JP7147689B2 - Method for producing imino group-containing organooxysilane compound - Google Patents

Description

TECHNICAL FIELD The present invention relates to a method for producing an imino group-containing organooxysilane compound.

Nitrogen-containing organooxysilane compounds are useful as paint additives, adhesives, silane coupling agents, fiber treatment agents, surface treatment agents, and the like.
In particular, the imino group-containing organooxysilane compound has a structure in which the amino group is protected. It is useful as a curable composition having the effect of (adhesiveness, reinforcing property improvement). That is, a composition containing an imino group-containing organooxysilane compound does not exhibit reactivity in a moisture-blocked system and is stable. The group is regenerated and shows the same effect as when an amino-based silane coupling agent is added.

Examples of the method for producing an imino group-containing organooxysilane compound include a method of reacting 3-aminopropyltrimethoxysilane and cinnamaldehyde with an organic solvent while azeotropic dehydration (see Patent Document 1), and methyl isobutyl ketone. under reflux of, 3-aminopropyltrimethoxysilane is added dropwise for reaction while azeotropic dehydration (see Patent Document 2), and benzaldehyde and 3-aminopropyltrimethoxysilane are azeotropically dehydrated under reflux of toluene. A reaction method (see Patent Document 3) and the like have been proposed.
As described above, water produced as a by-product of the reaction between the carbonyl group-containing compound and the aminoorganoxysilane compound is generally azeotropically dehydrated during the reaction to rapidly distill the water out of the reactor. Widely used.

U.S. Pat. No. 2,942,019 JP-A-7-247294 JP 2017-66335 A

In the methods described in Patent Documents 1 to 3 above, the reason why the water produced as a reaction by-product is quickly distilled off from the reactor by azeotropic dehydration during the reaction is that (1) the equilibrium of the reaction is This is to allow the reaction to proceed in a state inclined toward the imino group-forming reaction side, and (2) to prevent the by-produced water from causing a hydrolytic condensation reaction of the formed imino group-containing organooxysilane.
However, especially when the organooxy group bonded to the silicon atom is a non-bulky group such as a methoxy group or an ethoxy group, the temperature during azeotropic dehydration is high, and as a result, water is distilled rather than distilled. In some cases, the target imino group-containing organosilane compound is first subjected to the hydrolytic condensation reaction, resulting in a decrease in the yield of the target product, which is not industrially advantageous.

SUMMARY OF THE INVENTION An object of the present invention is to provide a method for producing an imino group-containing organooxysilane compound efficiently and in good yield.

As a result of intensive studies to achieve the above object, the present inventors have found that the imino group-generating reaction is particularly rapid and the equilibrium is biased toward the imino group-generating reaction, that is, an aldehyde compound is used as a raw material containing a carbonyl group. In the system used, rather than removing water produced as a reaction by-product during the reaction from the reaction system by azeotropic dehydration, it is better to remove water after the reaction without a large decrease in yield. The inventors have found that an imino group-containing organooxysilane compound can be obtained, and completed the present invention.

（式中、Ｒ¹は、水素原子またはヘテロ原子を含んでいてもよい炭素数１～２０のｍ価炭化水素基を表し、Ｒ²は、水素原子または炭素数１～２０の１価炭化水素基を表し、ｍは、１～１０の整数を表す。）
で示されるカルボニル基含有化合物と、
下記一般式（２）

（式中、Ｒ³は、炭素数１～２０の２価炭化水素基を表し、Ｒ⁴およびＲ⁵は、それぞれ独立して炭素数１～２０の１価炭化水素基を表し、ｎは、０、１または２を表す。）
で示されるアミノオルガノキシシラン化合物を反応させる、下記一般式（３）

（式中、Ｒ¹～Ｒ⁵、ｍおよびｎは、前記と同じ意味を表す。）
で示されるイミノ基含有オルガノキシシラン化合物の製造方法であって、
副生物として生じた水を反応系外へ除去することなく前記反応を行い、前記反応の終了後に前記水を除去する工程を有することを特徴とするイミノ基含有オルガノキシシラン化合物の製造方法、
２． 前記水を除去する工程が、反応液の分液操作で二層分離した水層を除去することにより行われる１のイミノ基含有オルガノキシシラン化合物の製造方法、
３． 前記Ｒ²が、水素原子である１または２のイミノ基含有オルガノキシシラン化合物の製造方法
を提供する。 That is, the present invention
1. General formula (1) below

(In the formula, R ¹ represents a hydrogen atom or an m-valent hydrocarbon group having 1 to 20 carbon atoms which may contain a heteroatom; R ² represents a hydrogen atom or a monovalent hydrocarbon group having 1 to 20 carbon atoms; group, and m represents an integer of 1 to 10.)
A carbonyl group-containing compound represented by
General formula (2) below

(wherein R ³ represents a divalent hydrocarbon group having 1 to 20 carbon atoms, R ⁴ and R ⁵ each independently represent a monovalent hydrocarbon group having 1 to 20 carbon atoms, and n is represents 0, 1 or 2.)
The following general formula (3) is reacted with an aminoorganoxysilane compound represented by

(In the formula, R ¹ to R ⁵ , m and n have the same meanings as above.)
A method for producing an imino group-containing organooxysilane compound represented by
A method for producing an imino group-containing organooxysilane compound, characterized in that the reaction is carried out without removing water produced as a by-product out of the reaction system, and the water is removed after completion of the reaction,
2. 1. Method for producing an imino group-containing organooxysilane compound, wherein the step of removing water is performed by removing a water layer separated into two layers by a liquid separation operation of the reaction solution;
3. Provided is a method for producing an organooxysilane compound containing one or two imino groups, wherein R ² is a hydrogen atom.

INDUSTRIAL APPLICABILITY According to the present invention, nitrogen-containing organosilane compounds useful as paint additives, adhesives, silane coupling agents, fiber treatment agents, surface treatment agents, etc. can be produced efficiently and in good yield.

The present invention will be specifically described below.
A method for producing an imino group-containing organosilane compound represented by the following general formula (3) of the present invention comprises a carbonyl group-containing compound represented by the following general formula (1) and an aminoorgano compound represented by the following general formula (2). The xysilane compound is reacted without removing water produced as a by-product during the reaction to the outside of the reaction system, and the water produced as a by-product is removed after the completion of the reaction.

In general formulas (1) and (3), R ¹ represents a hydrogen atom or an m-valent hydrocarbon group having 1 to 20 carbon atoms which may contain a heteroatom, and R ² is a hydrogen atom or a C 1 represents a monovalent hydrocarbon group of ∼20, and m represents an integer of 1-10;
In general formulas (2) and (3), R ³ represents a divalent hydrocarbon group having 1 to 20 carbon atoms, and R ⁴ and R ⁵ each independently represent a monovalent hydrocarbon group having 1 to 20 carbon atoms. represents a hydrocarbon group, and n represents 0, 1 or 2;

The m-valent hydrocarbon group of R ¹ having 1 to 20 carbon atoms, preferably 1 to 10 carbon atoms, which may contain a heteroatom, may be linear, branched or cyclic. Examples include linear groups such as methyl, ethyl, n-propyl, n-butyl, n-pentyl, n-hexyl, n-heptyl, n-octyl, n-decyl, dodecyl, tetradecyl, hexadecyl, octadecyl, and icosyl groups. branched alkyl groups such as isopropyl, isobutyl, sec-butyl, tert-butyl, thexyl and 2-ethylhexyl groups; cyclic alkyl groups such as cyclopentyl and cyclohexyl groups; vinyl, allyl (2-propenyl), 1 - alkenyl groups such as propenyl group; aryl groups such as phenyl and tolyl groups; aralkyl groups such as benzyl group; heteroatom-containing aryl groups such as pyridyl and pyrazyl groups; alkylene groups such as methyltrimethylene, 2-methyltrimethylene (isobutylene), tetramethylene, hexamethylene, octamethylene and decamethylene groups; arylene groups such as phenylene groups; aralkylene groups such as methylenephenylene and methylenephenylenemethylene groups; Examples thereof include heteroatom-containing alkylene groups such as oxamethylene and 1-azamethylene groups.

Among these, from the viewpoint of availability of raw materials and usefulness of products, R ¹ is an alkyl group having 1 to 3 carbon atoms such as methyl group, ethyl group, n-propyl group; phenyl group, tolyl group; An aryl group having 6 to 7 carbon atoms such as a phenylene group is preferred.

The monovalent hydrocarbon group having 1 to 20 carbon atoms, preferably 1 to 10 carbon atoms, and more preferably 1 to 5 carbon atoms for R ² , R ⁴ and R ⁵ may be linear, branched or cyclic. Any of them may be used, and specific examples include methyl, ethyl, n-propyl, n-butyl, n-pentyl, n-hexyl, n-heptyl, n-octyl, n-decyl, dodecyl, tetradecyl, hexadecyl, octadecyl, Linear alkyl groups such as icosyl group; branched alkyl groups such as isopropyl, isobutyl, sec-butyl, tert-butyl, thexyl and 2-ethylhexyl groups; cyclic alkyl groups such as cyclopentyl and cyclohexyl groups; vinyl, allyl, Examples include alkenyl groups such as butenyl and pentenyl groups; aryl groups such as phenyl and tolyl groups; and aralkyl groups such as benzyl groups.

Among these, from the viewpoint of availability of raw materials and usefulness of products, R ² is an alkyl group having 1 to 3 carbon atoms such as methyl group, ethyl group and n-propyl group; allyl group and butenyl group; , pentenyl group and other alkenyl groups having 2 to 5 carbon atoms are preferred, and hydrogen atoms are more preferred. R ⁴ and R ⁵ are preferably C 1 to 3 alkyl groups such as methyl, ethyl and propyl groups.

The divalent hydrocarbon group of R ³ having 1 to 20 carbon atoms, preferably 1 to 10 carbon atoms, more preferably 1 to 5 carbon atoms, may be linear, branched or cyclic. Examples include alkylene groups such as methylene, ethylene, methylethylene (propylene), trimethylene, 1-methyltrimethylene, 2-methyltrimethylene (isobutylene), tetramethylene, hexamethylene, octamethylene, and decamethylene groups; phenylene groups, etc. and aralkylene groups such as ethylenephenylene and ethylenephenylenemethylene groups.

Among these, from the viewpoint of the availability of raw materials and the usefulness of the product, R ³ is an alkylene group having 1 to 3 carbon atoms such as a methylene group, an ethylene group, a methylethylene (propylene) group, and a trimethylene group; A phenylene group is preferred.

m in the general formula (1) represents an integer of 1 to 10, preferably an integer of 1 to 5, and n in the general formula (2) is 0, 1 or 2, but 0 or 1 is preferred.

Specific examples of the carbonyl group-containing compound represented by the general formula (1) include aliphatic aldehyde compounds such as formaldehyde, acetaldehyde, propionaldehyde, butyraldehyde, and cyclohexanecarbaldehyde; aromatic aldehyde compounds such as benzaldehyde and tolualdehyde; cinnamaldehyde compounds such as maldehyde, α-methylcinnamaldehyde, α-pentylcinnamaldehyde; pyridyl group-containing aldehyde compounds such as pyridinecarbaldehyde; malondialdehyde, succinaldehyde, o-phthalaldehyde, isophthalaldehyde, terephthalaldehyde, etc. Dialdehyde compounds; trialdehyde compounds such as 1,2,4-benzenetricarbaldehyde and 1,3,5-benzenetricarbaldehyde; aliphatic ketone compounds such as acetone, methyl ethyl ketone, methyl isobutyl ketone and acetylacetone; acetophenone, benzophenone and aromatic ketone compounds such as diacetylbenzene.

Specific examples of the aminoorganoxysilane compound represented by the general formula (2) include aminomethyltrimethoxysilane, aminomethyldimethoxymethylsilane, aminomethylmethoxydimethylsilane, aminomethyltriethoxysilane, aminomethyldiethoxymethylsilane, Aminomethylorganoxysilane compounds such as aminomethylethoxydimethylsilane; 3-aminopropyltrimethoxysilane, 3-aminopropyldimethoxymethylsilane, 3-aminopropylmethoxydimethylsilane, 3-aminopropyltriethoxysilane, 3-aminopropyl Examples include aminopropylorganoxysilane compounds such as diethoxymethylsilane and 3-aminopropylethoxydimethylsilane.

Specific examples of the imino group-containing organooxysilane compound represented by the general formula (3) obtained by the above reaction include methyleneaminomethyltrimethoxysilane, methyleneaminomethyldimethoxymethylsilane, methyleneaminomethylmethoxydimethylsilane, methyleneaminomethyl triethoxysilane, methyleneaminomethyldiethoxymethylsilane, methyleneaminomethylethoxydimethylsilane, 3-(methyleneamino)propyltrimethoxysilane, 3-(methyleneamino)propyldimethoxymethylsilane, 3-(methyleneamino)propylmethoxydimethylsilane silane, 3-(methyleneamino)propyltriethoxysilane, 3-(methyleneamino)propyldiethoxymethylsilane, 3-(methyleneamino)propylethoxydimethylsilane and other methyleneamino group-containing organooxysilane compounds; methoxysilane, benzylideneaminomethyldimethoxymethylsilane, benzylideneaminomethylmethoxydimethylsilane, benzylideneaminomethyltriethoxysilane, benzylideneaminomethyldiethoxymethylsilane, benzylideneaminomethylethoxydimethylsilane, 3-(benzylideneamino)propyltrimethoxysilane, 3-(benzylideneamino)propyldimethoxymethylsilane, 3-(benzylideneamino)propylmethoxydimethylsilane, 3-(benzylideneamino)propyltriethoxysilane, 3-(benzylideneamino)propyldiethoxymethylsilane, 3-(benzylideneamino) ) benzylideneamino group-containing organooxysilane compounds such as propylethoxydimethylsilane; pyridylmethyleneaminomethyltrimethoxysilane, pyridylmethyleneaminomethyldimethoxymethylsilane, pyridylmethyleneaminomethylmethoxydimethylsilane, pyridylmethyleneaminomethyltriethoxysilane, pyridylmethylene aminomethyldiethoxymethylsilane, pyridylmethyleneaminomethylethoxydimethylsilane, 3-(pyridylmethyleneamino)propyltrimethoxysilane, 3-(pyridylmethyleneamino)propyldimethoxymethylsilane, 3-(pyridylmethyleneamino)propylmethoxydimethylsilane , 3-(pyridylmethyleneamino)propyltriethoxysilane, 3-(pyridylmethyleneamino)propyldiethoxymethylsilane, 3- Pyridylmethyleneamino group-containing organooxysilane compounds such as (pyridylmethyleneamino) propylethoxydimethylsilane; N,N-bis(trimethoxysilylmethyl)-1,4-xylene-α,α'-diimine, N,N- Bis(dimethoxymethylsilylmethyl)-1,4-xylene-α,α'-diimine, N,N-bis(methoxydimethylsilylmethyl)-1,4-xylene-α,α'-diimine, N,N- Bis(triethoxysilylmethyl)-1,4-xylene-α,α'-diimine, N,N-bis(diethoxymethylsilylmethyl)-1,4-xylene-α,α'-diimine, N,N Bisorganoxysilyl group-containing 1,4-xylene-α,α'-diimine compounds such as -bis(methoxydimethylsilylmethyl)-1,4-xylene-α,α'-diimine.

In the production method of the present invention, the amount of the aminoorganoxysilane compound represented by the general formula (2) is not particularly limited, but from the viewpoint of reactivity and productivity, the carbonyl group-containing compound represented by the general formula (1) It is preferably 0.5 to 2.0 mol, more preferably 0.8 to 1.5 mol, per 1 mol of the carbonyl group of the compound.

A solvent may be added during the above reaction as long as the object of the present invention is not impaired.
Specific examples of solvents include hydrocarbon solvents such as pentane, hexane, cyclohexane, heptane, isooctane, benzene, toluene and xylene; ether solvents such as diethyl ether, tetrahydrofuran and dioxane; ester solvents such as ethyl acetate and butyl acetate. Solvents; aprotic polar solvents such as acetonitrile and N,N-dimethylformamide; chlorinated hydrocarbon solvents such as dichloromethane and chloroform; alcoholic solvents such as methanol and ethanol; Hydrocarbon solvents, ether solvents and ester solvents are preferable, and hydrocarbon solvents are more preferable, from the viewpoint of suppressing the hydrolytic condensation reaction of the contained organosilane compound with water. These solvents may be used singly or in combination of two or more.

Although the reaction temperature for the above reaction is not particularly limited, it is preferably 0 to 200°C, more preferably 0 to 100°C, and even more preferably 0 to 80°C from the viewpoint of improving the yield.

As a method for producing the imino group-containing organosilane compound represented by the general formula (3), when a solvent is used, a carbonyl group-containing compound and a solvent are charged, and an aminoorganoxysilane compound is added dropwise. A batch reaction method, such as a method in which a silane compound and a solvent are charged and a carbonyl group-containing compound is added dropwise, or a method in which a carbonyl group-containing compound and an aminoorganoxysilane compound are added dropwise to a solvent at the same time; carbonyl group-containing compound, aminoorganoxysilane. A continuous reaction method, such as a method of continuously feeding a compound and a solvent into a reactor or a reaction tube and continuously withdrawing a product, can be used.
When a solvent is not used, a batch reaction method such as a method of charging a carbonyl group-containing compound and dropping an aminoorganoxysilane compound, a method of charging an aminoorganoxysilane compound and dropping a carbonyl group-containing compound; A continuous reaction method, such as a method of continuously feeding the contained compound and the aminoorganoxysilane compound into a reactor or a reaction tube and continuously withdrawing the product, can be used.

In addition, although water is produced as a by-product in this reaction, as described above, in the present invention, the reaction is carried out without removing the water produced as a reaction by-product out of the reaction system, and water is removed after the reaction. is characterized by
Azeotropic dehydration is carried out in order to remove the generated water out of the reaction system during the reaction. In this case, the solvent must be refluxed, so the reaction temperature must be high. Since the hydrolytic condensation reaction most easily occurs at the stage when water is produced, if the reaction temperature is high at the time when water is produced, the hydrolytic condensation reaction will proceed remarkably. Therefore, it is advantageous to carry out the reaction under mild conditions during the reaction, that is, at the stage where water is being produced, and to remove the water after the reaction.

The method for removing water after the reaction is not particularly limited, and includes a method of azeotropic dehydration under normal pressure or reduced pressure, a method of removing the water layer separated into two layers by a liquid separation operation, and a method of adding a dehydrating agent. However, from the viewpoint of ease of implementation and yield, a method of removing the aqueous layer separated into two layers by a liquid separation operation is preferable.
As a method for removing the water layer separated into two layers by the liquid separation operation, in the case of batch reaction, stop the stirrer after the reaction, and if the water layer settles, extract the water layer from the bottom of the reactor and remove it. When the water layer floats, the organic layer is first drawn out from the bottom of the reactor, and then the water layer is drawn out from the bottom of the reactor and discarded. In the case of continuous reaction, a method of supplying the product to a decanter and extracting the water layer separated into two layers in the decanter can be used.
The target product can be recovered from the organic layer obtained as described above by an ordinary method such as distillation.

EXAMPLES The present invention will be described in more detail below with reference to examples and comparative examples, but the present invention is not limited to the following examples.

[Example 1]
509.3 g (4.8 mol) of benzaldehyde and 1,200 ml of toluene were placed in a flask equipped with a stirrer, reflux vessel, dropping funnel and thermometer, and 717.2 g of 3-aminopropyltrimethoxysilane was added at 20-40°C. (4.0 mol) was added dropwise over 2 hours and stirred at that temperature for 1 hour. The reaction solution was transferred to a separatory funnel and the lower aqueous layer separated into two layers was removed. The upper layer was distilled to obtain 768.8 g of 3-(benzylideneamino)propyltrimethoxysilane as a fraction having a boiling point of 149° C./0.4 kPa. Yield was 72%.

[Comparative Example 1]
A flask equipped with a stirrer, Dean-Stark apparatus, reflux, dropping funnel and thermometer was charged with 509.3 g (4.8 mol) of benzaldehyde and 1,200 ml of toluene and heated until the toluene was refluxed. 717.2 g (4.0 mol) of 3-aminopropyltrimethoxysilane was added dropwise over 2 hours while distilling off the water produced under reflux of toluene (internal temperature 116° C.), and further under reflux for 1 hour. Stirred. The obtained reaction liquid was distilled to obtain 540.9 g of 3-(benzylideneamino)propyltrimethoxysilane as a fraction having a boiling point of 149° C./0.4 kPa. Yield was 51%.

[Example 2]
Reaction and separation were carried out in the same manner as in Example 1, except that 717.2 g (4.0 mol) of 3-aminopropyltriethoxysilane was changed to 885.6 g (4.0 mol) of 3-aminopropyltriethoxysilane. The liquid was separated and the upper layer was distilled to obtain 1,195.5 g of 3-(benzylideneamino)propyltriethoxysilane as a fraction having a boiling point of 164° C./0.4 kPa. Yield was 97%.

[Example 3]
A flask equipped with a stirrer, reflux, dropping funnel and thermometer was charged with 509.3 g (4.8 mol) of benzaldehyde and 1,200 ml of toluene and heated to 70°C. After the internal temperature stabilized, 885.6 g (4.0 mol) of 3-aminopropyltriethoxysilane was added dropwise at 70 to 80° C. over 2 hours, and the mixture was stirred at that temperature for 1 hour. After cooling to 25° C., the reaction solution was transferred to a separatory funnel and the lower aqueous layer separated into two layers was removed. The upper layer was distilled to obtain 1,150.9 g of 3-(benzylideneamino)propyltriethoxysilane as a fraction having a boiling point of 164° C./0.4 kPa. Yield was 93%.

[Comparative Example 2]
The reaction was carried out in the same manner as in Comparative Example 1, except that 717.2 g (4.0 mol) of 3-aminopropyltriethoxysilane was changed to 885.6 g (4.0 mol) of 3-aminopropyltriethoxysilane. Furthermore, the reaction liquid was distilled to obtain 1,001.5 g of 3-(benzylideneamino)propyltriethoxysilane as a fraction having a boiling point of 164° C./0.4 kPa. Yield was 81%.

Claims (2)

General formula (1) below

(In the formula, R ¹ represents a hydrogen atom or an m-valent hydrocarbon group having 1 to 20 carbon atoms which may contain a heteroatom; R ² represents a hydrogen atom or a monovalent hydrocarbon group having 1 to 20 carbon atoms; group, and m represents an integer of 1 to 10.)
A carbonyl group-containing compound represented by
General formula (2) below

(wherein R ³ represents a divalent hydrocarbon group having 1 to 20 carbon atoms, R ⁴ and R ⁵ each independently represent a monovalent hydrocarbon group having 1 to 20 carbon atoms, and n is represents 0, 1 or 2.)
The following general formula (3) is reacted with an aminoorganoxysilane compound represented by

(In the formula, R ¹ to R ⁵ , m and n have the same meanings as above.)
A method for producing an imino group-containing organooxysilane compound represented by
Conducting the reaction without removing water produced as a by-product out of the reaction system, and removing the water after the reaction is completed ;
A method for producing an imino group-containing organooxysilane compound, wherein the step of removing water is carried out by removing a water layer separated into two layers by a liquid separation operation of the reaction solution . 2. The method for producing an imino group-containing organooxysilane compound according to claim 1 , wherein said ^R2 is a hydrogen atom.