21 (6H,s) 4,96 (21(,5ept, 2.711z) Example 4 ■, Synthesis of 15-dihyde-bentadecamethyloctasiloxane [In general formula (I), R1= R2=CH3
, n=6 ]: 300 g of dodecamethylcyclohexasiloxane, 122.4 g of water, 1 g of silica gel (Merck Kieselgel 60.250-400 mesh) were charged into a 21 flask equipped with a dropping funnel. 193 g of dimethylchlorosilane was added dropwise over 30 minutes with sufficient stirring.

After 30 minutes, the two flasks were returned to room temperature and stirring was continued. After 4 hours, stirring is stopped and the Kieselgel is filtered. The obtained filtrate is distilled to remove excess dimethylchlorosilane.

Transfer the obtained solution to a separating funnel and dilute with 20 (] ml of water)
2 times, 200 ml of saturated sodium carbonate aqueous solution, and 2 times
Separate the solution twice with 00 mA' water.

After completely removing water in the solution by azeotroping with benzene, distillation under reduced pressure yielded 128 g of 1,15-dihydrodiene pentatecamethyloctasiloxane (yield: 32.8
%)can get. 153.4 g (51.1%) of the raw material dodecamethylcyclohexasiloxane was recovered. The yield calculated based on the reacted dodecamethylcyclohexasiloxane is 67%.

Margin below, p, 105℃/0.14mm11gM5 56
3(M"-15) IR2132cm-'(Si-If)"St-N
MIt: 119m (δ) (7MS in heavy benzene
Standard) -6,68 (I and 15-5i) -19,76 (3 and 13-3i) -21,58 (5 and 1l-5i) -21,60 (7 and 9-5i) ')l- NMR; Ilpm (δ) (Cs in heavy benzene
1la, δ=7.15 standard) 0, l? (I21t
, s) 0, 19 (I2H, d, 2.811z) 0.21
(I2Ls) 0.22 (I211,s) 4,97 (2H,5ept, 2.811z) [Effects of the invention] The α,ω-dinohydrogenorganoborisiloxane obtained by the production method of the present invention has It has no distribution of siloxane units, has a constant chain length, and has physical properties that are completely different from mixtures obtained by conventional manufacturing methods.

that's all

Claims (1)

[Claims] 1. The following general formula (II) (R^1R^2SiO)_n(II) [In the formula, R^1 and R^2 are hydrogen atoms or alkyl groups which may be the same or different. , alkenyl group, aryl group or halogenated alkyl group, and n is an integer of 3 to 10] Cyclic silicone represented by the following general formula (III) R^
1R^2SiHCl(III) [In the formula, R^1 and R^2 have the same meanings as above]
The following general formula (I) HR^1R^2SiO(R^1R^2SiO)_nSi is characterized by reacting chlorosilane represented by and water in the presence of an inorganic solid compound.
R^1R^2H (I) [where R^1, R^2 and n
has the same meaning as above] A method for producing an α,ω-dihydrogenorganopolysiloxane represented by the following. 2. The method for producing α,ω-dihydrogenorganopolysiloxane according to claim 1, wherein the inorganic solid compound is silica gel.