JP7714973B2 - Method for producing organosilicon compounds - Google Patents

Description

The present invention relates to a method for producing organosilicon compounds.

A silane coupling agent has two or more different functional groups in one molecule and acts as a mediator to connect organic and inorganic materials that are normally difficult to bond together.
One of the functional groups of silane coupling agents is a hydrolyzable silyl group, which generates a silanol group in the presence of water, and this silanol group reacts with a hydroxyl group on the surface of an inorganic material to form a chemical bond with the surface of the inorganic material. Other functional groups are organic reactive groups such as vinyl groups, epoxy groups, amino groups, (meth)acrylic groups, and mercapto groups, which form chemical bonds with organic materials such as various synthetic resins.
Taking advantage of the properties of these reactive groups, silane coupling agents are widely used as modifiers for organic and inorganic resins, adhesion aids, various additives, and the like.

Among the uses of silane coupling agents, organosilicon compounds containing blocked isocyanate groups have attracted attention as additives to coating compositions, pressure-sensitive adhesive compositions, and adhesive compositions, as well as treatment agents for fillers such as silica (Patent Documents 1 to 3).

An organosilicon compound having a blocked isocyanate group can be obtained by reacting an organosilicon compound having an isocyanate group with a blocking agent. The organosilicon compound having an isocyanate group is a liquid, and the blocking agent is a solid, resulting in a solid-liquid reaction.
In Patent Document 3, an organosilicon compound having an isocyanate group is reacted with 3,5-dimethylpyrazole, a blocking agent, all at once. When the reaction scale is increased, it becomes difficult to control heat generation, and when the reaction temperature becomes high, side reactions proceed, resulting in a decrease in purity. Furthermore, because this is a solid-liquid reaction, there is a risk of solids remaining if stirring is insufficient. Furthermore, when a solid is charged first, it is difficult to confirm the temperature in the reaction system.
In Patent Document 4, since a solvent is used, insufficient stirring is unlikely to occur, but a step of removing the solvent after the reaction is required, which results in a problem of low productivity.

Japanese Patent Application Laid-Open No. 2021-31620 Japanese Patent Application Laid-Open No. 2019-210364 Japanese Patent Application Laid-Open No. 2019-131677 JP 2009-256582 A

The present invention was developed in consideration of the above circumstances, and aims to provide a method for producing a blocked isocyanate group-containing organosilicon compound that allows for easy temperature control, is highly safe, and has a low content of by-products.

As a result of extensive research aimed at solving the above problems, the inventors discovered that safety and productivity can be improved when producing blocked isocyanate group-containing organosilicon compounds by first reacting a small amount of an isocyanate group-containing organosilicon compound with a blocking agent and then reacting the remaining isocyanate group-containing organosilicon compound with a blocking agent, or by carrying out the reaction of the isocyanate group-containing organosilicon compound with a blocking agent in the presence of a separately prepared blocked isocyanate group-containing organosilicon compound, and thus completed the present invention.

That is, the present invention provides:
1. The following formula (1)
(In the formula, each R ¹ independently represents an alkyl group having 1 to 8 carbon atoms; L represents a divalent linking group; X represents -O- or -NR ² -; Z represents a hydrogen atom or a monovalent organic group; R ² represents a hydrogen atom, an alkyl group having 1 to 8 carbon atoms, or a group capable of forming a ring structure by bonding with Z; and m represents an integer of 1 to 3.)
A method for producing an organosilicon compound represented by the formula:
(I): Formula (2) below
(wherein R ¹ , L and m are the same as defined above.)
and a compound represented by the following formula (3):
(In the formula, X and Z are the same as above.)
(II): supplying a compound represented by formula (2) to a mixture containing the compound represented by formula (1) and an unreacted compound represented by formula (3) obtained in step (I), and reacting the compound represented by formula (2) with the unreacted compound represented by formula (3) to obtain the organosilicon compound represented by formula (1);
2. The method for producing an organosilicon compound according to 1, wherein in step (II), the mixture containing the compound represented by formula (1) obtained in step (I) and the unreacted compound represented by formula (3) is a solution.
3. The method for producing an organosilicon compound according to 1 or 2, wherein in step (I), the amount of the compound represented by formula (2) added is 1 to 80 mol % of the total amount of steps (I) and (II) combined;
4. The following formula (1)
(In the formula, each R ¹ independently represents an alkyl group having 1 to 8 carbon atoms; L represents a divalent linking group; X represents -O- or -NR ² -; Z represents a hydrogen atom or a monovalent organic group; R ² represents a hydrogen atom, an alkyl group having 1 to 8 carbon atoms, or a group capable of forming a ring structure by bonding with Z; and m represents an integer of 1 to 3.)
A method for producing an organosilicon compound represented by the formula:
The following formula (2)
(wherein R ¹ , L and m are the same as defined above.)
and a compound represented by the following formula (3):
(In the formula, X and Z are the same as above.)
in the presence of a separately prepared organosilicon compound represented by formula (1),
5. The method for producing an organosilicon compound according to 4, wherein a solution prepared separately by dissolving a compound represented by formula (3) in an organosilicon compound represented by formula (1) is mixed with the compound represented by formula (2) to cause a reaction.
6. The present invention provides a method for producing an organosilicon compound according to any one of 1 to 5, wherein L is a trimethylene group and X is a group represented by —NR ² — (wherein R ² is the same as defined above).

The manufacturing method of the present invention enables temperature control even on a large scale in the production of blocked isocyanate group-containing organosilicon compounds, is highly safe, and suppresses the production of by-products, resulting in high productivity.

The present invention will be specifically described below.
[First manufacturing method]
The first method of the present invention for producing an organosilicon compound represented by the following formula (1) comprises the following steps (I) and (II).
(I): A step of reacting (a part of) a compound represented by the following formula (2) with a compound represented by the following formula (3) to obtain an organosilicon compound represented by the following formula (1): (II): A step of supplying (the remainder of) a compound represented by the following formula (2) to a mixture containing the compound represented by the following formula (1) and the unreacted compound represented by the following formula (3) obtained in step (I), and reacting this compound represented by the formula (2) with the unreacted compound represented by the following formula (3) to obtain an organosilicon compound represented by the following formula (1):

In formula (1), each R ¹ independently represents an alkyl group having 1 to 8 carbon atoms, preferably 1 to 6 carbon atoms; L represents a divalent linking group; X represents -O- or -NR ² -; Z represents a hydrogen atom or a monovalent organic group; R ² represents a hydrogen atom, an alkyl group having 1 to 8 carbon atoms, or a group capable of forming a ring structure by bonding with Z; and m represents an integer of 1 to 3, preferably 3.

The alkyl group having 1 to 8 carbon atoms for R ¹ may be linear, branched, or cyclic, and specific examples thereof include methyl, ethyl, n-propyl, isopropyl, n-butyl, isobutyl, tert-butyl, n-pentyl, neopentyl, n-hexyl, cyclohexyl, n-heptyl, and n-octyl groups. Among these, R ¹ is preferably an alkyl group having 1 to 3 carbon atoms, and more preferably a methyl group or an ethyl group.

Specific examples of the divalent linking group for L include alkylene groups, -O-, -S-, -NR-, -C(=O)-, -C(=O)-O-, -NRCO-, _-SO2- , and combinations thereof. Here, R represents a hydrogen atom or an alkyl group having 1 to 4 carbon atoms, preferably a hydrogen atom. Examples of the alkyl group include those having 1 to 4 carbon atoms among the alkyl groups exemplified above.
Among these, in view of the availability of raw materials when producing organosilicon compounds, the divalent linking group for L is preferably an alkylene group represented by -( _CH2 ) _n- (n is an integer of 1 to 10, preferably 1 to 6, more preferably 1 to 4), or a group in which one or more methylene units of this -( _CH2 ) _n- are replaced by -O-, -S-, -NH-, -C(=O)- and -C(=O)-O-, with -( _CH2 ) _3- (trimethylene group) being more preferred.

X in formula (1) is --O-- or --NR ² --, but is not particularly limited, since it is a group that forms part of the protecting group of the blocked isocyanate silane compound and is eliminated by heating.
In —NR ² — of X, R ² represents a hydrogen atom, an alkyl group having 1 to 8 carbon atoms, or a group capable of forming a ring structure by bonding with Z.
Examples of the alkyl group having 1 to 8 carbon atoms for ^R2 include the same groups as those exemplified for ^R1 above. Among these, a linear or branched alkyl group having 1 to 5 carbon atoms is preferred, and a methyl group or an ethyl group is more preferred.
In —NR ² —, when R ² represents a group capable of forming a ring structure by bonding with Z, —NR ² — preferably forms a heterocyclic structure together with X in formula (1). The heteroatom in such a heterocyclic structure preferably contains two or more nitrogen atoms, more preferably two nitrogen atoms. The heterocyclic structure is preferably a five- or six-membered ring structure, more preferably a five-membered ring structure.

Z in formula (1) is a hydrogen atom or a monovalent organic group, but is not particularly limited because it is a group that forms part of the protecting group of the blocked isocyanate silane compound and is eliminated by heating.
Specific examples of the monovalent organic group for Z include a monovalent hydrocarbon group having 1 to 20 carbon atoms, which may have a substituent and may contain an ether bond or an ester bond (excluding those containing O at the bond terminal with the oxygen atom to form an —O—O— bond), a hydroxyl group (excluding the case where X is —O—), and —N═R ⁵ (R ⁵ represents an alkylidene group having 1 to 10 carbon atoms which may be substituted with an aryl group or heteroaryl group having 6 to 20 carbon atoms).
The monovalent hydrocarbon group having 1 to 20 carbon atoms may be linear, branched, or cyclic, and examples thereof include alkyl groups having 1 to 20 carbon atoms, aryl groups having 6 to 20 carbon atoms, and aralkyl groups having 7 to 20 carbon atoms.
Specific examples of the alkyl group include the groups exemplified for R ¹ as well as n-nonyl, n-decyl, n-undecyl, n-dodecyl, n-tridecyl, and n-icosyl groups.
Specific examples of the aryl group include phenyl and naphthyl groups.
Specific examples of the aralkyl group include benzyl and phenylethyl groups.
In addition, at least a portion of the hydrogen atoms of these groups may be substituted with other substituents, such as a carboxyl group, a hydroxyl group, an oxo group (═O), or a thioxo group (═S).
In the above formula -N= ^R5 , ^the alkylidene group having 1 to 10 carbon atoms which may be substituted with an aryl group or heteroaryl group having 6 to 20 carbon atoms for R5 may be linear, branched, or cyclic, and specific examples thereof include methylidene, ethylidene, propylidene, propan-2-ylidene, butylidene, butan-2-ylidene, pentylidene, 4-methylpentan-2-ylidene, hexylidene, cyclohexylidene, heptylidene, octylidene, nonylidene, and decylidene groups.
Specific examples of the aryl group having 6 to 20 carbon atoms include the same groups as those exemplified above as the monovalent hydrocarbon group.
Specific examples of heteroaryl groups having 6 to 20 carbon atoms include pyrrol-1-yl, 1H-pyrrol-2-yl, imidazol-1-yl, imidazol-2-yl, pyrazol-1-yl, pyrazol-3-yl, pyridin-2-yl, and pyridin-3-yl groups.
Specific examples of the substituted alkylidene group include phenylmethylidene and diphenylmethylidene groups.

Of the organosilicon compounds represented by formula (1) above, those represented by formula (4) below are particularly preferred.

(wherein R ¹ , R ² , Z and m are the same as defined above.)

Specific examples of ^R2 and Z are the same as those mentioned above, but it is particularly preferred that they be bonded to each other to form a ring structure together with the nitrogen atom to which ^R2 and Z are bonded. Specific examples of the ring structure are preferably an imidazole ring, a pyrazole ring, a 1,2,3-triazole ring, or a 1,2,4-triazole ring, and more preferably a pyrazole ring.
The ring structure may have a substituent such as an alkyl group having 1 to 20 carbon atoms, an aryl group having 6 to 20 carbon atoms, an aralkyl group having 7 to 20 carbon atoms, a carboxyl group, a hydroxyl group, an ester group, an oxo group (═O), a halogen group such as chlorine or bromine, or a nitro group.
Suitable ring structures include, but are not limited to, the following:

(In the formula, the wavy line represents the bond site.)

Specific preferred examples of organosilicon compounds represented by formula (1) include, but are not limited to, the following:

(In the formula, Me represents a methyl group, and Et represents an ethyl group.)

Specific examples of organosilicon compounds represented by formula (2) used in the manufacturing method of the present invention include 1-isocyanatemethyltrimethoxysilane, 1-isocyanatemethyltriethoxysilane, 3-isocyanatepropyltrimethoxysilane, 3-isocyanatepropyltriethoxysilane, 3-isocyanatepropylmethyldimethoxysilane, 3-isocyanatepropylmethyldiethoxysilane, 6-isocyanatehexyltrimethoxysilane, 6-isocyanatehexyltriethoxysilane, 8-isocyanateoctyltrimethoxysilane, and 8-isocyanateoctyltriethoxysilane.

Specific examples of the compound represented by formula (3) include oxime-based compounds such as acetone oxime, methyl ethyl ketoxime, methyl isobutyl ketone oxime, cyclohexanone oxime, and benzophenone oxime; phenol-based compounds such as phenol, para-tert-butylphenol, and cresol; n-butanol, 2-ethylhexanol, phenyl carbinol, methylphenyl carbinol, ethylene glycol monomethyl ether, ethylene glycol monoethyl ether, ethylene glycol, ethylene glycol monobutyl ether, diethylene glycol monoethyl ether, and propylene glycol. Alcohol-based compounds such as glycerol, propylene glycol monomethyl ether, and methoxymethanol; lactam-based compounds such as ε-caprolactam and γ-butyrolactam; pyrrole-based compounds such as pyrrole, 2H-pyrrole, 1-methylpyrrole, 2,4-dimethylpyrrole, 2,5-dimethylpyrrole, and N-methylpyrrole; indole-based compounds such as indole, N-methylindole, and 2-methylindole, pyrazole, 3-methylpyrazole, 3,5-dimethylpyrazole, 4-bromo-3,5-dimethylpyrazole, 4-nitro-3,5-dimethylpyrazole, and 4-benzyl-3,5-dimethylpyrazole, Pyrazole compounds such as methyl-5-methylpyrazole-3-carboxylate, 3-methyl-5-phenylpyrazole, and 3,5-dimethylpyrazole-4-carboxyanilide; acid amide compounds such as acetanilide, acetanisidide, acetotoluide, acrylamide, methacrylamide, acetic amide, stearic acid amide, and benzamide; imide compounds such as succinimide, phthalic acid imide, and maleic acid imide; diphenylamine, phenylnaphthylamine, xylidine, N-phenylxylidine, carbazole, aniline, naphthylamine, butylamine, dibutylamine, and butylphenylamine. amine-based compounds; imidazole-based compounds such as imidazole, 2-methylimidazole, 2-ethylimidazole, 2-undecylimidazole, and benzimidazole; triazole-based compounds such as 1,2,3-triazole, 1,2,4-triazole, and 1,2,3-benzotriazole; piperidine-based compounds such as piperidine, N-methylpiperidine, and 4-methylpiperidine; urea-based compounds such as urea, thiourea, ethyleneurea, ethylenethiourea, and diphenylurea; carbamate-based compounds such as N-phenylphenylcarbamate; and imine-based compounds such as ethyleneimine and propyleneimine.
In addition to the above compounds, active methylene compounds such as dimethyl malonate, diethyl malonate, diisopropyl malonate, ethyl acetoacetate, isopropyl acetoacetate, methyl acetoacetate, isopropyl acetoacetate, and acetylacetone; mercaptan compounds such as n-butyl mercaptan, tert-butyl mercaptan, n-hexyl mercaptan, tert-dodecyl mercaptan, 2-mercaptobenzothiazole, thiophenol, methylthiophenol, and ethylthiophenol; and sulfite compounds such as sodium bisulfite and potassium bisulfite can also be used.
These may be used alone or in combination of two or more. Among these, as the compound represented by formula (3), lactam compounds, pyrazole compounds, pyrrole compounds, indole compounds, imidazole compounds, triazole compounds, and piperidine compounds are preferred, and the following compounds are more preferred:

Unlike a method of reacting a compound represented by formula (2) (an isocyanate group-containing organosilicon compound) with a compound represented by formula (3) (a blocking agent) all at once, the first method of producing an organosilicon compound of formula (1) (a blocked isocyanate group-containing organosilicon compound) comprises two or more steps: (i) reacting a portion of the compound represented by formula (2) with a compound represented by formula (3) to produce the organosilicon compound represented by formula (1); (ii) adding a compound represented by formula (2) to a mixture (preferably a solution) containing the resulting compound represented by formula (1) and unreacted compound represented by formula (3) and reacting it with the unreacted compound represented by formula (3); and (iii) producing the organosilicon compound represented by formula (1). If necessary, a compound represented by formula (2) is then added and reacted with the unreacted compound represented by formula (3). In the present invention, the reaction is preferably carried out in two steps, steps (I) and (II).

[1] First Step: Step (I) is a step of reacting an isocyanate group-containing organosilicon compound represented by the above formula (2) with a blocking agent represented by the above formula (3) to obtain a blocked isocyanate group-containing organic compound represented by the above formula (1).
In the reaction between the isocyanate group-containing organosilicon compound represented by formula (2) and the blocking agent represented by formula (3), the solid blocking agent represented by formula (3) is hardly soluble in the isocyanate group-containing organosilicon compound represented by formula (2), making it difficult to control the heat generated by this exothermic reaction. Therefore, in this step, a portion of the isocyanate group-containing organosilicon compound represented by formula (2) is reacted in advance with the blocking agent represented by formula (3) to produce the blocked isocyanate group-containing organosilicon compound represented by formula (1). This allows the compound represented by formula (1) to act as a compatibilizer, dissolving the blocking agent represented by formula (3), making it possible to easily control the temperature in the reaction system in step (II).

In step (I), the method for mixing the isocyanate group-containing organosilicon compound represented by formula (2) with the blocking agent represented by formula (3) is not particularly limited, but a preferred method is to add the solid blocking agent represented by formula (3) to the liquid isocyanate group-containing organosilicon compound represented by formula (2) while stirring it in air or an inert gas atmosphere such as nitrogen or argon. This method allows the reaction to be carried out while measuring the temperature of the reaction system, thereby ensuring greater safety.
In this case, from the viewpoint of improving productivity and suppressing side reactions, the time required for supplying the blocking agent represented by the above formula (3) is preferably 0.5 to 30 hours, more preferably 0.5 to 10 hours, and even more preferably 0.5 to 5 hours.

From the viewpoint of improving productivity and suppressing side reactions, the reaction temperature in step (I) is preferably 0 to 150°C, more preferably 20 to 130°C, and even more preferably 30 to 90°C.

In the first production method of the present invention, the ratio of the isocyanate group-containing organosilicon compound represented by formula (2) above to the blocking agent represented by formula (3) above is preferably 0.7 to 1.3 moles, and more preferably 0.8 to 1.2 moles, of the compound represented by formula (3) above per 1 mole of the isocyanate group-containing organosilicon compound represented by formula (2) above, in terms of the total amount used in all steps.

In step (I), the amount of the isocyanate group-containing organosilicon compound represented by formula (2) above used is preferably 1 to 80 mol %, more preferably 5 to 50 mol %, and even more preferably 10 to 45 mol %, of the total amount used in all steps, particularly steps (I) and (II) combined. Within this range, the heat generated by the reaction in step (I) will not be too great, and the temperature in the reaction system in step (II) will also be easily controlled.

In step (I), an organic solvent can be used if necessary, but it is preferable to carry out the reaction without a solvent. If no solvent is used, there is no need for a step to remove the organic solvent, which can further increase productivity.

[2] Second Step Step (II) is a step of supplying the remaining isocyanate group-containing organosilicon compound represented by formula (2) to the mixture containing the blocked isocyanate group-containing organic compound represented by formula (1) obtained in step (I) and the unreacted blocking agent represented by formula (3), and reacting the remaining isocyanate group-containing organosilicon compound represented by formula (2) with the blocking agent represented by formula (3).
Step (II) is preferably carried out after 50 mol % or more of the isocyanate group-containing organosilicon compound represented by formula (2) used in step (I) has reacted, and more preferably after 80 mol % or more of the isocyanate group-containing organosilicon compound has reacted.
After step (I), the mixture may be removed from the reaction vessel and transferred to another vessel, and step (II) may be carried out therein. However, it is preferable to carry out step (II) immediately after step (I) in the same reaction vessel.

There are no particular limitations on the method for supplying the isocyanate group-containing organosilicon compound represented by formula (2). However, from the standpoint of temperature control, it is preferable to supply it continuously at a constant rate by immersion in the liquid, dropwise addition, or the like, or to add it in multiple batches.

Furthermore, in step (II), from the viewpoint of improving productivity and suppressing side reactions, the time required for supplying the isocyanate group-containing organosilicon compound represented by formula (2) above is preferably 1 to 30 hours, more preferably 1 to 10 hours, and even more preferably 2 to 5 hours.
The reaction temperature in step (II) is preferably 0 to 150°C, more preferably 20 to 130°C, and even more preferably 30 to 90°C, from the viewpoints of improving productivity and suppressing side reactions, as in step (I) above.

In step (II), an organic solvent can be used if necessary, but it is preferable to carry out the reaction without a solvent. If no solvent is used, there is no need for a step to remove the organic solvent, which can further increase productivity.

[Second manufacturing method]
The method of the present invention for producing an organosilicon compound represented by the above formula (1) may also involve reacting an isocyanate group-containing organosilicon compound represented by the above formula (2) with a blocking agent represented by the above formula (3) in the presence of a separately prepared organosilicon compound represented by the above formula (1).
The reaction can be carried out, for example, by reacting a compound represented by formula (2) with a blocking agent represented by formula (3) under air or an inert gas atmosphere such as nitrogen or argon, and then adding a separately prepared organosilicon compound represented by formula (1) to the reaction system (reacting the compounds in the presence of a blocked isocyanate group-containing organic compound). The compound represented by formula (1) acts as a compatibilizer, dissolving the blocking agent represented by formula (3). The addition of a liquid compound represented by formula (1) facilitates temperature control, making it possible to easily control the temperature during the reaction. The reaction is preferably carried out by mixing a solution of the organosilicon compound represented by formula (1) with the blocking agent represented by formula (3), with the compound represented by formula (2).

The organosilicon compound represented by the above formula (1) to be added is preferably the same as the target organosilicon compound, and may be one prepared in advance from the isocyanate group-containing organosilicon compound represented by the above formula (2) and the blocking agent represented by the above formula (3), or a commercially available product may be used.
The amount of addition is not particularly limited, but is preferably 3 to 50% by mass, more preferably 5 to 40% by mass, based on the total amount of reaction raw materials.

In the second production method of the present invention, the ratio of the isocyanate group-containing organosilicon compound represented by the above formula (2) to the blocking agent represented by the above formula (3) is the same as in the first production method.
The reaction temperature is preferably 0 to 150°C, more preferably 20 to 130°C, and even more preferably 30 to 90°C, from the viewpoint of improving productivity and suppressing side reactions.

The organosilicon compound represented by formula (1) is preferably present in the reaction system from the start of the reaction between the isocyanate group-containing organosilicon compound represented by formula (2) and the blocking agent represented by formula (3). It is particularly preferable to mix the blocking agent represented by formula (3) and the organosilicon compound represented by formula (1) and then add the isocyanate group-containing organosilicon compound represented by formula (2) to cause the reaction. In this case, the method for adding the isocyanate group-containing organosilicon compound represented by formula (2) is preferably a method of continuously supplying it at a constant rate, such as by dropwise addition. From the perspectives of improving productivity and suppressing side reactions, the time required for supplying the isocyanate group-containing organosilicon compound represented by formula (2) is preferably 1 to 30 hours, more preferably 1 to 10 hours, and even more preferably 2 to 5 hours.

In addition, in the above production method, an organic solvent can be used if necessary, but it is preferable to carry out the reaction without a solvent. If a solvent is not used, there is no need for a step to remove the organic solvent, which can further increase productivity.

The present invention will be explained in more detail below with reference to examples and comparative examples, but the present invention is not limited to these examples.
The content of each organosilicon compound is an area percentage value determined by gel permeation chromatography (GPC). The viscosity is a value measured at 25°C using a rotational viscometer. The GPC measurement conditions are as follows:
Apparatus: HLC-8220 GPC (manufactured by Tosoh Corporation)
Column: TSKgel GMHXL-L (manufactured by Tosoh Corporation)
TSKgel Super H4000 (manufactured by Tosoh Corporation)
TSKgel Super H2000 (manufactured by Tosoh Corporation)
Solvent: THF
Flow rate: 0.6ml/min
In the following examples, Me represents a methyl group, and Et represents an ethyl group.

[Example 1]
A 12,000 mL pressure reaction vessel purged with nitrogen was charged with 2,474 g (10 mol) of 3-isocyanatepropyltriethoxysilane (KBE-9007N, manufactured by Shin-Etsu Chemical Co., Ltd.), and while stirring, 2,463 g (30 mol) of 2-methylimidazole (manufactured by Tokyo Chemical Industry Co., Ltd.) was added over 1 hour while controlling the internal temperature to 30 to 60°C. Stirring was then continued for 1 hour, and the disappearance of the isocyanate groups was confirmed by IR measurement. The 2-methylimidazole dissolved, and the system became homogeneous.
Thereafter, 4948 g (20 mol) of 3-isocyanatepropyltriethoxysilane (KBE-9007N, manufactured by Shin-Etsu Chemical Co., Ltd.) was further added over 3 hours while controlling the internal temperature to 30 to 60° C. Thereafter, stirring was carried out for 1 hour, and disappearance of the isocyanate group was confirmed by IR measurement.
As a result of GPC analysis, the content of the organosilicon compound represented by the following formula (5) was 99.7%, and the content of the by-product represented by the following formula (6) was 0.0%.

[Example 2]
A 12,000 mL pressure reaction vessel purged with nitrogen was charged with 2,474 g (10 mol) of 3-isocyanatepropyltriethoxysilane (KBE-9007N, manufactured by Shin-Etsu Chemical Co., Ltd.), and while stirring, 3,543 g (30 mol) of benzimidazole (manufactured by Tokyo Chemical Industry Co., Ltd.) was added over 1 hour while controlling the internal temperature to 30 to 60°C. Stirring was then continued for 1 hour, and the disappearance of the isocyanate groups was confirmed by IR measurement. The benzimidazole dissolved, and the system became homogeneous.
Thereafter, 4948 g (20 mol) of 3-isocyanatepropyltriethoxysilane (KBE-9007N, manufactured by Shin-Etsu Chemical Co., Ltd.) was further added over 3 hours while controlling the internal temperature to 30 to 60° C. Thereafter, stirring was carried out for 1 hour, and disappearance of the isocyanate group was confirmed by IR measurement.
As a result of GPC analysis, the content of the organosilicon compound represented by the following formula (7) was 99.7%, and the content of the by-product represented by the following formula (6) was 0.0%.

[Example 3]
A 12,000 mL pressure reaction vessel purged with nitrogen was charged with 2,474 g (10 mol) of 3-isocyanatepropyltriethoxysilane (KBE-9007N, manufactured by Shin-Etsu Chemical Co., Ltd.), and 2,884 g (30 mol) of 3,5-dimethylpyrazole (manufactured by Tokyo Chemical Industry Co., Ltd.) was added over 1 hour while stirring, controlling the internal temperature to 30 to 60°C. Stirring was then continued for 1 hour, and the disappearance of the isocyanate groups was confirmed by IR measurement. The 3,5-dimethylpyrazole dissolved, and the system became homogeneous.
Thereafter, 4948 g (20 mol) of 3-isocyanatepropyltriethoxysilane (KBE-9007N, manufactured by Shin-Etsu Chemical Co., Ltd.) was further added over 3 hours while controlling the internal temperature to 30 to 60° C. Thereafter, stirring was carried out for 1 hour, and disappearance of the isocyanate group was confirmed by IR measurement.
As a result of GPC analysis, the content of the organosilicon compound represented by the following formula (8) was 99.8%, and the content of the by-product represented by the following formula (6) was 0.0%.

[Example 4]
A 12,000 mL pressure reaction vessel purged with nitrogen was charged with 2,474 g (10 mol) of 3-isocyanatepropyltriethoxysilane (KBE-9007N, manufactured by Shin-Etsu Chemical Co., Ltd.), and while stirring, 3,574 g (30 mol) of benzotriazole (manufactured by Tokyo Chemical Industry Co., Ltd.) was added over 1 hour while controlling the internal temperature to 30 to 60°C. Stirring was then continued for 1 hour, and the disappearance of the isocyanate group was confirmed by IR measurement. The benzotriazole dissolved, and the system became homogeneous.
Thereafter, 4948 g (20 mol) of 3-isocyanatepropyltriethoxysilane (KBE-9007N, manufactured by Shin-Etsu Chemical Co., Ltd.) was further added over 3 hours while controlling the internal temperature to 30 to 60° C. Thereafter, stirring was carried out for 1 hour, and disappearance of the isocyanate group was confirmed by IR measurement.
As a result of GPC analysis, the content of the organosilicon compound represented by the following formula (9) was 99.8%, and the content of the by-product represented by the following formula (6) was 0.0%.

[Example 5]
A 12,000 mL pressure reaction vessel purged with nitrogen was charged with 2,474 g (10 mol) of 3-isocyanatepropyltriethoxysilane (KBE-9007N, manufactured by Shin-Etsu Chemical Co., Ltd.), and while stirring, 3,395 g (30 mol) of caprolactam (manufactured by Tokyo Chemical Industry Co., Ltd.) was added over 1 hour while controlling the internal temperature to 70 to 90°C. Stirring was then continued for 1 hour, and the disappearance of the isocyanate groups was confirmed by IR measurement. The caprolactam dissolved, and the system became homogeneous.
Thereafter, 4948 g (20 mol) of 3-isocyanatepropyltriethoxysilane (KBE-9007N, manufactured by Shin-Etsu Chemical Co., Ltd.) was further added over 3 hours while controlling the internal temperature to 70 to 90° C. Thereafter, stirring was carried out for 1 hour, and disappearance of the isocyanate groups was confirmed by IR measurement.
As a result of GPC analysis, the content of the organosilicon compound represented by the following formula (10) was 99.8%, and the content of the by-product represented by the following formula (6) was 0.0%.

[Example 6]
A 12,000 mL pressure reaction vessel purged with nitrogen was charged with 2,053 g (10 mol) of 3-isocyanatepropyltrimethoxysilane (KBM-9007, manufactured by Shin-Etsu Chemical Co., Ltd.), and 2,463 g (30 mol) of 2-methylimidazole (manufactured by Tokyo Chemical Industry Co., Ltd.) was added thereto over 1 hour while stirring, while controlling the internal temperature to be 30 to 60° C. The 2-methylimidazole dissolved, and the system became homogeneous.
Thereafter, stirring was continued for 1 hour, and the disappearance of the isocyanate groups was confirmed by IR measurement. Thereafter, 4106 g (20 mol) of 3-isocyanatepropyltrimethoxysilane (KBM-9007, manufactured by Shin-Etsu Chemical Co., Ltd.) was further added over 3 hours while controlling the internal temperature to 30 to 60°C. Thereafter, stirring was continued for 1 hour, and the disappearance of the isocyanate groups was confirmed by IR measurement.
As a result of GPC analysis, the content of the organosilicon compound represented by the following formula (11) was 99.7%, and the content of the by-product represented by the following formula (12) was 0.0%.

[Example 7]
A 12,000 mL pressure reaction vessel purged with nitrogen was charged with 2,874 g of the product obtained in Example 6 above and 1,642 g (20 moles) of 2-methylimidazole (Tokyo Chemical Industry Co., Ltd.), and the vessel was stirred to dissolve the 2-methylimidazole. Then, 4,106 g (20 moles) of 3-isocyanatepropyltrimethoxysilane (KBM-9007, Shin-Etsu Chemical Co., Ltd.) was added over 3 hours while controlling the internal temperature to 30 to 60° C. The mixture was then stirred for 1 hour, and the disappearance of the isocyanate groups was confirmed by IR measurement.
As a result of GPC analysis, the content of the organosilicon compound represented by the following formula (11) was 99.7%, and the content of the by-product represented by the following formula (12) was 0.0%.

[Comparative Example 1]
A 12,000 mL pressure reaction vessel purged with nitrogen was charged with 2,463 g (30 mol) of 2-methylimidazole (Tokyo Chemical Industry Co., Ltd.), and 4,516 g (30 mol) of 3-isocyanatepropyltrimethoxysilane (KBM-9007, Shin-Etsu Chemical Co., Ltd.) was added dropwise over 1 hour while stirring the suspension. The internal temperature was 30 to 140°C. Stirring was then continued for 1 hour, and the disappearance of the isocyanate groups was confirmed by IR measurement.
As a result of GPC analysis, the content of the organosilicon compound represented by the following formula (11) was 97.5%, and the content of the by-product represented by the following formula (12) was 1.2%.

The manufacturing methods of Examples 1 to 7 above allow for easy temperature control, making it possible to obtain highly pure products. In contrast, the manufacturing method of Comparative Example 1 makes it difficult to control the temperature, resulting in high temperatures in the reaction system and a decrease in purity due to by-products.

Claims (5)

The following formula (1)
(In the formula, each ^R1 independently represents an alkyl group having 1 to 8 carbon atoms, L represents a divalent linking group, X represents -O- or ^-NR2- , Z represents a monovalent organic group, ^R2 represents a hydrogen atom, an alkyl group having 1 to 8 carbon atoms, or a group capable of forming a ring structure by bonding with Z, and m represents an integer of 1 to 3.)
A method for producing an organosilicon compound represented by the formula:
(I): Formula (2) below
(wherein R ¹ , L and m are the same as defined above.)
and a compound represented by the following formula (3):
(In the formula, Z represents a monovalent organic group, and X is the same as defined above.)
(II): supplying a compound represented by formula (2) to the mixture containing the compound represented by formula (1) and the unreacted compound represented by formula (3) obtained in step (I), and reacting this compound represented by formula (2) with the unreacted compound represented by formula (3) to obtain the organosilicon compound represented by formula (1),
In the step (I), the amount of the compound represented by formula (2) added is 1 to 80 mol % of the total amount of the steps (I) and (II) combined. The method for producing an organosilicon compound according to claim 1, wherein in step (II), the mixture containing the compound represented by formula (1) obtained in step (I) and the unreacted compound represented by formula (3) is in the form of a solution. The following formula (1)
(In the formula, each ^R1 independently represents an alkyl group having 1 to 8 carbon atoms, L represents a divalent linking group, X represents -O- or ^-NR2- , Z represents a monovalent organic group, ^R2 represents a hydrogen atom, an alkyl group having 1 to 8 carbon atoms, or a group capable of forming a ring structure by bonding with Z, and m represents an integer of 1 to 3.)
A method for producing an organosilicon compound represented by the formula:
The following formula (2)
(wherein R ¹ , L and m are the same as defined above.)
and a compound represented by the following formula (3):
(In the formula, Z represents a monovalent organic group, and X is the same as defined above.)
in the presence of a separately prepared organosilicon compound represented by formula (1). The method for producing an organosilicon compound according to claim 3, wherein a solution prepared separately by dissolving a compound represented by formula (3) in an organosilicon compound represented by formula (1) is mixed with the compound represented by formula (2) to cause the reaction. 5. The method for producing an organosilicon compound according to claim 1, wherein L is a trimethylene group and X is a group represented by --NR ² -- (wherein R ² is the same as defined above).