JP2001026593A - Production of isocyanate group-containing siloxane compound, and aryl carbamate group-containing siloxane compound and isocyanate group-containing siloxane compound - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain the subject high-purity compounds in high yield, safely and industrially and economically advantageously by reacting a specific amino group-containing siloxane compound with a diaryl carbonate and thermally decomposing the obtained intermediate. SOLUTION: An amino group-containing siloxane compound of formula I (R1 to R3 are each a 1-8C organic group, or the like; R4 is a 1-8C organic group; (n) is 1-10; (a) is 0, 1 or 2) is reacted with a diaryl carbonate to give an aryl carbamate group-containing siloxane compound of formula II (R8 is an aryl). Then, the compound of formula II is thermally decomposed to give an isocyanate group-containing siloxane compound of formula III. The thermal decomposition of the compound of formula II is preferably carried out in the presence of an inert solvent having a boiling point higher than that of the compound of formula III. The compound of formula III may contain >=0.001 wt.% of the compound of formula II. Consequently, the objective high-purity compounds can be obtained safely in high yield without using phosgene.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to a process for producing a siloxane compound containing an isocyanate group, an aryl group-containing siloxane compound which is an intermediate product in the process, and a siloxane compound containing an isocyanate group obtained by the process. About.

[0002]

2. Description of the Related Art Isocyanate groups include, for example, hydroxyl groups,
It reacts with an organic functional group having an active hydrogen such as a primary or secondary amino group or a carboxylic acid group to form a urethane bond or a urea bond. Due to its high reactivity, for example, isocyanate It is very useful to use a group-containing polysiloxane compound as a silicone modifier for an organic compound having active hydrogen.

On the other hand, compounds containing an isocyanate group are industrially produced by reacting an amine with phosgene. According to this method, a polysiloxane compound containing an amino group is reacted with phosgene. If an attempt is made to obtain an isocyanate group-containing polysiloxane compound, the siloxane bond is cleaved by hydrochloric acid as a by-product, and the desired isocyanate group-containing polysiloxane compound cannot be obtained in good yield. Actually, for example, in US Pat. No. 3,584,024, γ-tris (trimethylsiloxy) silylpropylamine is obtained by reacting phosgene with γ-tris (trimethylsiloxy) silylpropylamine. And that 18.6 mol% of siloxane bonds were cleaved, and the desired γ-tris (trimethylsiloxy) silylpropyl isocyanate was not obtained in good yield.

On the other hand, for example, Japanese Patent Laid-Open No. 6-2281
No. 61 proposes a method for producing a corresponding isocyanate-containing polysiloxane compound by reacting an amino group-containing polysiloxane compound with phosgene in the presence of a basic substance to neutralize hydrochloric acid by-produced. I have. However, in this method, for example, γ-tris (trimethylsiloxy) silylpropyl isocyanate is obtained in Example 1, but the yield is not so good at 73.0%. A large amount of salt is generated by the reaction, so steps such as filtration or washing are required.Furthermore, there are various problems to be solved in order to promote industrialization, such as handling of highly toxic phosgene and corrosion of equipment. Existing.

Therefore, development of an industrial production method of an isocyanate group-containing polysiloxane compound instead of these is desired. For example, in US Pat. No. 5,218,133, an alkoxysilyl group is used in the presence of a basic catalyst. It has been proposed to obtain an alkoxysilyl group-containing alkyl carbamate by reacting an amine-containing amine with a dialkyl carbonate. Further, for example, US Pat. No. 3,607,901, Japanese Patent No. 2,686,420, and US Pat. Kaiping 10
JP-A-1486 proposes to obtain an alkoxysilyl group-containing isocyanate compound by separating a corresponding alkyl alcohol generated by thermal decomposition of an alkoxysilyl group-containing alkyl carbamate.

[0006]

However, as described above, when phosgene is used in the production of an isocyanate group-containing polysiloxane compound, the yield is low and the phosgene has toxicity and corrosive problems. Also,
In order to increase the yield, it is necessary to treat a salt produced as a by-product, so that there is a problem in promoting industrialization.

As an alternative method, various methods have been proposed for the thermal decomposition of an alkoxysilyl group-containing alkyl carbamate. However, in the production of an isocyanate group-containing polysiloxane compound, all methods have high yields. It is not available and is not an economically advantageous method.

The present invention has been made in view of the above-mentioned circumstances, and an object of the present invention is to provide an isocyanate group-containing siloxane compound with high purity, high yield, safety, and easy industrialization. Another object of the present invention is to provide an economically advantageous method for producing, a siloxane compound containing an aryl carbamate group which is an intermediate product in the production method, and a siloxane compound containing an isocyanate group obtained by the production method.

[0009]

In order to achieve the above object, a method for producing an isocyanate group-containing siloxane compound of the present invention comprises a compound represented by the general formula (1):

[0010]

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(Where R¹, R^Two, R^ThreeRepresents 1 to 8 carbon atoms
Organic group or -SiOR^FiveR⁶R⁷Shiroki indicated by
Si group (R^Five, R⁶, R⁷Is a hydrocarbon group having 1 to 8 carbon atoms)
And R ^FourRepresents an organic group having 1 to 8 carbon atoms, and n represents an integer of 1 to 10
A represents 0, 1 or 2; Amino)
Reacting a group-containing siloxane compound with a diaryl carbonate
And the general formula (2)

[0012]

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Wherein R ^{1 to} R ⁷ , n, and a have the same meanings as described above, and R ⁸ represents an aryl group. By subjecting the aryl group-containing carbamic acid-containing siloxane compound obtained in the first step to thermal decomposition, the compound represented by the general formula (3)

[0014]

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Wherein R ^{1 to} R ⁷ , n, and a have the same meanings as described above, and a second step of obtaining an isocyanate group-containing siloxane compound represented by the formula:

In the second step, thermal decomposition is carried out in the presence of an inert solvent having a boiling point higher than that of the isocyanate group-containing siloxane compound represented by the general formula (3) obtained by thermal decomposition. Is preferred.

Further, the present invention provides a compound represented by the general formula (2):

[0018]

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(Wherein R¹, R^Two, R^ThreeRepresents 1 to 8 carbon atoms
Organic group or -SiOR^FiveR⁶R⁷Shiroki indicated by
Si group (R^Five, R⁶, R⁷Is a hydrocarbon group having 1 to 8 carbon atoms)
And R ^FourRepresents an organic group having 1 to 8 carbon atoms;⁸Is an aryl group
Represents an integer of 1 to 10, a represents 0, 1 or 2.
You. ), An aryl group containing a carbamate aryl group
It also contains a sun compound.

The present invention further provides a compound of the general formula (1)

[0021]

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Where R¹, R^Two, R^ThreeRepresents 1 to 8 carbon atoms
Organic group or -SiOR^FiveR⁶R⁷Shiroki indicated by
Si group (R^Five, R⁶, R⁷Is a hydrocarbon group having 1 to 8 carbon atoms)
And R ^FourRepresents an organic group having 1 to 8 carbon atoms, and n represents an integer of 1 to 10
A represents 0, 1 or 2; Amino)
Reacting a group-containing siloxane compound with a diaryl carbonate
General formula (2) obtained by

[0023]

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Wherein R ^{1 to} R ⁷ , n and a have the same meanings as described above, and R ⁸ represents an aryl group. General formula (3) obtained by

[0025]

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(Wherein, R ^{1 to} R ⁷ , n and a have the same meanings as described above).

The isocyanate group-containing siloxane compound has the general formula (2)

[0028]

Embedded image

Where R¹, R^Two, R^ThreeRepresents 1 to 8 carbon atoms
Organic group or -SiOR^FiveR⁶R⁷Shiroki indicated by
Si group (R^Five, R⁶, R⁷Is a hydrocarbon group having 1 to 8 carbon atoms)
And R ^FourRepresents an organic group having 1 to 8 carbon atoms, and n represents an integer of 1 to 10
A represents 0, 1 or 2; )
0.001 weight of the siloxane compound containing an arylamino acid group
% Or more may be contained.

[0030]

BEST MODE FOR CARRYING OUT THE INVENTION In the process for producing an isocyanate group-containing siloxane compound of the present invention, first, in a first step, an amino group-containing siloxane compound is reacted with a diaryl carbonate to obtain an aryl carbamate-containing siloxane compound. .

The amino group-containing siloxane compound used as a starting material in the first step is represented by the general formula (1).

[0032]

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(Where R¹, R^Two, R^ThreeRepresents 1 to 8 carbon atoms
Organic group or -SiOR^FiveR⁶R⁷Shiroki indicated by
Si group (R^Five, R⁶, R⁷Is a hydrocarbon group having 1 to 8 carbon atoms)
And R ^FourRepresents an organic group having 1 to 8 carbon atoms, and n represents an integer of 1 to 10
A represents 0, 1 or 2; ) R^FourCharcoal indicated by
Examples of the organic group having a prime number of 1 to 8 include a methyl group and an ethyl group.
Group, propyl group, butyl group, hexyl group, octyl group
Alkyl groups such as cyclopentyl, cyclo
Cycloalkyl group such as hexyl group, for example, phenyl
Group, an aryl group such as a tolyl group, for example, a benzyl group.
Any aralkyl group such as vinyl, allyl, pro
Alkenyl groups such as a phenyl group or their carbon atoms
Part or all of the hydrogen atoms bonded to
For example, chloromethyl substituted with
Group, 3,3,3-trifluoropropyl group, 2-cyano
Unsubstituted or substituted carbon selected from ethyl group etc.
Examples thereof include monovalent organic groups represented by Formulas 1 to 8.

The organic group having 1 to 8 carbon atoms represented by R ¹ , R ² and R ³ is, for example, an unsubstituted or substituted monovalent organic group having 1 to 8 carbon atoms represented by R ^4. And the same. In the siloxy group represented by —SiOR ⁵ R ⁶ R ⁷ , the organic group having 1 to 8 carbon atoms represented by R ⁵ , R ⁶ , and R ⁷ is also, for example, unsubstituted or substituted by R ^4. can be mentioned the same monovalent organic group having 1 to 8 carbon atoms, as the siloxy group represented by such -SiOR ⁵ R ⁶ R ^7, for example, trimethylsiloxy groups, chloromethyl dimethylsiloxy group, 3,3,3
-Trifluoropropyldimethylsiloxy group and the like.

These R ^{1 to} R ⁷ may be the same or different from each other, and preferably include an alkyl group.

N represents an integer of 1 to 10, and a represents 0, 1 or 2.

More specifically, such amino group-containing siloxane compounds include, for example, γ-tris (trimethylsiloxy) silylpropylamine, γ-bis (trimethylsiloxy) methylsilylpropylamine, γ-tris (trimethylsiloxy) methylsilylpropylamine,
(Trimethylsiloxy) dimethylsilylpropylamine, γ-tris (pentamethyldisiloxanyl) silylpropylamine, γ-bis (pentamethyldisiloxanyl) methylsilylpropylamine, γ- (pentamethyldisiloxanyl) Dimethylsilylpropylamine, γ-
Tris (heptamethyltrisiloxanyl) silylpropylamine, γ-bis (heptamethyltrisiloxanyl)
Methylsilylpropylamine, γ- (heptamethyltrisiloxanyl) dimethylsilylpropylamine, γ-tris (nonamethyltetrasiloxanyl) silylpropylamine, γ-bis (nonamethyltetrasiloxanyl) methylsilylpropylamine Γ- (nonamethyltetrasiloxanyl) dimethylsilylpropylamine, 6-tris (trimethylsiloxy) silylhexylamine, 6-
Bis (trimethylsiloxy) methylsilylhexylamine, 6- (trimethylsiloxy) dimethylsilylhexylamine, 10-tris (trimethylsiloxy) silyldecylamine, 10-bis (trimethylsiloxy) methylsilyldecylamine, 10- (trimethylsiloxy)
Dimethylsilyldecylamine and the like.

Such an amino group-containing siloxane compound can be obtained by a known method without any particular limitation, and is described in, for example, JP-A-6-228161 and shown in the following formula (4). So that

[0039]

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(Wherein R ^{1 to} R ⁷ , n and a have the same meanings as above, and R ⁹ represents an organic group having 1 to 4 carbon atoms). It can be obtained by a dealcoholization reaction by transesterification with silanol. In addition, it is also possible to obtain as an industrial raw material.

The diaryl carbonate used in the reaction with the amino-containing siloxane compound in the first step is represented by the general formula (5).

[0042]

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(Wherein, Ar ¹ and Ar ² are the same or different and represent an aryl group.) The aryl group represented by Ar ¹ and Ar ² is, for example, a phenyl group, for example, a methyl group, an ethyl group , An alkylphenyl group having an alkyl substituent such as a propyl group or a butyl group, for example, a halogenated phenyl group having a halogen substituent such as fluorine, chlorine, bromine, or iodine, for example, a methoxy, ethoxy, propoxy, butoxy group, etc. And a phenyloxy group having a substituent such as a phenoxy group, for example, an arylphenyl group having a substituent such as an aryl group. Preferably, a phenyl group is used, and more specifically, diphenyl carbonate is used.

In the first step, the ratio of reacting the amino group-containing siloxane compound with the diaryl carbonate is 1 to 20 mol, particularly 1 to 10 mol, of the diaryl carbonate per 1 mol of the amino group-containing siloxane compound. Is preferred. If it is less than 1 mol, unreacted amino groups remain, and if it is more than 20 mol, it is not practical from an economic viewpoint.

The reaction of the amino group-containing siloxane compound with the diaryl carbonate is carried out at a reaction temperature in the range of 0 ° C. to the boiling point of the reaction product obtained by this reaction at normal pressure or under pressure. can do. More specifically, the reaction is carried out at 30-160 ° C.
It is preferable to carry out within the range.

In the reaction in the first step, the use of a solvent is optional. However, if an inert solvent preferably used in the second step described later is used as a solvent for this reaction, the solvent in the first step can be used. The obtained reaction product liquid can be used as it is as the decomposition stock solution in the second step, and efficient production can be performed.

The reaction of the amino group-containing siloxane compound with the diaryl carbonate gives a compound of the general formula (2)

[0048]

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(Wherein, R ^{1 to} R ⁷ , n and a have the same meanings as described above, and R ⁸ represents an aryl group).

As the aryl group represented by R ⁸ , for example, those similar to the aryl groups represented by Ar ¹ and Ar ² can be mentioned.

Examples of such an aryl group-containing siloxane compound having a carbamate group include, for example, those corresponding to the above-mentioned amino group-containing siloxane compounds more specifically. For example, γ-tris (trimethylsiloxy) silylpropyl Phenyl carbamate, γ-bis (trimethylsiloxy) methylsilylpropylphenylcarbamate, γ- (trimethylsiloxy) dimethylsilylpropylcarbamate, γ-tris (pentamethyldisiloxanyl) silylpropylcarbamate, γ- Phenyl bis (pentamethyldisiloxanyl) methylsilylpropylcarbamate, phenylγ- (pentamethyldisiloxanyl) dimethylsilylpropylcarbamate, γ-tris (heptamethyltrisiloxanyl) silylpropionate Phenyl carbamate, .gamma.
Phenyl bis (heptamethyltrisiloxanyl) methylsilylpropylcarbamate, phenylγ- (heptamethyltrisiloxanyl) dimethylsilylpropylcarbamate, γ-tris (nonamethyltetrasiloxanyl)
Phenyl silylpropylcarbamate, phenyl γ-bis (nonamethyltetrasiloxanyl) methylsilylpropylcarbamate, phenylγ- (nonamethyltetrasiloxanyl) dimethylsilylpropylcarbamate, 6
Phenyl tris (trimethylsiloxy) silylhexylcarbamate, phenyl 6-bis (trimethylsiloxy) methylsilylhexylcarbamate, phenyl 6- (trimethylsiloxy) dimethylsilylhexylcarbamate, 10-tris (trimethylsiloxy) silyldecylcarbamate Phenyl, 10-bis (trimethylsiloxy) methylsilyldecylcarbamate phenyl, 1
And phenyl 0- (trimethylsiloxy) dimethylsilyldecylcarbamate.

In the present invention, the aryl group-containing carbamic acid-containing siloxane compound thus obtained is thermally decomposed in the second step.

For this thermal decomposition, a known decomposition method such as a liquid phase method and a gas phase method can be used. Preferably, the liquid phase method, more specifically, an isocyanate group which is a decomposition product, is used. It is preferable to carry out the reaction by a reactive distillation method in which the contained siloxane compound and the aryl alcohol are separated out of the system. The pyrolysis reaction temperature is usually 350 ° C or lower, preferably 80 to 350 ° C, more preferably,
100-300 ° C. If it is lower than 80 ° C., a practical reaction rate may not be obtained, and if it is higher than 350 ° C., undesired side reactions such as polymerization of isocyanate may occur. Further, the pressure at the time of the thermal decomposition reaction is preferably a pressure at which the generated isocyanate group-containing siloxane compound and aryl alcohol can be vaporized with respect to the above-mentioned thermal decomposition reaction temperature. Is preferably 0.133 to 90 kPa.

The thermal decomposition is preferably carried out in the presence of an inert solvent having a higher boiling point than the isocyanate group-containing siloxane compound to be produced.
When an inert solvent is not used, the siloxane compound containing an aryl carbamate group and the siloxane compound containing an isocyanate group are present in a high concentration in the reaction system. In some cases, the resulting isocyanate group-containing siloxane compound cannot be obtained in high yield.

Such an inert solvent is at least inert to the carboxylate-containing aryl group-containing siloxane compound and the isocyanate group-containing siloxane compound. Is required to be inert to amino group-containing siloxane compounds and diaryl carbonate. The inert solvent is required to have a boiling point higher than that of the isocyanate group-containing siloxane compound. When the boiling point of the inert solvent is lower than the boiling point of the isocyanate group-containing siloxane compound, the inert solvent is vaporized during the thermal decomposition, and as described above, the generated isocyanate group-containing siloxane compound becomes high. Cannot be obtained in yield.

Examples of such an inert solvent include, for example,
At normal pressure (101.3 kPa) its boiling point is 250
To 550 ° C., more specifically, for example, esters such as dioctyl phthalate, didecyl phthalate, didodecyl phthalate, for example, dibenzyltoluene, phenylnaphthalene, biphenyl, diethylbiphenyl, triethylbiphenyl, hydrogen Aromatic or alicyclic hydrocarbons such as triphenyl chloride are used. Also, industrially, it is commonly used as a heat medium, for example, THERMS 600 (boiling point 286 ° C., manufactured by Nippon Steel Chemical Co., Ltd.), THERMS 700 (boiling point 315 ° C., manufactured by Nippon Steel Chemical Co., Ltd.) , Therms 800 (boiling point 340
℃, Nippon Steel Chemical Co., Ltd.), THERMS 900 (boiling point 3
64 ° C, Nippon Steel Chemical Co., Ltd.), THERMS 1000S
(Boiling point 387 ° C, manufactured by Nippon Steel Chemical Co., Ltd.), NeoSK-
OIL 1400 (boiling point 391 ° C., manufactured by Soken Chemical Co., Ltd.)
A commercially available high-boiling solvent such as NeoSK-OILL400 (boiling point: 440 ° C., manufactured by Soken Chemical Co., Ltd.) may be used.

The amount of the inert solvent to be used is 0.0 to 1 part by weight of the aryl group-containing carbamic acid-containing siloxane compound.
0.5 to 100 parts by weight, preferably 0.01 to 5 parts by weight.
0 parts by weight, and more practically 0.1%
It is in the range of ２０20 parts by weight. In addition, this usage amount is the first
The same applies to the case of using from the reaction of the step.

When an inert solvent is used in the second step, a batch reaction in which the aryl group-containing carbamic acid-containing siloxane compound and the inert solvent are charged at once, or a carbamic acid under reduced pressure in an inert solvent is used. It may be carried out by any method of a continuous reaction in which the aryl group-containing siloxane compound is charged.

In this thermal decomposition, for example, a known catalyst for decomposing a carbamic acid ester into isocyanate and alcohol may be appropriately used.

Then, by such thermal decomposition, the general formula (3)

[0061]

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(Wherein, R ^{1 to} R ⁷ , n, and a have the same meanings as described above).

Examples of such isocyanate group-containing siloxane compounds are, for example, more specifically corresponding to the above-mentioned aryl carbamate-containing siloxane compounds, for example, γ-tris (trimethylsiloxy) silylpropyl Isocyanate, γ-bis (trimethylsiloxy) methylsilylpropyl isocyanate, γ- (trimethylsiloxy) dimethylsilylpropyl isocyanate, γ-tris (pentamethyldisiloxanyl) silylpropyl isocyanate, γ-bis (pentamethyldisiloxanyl) ) Methylsilylpropyl isocyanate, γ- (pentamethyldisiloxanyl)
Dimethylsilylpropyl isocyanate, γ-tris (heptamethyltrisiloxanyl) silylpropyl isocyanate, γ-bis (heptamethyltrisiloxanyl) methylsilylpropyl isocyanate, γ- (heptamethyltrisiloxanyl) dimethylsilylpropyl isocyanate Γ-tris (nonamethyltetrasiloxanyl) silylpropyl isocyanate, γ-bis (nonamethyltetrasiloxanyl) methylsilylpropyl isocyanate, γ- (nonamethyltetrasiloxanyl) dimethylsilylpropyl isocyanate 6-tris (trimethylsiloxy) silylhexyl isocyanate, 6
-Bis (trimethylsiloxy) methylsilylhexyl isocyanate, 6- (trimethylsiloxy) dimethylsilylhexyl isocyanate, 10-tris (trimethylsiloxy) silyldecyl isocyanate, 10-bis (trimethylsiloxy) methylsilyldecyl isocyanate, 10- ( Trimethylsiloxy) dimethylsilyldecyl isocyanate.

The siloxane compound containing an isocyanate group produced in this manner has a high purity (for example, 95%).
% Or more) and a high yield (for example, 80% or more), and is useful as a high-quality industrial raw material. The isocyanate group-containing siloxane compound produced by such a production method has an intermediate product, an aryl carbamate-containing siloxane compound, of 0.00%.
1% by weight or more may be contained.

As described above, if a siloxane compound containing an isocyanate group is produced by such a production method, since phosgene is not used, it is necessary to safely treat the apparatus and to treat salts produced as a by-product. Since there is no siloxane compound, it is easy to industrialize, and a siloxane compound containing an isocyanate group can be obtained with high purity and high yield. Therefore, an isocyanate group-containing siloxane compound can be produced economically advantageously.

In the above description, the isocyanate group-containing siloxane compound is produced in the first step and the second step. However, in the production method of the present invention, a pretreatment step such as a dehydration step, an intermediate step, Alternatively, it may include a known step such as a post-treatment step such as a purification step and a recovery step.

[0067]

Example 1 (First step) 118.1 g (0.55 mol) of diphenyl carbonate (hereinafter abbreviated as DPC) was charged to a reflux condenser, a thermometer, a nitrogen blowing nozzle, a dropping funnel and stirring. A 500-ml glass four-necked flask (reactor) equipped with an apparatus was charged, and the inside of the flask was replaced with nitrogen. Then, the flask was placed in an oil bath adjusted to 60 ° C. When the liquid temperature in the flask reaches 60 ° C., γ
-150.0 g (0.423 mol) of tris (trimethylsiloxy) silylpropylamine was dropped into the flask from the dropping funnel.

After completion of the dropping, the temperature of the liquid in the flask was raised to 100 ° C.
, And reacted for 1 hour. The reaction product was a homogeneous solution. A part of the reaction product was sampled,
Potentiometric titration was performed with 1N hydrochloric acid. As a result, the conversion of γ-tris (trimethylsiloxy) silylpropylamine was 99% or more. Also, after separating the obtained reaction product using gel permeation chromatography,
By measuring NMR, the following data was obtained, and it was confirmed that the product was phenyl γ-tris (trimethylsiloxy) silylpropylcarbamate. Furthermore, as a result of quantifying the reaction product liquid by liquid chromatography (internal standard method), the yield of phenyl γ-tris (trimethylsiloxy) silylpropylcarbamate was 9%.
It was 8.6%.

H ¹ -NMR spectrum (CDCl ₃ , T
MS: ppm): 7.53,7.18,7.12ppm (t , 2H t, 2H d, 2H; -OC 6 H 5) 5.14ppm (s, 1H; -C-NH-CO-) 3.30ppm (q, 2H; -C-CH ₂ -N-) 1.60 ppm (m, 2H; -C-CH ₂ -C-) 0.50 ppm (t, 2H; -Si-CH ₂ -C-) 0.05 ppm (s, 27H; (( CH ₃ ) ₃ SiO) ₃ -Si-) (Second step) A capacity of 500 equipped with a capillary, a thermometer, a reaction liquid extraction nozzle and a rectification column with a fractionating head.
A three-neck ml flask was used as the reactor. A receiver and a cooler were attached to the fractionation head. Hot water at 80 ° C. was passed through the cooler, and the receiver was connected to a vacuum line via a cold trap cooled with cold ethanol.

In a flask, 250.0 g of the reaction product liquid obtained in the first step, and 100.0 g of THERMSS 1000S (inert solvent, boiling point: 387 ° C., manufactured by Nippon Steel Chemical Co., Ltd.)
And the flask was placed in an oil bath.
After the atmosphere in the flask was replaced with nitrogen, the pressure was reduced to 2.67 kPa, the temperature of the oil bath was raised to 200 ° C., and a thermal decomposition reaction was performed for 2 hours. After completion of the reaction, the reaction solution collected in the receiver was quantified by gas chromatography. As a result, the obtained γ-tris (trimethylsiloxy) silylpropyl isocyanate had a purity of 96.5% and a yield of 89.2%. Was. In the reaction solution after the reaction and in the flask, no suspended or adhered solids were found, and even when cooled to 25 ° C., no solids were seen.

The content of phenyl γ-tris (trimethylsiloxy) silylpropylcarbamate in the obtained γ-tris (trimethylsiloxy) silylpropyl isocyanate was determined by NMR to be 2.2% by weight. This quantification is based on the integrated value a of the peak derived from the phenyl group a [7.35, 7.18, 7.12 ppm (t, 2Ht, 1Hd, 2
H; -OC ₆ H ₅ )] and the integrated value b [0.50 ppm (t, 2H; -Si-CH ₂ -C-)] of the peak derived from methylene adjacent to silicon, (a / 5) / (B / 2) × 100 was calculated and calculated in terms of molecular weight.

Example 2 (First step) 11.1 g (0.55 mol) of DPC
And 100 g of THERMES 1000S were charged into a flask, and a reaction was performed in the same manner as in the first step of Example 1 below. The obtained reaction product liquid was a homogeneous solution. A part of the reaction solution was sampled and subjected to potentiometric titration with 0.1N hydrochloric acid. As a result, the reaction rate of γ-tris (trimethylsiloxy) silylpropylamine was 99%.
% Or more. (Second step) A flask was charged with 350.0 g of the reaction product liquid obtained in the first step.
A thermal decomposition reaction was carried out in the same manner as in Example 1 except that 0S was not charged. After completion of the reaction, the reaction solution collected in the receiver was quantified by gas chromatography. As a result, the obtained γ-tris (trimethylsiloxy) silylpropyl isocyanate had a purity of 97.1% and a yield of 93.2%. Was. In the reaction solution after the reaction and in the flask, no suspended or adhered solids were found, and even when cooled to 25 ° C., no solids were seen.

Example 3 (First Step) The reaction was carried out in the same manner as in the first step of Example 1 to obtain a reaction product. The obtained reaction product liquid was a homogeneous solution. A part of the reaction solution was sampled and subjected to potentiometric titration with 0.1N hydrochloric acid. as a result,
The conversion of γ-tris (trimethylsiloxy) silylpropylamine was 99% or more. (Second step) A flask was charged with 350.0 g of the reaction product liquid obtained in the first step.
A thermal decomposition reaction was carried out in the same manner as in Example 1 except that 0S was not charged and the pressure in the flask was 13 kPa. After the completion of the reaction, the reaction solution collected in the receiver was quantified by gas chromatography. As a result, the obtained γ-tris (trimethylsiloxy) silylpropyl isocyanate was 97.1% pure and 8 in yield.
1.0%.

Comparative Example 1 (First Step) In a flask constructed in the same manner as in the first step of Example 1, 49.6 g of dimethyl carbonate (hereinafter abbreviated as DMC) instead of 18.1 g of DPCl.
(0.55 mol), and γ-
Tris (trimethylsiloxy) silylpropylamine 1
50.0 g (0.423 mol) was dropped into the flask from the dropping funnel. After completion of the dropping, the liquid temperature in the flask is set to 7
The temperature was raised to 0 ° C., and the reaction was performed for 5 hours. A part of the reaction solution was sampled and subjected to potentiometric titration with 0.1N hydrochloric acid. As a result, the reaction rate of γ-tris (trimethylsiloxy) silylpropylamine was 0%.

Comparative Example 2 (First Step) Known (eg, US Pat. No. 5,211)
No. 8,133), and the reaction was carried out according to a method for converting an alkoxysilyl group-containing amine into a carbamic acid ester using DMC to obtain a reaction product.

That is, in a flask constructed in the same manner as in the first step of Example 1, 49.6 g (0.55 m
ol), 150.0 g (0.42 mol) of γ-tris (trimethylsiloxy) silylpropylamine,
After the atmosphere in the flask was replaced with nitrogen, the flask was placed in an oil bath adjusted to 50 ° C. When the liquid temperature in the flask reaches 50 ° C., 28% of sodium methylate
8.2 g (0.042 mol) of the solution was dropped from a dropping funnel to 5 g.
It was divided and dropped into the flask. After the completion of the dropwise addition, the liquid temperature in the flask was raised to 70 ° C., and the reaction was performed for 5 hours. A part of the reaction solution was sampled and subjected to potentiometric titration with 0.1N hydrochloric acid. As a result, the reaction rate of γ-tris (trimethylsiloxy) silylpropylamine was 61.9.
%Met. (Second Step) In a flask constructed in the same manner as in the second step of Example 1, 200 g of a solution obtained by neutralizing the reaction product liquid obtained in the first step with phosphoric acid, and 1000 mg of THERMES
00.0 g, and the flask was placed in an oil bath. After replacing the atmosphere in the flask with nitrogen, 2.67 kP
When the pressure was reduced to a and the temperature of the oil bath was raised to 250 ° C., a large amount of air bubbles were generated in the flask, so that it was impossible to continue the reaction, and the thermal decomposition reaction was stopped.

[0077]

According to the production method of the present invention, since phosgene is not used, it is safe, and there is no need to treat the equipment or treat salts produced as a by-product. An isocyanate group-containing siloxane compound can be obtained at a high yield. Therefore, an isocyanate group-containing siloxane compound can be produced economically advantageously. In particular, if an inert solvent having a boiling point higher than that of the isocyanate group-containing siloxane compound is used in the second step, the yield can be further improved.

The isocyanate group-containing siloxane compound thus produced is useful as a high-quality industrial raw material because of its high purity and high yield.

The aryl carbamate-containing siloxane compound obtained in the first step of the present invention is
It is useful as an intermediate for producing the isocyanate group-containing siloxane compound of the present invention.

Continuing from the front page (72) Inventor Takashi Uchida Inside the Chemicals Company, Takeda Pharmaceutical Co., Ltd. 2--17-18 Honcho, Yodogawa-ku, Osaka-shi, Osaka (72) Inventor Fumiaki Hirata Ju, Yodogawa-ku, Osaka-shi, Osaka 2-17-17, Mihonmachi Takeda Pharmaceutical Company Limited F-term (reference) in Chemicals Company 4H049 VN01 VP02 VP03 VP04 VQ01 VQ02 VQ20 VQ21 VR21 VR22 VR23 VR41 VR42 VR43 VR44 VS01 VS02 VS20 VS21 VU36 VV02 VV09 VW01 VW02

Claims (5)

[Claims] 1. A compound of the general formula (1)(Where R¹, R^Two, R^ThreeIs an organic group having 1 to 8 carbon atoms or
Is -SiOR^FiveR⁶R⁷A siloxy group (R^Five,
R⁶, R⁷Is a hydrocarbon group having 1 to 8 carbon atoms), ^FourIs charcoal
An organic group having a prime number of 1 to 8, n is an integer of 1 to 10, and a is
Indicates 0, 1 or 2. ) Amino group containing silo
The xanth compound is reacted with a diaryl carbonate to form a compound of the general formula
(2)(Where R¹~ R⁷, N and a are as defined above.
Then R⁸Represents an aryl group. ) Carbamine
A first step of obtaining an acid aryl group-containing siloxane compound;
Aryl carbamate-containing siloxy obtained in the first step
By thermally decomposing the sun compound, the compound represented by the general formula (3)(Where R¹~ R⁷, N and a are as defined above.
You. ) Isocyanate group-containing siloxane compound
A second step of obtaining a product.
A method for producing a siloxane compound containing a cyanate group. 2. In the second step, thermal decomposition is carried out in the presence of an inert solvent having a boiling point higher than that of the isocyanate group-containing siloxane compound represented by the general formula (3) obtained by thermal decomposition. Characterized in that
A method for producing the isocyanate group-containing siloxane compound according to claim 1. 3. A compound of the general formula (2)(Where R¹, R^Two, R^ThreeIs an organic group having 1 to 8 carbon atoms or
Is -SiOR^FiveR⁶R⁷A siloxy group (R^Five,
R⁶, R⁷Is a hydrocarbon group having 1 to 8 carbon atoms), ^FourIs charcoal
An organic group having a prime number of 1 to 8 is represented by R⁸Represents an aryl group, and n represents 1 to
A represents 0, 1 or 2; )
, A siloxane compound containing an aryl carbamate. 4. A compound of the general formula (1)(Where R¹, R^Two, R^ThreeIs an organic group having 1 to 8 carbon atoms or
Is -SiOR^FiveR⁶R⁷A siloxy group (R^Five,
R⁶, R⁷Is a hydrocarbon group having 1 to 8 carbon atoms), ^FourIs charcoal
An organic group having a prime number of 1 to 8, n is an integer of 1 to 10, and a is
Indicates 0, 1 or 2. ) Amino group containing silo
By reacting a xanse compound with a diaryl carbonate
General formula (2) obtained by(Where R¹~ R⁷, N and a are as defined above.
Then R⁸Represents an aryl group. ) Carbamine
Thermally decomposing a siloxane compound containing an aryl aryl group
General formula (3) obtained by(Where R¹~ R⁷, N and a are as defined above.
You. ) Isocyanate group-containing siloxane compound
object. 5. A compound of the general formula (2)(Where R¹, R^Two, R^ThreeIs an organic group having 1 to 8 carbon atoms or
Is -SiOR^FiveR⁶R⁷A siloxy group (R^Five,
R⁶, R⁷Is a hydrocarbon group having 1 to 8 carbon atoms), ^FourIs charcoal
An organic group having a prime number of 1 to 8, n is an integer of 1 to 10, and a is
Indicates 0, 1 or 2. Ali) carbamate represented by)
At least 0.001% by weight of a siloxane compound having a hydroxyl group.
The isocyanate according to claim 4, wherein
Anate group-containing siloxane compounds.