JP6906983B2 - Acetylene-containing benzoxazine compound, polyacetylene compound obtained by polymerizing the ethynyl group of the acetylene-containing benzoxazine compound, and a thermocured product thereof. - Google Patents

Description

The present invention relates to a novel acetylene-containing benzoxazine compound, a polyacetylene compound obtained by polymerizing an ethynyl group of the acetylene-containing benzoxazine compound, and a thermocured product of the polyacetylene compound.

The benzoxazine compound refers to a compound containing a benzoxazine ring having a benzene skeleton and an oxazine skeleton, and the benzoxazine resin, which is a cured product (polymer) thereof, has excellent physical properties such as heat resistance and mechanical strength, and has many properties. It is used as a high-performance material for various applications in various fields.

Patent Document 1 discloses a benzoxazine compound having a specific structure and a method for producing the same, and describes that the benzoxazine compound can be used to produce a cured benzoxazine resin having a high thermal conductivity.

Patent Document 2 discloses a thermosetting resin in which a part or all of the reactive ends of a polybenzoxazine resin having a specific benzoxazine ring structure in the main chain is sealed, and the thermosetting resin is used as a solvent. It describes that it is excellent in storage stability when dissolved.

By the way, polyacetylene is known as a conjugated conductive polymer, and since it is an organic conductor, it is expected to be used in various applications. In recent years, it has also been reported that polyacetylene has excellent thermal conductivity (Non-Patent Document 1).

Attempts have also been made to introduce an acetylene group into the above-mentioned benzoxazine compound. For example, Non-Patent Document 2 describes a compound in which an acetylene group is introduced into the nitrogen atom of the oxazine ring of benzoxazine via a phenyl group, and a cured product of a benzoxazine compound having such an acetylene functional group is described. , Has been reported to have high heat resistance.

Japanese Unexamined Patent Publication No. 2013-60407 Japanese Unexamined Patent Publication No. 2012-36318

Development of Highly Conductive Composite Polymers Journal of the Japanese Society of Adhesion, Vol. 43, p. 325 (2007) Polymer 6565, 40 (1999)

It is considered that the benzoxazine compound described in Non-Patent Document 2 described above can be obtained as a cured product having a crosslinked structure by polymerizing an acetylene functional group and ring-opening polymerization of benzoxazine. However, in the cured product having the above-mentioned structure, when thermal decomposition occurs in a high temperature environment, polyacetylene and polybenzoxazine are cleaved with desorption of the aniline compound, resulting in a decrease in crosslink density. It is expected that the heat resistance of the cured product will decrease. Then, if an acetylene functional group is introduced into the benzene ring instead of the oxazine ring of benzoxazine, it can be expected that the heat resistance of the cured product will be improved.

Therefore, the present invention provides a novel acetylene-containing benzoxazine compound which can be expected to have high thermal conductivity by containing a polyacetylene portion in addition to obtaining a highly heat-resistant cured product having a high glass transition temperature and being hard to be thermally decomposed. The purpose is to provide.

Another object of the present invention is to provide a polyacetylene compound obtained by polymerizing the ethynyl group of the acetylene-containing benzoxazine compound, and a thermosetting product of the polyacetylene compound.

As a result of diligent studies based on the above findings, the present inventors have developed a benzoxazine compound in which an acetylene functional group is introduced into a benzene ring instead of the oxazine ring of benzoxazine, and complete the present invention. It came to.

［式（Ｉ）中、
Ｒ¹は、水素、置換されていてもよいアルキル基、または置換されていてもよいアリール基を示し、
Ｒ^２は、置換されていてもよいアルキル基、または置換されていてもよいアリール基を示す。］。
（２）前記式（Ｉ）において、Ｒ¹が水素である、（１）に記載のアセチレン含有ベンゾオキサジン化合物。
（３）前記式（Ｉ）において、Ｒ^２がフェニル基である、（１）または（２）に記載のアセチレン含有ベンゾオキサジン化合物。
（４）（１）〜（３）のいずれかに記載のアセチレン含有ベンゾオキサジン化合物のエチニル基を重合させてなるポリアセチレン化合物。
（５）（４）に記載のポリアセチレン化合物を含む組成物の熱硬化物。 According to the present invention, the following inventions are provided.
(1) An acetylene-containing benzoxazine compound represented by the following formula (I):

[In formula (I),
R ¹ represents hydrogen, an optionally substituted alkyl group, or an optionally substituted aryl group.
R ² represents an optionally substituted alkyl group or optionally substituted aryl group. ].
(2) The acetylene-containing benzoxazine compound according to (1), wherein ^{R 1} is hydrogen in the formula (I).
(3) The acetylene-containing benzoxazine compound according to (1) or (2), ^{wherein R 2} is a phenyl group in the above formula (I).
(4) A polyacetylene compound obtained by polymerizing the ethynyl group of the acetylene-containing benzoxazine compound according to any one of (1) to (3).
(5) A thermosetting product of the composition containing the polyacetylene compound according to (4).

The acetylene-containing benzoxazine compound according to the formula (I) of the present invention is a novel compound. Due to the structure represented by the formula (I), the polyacetylene compound obtained by polymerizing the benzoxazine compound of the present invention is characterized by having good heat resistance and thermal conductivity after curing. Therefore, the benzoxazine resin thermosetting using the benzoxazine compound of the present invention as a raw material is an adhesive, a sealing material (for example, a sealing material used in the electronic field), a laminated board, a paint, and a composite material. It can be used as a matrix resin for coating.

^{The 1} H-NMR spectrum of Compound 1 is shown. ^{The 1 1} H-NMR spectrum of compound 2 is shown. ^{The 13} C-NMR spectrum of Compound 2 is shown. ^{The 1 1} H-NMR spectrum of compound 3 is shown. ^{The 13} C-NMR spectrum of Compound 3 is shown. The FT-IR spectrum of compound 3 is shown. The size exclusion chromatography chart of a polyacetylene compound is shown. The Raman spectrum of the polyacetylene compound is shown. The IR spectrum before and after heating of the polyacetylene compound is shown.

Specific description of the invention

上記式（Ｉ）中、Ｒ^１は、水素、置換されていてもよいアルキル基、または置換されていてもよいアリール基を示す。また、Ｒ^２は、置換されていてもよいアルキル基、または置換されていてもよいアリール基を示す。なお、本明細書において、「エチニル基」とは、−Ｃ≡ＣＨに限られず、−Ｃ≡Ｃ−Ｒ^１（式中のＲ^１は上記で定義されるものである）で表される官能基を包含するものとする。 Hereinafter, the present invention will be described in detail.
<Acetylene-containing benzoxazine compound>
The acetylene-containing benzoxazine compound according to the present invention is represented by the following formula (I).

In formula (I) above, R ¹ represents hydrogen, an optionally substituted alkyl group, or an optionally substituted aryl group. Further, R ² indicates an alkyl group which may be substituted or an aryl group which may be substituted. In the present specification, represented by the term "ethynyl" is not limited to ^{-C≡CH, -C≡C-R 1 (R} 1 in the formula is as defined above) functional It shall include groups.

なお、式（Ｉａ）および（Ｉｂ）中のＲ^１およびＲ^２の定義は上記と同様である。 The acetylene-containing benzoxazine compound of the formula (I) is a benzoxazine in which acetylene substituted on the benzene ring of the benzoxazine ring is bound. Therefore, specific examples of the benzoxazine compound of the formula (I) (hereinafter, may be simply referred to as the compound of the formula (I)) include the benzoxazine compound group of the following formulas (Ia) and (Ib). Can be done.

^{The definitions of R 1} and R ^{2 in} the formulas (Ia) and (Ib) are the same as above.

In the present invention, the ^{"alkyl group" represented by R 1} in the formula (I) is not particularly limited in number of carbon atoms, but is preferably 1 to 6 (except when substituted). .. The alkyl group may be either linear or branched.
Specific examples of the alkyl group indicated by R ¹ include a methyl group, an ethyl group, an n-propyl group, an i-propyl group, an n-butyl group, an i-butyl group, an s-butyl group, a t-butyl group, and a pentyl group. , Hexyl group and the like, preferably a methyl group and an ethyl group.

The ^{alkyl group represented by R 1} may be substituted, and examples thereof include at least one group selected from the group consisting of an ether group, an amide group, an ester group, an aryl group, an alkoxy group and a halogen atom. It is preferably an ether group, an amide group, or an aryl group.
Specific examples of the substituted alkyl group indicated by R ¹ include a benzyl group, a phenethyl group, a trityl group, a methoxymethyl group, an ethoxymethyl group, a phenoxymethyl group, a phenoxyethyl group, an acetamide methyl group, an acetoxymethyl group and the like. , And preferably a benzyl group, a methoxymethyl group, an ethoxymethyl group, and a phenoxymethyl group.

In the present specification, the ^{"aryl group" represented by R 1} in the formula (I) is not particularly limited in number of carbon atoms, but is preferably 6 to 10 (except when substituted). ).
Specific examples of the aryl group indicated by R ¹ include a phenyl group, a naphthyl group and the like, and a phenyl group is preferable.

The ^{aryl group represented by R 1} may be substituted, and as the substituent, at least one selected from the group consisting of an alkyl group, an ether group, an amide group, an ester group, an aryl group, an alkoxy group and a halogen atom. Groups are mentioned, preferably alkyl groups.
Specific examples of the substituted aryl group indicated by R ¹ include an o-tolyl group, an m-tolyl group, a p-tolyl group, a xylyl group, a methylnaphthyl group, an ethylnaphthyl group, a dimethylnaphthyl group, and a methoxyphenyl group. , Phenoxyphenyl group, acetamidephenyl group, acetoxyphenyl group and the like, preferably a tolyl group, a xsilyl group, a methylnaphthyl group, a methoxyphenyl group, a phenoxyphenyl group and the like.

In the present invention, the ^{"alkyl group" represented by R 2} in the formula (I) is not particularly limited in number of carbon atoms, but is preferably 1 to 6 (except when substituted). .. The alkyl group may be either linear or branched.
Specific examples of the alkyl group indicated by R ² include a methyl group, an ethyl group, an n-propyl group, an i-propyl group, an n-butyl group, an i-butyl group, an s-butyl group, a t-butyl group, and a pentyl group. , Hexyl group and the like, preferably a methyl group and an ethyl group.

The ^{alkyl group represented by R 2} may be substituted, and examples thereof include at least one group selected from the group consisting of an ether group, an amide group, an ester group, an aryl group, an alkoxy group and a halogen atom. It is preferably an ether group, an amide group, or an aryl group.
Specific examples of the substituted alkyl group shown by R ² include a benzyl group, a phenethyl group, a trityl group, a methoxymethyl group, an ethoxymethyl group, a phenoxymethyl group, a phenoxyethyl group, an acetamide methyl group, an acetoxymethyl group and the like. , And preferably a benzyl group, a methoxymethyl group, an ethoxymethyl group, and a phenoxymethyl group.

In the present specification, the expression "aryl group" represented by R ² in (I) is the number of carbon atoms is not particularly limited, preferably 6 to 10 (except as may be substituted ).
Specific examples of the aryl group shown by R ² include a phenyl group, a naphthyl group and the like, and a phenyl group is preferable.

The ^{aryl group represented by R 2} may be substituted, and as the substituent, at least one selected from the group consisting of an alkyl group, an ether group, an amide group, an ester group, an aryl group, an alkoxy group and a halogen atom. Examples thereof include an alkyl group, an ether group, an amide group, an aryl group and the like.
Specific examples of the substituted aryl group shown by R ² include an o-tolyl group, an m-tolyl group, a p-tolyl group, a xylyl group, a methylnaphthyl group, an ethylnaphthyl group, a dimethylnaphthyl group, and a methoxyphenyl group. , Phenoxyphenyl group, acetamidephenyl group, acetoxyphenyl group and the like, preferably a tolyl group, a xsilyl group, a methylnaphthyl group, a methoxyphenyl group, a phenoxyphenyl group and the like.

According to another preferred embodiment of the invention, R ¹ represents a hydrogen, alkyl group, or aryl group and R ² represents an optionally substituted aryl group.

According to another preferred embodiment of the invention, R ¹ represents a hydrogen or phenyl group and R ² represents a phenyl or naphthyl group.

<Method for producing acetylene-containing benzoxazine compound>
Next, a method for producing the acetylene-containing benzoxazine compound according to the present invention will be described.
The acetylene-containing benzoxazine compound can be obtained by a benzoxazine ring synthesis reaction. Specifically, the acetylene-containing benzoxazine compound according to the present invention can be produced by reacting an acetylene-containing phenol derivative with an amine compound and formaldehyde or a formaldehyde derivative. The following compound C can be used as the acetylene-containing phenol derivative used in the benzoxazine ring synthesis reaction. As a typical acetylene-containing phenol derivative used in the production method according to the present invention, 4- [2- (trimethylsilyl) ethynyl] benzene can be exemplified. As the amine ^compound, using a R 2 -NH _2. Aniline can be exemplified as a typical amine compound used in the production method according to the present invention. Further, the formaldehyde used in the benzoxazine ring synthesis reaction is typically formalin, and examples of the formaldehyde derivative include multimers such as 1,3,5-trioxane and paraformaldehyde, and polymers.

As one embodiment of the present invention, a specific example of a method for producing an acetylene-containing benzoxazine compound in which ^{R 1 is hydrogen in the above formula (I) is shown below, but the method is not limited to this method.}

Process (A):
First, compound C is synthesized by a reaction between a halogenated phenol (hereinafter, also referred to as compound A) and a compound in which one side of acetylene is substituted with a protecting group Y (hereinafter, also referred to as compound B). In each subsequent scheme, X represents a halogen atom such as chlorine, bromine, iodine, and Y represents a protecting group.

In step (A), a halogenated phenol (Compound A) and a compound (Compound B) in which one side of acetylene is substituted with a protective group Y are cupped in the presence of a catalyst in an atmosphere of an inert gas such as argon or nitrogen. By the ring reaction, a reaction product containing compound C can be obtained.

Examples of the compound (compound B) in which one side of the acetylene is substituted with the protecting group Y includes silane compounds such as trimethylsilyl-acetylene and triisopropylsilyl-acetylene, and the amount used is 1 mol of phenol halide. On the other hand, for example, it is 0.5 to 10 mol, preferably 1 to 3 mol.

The catalyst system in the coupling reaction is usually not limited as long as it is a catalyst system capable of forming a carbon-carbon bond, but is bis (triphenylphosphene) palladium for carrying out the Sonogashira coupling reaction. (II) It is preferable to use a catalyst system containing dichloride and copper iodide or a catalyst system containing tetrakis (triphenylphosphene) palladium, zinc bromide and triethylamine. The amount of bis (triphenylphosphine) palladium (II) dichloride added is not limited, but is, for example, 0.1 to 10 mol%, preferably 2 to 5 mol%, based on 1 mol of compound B. Mol%. The amount of copper iodide added is, for example, 1 to 10 mol, preferably 2 to 5 mol, based on 1 mol of bis (triphenylphosphine) palladium (II) dichloride.

The solvent used in the reaction includes, but is not limited to, a nitrogen compound such as diethylamine, triethylamine, butylamine, tributylamine, pyridine or piperidine, and ethers such as tetrahydrofuran. These solvents may be used alone or in combination of two or more. The amount used is preferably, for example, 1 to 100 times by weight, preferably 2 to 50 times by weight, that of the raw material. Further, these solvents are preferably distilled in advance in order to prevent side reactions and deactivation of the catalyst.

The reaction temperature at the time of carrying out the coupling reaction is not particularly limited, but from the viewpoint of the reaction rate, it may be, for example, a temperature range of 20 to 150 ° C., preferably a temperature range of 40 to 100 ° C. Or the reflux temperature. The reaction time may be, for example, 10 minutes to 48 hours, preferably 30 minutes to 24 hours.

In the reaction of Scheme 1, the reaction product containing compound C is purified by distillation, recrystallization, column chromatography purification, solvent washing, etc. according to a conventional method to obtain high-purity compound C as necessary. Is preferable. By the purification, compound D can be obtained in a high yield in the next step (a). Examples of the purification solvent include water, alcohols, hydrocarbons, aromatic hydrocarbons, ethers, esters, halogen-containing solvents, amines and the like.

Process (a):
Next, compound D is synthesized by reacting compound C obtained as described above with formaldehyde or a formaldehyde derivative with an amine compound. In each subsequent scheme, R ² is as shown in formula (I) and formaldehyde or formaldehyde derivative is shown as (CH ₂ O) _n .

Examples of the amine compound used in the benzoxazine ring synthesis reaction in step (a) include primary arylamines and primary alkylamines. Examples of the primary arylamine include aniline, 4-methylaniline, 1-naphthylamine, 2-naphthylamine and the like, and aniline and 1-naphthylamine are preferable. Regarding the amount of the amine compound used, the theoretical reaction molar ratio of the compound C and the amine compound is 1: 1. In the actual synthetic reaction, the amount of the amine compound used is preferably 0.3 to 2 mol, more preferably 0.8 to 1.5 mol, based on 1 mol of the compound C from the viewpoint of high yield. preferable.

Examples of formaldehyde or formaldehyde derivatives used in the benzoxazine ring synthesis reaction include 1,3,5-trioxane, formaldehyde, paraformaldehyde, formalin or a combination thereof, and preferably 1,3,5-trioxane. , Paraformaldehyde, formalin. The theoretical amount of _{formaldehyde or formaldehyde derivative used is 2 mol as CH 2} O with respect to 1 mol of compound C. In the actual synthetic reaction, the amount of formaldehyde or formaldehyde derivative used is preferably 1.0 to 6.0 mol, preferably 2.0 to 6.0 mol _{, of CH 2 O with respect to 1 mol of compound C from the viewpoint of high yield.} 4.0 mol is more preferred. Therefore, when 1,3,5-trioxane is used as the formaldehyde derivative, the amount used is preferably 0.3 to 2.0 mol with respect to 1 mol of compound C, and 0.6 to 1. 3 mol is more preferred.

Examples of the reaction solvent that can be used when carrying out the benzoxazine ring synthesis reaction include alcohols, aromatic hydrocarbons, ethers, esters, halogen-containing solvents and the like, from the viewpoint of solubility of the reactants and products. Therefore, aromatic hydrocarbons are preferable. Toluene is more preferable as the aromatic hydrocarbons.

The reaction temperature of the benzoxazine ring synthesis reaction is not particularly limited, but may be, for example, a temperature range of 20 to 150 ° C., preferably 20 to 100, from the viewpoint of the reaction rate and the boiling point of the reaction solvent. It is in the temperature range of ° C. The reaction time may be, for example, 30 minutes to 48 hours, preferably 1 to 24 hours.

In the reaction of Scheme 2, the reaction product containing compound D is purified by distillation, recrystallization, column chromatography purification, solvent washing, etc. according to a conventional method to obtain high-purity compound D as necessary. Is preferable. By the purification, compound E can be obtained in a high yield in the next step (c). Examples of the purification solvent include water, alcohols, hydrocarbons, aromatic hydrocarbons, ethers, esters, halogen-containing solvents and the like.

Process (c):
Subsequently, the protecting group of compound D obtained as described above is deprotected to obtain compound E.

In the reaction of Scheme 3, the deprotecting agent is not particularly limited, but when the protecting group is a silyl group such as trimethylsilyl or triisopropylsilyl, a base or a fluoride ion can be mentioned. Examples of the base include potassium carbonate and calcium carbonate, and examples of the fluoride ion include tetrabutylammonium fluoride, preferably tetrabutylammonium fluoride and calcium carbonate. It can also be carried out by adding an organic acid such as acetic acid. The amount of the deprotecting agent used may be, for example, 0.5 to 50 mol, preferably 5 to 20 mol, relative to 1 mol of compound E.

Examples of the reaction solvent for carrying out the deprotection reaction include an aprotic polar solvent and alcohols, and an aprotic polar solvent is preferable. Tetrahydrofuran is more preferable as the aprotic polar solvent.

The reaction temperature when the deprotection reaction is carried out is not particularly limited, but from the viewpoint of the reaction rate, a temperature range of 20 to 150 ° C. is preferable, and a temperature range of 20 to 100 ° C. is more preferable. The reaction time may be, for example, 1 minute to 10 hours, preferably 30 minutes to 5 hours.

In the reaction of Scheme 3, it is preferable that the reaction product containing the compound D is purified by recrystallization, column chromatography purification, solvent washing or the like according to a conventional method to obtain a high-purity compound E, if necessary. Examples of the purification solvent include water, alcohols, hydrocarbons, aromatic hydrocarbons, ethers, esters, halogen-containing solvents and the like.

Another embodiment of the present invention, the following specific examples of the method for manufacturing the above formula (I) in the acetylene-containing benzoxazine compound in which R ¹ is an aryl group which may be the alkyl group or substituted or optionally substituted However, the method is not limited to this method.

Process (d):
First, compound G is synthesized by a reaction between a halogenated phenol (compound A) and a compound in which one side of acetylene ^{is substituted with R 1} (hereinafter, also referred to as compound F). Note that in each subsequent Schemes, R ¹ and X are as described above.

In step (d), halogenated phenol (Compound A) with a compound on one side is substituted by R ¹ of acetylene and (Compound F), in the presence of a catalyst, argon, coupling in an inert gas atmosphere such as nitrogen By reacting, a reaction product containing compound G can be obtained. The amount of Compound F used is, for example, 0.5 to 10 mol, preferably 1 to 3 mol, based on 1 mol of the halogenated phenol.

As the catalyst system in the coupling reaction, the same one as described above can be used. Further, as the solvent used for the coupling reaction, the same solvent as those described above can be used. The reaction temperature at the time of carrying out the coupling reaction is not particularly limited, but from the viewpoint of the reaction rate, it may be, for example, a temperature range of 20 to 150 ° C., preferably a temperature of 40 to 100 ° C. Range or reflux temperature. The reaction time may be, for example, 10 minutes to 48 hours, preferably 30 minutes to 24 hours.

In the reaction of Scheme 4, it is preferable that the reaction product containing the compound G is purified by distillation, recrystallization, column chromatography purification, solvent washing, etc. according to a conventional method to obtain a high-purity compound G, if necessary. .. By the purification, compound H can be obtained in a high yield in the next step (e). Examples of the purification solvent include water, alcohols, hydrocarbons, aromatic hydrocarbons, ethers, esters, halogen-containing solvents, amines and the like.

Process (e):
Next, compound H is synthesized by reacting compound G obtained as described above with formaldehyde or a formaldehyde derivative with an amine compound. In each subsequent scheme, R ² and (CH ₂ O) _n are as described above.

Step amine compound used in the benzoxazine ring synthesis reaction (e) is R ² -NH _2, it can be used the same as described above, be the same as the above applies to the amount used Can be done. Further, the formaldehyde or formaldehyde derivative can also be the same as the one described above, and the amount used can be the same as the above. Further, the reaction conditions (solvent, temperature, time) of the benzoxazine ring synthesis reaction can be the same as described above.

In the reaction of Scheme 5, it is preferable that the reaction containing compound H is purified by distillation, recrystallization, column chromatography purification, solvent washing or the like according to a conventional method to obtain high-purity compound H, if necessary. Examples of the purification solvent include water, alcohols, hydrocarbons, aromatic hydrocarbons, ethers, esters, halogen-containing solvents and the like.

The acetylene-containing benzoxazine compound represented by the above formula (I) according to the present invention shall be identified by known analytical means such as ^{mass spectrum, infrared spectroscopy (IR), proton NMR (1} HNMR), and ^{13 CNMR.} Can be done. From the fact that the molecular weight matches the target substance in the mass spectrum, the spectrum has a specific characteristic absorption peak by IR measurement, and the chemical shift of the NMR peak by both NMR measurements, each hydrogen atom and carbon atom Compounds can be identified by being reasonably attributed. The specific identification method will be described with reference to the exemplified compounds of Examples described later.

In the acetylene-containing benzoxazine compound represented by the above formula (I) according to the present invention, for example, when R ¹ represents hydrogen and R ² represents a phenyl group, the molecular ion ([M) measured by mass spectrum is measured. ] ^{+ ·} ) Mass, i.e., molecular weight is 235. Further, by IR spectrum analysis, ^{the peak of 2101 cm -1} of the above compound shows the expansion and contraction vibration of the ethynyl group, and the peak of ^{3269 cm -1} shows the expansion and contraction vibration of the CH bond of the ethynyl group.

<Polyacetylene compound>
According to another embodiment of the present invention, a polyacetylene compound represented by the following formula (II) obtained by polymerizing the ethynyl group of the acetylene-containing benzoxazine compound represented by the formula (I) is also provided.

The polyacetylene compound represented by the above formula (II) can be obtained by polymerizing an ethynyl group using the compound of the above formula (I) as a raw material to obtain a polyacetylene compound of the formula (II). The polymerization method is not particularly limited as long as the effects of the present invention can be obtained, but solution polymerization is preferable. Solution polymerization is carried out in the presence of a catalyst by preparing a solution in which the acetylene-containing benzoxazine compound represented by the formula (I) is dissolved in water and / or an organic solvent. The concentration of the compound of formula (I) in the reaction solution is 0.00001 to 10 M, preferably 0.01 to 0.1 M. The polymerization temperature is in the range of −50 ° C. to 90 ° C., preferably 0 to 70 ° C. in the presence of a catalyst. A suitable polymerization reaction time is, for example, 0.5 minutes to 48 hours, preferably 30 minutes to 24 hours. The weight average molecular weight (Mw) is, for example, 10 to 1,000,000, preferably 5,000 to 100,000. The number average molecular weight (Mn) is, for example, 1,000 to 500,000, preferably 5,000 to 50,000. The molecular weight distribution (Mw / Mn) is, for example, 1 to 10, preferably 1.5 to 5. The weight average molecular weight and the molecular weight distribution can be identified by size exclusion chromatography.

Examples of the catalyst used for the polymerization of the ethynyl group include a transition metal catalyst containing a complex. Examples of the catalyst include molybdenum-containing compounds such as hexacarbonyl molybdenum, tungsten-containing compounds such as hexacarbonyl tungsten or hexachlorotungene / tetraphenyltin, tetrabutoxytitanium, tetrachlorotitanium, hexachlorotitanium or tetrabutoxytitanium / triethyl. Titanium-containing compounds such as aluminum, 2,5-norbornadiene-p-toluenesulfonate rhodium, 1,5-cyclopentadiene-p-toluenesulfonate rhodium, rhodium norbornadiene halides such as _{[Rh (norbornadiene) Cl] 2, [Rh} (Cyclooctadien) Cl] _{Rhodium cyclooctadiene halide such as 2} , [Rh (bis-cyclooctadien) Cl] _2, (nbd) Rh ⁺ B ^- Ph _{4 and} other rhodium-containing compounds, palladium acetate, bis (Tetra-n-butylammonium) bis (1,3-dithiol-2-thione-4,5-dithiolate) palladium (II), bis (triphenylphosphine) palladium (II) dichloride, bis (bensonitrile) palladium (II) ) Rhodium, bis (acetamite) palladium (II) dichloride, [1,2-bis (diphenylphosphino) ethane] palladium (II) dichloride, bis (2,4-pentandionate) palladium (II) or bis (tri) Examples thereof include compounds containing palladium such as phenylphosphine) palladium (II) diacetate. The transition metal catalyst is preferably hexacarbonyl molybdenum hexacarbonyl, [Rh (norbornadiene) Cl] ₂ , (nbd) Rh ⁺ B ^- Ph ₄ , bis (triphenylphosphine) palladium (II) dichloride and the like. The polyacetylene compound has two isomers having a cis-type and a trans-type acetylene chain, and a polyacetylene compound having a desired structure can be obtained depending on the type of catalyst. Whether it is a cis type or a trans type can be identified by infrared spectroscopy (IR), Raman spectrum, or the like. For example, in the IR spectrum of the polyacetylene compound, a 740 cm ^-1 absorption peak of C-H out-of-plane bending vibration in cis, since the trans is 1014 cm ^-1, the C-H out-of-plane deformation vibration It is possible to identify whether it is a cis type, a trans type, or a mixture thereof by the absorption intensity. Further, in the Raman spectrum, the stretching vibration of the C-C double bond is located in cis or trans or a mixture thereof from being a 1450～1550Cm ^-1 in 1500～1600Cm ^-1, trans is cis Can be identified.

The amount of the catalyst used for the polymerization may be, for example, 0.00001 to 1 mol, preferably 0.005 to 0.5 mol, based on 1 mol of the compound of the formula (I).

The organic solvent used for polymerization is not limited, but for example, hydrocarbons (aliphatic hydrocarbons such as hexane and heptane, aromatic hydrocarbons such as benzene, toluene, xylene and cumene, cyclopentane, etc. Alicyclic hydrocarbons such as cyclohexane), halogenated hydrocarbons (chloroform, carbon tetrachloride, methylene chloride, dichloroethane, trichloroethane, etc.), alcohols (methanol, ethanol, isopropanol, ethylene glycol, propylene glycol, etc.), nitrogen compounds (Acethane, nitromethane, nitroethane, nitrobenzene, triethylamine, acetamide, dimethylformamide, etc.), ether (diethyl ether, dioxane, tetrahydrofuran, cellosolve, etc.), ketones (acetone, methylethylketone, etc.), fatty acids (acetic acid, anhydrous acetic acid, etc.), dimethylsulfoxide Such as organic sulfoxides and sulfones, esters (ethyl acetate, ethyl lactate, etc.), etc., or combinations thereof. Preferably, it is triethylamine, chloroform, methylene chloride or a combination thereof. Further, among the above organic solvents, triethylamine can be used as a co-catalyst. _{When rhodium norbornadiene halide such as [Rh (norbornadiene) Cl] 2} is selected as the catalyst, the amount of triethylamine added is, for example, 0.1 to 100 mol, preferably 0.1 to 100 mol, per 1 mol of the catalyst. Between 50 moles.

<Thermosetting product>
According to another embodiment of the present invention, a thermosetting product of a composition containing a polyacetylene compound is also provided. In the present invention, the polyacetylene compound obtained by polymerizing the ethynyl group of the acetylene-containing benzoxazine compound represented by the above formula (I) is subjected to ring-opening polymerization of the benzoxazine ring to provide heat having excellent heat resistance. A cured product can be obtained. That is, the composition containing the above-mentioned polyacetylene compound can be used as a thermosetting composition. The presence or absence of ring-opening polymerization can be confirmed by the presence or absence of a specific characteristic absorption peak by IR measurement.

A thermosetting cured product (cured resin) of the polyacetylene compound represented by the above formula (II) can be produced as follows. That is, ring-opening polymerization can be performed and cured under the same curing conditions as known benzoxazine compounds. For example, the compound of formula (II) is heated at, for example, 150 to 350 ° C., preferably 180 to 300 ° C., for example, for 30 minutes to 10 hours, preferably for 1 to 5 hours to obtain a cured product. Obtainable. At that time, it may be carried out in a state of being replaced with nitrogen, argon or the like. Further, if necessary, an initiator may be used, and examples of the initiator include phenol compounds, Lewis acids, sulfonic acids, cation generators, amine compounds, and the like, for example, 100 to 350 ° C., preferably 150. A cured product can be obtained by heating at ~ 300 ° C. for, for example, 30 minutes to 10 hours, preferably 1 to 5 hours. The obtained cured product is a polymer having an N, O-acetal structure in the main chain and / or a Mannich-type polymer.

The thermosetting product obtained as described above is a ring-opening polymerization of benzoxazine, but since a crosslinked structure is formed by polyacetylene chains bonded to the benzene ring, it has thermal conductivity in addition to heat resistance. An excellent cured product can be realized. Compared with the conventional benzoxazine resin crosslinked by the polyacetylene chain, the cured product according to the present invention has the polyacetylene chain bonded to the benzene ring instead of the oxazine ring of benzoxazine, so that the cured product is thermally decomposed. It is expected that the crosslink density will not decrease with the desorption of the aniline compound, and the heat resistance will be further improved. Therefore, it can be suitably used in various fields such as adhesives, encapsulants (for example, encapsulants used in the electronic field), laminated boards, paints, matrix resins for composite materials, and the like.

Hereinafter, the present invention will be specifically described with reference to examples. The production method is an example, and the acetylene-containing benzoxazine compound according to the present invention is not limited to the following production method.

The following devices were used to identify the compounds of each example, and the following methods were used.
・ IR; FT / IR-4100 FT-IR Spectrometer (manufactured by JASCO Corporation)
A 2 mg sample was blended with 20 mg of KBr (for IR absorption measurement) using a mortar, and the mixed powder was applied to a press to prepare a film, and then the measurement was performed.
・^{1 1} HNMR, ¹³ CNMR; JNM-ECS Series FT NMR equipment (JEOL RESONANCE Ltd., manufactured by JEOL Ltd.)
・ Mass spectrum; DART mass spectrometer (ionizer DART-SVP (manufactured by AMR Co., Ltd.) and multi-mass spectrometry system LC-IT-TOF (manufactured by Shimadzu Corporation))
As a measurement sample, a solution obtained by dissolving 2 mg of the sample in 1 mL of methanol and then diluting it 10 times was measured.
・ Raman spectrum; 3D microlaser Raman spectrometer Nanofiber30 (manufactured by Tokyo Instruments)
The measurement was performed at a laser wavelength of 748 nm and a laser intensity of 50 mW.

(Example 1)
Synthesis of Monomer (3,4-Dihydro-6-Ethynyl-2H-3-phenyl-1,3-benzoxazine) (1) Synthesis of 4- [2- (trimethylsilyl) ethynyl] benzene (4- [2- (trimethylsilyl) ethynyl] benzene) (Compound 1) Compound 1 was obtained as in Scheme I shown below. That is, p-iodophenyl (9.90 g, 45.0 mmol), copper (I) iodide (CuI (I)) (0.358 g, 1.8 mmol), bis (triphenylphosphen) palladium (II) dichloride. After replacing the flask containing (PdCl ₂ (PPh ₃ ) ₂ ) (0.640 g, 0.90 mmol) with degassed argon (Ar), tetrahydrofuran (THF) (112.5 mL) and triethylamine (Et ₃ N) ( 7.5 mL) was added and the mixture was stirred for 20 minutes. Then, trimethylsilylacetylene (TMSA) (6.35 mL, 45.0 mmol) was added, and the mixture was stirred (refluxed) for 21 hours under shading.
After completion of the reaction, the solvent was distilled off, diethyl ether was added to the residue, and the obtained organic layer was washed with pure water and dried over anhydrous magnesium sulfate. After removing anhydrous magnesium sulfate by filtration, the solvent was distilled off to obtain a brown viscous residue.
The obtained residue was dissolved in benzene (20 mL), heated to 60 ° C., ethylenediamine (4 mL) was added, and the mixture was stirred for 20 minutes. The precipitate was filtered off, and the removed filtrate was washed with a 0.5 M aqueous hydrochloric acid solution and dried over anhydrous magnesium sulfate. After separating anhydrous magnesium sulfate, the solvent was distilled off, and the residue was purified by silica gel column chromatography (eluent: ethylacetone / hexane = 1/4) to obtain Compound 1 (3.47 g, yield: 1/4) as a brown solid. 40.5%) was obtained. Compound 1 was identified by ^{1 1} H-NMR spectrum. The ¹ H-NMR spectrum was measured after dissolving Compound 1 in deuterated chloroform containing no tetramethylsilane (TMS).
The result of NMR measurement is shown in FIG.

(2) 3,4-Dihydro-2H-3-phenyl-6- [2- (trimethylsilyl) ethynyl] -1,3-benzoxazine (3,4-Dihydro-2H-3-phenyl-6- [2-] Synthesis of (trimethylsilyl) toluene] -1,3-benzoxazine (Compound 2) Compound 2 was obtained as in Scheme II shown below. That is, compound 1 obtained as described above was placed in a 100 mL eggplant flask. (1.90 g, 10 mmol), 1,3,5-trioxazine (0.595 g, 6.6 mmol), aniline (0.91 mL, 10 mmol) and toluene (30 mL) were charged and stirred at 90 ° C. for 5 hours.
After completion of the reaction, the solvent was distilled off, diethyl ether was added to the residue, the obtained organic layer was ^{washed with a 1.5 × 10 -3} M aqueous sodium hydroxide solution, and the organic layer was dried over anhydrous magnesium sulfate. After separating anhydrous magnesium sulfate, the solvent was distilled off to obtain Compound 2 (2.17 g, yield: 70%) as a brown solid.
Compound 2 was identified by ^{1 1} H-NMR spectrum and ¹³ C-NMR spectrum. Both ¹ H-NMR spectrum and ¹³ C-NMR spectrum were measured after compound 2 was dissolved in deuterated chloroform.
The results of the NMR measurement are shown in FIGS.

(3) 3,4-Dihydro-6-ethynyl-2H-3-phenyl-1,3-benzoxazine (3,4-Dihydro-6-ethynyl-2H-3-phenyl-1,3-benzoxazine) (Compound Synthesis of 3) Compound 3 was obtained as in Scheme III shown below. That is, the compound 2 (0.40 g, 1.3 mmol) obtained as described above was dissolved in tetrahydrofuran (THF) (5 mL), and a tetrabutylammonium fluoride (TBAF) 1 mol / L THF solution (15.6 ml) was dissolved. , TBAF 15.6 mmol) and stirred at room temperature for 1 hour.
After completion of the reaction, diethyl ether was added, the mixture was washed with pure water, and the organic layer was dried over anhydrous magnesium sulfate. After separating anhydrous magnesium sulfate, the solvent was distilled off with an evaporator to obtain a tan viscous liquid.
The obtained yellowish brown viscous liquid was purified by silica gel column chromatography (eluent: chloroform) to obtain Compound 3 (0.20 g, yield: 65%) as a yellowish white solid.

Compound 3 was identified by ^{1 1} H-NMR spectrum, ¹³ C-NMR spectrum, IR spectrum and mass spectrum. Both ¹ H-NMR spectrum and ¹³ C-NMR spectrum were measured after dissolving Compound 3 in deuterated chloroform.
The results of NMR measurement are shown in FIGS. 4 and 5, the results of IR spectrum are shown in FIG. 6 and below, and the results of mass spectrum are shown below.

[Mass spectrum]
[M] ^{+ ・}235, [M + H] ⁺ 236,
[IR spectrum]
3269, 2918, 2101 (C≡C), 1599, 1493, 1232, 939, 758cm ^-1

(Example 2)
Polyacetylene synthesized Schlenk tube [Rh _{(norbornadiene) Cl] 2 ([(nbd} ) RhCl] 2) (1.68mg, 0.364 × 10 -2 mmol) placed and deaerated argon, chloroform (CHCl ₃ ) (2.28 mL) was added and stirred for 5 minutes. Then, Et ₃ N (0.005 mL) was added, heated to 30 ° C., and a solution of Compound 3 (85.7 mg, 0.364 mmol) dissolved in chloroform (5.00 mL) was added. After stirring for 1 hour, a blackish brown liquid was obtained.
Polymerization conditions: [Compound 3] ₀ = 50 mM, [Compound 3] ₀ / [Rh] = 100, [Et ₃ N] / [Rh] = 10. (Note that [Compound 3] ₀ indicates the molar concentration of Compound 3 in the reaction solution at the start of the reaction. [Compound 3] ₀ / [Rh] and [Et ₃ N] / [Rh] are reactions, respectively. starting [(nbd) _RhCl] molar ratio of compound 3 with respect to _2, at the start of the reaction [(nbd) _RhCl] a molar ratio of Et ₃ N for _2.)
The obtained polymerization mixture was put into methanol, and the precipitated solid was filtered off to obtain a brown solid polyacetylene compound (45.0 mg, yield: 52.5%). The results of size exclusion chromatography measurement (eluent: THF, polystyrene conversion) of the polyacetylene compound are shown in FIG. As a result, it was confirmed that _{M n} = 7,900, M _w = 22,100, and M _w / M _{n = 2.7.} Moreover, the measurement result of the Raman spectrum of the polyacetylene compound is shown in FIG. As a result, a peak of ^{1550 cm -1 attributed to polyacetylene was confirmed.}

(Example 3)
A chloroform solution of the obtained polyacetylene compound was spin-coated on a glass plate (1040 rpm, 1 minute) to prepare a film. After drying, the curing reaction was carried out by heating under nitrogen at 250 ° C. for 2 hours. The IR spectra of the polyacetylene compound before and after heating are shown in FIG. From the IR spectra before and after heating, ^{the residual peak of cis-type polyacetylene (740 cm -1} ) was confirmed. In addition, ring-opening polymerization of the benzoxazine ring proceeded in the cured product after heating, and disappearance of the ^{peak (1220, 930 cm -1) attributed to benzoxazine was confirmed.} Further, FIG. 8 shows the measurement result of the Raman spectrum of the cured product after heating. As a result, it was confirmed that a peak of ^{1550 cm -1 attributed to polyacetylene remained.}

Claims (5)

Acetylene-containing benzoxazine compound represented by the following formula (I):

[In formula (I),
R ¹ represents hydrogen, an optionally substituted alkyl group, or an optionally substituted aryl group.
R ² represents an optionally substituted alkyl group or optionally substituted aryl group. ]. The acetylene-containing benzoxazine compound according to claim 1, wherein ^{R 1} is hydrogen in the formula (I). The acetylene-containing benzoxazine compound according to claim 1 or 2, ^{wherein R 2} is a phenyl group in the formula (I). A polyacetylene compound obtained by polymerizing the ethynyl group of the acetylene-containing benzoxazine compound according to any one of claims 1 to 3. A thermosetting product of a composition containing the polyacetylene compound according to claim 4.

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