JP3419165B2 - New alkoxysilane compounds suitable for coating inorganic powders - Google Patents

Description

Detailed Description of the Invention

[0001]

TECHNICAL FIELD The present invention relates to a novel alkoxysilane compound having a sulfonic acid ester group, and an inorganic substance, particularly an inorganic powder, having a coating formed from this alkoxysilane on its surface. This coated inorganic powder is useful as a solid alkylating agent.

[0002]

BACKGROUND OF THE INVENTION Alkyl esters of sulfonic acids, especially aromatic sulfonic acid alkyl esters such as p-toluenesulfonic acid and naphthalenesulfonic acid are important reagents as alkylating agents and are often used in organic synthesis. There is.

[0003]

When using a sulfonic acid alkyl ester as an alkylating agent, it is necessary to separate the sulfonic acid or its salt by-produced in the alkylation reaction from the reaction solution containing the alkylation product. . However, in general, organic sulfonic acids have a problem that it is difficult to separate them from the reaction solution due to their high solubility in the organic solvent used for the alkylation reaction and their surfactant-like properties.

An object of the present invention is to provide a solid alkylating agent which can be easily separated from the reaction solution after the alkylation reaction by filtration or the like in order to solve the above problems.
Another object of the present invention is to provide new alkoxysilane compounds for use in the preparation of this solid alkylating agent.

[0005]

Means for Solving the Problems The present inventors have found that a powder obtained by coating an inorganic powder with a novel alkoxysilane compound containing a sulfonic acid ester group is useful as a solid alkylating agent insoluble in organic solvents. Therefore, they have found that they can be easily separated from the reaction solution even after the alkylation reaction, and completed the present invention.

The present invention has the following gist. An alkoxysilane compound containing a sulfonate group represented by the following general formula (I).

[0007]

[Chemical 2]

In the above formula, R ¹ is an alkyl group having 1 to 6 carbon atoms, R ² is an alkyl group having 1 to 3 carbon atoms or a phenyl group,
R ³ is an alkyl group having 1 to 18 carbon atoms, Y is a phenylene group, m
Is an integer of 1 to 3, n is an integer of 0 to 2 (provided that m + n =
3), p is 2 or 3.

An inorganic powder having on its surface a coating formed from the alkoxysilane compound described in 1 above. A solid alkylating agent comprising the above-mentioned inorganic powder.

[0010]

BEST MODE FOR CARRYING OUT THE INVENTION A preferred alkoxysilane compound of the present invention has the general formula (I) wherein R ¹ is methyl, ethyl or propyl, R ² is methyl or ethyl, and p is 2, A compound in which R ³ is an alkyl group having 1 to 8 carbon atoms.

In the general formula (I), each alkyl group of R ^{1 to} R ³ may be linear or branched. R ² phenyl group and Y
The phenylene group may have a substituent such as halogen or hydroxy on the benzene ring. Further, a sulfonic acid ester group (-SO ₃ R ³ groups) are on Y of the benzene ring - (C
H ₂₎ p-can be present in any position relative to the chain, but preferably the meta or para position, more preferably the para position.

As shown in the above general formula, in the alkoxysilane compound of the present invention, the sulfonic acid alkyl ester group which is a terminal functional group has an alkoxysilyl group (1 to 3 alkoxyl groups on silicon and an alkyl group through a phenylalkylene chain). It has a chemical structure similar to that of a silane coupling agent, which is bonded to a group in which 0 to 2 groups are bonded.

The alkoxysilane compound of the present invention can be synthesized by utilizing a known chemical reaction, and the synthesis method is not particularly limited. For example, a compound of the general formula (I) in which p is 2 is prepared by esterifying the starting styrene sulfonyl chloride and reacting the obtained styrene sulfonate with trichlorosilane or alkylchlorosilane as shown in the following formula A: And alkoxylation of the chlorosilyl group. Also, the general formula
When the R ¹ group and the R ³ group in (I) are the same alkyl group, styrenesulfonyl chloride is directly reacted with trichlorosilane or alkyltrichlorosilane as shown in formula B, and then the chlorosilyl group is alkoxylated. At the same time, it can be synthesized by a method in which the terminal sulfonyl chloride group is esterified. When p is 3, allylbenzenesulfonyl chloride may be used as the starting material for these methods. The halogen of the above compounds may be bromine instead of chlorine.

[0014]

[Chemical 3]

The addition reaction of trichlorosilane or alkylchlorosilane [HSi (Cl) m (R ² ) n] generally requires a catalyst such as chloroplatinic acid. Further, the alkoxylation reaction of the chlorosilyl group and the esterification of the sulfonyl chloride group are carried out by reacting the corresponding alcohol or metal alkoxide. When alcohol is reacted, the reaction is carried out in the presence of an organic solvent and an acid scavenger such as a tertiary amine in order to remove by-produced hydrogen chloride. If water is mixed in the alcohol or solvent to be used, decomposition or condensation of the product occurs, so it is preferable to use a sufficiently dehydrated product. The dehydrating agent is not particularly limited, but molecular sieves are generally preferred because of their high dehydrating ability. A polar solvent such as ether or ketone is suitable as the organic solvent.

The reaction temperature in any of the above reactions is not particularly limited, but is usually carried out in the temperature range from room temperature to the boiling point of the solvent. After completion of the reaction, isolation / purification of the product is carried out by distillation, extraction, filtration (eg, separation of by-produced amine hydrohalide salt) and the like according to a conventional method.

When the alkoxysilane compound having a sulfonic acid ester group of the present invention is used for the surface treatment of an inorganic powder, the alkoxysilyl group interacts with the hydroxyl group present on the surface of the inorganic powder, as in the conventional silane coupling agent. Acting, the alkoxyl group hydrolyzes into a hydroxyl group in the presence of moisture (e.g., moisture in the atmosphere), and the hydroxyl group undergoes a condensation reaction with the hydroxyl group on the surface of the inorganic powder, whereby the alkoxysilane compound is It binds to the surface of the inorganic powder. This bond becomes stronger by heating after the surface treatment.

When the inorganic powder is thus coated with the alkoxysilane compound of the present invention, the sulfonic acid ester group bonded to the other end of the molecule comes to exist on the surface layer side of the coating. That is, a large number of sulfonic acid ester groups (more specifically, alkylenebenzenesulfonic acid ester groups) are present on the surface of the powder, and the sulfonic acid ester groups are firmly fixed to the powder. Due to this structure, this powder functions as a solid alkylating agent.

The type of inorganic powder used for the surface treatment is not particularly limited. For example, silica, titanium oxide (titania)
, Alumina, Zinc oxide, and other metal oxides, Complex metal oxides containing two or more metals (including various silicate minerals)
Examples thereof include metal hydroxides such as aluminum hydroxide, sulfides such as zinc sulfide, and insoluble metal salts such as calcium carbonate and calcium sulfate, but other substances can also be used. The average particle size of the inorganic powder is also not particularly limited, but a range of 0.10 to 1 μm is preferable. Since powder has a large specific surface area, it is appropriate to use powder for the surface treatment, but it goes without saying that other forms of inorganic substances such as fibrous substances can also be used. Further, an organic powder can be used as long as it has a hydroxyl group on the surface. Examples of such organic powders include powders of cellulose, epoxy resin, phenol resin and the like. However, here, the material used for the surface treatment is represented by an inorganic powder.

The surface treatment of the inorganic powder may be either wet or dry. The wet surface treatment can be carried out by immersing the inorganic powder in a solution in which the alkoxysilane compound of the present invention is dissolved in a suitable solvent, and then distilling off the excess solvent. The dry surface treatment can be carried out, for example, by stirring the inorganic powder in a floating state and dropping or spraying a solution of the alkoxysilane compound of the present invention dissolved in a suitable solvent thereto. In any case, it is preferable to heat after the surface treatment in order to firmly bond the alkoxysilane compound with the inorganic substance.

The heating temperature and time may be set so that the solvent used is completely removed, the alkoxysilane compound is firmly bonded to the inorganic powder, and the sulfonic acid ester is present in a stable manner. However, a temperature range of 40-80 ° C is generally preferred. To prevent the oxidation of the alkoxysilane compound during heating, heat it with an inert gas.
It is preferable to carry out in an atmosphere (eg, nitrogen, argon, helium, etc.).

The amount of the above-mentioned alkoxysilane compound to be coated on the surface of the inorganic substance is not particularly limited as long as the necessary amount of the sulfonic acid ester group as an alkylating agent is bonded to the surface, but it is 1 to 60% by weight of the powder weight. %, Especially 5 to 40% by weight is preferred. If it is less than 1% by weight, the amount of surface coating is small and it does not function sufficiently as an alkylating agent.
On the other hand, if it exceeds 60% by weight, there is a possibility that problems such as the whole coating not being bonded to the surface of the inorganic powder may occur.

The inorganic powder surface-treated with the alkoxysilane compound represented by the general formula (I) in this manner has a large number of sulfonic acid ester groups on its surface,
It can be used as a solid alkylating agent. The alkylation reaction is carried out by stirring the powder of the alkylating agent in a solution in which a material to be alkylated (eg, organic primary or secondary amine) is dissolved with heating, if necessary.
Due to the reaction, the sulfonic acid ester group bound to the powder changes to a free sulfonic acid group (-SO ₃ H group), but this sulfonic acid group is also bound to the powder, so it does not dissolve in the solution (reaction solution). . Therefore, after the reaction, unreacted and reacted alkylating agent can be easily separated from the reaction solution by filtration or the like.
Can be collected. The recovered alkylating agent powder is
It can be regenerated by reacting it with an alcohol or a metal alkoxide to esterify it.

[0024]

【Example】

Example 1 Synthesis of (CH ₃ O) ₃ SiCH ₂ CH ₂ (C ₆ H ₄ ) SO ₃ CH ₂ CH (CH ₃ ) ₂ 50 equipped with a mechanical stirrer, thermometer, reflux device, dropping funnel
In a 0 ml three-necked flask, 14.8 g of isobutyl alcohol, 300 ml of diisopropyl ether as a solvent, and 30.3 g of triethylamine as an acid scavenger were put, and while cooling to 20 ° C or lower, 4-styrenesulfonyl chloride [CH ₂ = CH
20.2 g of (C ₆ H ₄ ) SO ₂ Cl] was added dropwise over 1 hour. After completion of the dropping, the mixture was heated to 50 ° C. and stirred for 3 hours. After completion of stirring, the reaction solution was poured into a large excess of dilute hydrochloric acid aqueous solution, and the solution was separated and washed with water, the oil layer was dried over anhydrous sodium sulfate, and then filtered, and then excess diisopropyl ether was distilled off under reduced pressure to give 4-styrene. Sulfonic acid isobutyl ester [CH ₂ =
17.5 g of CH (C ₆ H ₄ ) SO ₃ CH ₂ CH (CH ₃ ) ₂ ] was obtained as an oil.
(Yield 78%).

Next, 15.0 g of the above oily product was placed in a 50 ml three-necked flask equipped with a magnetic stirrer, a thermometer, a dropping funnel, and a reflux condenser, and nitrogen was blown thereinto at room temperature for 2 hours.
Then, 10 mg of chloroplatinic acid was added, and while maintaining the temperature at 85 ° C, trichlorosilane [HSiCl ₃ ] 9.0 g was added from the dropping funnel.
Was added dropwise over 1 hour. After completion of dropping, the mixture was stirred at the same temperature for 2 hours, and p-isobutyroxysulfonylphenylethyltrichlorosilane [Cl ₃ SiCH ₂ CH ₂ (C ₆ H ₄ ) SO ₃ CH ₂ CH (C
H _{3) 2]} was obtained 22.9g as an intermediate product (95% yield). The elemental analysis result, IR spectrum (only characteristic peaks, the same applies hereinafter) and NMR spectrum of this intermediate product were as follows.

[0026] IR: 3050 ~ 2880, 1351, 1176cm ^-1 1H-NMR: δ (ppm) = 0.65 (m, 2H), 1.32 (d, 2H), 1.45 (m, 2
H), 1.55 (m, 6H), 4.65 (d, 2H), 7.4-7.8 (m, 4H).

A 500 ml three-necked flask equipped with a reflux condenser and a dropping funnel was charged with 20 g of methanol, 200 ml of diisopropyl ether as a solvent and 60 g of triethylamine as an acid scavenger, and the Cl ₃ SiCH ₂ CH ₂ (C ₆₎ obtained above was added thereto. A solution of 22.9 g of H ₄ ) SO ₃ C (CH ₃ ) _{3 in} 100 ml of diisopropyl ether was added dropwise at a temperature of 20 ° C. or lower over 2 hours. After completion of the dropping, the mixture was further stirred at room temperature for 3 hours, and then diisopropyl ether and excess methanol and triethylamine were distilled off under reduced pressure. The residual liquid was dissolved in 300 ml of hexane and left overnight. Next, the formed precipitate was filtered, the filtrate was decolorized with activated carbon, and then hexane was distilled off under reduced pressure to obtain 22.0 g of the title compound (p-isobutyroxysulfonylphenylethyltrimethoxysilane) (yield 90%. ).

[0028] IR: 3050 ~ 2880, 1351, 1176, 1080cm ^-1 1H-NMR: δ (ppm) = 0.63 (m, 2H), 1.33 (d, 2H), 1.45 (m, 2
H), 1.54 (m, 6H), 3.60 (s, 9H), 4.69 (d, 2H), 7.4-7.8
(m, 4H).

Example 2 Synthesis of (CH ₃ CH ₂ O) ₃ SiCH ₂ CH ₂ (C ₆ H ₄ ) SO ₃ CH ₂ CH ₃ 50 equipped with a magnetic stirrer, thermometer, dropping funnel, and reflux device
4-Styrenesulfonyl chloride in 3 ml three-necked flask
20.2 g was added and nitrogen was blown in at room temperature for 2 hours. Then, 10 mg of chloroplatinic acid was added thereto, the temperature was kept at 85 ° C., and 13.5 g of trichlorosilane was added dropwise from the dropping funnel over 1 hour. After completion of dropping, the mixture was stirred at the same temperature for 2 hours, and p-chlorosulfonylphenylethyltrichlorosilane [Cl ₃ SiCH ₂ CH ₂ (C ₆ H ₄ ) SO ₂ Cl] 32.7 was obtained as an intermediate product.
g was obtained (yield 97%).

Next, 500 ml equipped with a reflux condenser and a dropping funnel
To a three-necked flask, 40 g of ethanol, 250 ml of diisopropyl ether as a solvent, and 121 g of triethylamine as an acid scavenger were placed, and the intermediate product [Cl ₃ SiCH ₂ CH ₂ (C ₆ H ₄ ) S] obtained above was placed in the flask.
A solution of 32.7 g of O ₂ Cl] dissolved in 100 ml of diisopropyl ether was added dropwise at a temperature of 20 ° C. or lower over 2 hours. After completion of the dropping, the mixture was further stirred at room temperature for 3 hours, and then diisopropyl ether and excess methanol and triethylamine were distilled off under reduced pressure. Dissolve the residual liquid in 300 ml of hexane,
I left it overnight. Then, the formed precipitate was filtered, the filtrate was decolorized with activated carbon, and then hexane was distilled off under reduced pressure to obtain 30.9 g of the title compound (p-ethoxysulfonylphenylethyltriethoxysilane) (yield 85%).

[0031] IR: 3050 to 2880, 1351, 1176, 1080cm ^-1 1H-NMR: δ (ppm) = 0.66 (m, 2H), 1.21 (t, 9H), 1.25 (t, 3
H), 3.79 (q, 6H), 3.83 (q, 3H), 7.4-7.8 (m, 4H).

Example 3 Synthesis of [(CH ₃ ) ₂ CHO] ₂ Si (CH ₃ ) CH ₂ CH ₂ (C ₆ H ₄ ) SO ₃ CH (CH ₃ ) _{2 In} Example 2, the intermediate product In the same manner except that 11.5 g of methyldichlorosilane was used in place of trichlorosilane in the synthesis step of, and 60 g of 2-propanol was used in place of ethanol in the next reaction, the title compound (p-isopropoxysulfonylphenylethyldiethyl) was used. 26.3 g of isopropoxymethylsilane) was obtained.

[0033] IR: 3050-2880, 1351, 1176, 1080cm ^-1 1H-NMR: δ (pp
m) = 0.12 (s, 3H), 0.67 (m, 2H), 1.15 (d, 12H), 1.18 (d,
6H), 1.45 (m, 2H), 3.88-3.92 (m, 3H) 7.4-7.8 (m, 4H)
.

[0034] (Example 4) In _{(CH 3 O) Si (CH} 3) 2 CH 2 CH 2 (C 6 H 4) SO 3 Synthesis Example 2 of CH _3, trichlorosilane in the synthesis stage of the intermediate product 9.5 g of dimethylchlorosilane was used instead, and 30 g of methanol was used instead of ethanol in the next reaction.
In the same manner except that was used, the title compound (p-methoxysulfonylphenylethylmethoxydimethylsilane) 2
0.1 g was obtained.

[0035] IR: 3050 to 2880, 1351, 1176, 1080cm ^-1 1H-NMR: δ (ppm) = 0.11 (s, 6H), 0.64 (m, 2H), 1.48 (m, 2
H), 3.61 (s, 3H), 3.68 (s, 3H), 7.4-7.8 (m, 4H).

[0036] (Example _{5) (CH 3 O) 3} SiCH 2 CH 2 (C 6 H 4) SO 3 CH 2 Synthesis Example 1 (CH _{2) 8} CH _3, of tert- butanol instead n- Similarly, 4-styrene sulfonyl chloride was esterified with decanol [C ₁₀ H ₂₁ OH] 31.6 g to give 4-styrene sulfonic acid decyl ester [CH ₂ = CH (C ₆ H ₄ ) SO ₃ CH ₂ (CH ₂ ). ₈ C
H ₃ ], which was then reacted with trichlorosilane as in Example 1 to give p-decyloxysulfonylphenylethyltrichlorosilane [Cl ₃ SiCH ₂ CH
_{2 (C 6 H 4) SO 3} CH 2 (CH 3) 8 CH 3] was obtained as an intermediate product.

[0037] IR: 3050-2880, 1351, 1176cm ^-1 1H-NMR: δ (ppm) = 0.64 (m, 2H), 0.91 (t, 3H), 1.22 (m, 1
6H), 1.46 (m, 2H), 3.80 (t, 2H), 7.4-7.8 (m, 4H).

Then, this intermediate product is reacted with methanol in the same manner as in Example 1 to methoxylate, to give the title compound.
(p-decyloxysulfonylphenylethyltrimethoxysilane) was obtained.

[0039] IR: 3050 ~ 2880, 1351, 1176, 1080cm ^-1 1H-NMR: δ (ppm) = 0.64 (m, 2H), 0.91 (t, 3H), 1.22 (m, 1
6H), 1.46 (m, 2H), 3.61 (s, 9H), 3.80 (t, 2H), 7.4-7.8
(m, 4H).

Example 6 Silica powder having an average particle size of 12 nm
(Aerosil # 200: manufactured by Nippon Aerosil Co., Ltd.) 20 g of the alkoxysilane compound obtained in Example 2 was placed in a juicer mixer while stirring so as to be in a floating state.
A solution prepared by dissolving 3.0 g in 3.0 g of hexane was added dropwise over 2 minutes. After completion of dropping, transfer the powder to a 1 liter separable flask and stir under nitrogen stream at 60 ° C for 3 hours.
After heating for a period of time, the surface of the silica powder was coated with the above alkoxysilane compound. The coating amount is 14% by weight of the powder weight.
Met.

Example 7 Example 6 using 20 g of titanium oxide powder having an average particle size of 21 nm (p-25: manufactured by Nippon Aerosil Co., Ltd.)
The same operation as above was carried out to obtain a titanium oxide powder whose surface was coated with an alkoxysilane compound (amount of coated powder =
14% by weight).

Example 8 Alumina powder having an average particle size of 13 nm
(Aluminum Oxide C: manufactured by Nippon Aerosil Co., Ltd.) The same operation as in Example 6 was carried out using 20 g to obtain an alumina powder whose surface was coated with an alkoxysilane compound (coating amount of powder = 14% by weight).

Example 9 In a 200 ml three-necked flask equipped with a mechanical stirrer, a thermometer and a reflux condenser, 10 g of the surface-coated silica powder obtained in Example 6 and 100 m of diisopropyl ether as a solvent were added.
l, n-Hexylamine (0.2 g) was added, and the mixture was refluxed with a solvent to give 1
The mixture was heated and stirred for one day. Then, the powder was separated by filtration and the gas chromatographic analysis of the filtrate was carried out. As a result, the amount of n-hexylamine was reduced to 1/4, and diethyl-n-hexylamine and ethyl-n-hexylamine were produced. Was confirmed.

Example 10 Using the surface-coated titanium oxide powder obtained in Example 7, the same operation as in Example 9 was performed. n-
It was confirmed that the amount of hexylamine decreased to 1/4 and that diethyl-n-hexylamine and ethyl-n-hexylamine were produced.

Example 11 Using the surface-coated alumina powder obtained in Example 8, the same operation as in Example 9 was performed. It was confirmed that the amount of n-hexylamine decreased to 1/4 and that diethyl-n-hexylamine and ethyl-n-hexylamine were produced.

[0046]

INDUSTRIAL APPLICABILITY The present invention provides a novel alkoxysilane compound having a sulfonic acid ester group at the molecular end, and an inorganic powder having a coating formed from this alkoxysilane compound on the surface is prepared from a reaction solution after an alkylation reaction. It is useful as a solid alkylating agent that can be easily separated.

─────────────────────────────────────────────────── ─── Continuation of front page (51) Int.Cl. ⁷ Identification code FI // C01G 23/04 C01G 23/04 Z (72) Inventor Hideaki Sakurai 1-297 Kitabukurocho, Omiya-shi, Saitama Sanritsu Material (56) References JP-A-5-88372 (JP, A) JP-A-1-266184 (JP, A) JP-A-9-110885 (JP, A) (58) Fields investigated ( Int.Cl. ⁷ , DB name) C07F 7/00 CA (STN) REGISTRY (STN)

Claims (3)

(57) [Claims] 1. An alkoxysilane compound containing a sulfonate group represented by the following general formula (I). [Chemical 1] In the formula, R ¹ is an alkyl group having 1 to 6 carbon atoms, and R ² is 1 to 6 carbon atoms.
An alkyl group of 3 or a phenyl group, R ³ is an alkyl group having 1 to 18 carbon atoms, Y is a phenylene group, m is an integer of 1 to 3, n
Is an integer of 0 to 2 (m + n = 3), and p is 2 or 3.
Is. 2. A powder or fiber having on its surface a coating formed from the alkoxysilane compound according to claim 1. 3. A solid alkylating agent comprising the powder or fiber according to claim 2.