JPS6039078B2 - Method for manufacturing disilanes - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a method for producing industrially useful disilanes by re-equilibrating monosilanes and disilanes.

In the present invention, monosilanes and disilanes refer to methyl and/or SiH4 and Si, respectively.
Or it is used to mean chlorine-substituted products, that is, methylchlorosilanes and methylchlorodisilanes.

In the silicone industry, methylchlorosilanes are generally produced by a direct process using silicon metal and methyl chloride as raw materials.

In this direct method, after removing the necessary monosilanes, a so-called high-boiling afterglow consisting mainly of disilanes remains.
In recent years, there has been an urgent need to convert this high-boiling point residue into industrially useful compounds due to problems such as environmental pollution. Therefore, in recent years, many attempts have been made to convert the disilanes in the high boiling point residue into useful monosilanes by breaking the silicon-silicon bond using various methods. When the silicon-silicon bond is broken by the method described in Publication No. 50-37732, the reaction proceeds as shown in formula '1} in tetrachlorodimethyldisilane, which is abundant in the high-boiling point residue, and (CH
3) q2SjSiq2 (CH3) 10Rq Algae (CH3)
RSiC12 ten (CH3) Sic13
{1} (where R is hydrogen or a monovalent hydrocarbon group) This results in the production of a large amount of industrially very useful dichlorosilanes as well as less important methyltrichlorosilane.

It goes without saying that such dichlorosilanes are important industrially, but monochlorosilanes are also very useful, and efforts have been made to obtain these monochlorosilanes from the scale-splitting reaction of disilanes. Do/In case (CH3)
3SiSiC1 (CH3)2, (Cmelon)2CISiSi
It is denoted by C1(CH3)2.

Monochlorodisilane and dichlorodisilane are required. As a method similar to the present invention, Ishikawa et al.
J. ○r scale nometal, Chem, 2363 (19
70)) The method shown by the following formula is known, but (
The actual situation is that the tetramethylsilane produced in the above formula must be taken out of the reaction system, resulting in a low yield.

The present invention eliminates these drawbacks and provides a new method for producing industrially useful pentamethyldichlorodisilane and tetramethyldichlorodisilane by reacting monosilanes and disilanes.

More specifically, monosilanes represented by the general formula (CH3)mSiC14-m and general formula (CH3)nSi2C
A compound of the general formula (CH3) pSi2CI6-, which is characterized by reacting a disilane represented by I6-n at a temperature of 10,000 to 400 qo in the presence of aluminum chloride.
The present invention relates to a method for producing disilanes represented by p.

(In each of the above formulas, when n is 6, m is a number selected from 1 and 2; when n is a number selected from 1, 2, and 3, m is a number selected from 3 and 4. In addition, p is a number selected from 4 and 5.) That is, the present invention consists of chlorinating and methylating disilanes by re-equilibrating them with appropriate monosilanes. For disilanes that do not have chlorine atoms such as hexamethyldisilane, disilanes are chlorinated with monosilanes that have many chlorine atoms such as dimethyldichlorosilane and methyltrichlorosilane. In the case of disilanes having a large number of chlorine atoms, such as the disilane fraction, the disilane is methylated with a monosilane having few chlorine atoms, such as trimethylchlorosilane.

The monosilanes represented by the general formula (CH3)mSiC14 used in the present invention may be a single monosilane or a mixture, and this type of monosilanes can be easily obtained by a direct method.

General formula (CH3)nSi2CI6[
The disilanes represented by are those obtained in the form of a mixture as a disilane fraction in the high-boiling point residue obtained by the direct method, those obtained from them by using crabs, or those obtained by methylating this by the Grignard method. is used.

Note that these mixed disilanes may contain disilanes other than those within the scope of the present invention.

The blending amounts of these monosilanes and disilanes are selected from a fairly wide range depending on various conditions, but usually the aim is to obtain a large amount of the desired disilanes, so considering the equilibrium state, monosilanes It is preferable to use 1 to 5 times the mole of disilanes.

Aluminum chloride used in the present invention is used in a catalytic amount, but normally an amount of 0.5 to 50 mol % based on the disilanes is appropriate, and larger amounts are economically disadvantageous. Not only that, but it also becomes difficult to separate aluminum chloride from the desired disilanes.

On the other hand, if the amount is less than this, a long time is required for the reaction to proceed sufficiently, which is economically disadvantageous. The reaction is usually 10
The temperature is selected in the range of 0:00 to 400°C, and the reaction is completed within several tens of minutes to several tens of hours.

If the reaction temperature is below 10,000, the reaction will not proceed;
When the temperature is higher than 0, the Si--C bond and the C-bond are broken as a side reaction, and the by-product of hydrocarbons is significant. Although a closed reactor is used as the reactor, a reactor having an appropriate layer that allows sufficient mixing of the reactants is preferred. Disilanes obtained according to the present invention, namely (CH3)3SjSiC1(CH3)2
and (CH3)2CISiSiC1(CH3)2 are used to produce industrially useful monosilanes by utilizing the scale splitting reaction of the silicon bond shown in formula {11.

Alternatively, by reacting with an aromatic dihalide (wherein X is a group selected from a chlorine atom and a methyl group,
Y is a halogen atom selected from chlorine and bromine atoms.

) Used to produce polymerizable silicon compounds with excellent heat resistance.

The invention will be explained in more detail in the following examples. Example 1 (CH3)2SIC12194 (1.5 mol), (C
373 moles (0.5 mol) of di-Si(CH3) and 13 moles (20 mol %) of aluminum chloride were placed in a sealed reaction vessel, and heated to 16,000 ℃ after purging with nitrogen.

When heated for 30 minutes, (CH3)3SiSi(CH3
)3 completely disappears, and (CH3)3SiSiCI(
CH3)28.3m (0.05 mol), (CH3)2C
277.6 moles (0.41 mol) of ISiSjC1(CH3) were obtained.

Other products include ((CH3)2CISiSiC1
2(CH3) was obtained over 8.3 days (0.04 mol). Example 2CH3SIC13215 (1.5 mol), (
CH3)3SiSi(CH3)373(0.5 mol)
and aluminum chloride (20 mol%) were placed in a sealed reaction vessel and heated at 160°C for 4 hours after purging with nitrogen. Only (CH3)3SiSiC1(CH3)2 was present?
6.6 hours (0.46 mol) was obtained.

Example 3 (CH3)4Si100 (1.14 mol), (CH3
) CI2SiSiC12 (CH3) 114 (0.5 mol) and aluminum chloride 5 (7.5 mol %) were placed in a sealed reaction vessel and heated at 14,000 ℃ for 2 hours after purging with nitrogen (CH3) 3SiSiC1 (CH3) 213 (0.08 mol) and (CH3)2CISiSjC1
(CH3) 253 mol (0.28 mol) was obtained.

Other products include (CH3)2CISiSiC12(C
H3) was obtained in small amounts, but (CH3)3SiSi(CH
3) 3 was not obtained at all. Example 4 (CH3)3SICI1632 (1.5 mol), (CH
3) CI2SiSiC1 (CH3) 2104 evening (0.5
When aluminum chloride (7.5 mol%) was placed in a sealed reaction vessel and reacted for 1,600,024 hours after purging with nitrogen, (C ratio) 3SiSiCl (CH3) (0.13 mol) and (CH3) were obtained. 2CISiSiC1
(CH3)2479 (0.25 mol) was obtained.

Example 5 (C ratio) 3SICI130 (1.2 mol), (CH3)
CI2SiSiC12(CH3)689 (0.3 mol)
, aluminum chloride (2.5 mol%) was placed in a sealed reaction vessel and reacted for 1 hour with 25,000 nitrogen chloride, (CH3)3SjSjC1 (CH3)21
0 (0.06 mol) and (CH3)2CISjSj
C1(CH3)226 (0.14 mol) was obtained.

Similarly to Example 3, other products (CH3)2C
Although a small amount of ISiSiC12(CH3) was obtained (CH3
)3SjSj(CH3)3 was not obtained at all. Example 6 (CH3)3SIC1200 (1.85 mol), disilane fraction in the high boiling point residue in the direct method represented by the general formula (CH3)2.5Si2CI3.5 (boiling point 150~
16000) 100 nights and aluminum chloride 20 nights (
0.15 mol) was placed in a sealed reaction vessel, and after purging with nitrogen, 16
Heated at 0°C for 24 hours.

(CH3)3SiSjC1(C
H3)217(0.10 mol) and (CH3)2C
256 (0.30 mol) of ISiSiC1(CH3) was obtained.

Claims (1)

[Claims] 1 Monosilanes represented by the general formula (CH_3)_mSiCl_4_-_m and the general formula (CH_3)_nSi
General formula (CH_3)_pS, characterized by reacting disilanes represented by _2Cl_6_-_n at a temperature of 100°C to 400°C in the presence of aluminum chloride.
A method for producing a disilane represented by i_2Cl_6_-_p. (In each of the above formulas, when n is 6, m is a number selected from 1 and 2; when n is a number selected from 1, 2, and 3, m is a number selected from 3 and 4. Also, p is a number selected from 4 and 5.)2 Monosilanes (CH_3)_2SiCl_2 and disilanes (CH_3)_3SiSi(CH_3)
_3 to react with (CH_3)_2ClSiSiCl
A method according to claim 1 for obtaining (CH_3)_2. 3 As monosilanes (CH_3)SiCl_3,
As disilanes (CH_3)_3SiSi(CH_3
)_3 to form (CH_3)_3SiSi(CH
_3) The method according to claim 1 for obtaining _2Cl. 4 Monosilanes (CH_3)_4Si and disilanes (CH_3)Cl_2SiSiCl_2(
CH_3) to react with (CH_3)_3SiSiC
l(CH_3)_2 and (CH_3)_2ClSiS
A method according to claim 1 for obtaining iCl(CH_3)_2. 5 As monosilanes (CH_3)_3SiCl,
As disilanes (CH_3)Cl_2SiSiCl_
2(CH_3) to form (CH_3)_3SiS
iCl(CH_3)_2 and (CH_3)_2ClS
Claim 1 for obtaining iSiCl(CH_3)_2
The method described in section. 6 As monosilanes (CH_3)_3SiCl,
As disilanes (CH_3)Cl_2SiSiCl(
By reacting with CH_3)_2, (CH_3)_3SiS
iCl(CH_3)_2 and (CH_3)_2ClS
Claim 1 for obtaining iSiCl(CH_3)_2
The method described in section. 7 As monosilanes (CH_3)_3SiCl,
As a disilane, the disilane fraction in the distillation residue of methylsilane is reacted with (CH_3)_3SiSiCl.
(CH_3)_2 and (CH_3)_2ClSiSi
A method according to claim 1 for obtaining Cl(CH_3)_2.