JPH0525186A - Production of polymerizable monomer - Google Patents

Abstract

PURPOSE:To simplify the reaction process, avoid disadvantages in production processes and simultaneously improve yield and purity of a polymerizable monomer composed of a silyl esterified substance of a maleic acid monoester in a method for producing the aforementioned polymerizable monomer. CONSTITUTION:A monohydric alcohol, a triorganosilanol and a Lewis acid or a Lewis base are added to maleic anhydride to carry out esterifying reaction accompanied by dehydrating reaction. Thereby, the objective polymerizable monomer composed of a silyl esterified substance of a maleic acid monoester is produced.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for producing a polymerizable monomer composed of a silyl ester of maleic acid monoester.

[0002]

2. Description of the Related Art Conventionally, a polymerizable monomer obtained by silyl esterifying a carboxyl group of maleic acid monoester to introduce a silyl group into the molecule is disclosed in, for example, JP-A-63 / 1988.
As disclosed in JP-A-215780, it is generally produced by a method of dehydrochlorinating maleic acid monoester and triorganochlorosilane in the presence of a base such as triethylamine.

[0003]

However, in the method using dehydrochlorination using a base such as triethylamine,
Generally, first, an amine salt of maleic acid monoester is formed as an intermediate, and then it is reacted with triorganochlorosilane, so that the reaction process has multiple stages,
Further, since a crystalline hydrochloride such as triethylamine hydrochloride is produced as a by-product, a step of removing this hydrochloride is required, which is disadvantageous in the manufacturing process. There is also a problem that the yield and purity of the target silyl esterified product of maleic acid monoester are low.

In view of the above-mentioned conventional problems, the present invention simplifies the reaction step and avoids the disadvantages in the production process in the method for producing a polymerizable monomer comprising a silyl esterified product of maleic acid monoester. The purpose of the present invention is to improve the yield and purity of the polymerizable monomer.

[0005]

Means for Solving the Problems The inventors of the present invention have conducted extensive studies in order to achieve the above-mentioned object. As a result, the silyl esterification of maleic acid monoester was confirmed to be carried out by using a specific catalyst. Radicals and triorganosilano
The present invention has been completed based on the finding that this can be achieved by a dehydration reaction with silane, which can greatly improve the yield and purity of the target silyl esterified product as well as simplifying the reaction process.

That is, the present invention relates to maleic anhydride.
A monovalent alcohol, triorganosilanol and Lewis acid or Lewis base are added to carry out an esterification reaction accompanied by a dehydration reaction to produce a polymerizable monomer composed of a silyl esterified product of maleic acid monoester. The present invention relates to a method for producing a polymerizable monomer characterized by:

[0007]

The monovalent alcohol used in the present invention includes linear, branched or cyclic alkyl alcohols having usually 1 to 12 carbon atoms.
The seeds may be used alone or in combination of two or more.

In the triorganosilanol used in the present invention, the three organic groups may be the same or different from each other. The organic group usually has 1 to 2 carbon atoms.
One linear, branched or cyclic alkyl group may be mentioned, and it may be an aryl group or a substituted aryl group.

Examples of the above alkyl group include methyl, ethyl, n-propyl, n-butyl, n-octyl, isopropyl, isobutyl, s-butyl, t-butyl, 2-ethylhexyl, cyclopropyl and cyclohexyl. And the substituted aryl group is halogen,
There is an aryl group substituted with an alkyl group, an acyl group, a nitro group or an amino group having up to about 10 carbon atoms.

Examples of the Lewis acid or Lewis base used in the present invention include organic tin compounds such as dibutyltin dilaurate, dibutyltin diacetate and dibutyltin dioctoate, titanium tetrachloride, tetrabutoxytitanium and titanocene dichloride. And Lewis acids such as titanium compounds, and Lewis bases such as triethylamine and imidazole.

In the present invention, the above-mentioned monovalent alcohol, triorganosilanol and Lewis acid or Lewis base are added to maleic anhydride to carry out an esterification reaction accompanied by a dehydration reaction. Needless to say, the chemical reaction includes both a monoesterification reaction of maleic anhydride and a monovalent alcohol and a silyl esterification reaction of triorganosilanol.

Both of these reactions may be carried out first or simultaneously, and therefore the order of addition of the monovalent alcohol and the triorganosilanol to maleic anhydride is not particularly limited. However, it is usually usual to add the monovalent alcohol first, followed by the triorganosilanol.

In adding the above monovalent alcohol,
Maleic anhydride may be in a solid (crystal) state, may be in a molten state by heating, or may be in a solution state in which it is dissolved in a solvent. The latter two are preferable in terms of reaction uniformity. Even if the solid remains, there is no particular problem in the reaction.

The monoesterification reaction between maleic anhydride and monovalent alcohol proceeds even at room temperature, but it is also effective to heat it because it is an endothermic reaction. The monohydric alcohol is usually used in a proportion of 1 to 3 mol per 1 equivalent of the carboxyl group of maleic anhydride.

The dehydration reaction in which triorganosilanol is added and carried out in the presence of a Lewis acid or a Lewis base can be carried out usually at a temperature of -70 to 300 ° C, preferably -30 to 250 ° C. Triorganosilanol
Usually, it is 1 per 1 equivalent of the carboxyl group of maleic anhydride.
It is preferable to set it to ˜5 mol.

In both of the above reactions, a dehydrating agent may be used to remove the water produced during the reaction. Examples of such a dehydrating agent include anhydrous inorganic salts such as anhydrous magnesium sulfate, anhydrous sodium sulfate and anhydrous calcium chloride, carbodiimides such as N.N'-dicyclohexylcarbodiimide, silica gel and molecular sieves. ..

In both of the above reactions, as a solvent for dissolving maleic anhydride or used for the solution reaction, an aromatic hydrocarbon solvent such as benzene, toluene, xylene, ethyl acetate, butyl acetate, etc. There are ester-based solvents, diethyl ether, tetrahydrofuran and other ether-based solvents, and hexane and other aliphatic hydrocarbon-based solvents, etc., which can be selected appropriately according to the type of monovalent alcohol or triorganosilanol. do it.

The reaction product thus obtained is mainly composed of a silyl ester of maleic acid monoester, and it goes without saying that the conventional amine hydrochloride crystals and the like are contained therein. Not included at all.
Therefore, the solvent is distilled off from the solution of this reaction product, and then the solvent is distilled off under reduced pressure to obtain a target polymerizable monomer comprising a silyl esterified product of maleic acid monoester in an amount of generally 75% by weight or more. Can be obtained in a high yield of 80% by weight or more and usually in a high purity of 90% by weight or more, preferably 95% by weight or more.

The silyl esterified product can be easily confirmed by an infrared absorption spectrum (IR) or a nuclear magnetic resonance spectrum (NMR). The purity of the silyl ester compound is determined by gas chromatography.
Can be measured at.

The silyl esterified product of maleic acid monoester obtained by the method of the present invention can be used as a polymerizable monomer by any known polymerization method such as radical polymerization method.
As a polymer, it has a silyl group in its side chain and can be widely used in various applications such as hydrolyzable plastics, underwater antifouling coatings, and polymeric materials for medical use. it can.

[0021]

As described above, the polymerizable monomer of the present invention is used.
Unlike the conventional method of dehydrochlorination in the presence of a base, the production method of does not pass through intermediates such as amine salts, thus reducing multi-step reactions and simplifying the reaction process. It is also possible to eliminate the step of separating and removing solid by-products such as triethylamine hydrochloride.
Further, as compared with the above-mentioned conventional method, remarkable effects such as a great improvement in yield and purity of the polymerizable monomer composed of the obtained silyl ester of maleic acid monoester can be obtained.

[0022]

EXAMPLES The present invention will be specifically described below with reference to examples.

Example 1 1 liter of butyl acetate was placed in a 5-liter four-necked flask equipped with a stirrer and a heating / cooling device, and 1 mol of maleic anhydride was added to the flask and dissolved at room temperature.
Further, 1 mol of methyl alcohol was added. Then, stirring was continued and 10 mmol of triethylamine was added.
Next, 1.5 mol of t-hexyldimethylsilanol was added dropwise over 40 minutes. After the dropwise addition was completed, the reaction solution was heated to 80 ° C., and stirring was continued for another 2 hours. The produced water was refluxed and removed, and then the reaction was terminated.

From the solution of the reaction product thus obtained, butyl acetate was distilled off with a rotary evaporator, and the solution was subjected to vacuum distillation. 141 at a pressure of 2.0 mmHg
A main distillate of ˜143 ° C. was taken out. The yield of the obtained polymerizable monomer was 79.8% by weight, and the purity was 97.9% by weight.
It was.

The purity is measured by gas chromatography, and the measurement conditions are as follows. Model: HP 5890 SERIES II Column: G-100 (manufactured by Chemicals Inspection Association) Column temperature: 230 ° C (fixed) Injection / Digiexion temperature: 250 ° C Flow rate: 19.8 ml / min Retention time: 30 minutes

The fact that the polymerizable monomer obtained in Example 1 above was a silyl ester of maleic acid monoester was confirmed by investigating the following characteristic absorption by IR. -C (= O)-; 1700 to 1750 cm ^-1 -Si-C-; 1400 to 1480 cm ^-1 -Si-O-; 1120 to 1180 cm ^-1 1200 to 1260 cm ^-1 1370 to 1410 cm ^-1

Further, it was confirmed by NMR that the ¹ H-NMR characteristic absorption: δ (ppm) was the above silyl ester compound. Table 1 shows the above characteristic absorption. The measurement conditions of NMR include CDCl ₃
In solution, it is an internal standard CHCl ₃ (δ = 7.27).

[0028]

[Table 1]

For reference, FIG. 1 shows the IR spectrum of the polymerizable monomer obtained in Example 1, and FIG. 2 shows the NMR spectrum of the polymerizable monomer.

Example 2 2 liters of tetrahydrofuran was placed in a 5 liter four-necked flask equipped with a stirrer and a heating / cooling device, and 1 mol of maleic anhydride was added thereto and dissolved at room temperature. 1 mol of methyl alcohol was added. Then, the mixture was continuously stirred and 7 mmol of dibutyltin diacetate was added. Next, 1.1 mol of t-butyldimethylsilanol was added dropwise over 20 minutes. After the dropwise addition was completed, the reaction solution was heated to 80 ° C., and stirring was continued for another 2 hours. The produced water was refluxed and removed, and then the reaction was terminated.

Tetrahydrofuran was distilled off from the solution of the reaction product thus obtained by a rotary evaporator, and then the solution was subjected to vacuum distillation. At a pressure of 1.0 mmHg, 68 to 70 ° C. was taken out as the main distillate. The yield of the obtained polymerizable monomer was 91.1% by weight, and the purity was 98.1% by weight.

The fact that the polymerizable monomer was a silyl ester of maleic acid monoester was confirmed and identified by IR and NMR as in the case of Example 1. Table 2 shows the NMR of this polymerizable monomer.
Shows the characteristic absorption of.

[0033]

[Table 2]

Example 3 2 liters of benzene were placed in a 5-liter four-necked flask equipped with a stirrer and a heating / cooling device, and 1 mol of maleic anhydride was added to the flask and dissolved at room temperature. 1 mol of alcohol was added. Then, the mixture was continuously stirred and 12 mmol of imidazole was added. Next, 1.1 mol of triisopropylsilanol was added dropwise over 40 minutes. After the completion of dropping, the reaction solution is heated to 80 ° C. and further 2
Stirring was continued for hours. The produced water was refluxed and removed, and then the reaction was terminated.

From the solution of the reaction product thus obtained, benzene was distilled off with a rotary evaporator, and then the solution was subjected to vacuum distillation. 85-8 at a pressure of 1.5 mmHg
The main distillate was taken out at 7 ° C. Obtained polymerizable monomer
The yield was 81.4% by weight and the purity was 98.8% by weight.

The fact that the polymerizable monomer was a silyl ester of maleic acid monoester was confirmed and identified by IR and NMR as in the case of Example 1. Table 3 shows the NMR of this polymerizable monomer.
Shows the characteristic absorption of.

[0037]

[Table 3]

Example 4 2 liters of toluene was placed in a 5 liters four-necked flask equipped with a stirrer and a heating / cooling device, and 1 mol of maleic anhydride was added to and dissolved in the mixture at room temperature. 1 mol of isoamyl alcohol was added. Then, while stirring at room temperature, dibutyltin dilaurate 0.01
Mole was added. Next, triisopropylsilanol 1
Molar was added dropwise over 30 minutes. After dropping, add 5
Heat to 0 ° C. and continue stirring for an additional 2 hours. The produced water was refluxed and removed, and then the reaction was terminated.

From the solution of the reaction product thus obtained, toluene was distilled off with a rotary evaporator, and then the solution was subjected to vacuum distillation. 155 at a pressure of 1.5 mmHg
The main distillate was taken out at 157 ° C. The yield of the obtained polymerizable monomer was 83.3% by weight, and the purity was 98.7% by weight.

The fact that the polymerizable monomer was a silyl ester of maleic acid monoester was confirmed and identified by IR and NMR as in the case of Example 1. Table 4 shows the NMR of this polymerizable monomer.
Shows the characteristic absorption of.

[0041]

[Table 4]

Example 5 To a 5 liter 4-necked flask equipped with a stirrer and a heating / cooling device, 1 mol of maleic anhydride and 1 mol of methyl alcohol were added, and the mixture was stirred at room temperature for 1 hour. Continued. After cooling to 5 ° C., 5 mmol of titanium tetrachloride and 0.5 mol of anhydrous magnesium sulfate were added with continuous stirring. Next, 1 mol of t-butyldiphenylsilanol was added dropwise over 30 minutes. After completion of dropping, toluene 1.5
A reactor was added, the reaction solution was heated to 30 ° C., stirring was continued for 2 hours, and then the reaction was completed. The water produced during the reaction was trapped with anhydrous magnesium sulfate.

From the solution of the reaction product thus obtained, toluene was distilled off with a rotary evaporator, and then the solution was subjected to vacuum distillation. 141-at a pressure of 1.0 mmHg
The main distillate was taken out at 144 ° C. The yield of the obtained polymerizable monomer was 83.1% by weight, and the purity was 97.4% by weight.

The fact that the polymerizable monomer was a silyl ester of maleic acid monoester was confirmed and identified by IR and NMR as in the case of Example 1. Table 5 shows the NMR of this polymerizable monomer.
Shows the characteristic absorption of.

[0045]

[Table 5]

Example 6 1 mol of maleic anhydride was added to a 5 liter 4-necked flask equipped with a stirrer and a heating / cooling device, and the mixture was heated to 80 ° C. to be melted and then n-amyl alcohol. 1
Mol was added and the mixture was kept at 80 ° C. for 30 minutes. Then, the mixture was continuously stirred, and 10 mmol of dibutyltin diacetate and 0.5 mol of anhydrous magnesium sulfate were added. After adding 2 liters of toluene, triisopropylsilanol 1.
1 mol was added dropwise over 40 minutes. After the dropwise addition was completed, the reaction solution was heated to 50 ° C., and stirring was continued for 2 hours. The produced water was refluxed and removed, and then the reaction was terminated.

From the solution of the reaction product thus obtained, toluene was distilled off with a rotary evaporator, and then the solution was subjected to vacuum distillation. 141-at a pressure of 2.0 mmHg
The main distillate was taken out at 143 ° C. The yield of the obtained polymerizable monomer was 85.0% by weight, and the purity was 96.8% by weight.

The fact that the polymerizable monomer was a silyl ester of maleic acid monoester was confirmed and identified by IR and NMR as in the case of Example 1. Table 6 shows the NMR of this polymerizable monomer.
Shows the characteristic absorption of.

[0049]

[Table 6]

Comparative Example 1 1 liter of toluene was placed in a 4-necked 5-liter four-necked flask equipped with a stirrer and a heating / cooling device, and 1 mol of maleic anhydride was added to and dissolved in the mixture. -1 mol of ru was added. After that, the reaction solution is 5 ° C.
Then, with stirring, 1 mol of triethylamine was added dropwise over 1 hour. The dropping part turned yellow, but became colorless and transparent by stirring. The reaction temperature was maintained at 20 ° C.

Next, while maintaining the transparent liquid at 10 ° C. and continuously stirring, 1 mol of t-butyldimethylchlorosilane was added dropwise over 15 minutes. Immediately after the dropping, precipitation of hydrochloride of triethylamine was observed. After completion of the dropping, stirring was continued for another 2 hours at room temperature.

The solution of the reaction product thus obtained is
Suction filtration was performed using a glass filter to remove the triethylamine hydrochloride. The filtration residue was washed with 0.5 liter of toluene, and this washing solvent was added to the filtrate. Then, toluene was distilled off from the filtrate with a rotary evaporator, and the residue was subjected to vacuum distillation. 11 at a pressure of 8.0 mmHg
The main distillate was taken out at 2 to 115 ° C. Some white needle-like crystals were found in the distillate. The yield of the obtained polymerizable monomer was 71.5% by weight, and the purity was 82.2% by weight.

The fact that the polymerizable monomer was a silyl ester of maleic acid monoester was confirmed and identified by IR and NMR as in the case of Example 1. The IR characteristic absorption and the NMR characteristic absorption were almost the same as the results of Example 2 described above.

As is clear from the above results, Example 1
In Nos. 6 to 6, the reaction process was simplified, no by-products were generated during the reaction, and the yield and purity of the target polymerizable monomer were good.

On the other hand, in Comparative Example 1, a step of producing an intermediate consisting of an amine salt of maleic acid monoester is required, and generation of a hydrochloride of triethylamine as a by-product is observed during the reaction. However, there was a disadvantage in the manufacturing process such as the step of removing this after the reaction was necessary. In addition, the yield and purity of the target polymerizable monomer were low.

[Brief description of drawings]

FIG. 1 is a characteristic diagram showing an infrared absorption spectrum of a polymerizable monomer obtained in Example 1.

2 is a characteristic diagram showing a nuclear magnetic resonance spectrum of the polymerizable monomer obtained in Example 1. FIG.

Claims (1)

Claims: 1. Maleic anhydride is added with monovalent alcohol, triorganosilanol and Lewis acid or Lewis base to carry out an esterification reaction accompanied by a dehydration reaction to give maleic acid. A method for producing a polymerizable monomer, which comprises producing a polymerizable monomer comprising a monoester silyl ester compound.