JP7079863B2 - New benzoxazine compound - Google Patents

Description

The present invention relates to novel benzoxazine compounds. More specifically, the present invention relates to a benzoxazine compound which has a bis (oxyphenyl) skeleton in the center and has an unsubstituted benzoxazine ring bonded to both ends thereof via an m-phenylene group.

The benzoxazine compound is known as a thermosetting resin raw material having excellent heat resistance and flame retardancy because the benzoxazine ring is ring-opened and cured by ring-opening polymerization without producing volatile by-products by heating. Has been done.
Conventionally, several compounds are known as such benzoxazine compounds, and as a compound having particularly excellent heat resistance and flame retardancy, for example, benzoxazine at both ends of a diphenylmethane-4,4'-diyl group. A benzoxazine compound having a ring (Patent Document 1), a compound having a benzoxazine ring substituted with a hydroxyalkyl group at both ends of a di (phenoxyphenyl) sulfone (Patent Document 2), both ends of a di (phenoxyphenyl) sulfone. Some benzoxazine compounds having an aromatic ring in the central skeleton, such as a compound having a benzoxazine ring substituted with an alkyl group or the like (Patent Document 3), are also known.
However, the resins obtained from these benzoxazine compounds still do not have sufficient physical properties such as heat resistance, and further improvement of the benzoxazine compounds is required.

Japanese Unexamined Patent Publication No. 2004-352670 Japanese Unexamined Patent Publication No. 2011-11415 Japanese Patent Publication No. 2014-503669

An object of the present invention is to provide a benzoxazine compound having improved performance such as heat resistance when used as a resin raw material.

As a result of diligent studies to solve the above-mentioned problems, the present inventor has a bis (oxyphenyl) skeleton in the center and does not replace the chemical structure of the benzoxazine compound via an m-phenylene group at both ends thereof. The present invention has been completed by finding that a resin having excellent heat resistance can be obtained by using a compound to which the benzoxazine ring of the above is bonded.

（式中、Ｘはスルホニル基を示す。） The present invention is as follows.
1. 1. A benzoxazine compound represented by the general formula (1).

(In the formula, X represents a sulfonyl group.)

INDUSTRIAL APPLICABILITY The present invention provides a novel benzoxazine compound having a bis (oxyphenyl) skeleton in the center and having an unsubstituted benzoxazine ring bonded to both ends thereof via an m-phenylene group. Compared with the conventionally known benzoxazine compounds, this novel benzoxazine compound is excellent in heat resistance, flame retardancy, etc. when used as a resin raw material. Therefore, it is suitable as a resin raw material for varnishes that can be applied to various substrates, prepregs impregnated with varnishes, printed circuit boards, encapsulants for electronic parts, electric / electronic molded parts, automobile parts, laminated materials, paints, resist inks, etc. Can be used for.

（式中、Ｘはスルホニル基を示す。）
前記一般式（１）において、式中Ｘがスルホニル基である化合物（以下、「化合物１」という。）の化学構造を下記に示す。

The benzoxazine compound of the present invention is represented by the following general formula (1).

(In the formula, X represents a sulfonyl group.)
In the general formula (1), the chemical structure of the compound in which X is a sulfonyl group (hereinafter referred to as “compound 1”) is shown below.

The method for producing the benzoxazine compound represented by the general formula (1) of the present invention is not particularly limited with respect to the starting material and the production method in the production thereof, and are described in, for example, JP-A-2006-335671. In addition, a known method for producing a benzoxazine compound, such as stirring and mixing a primary amine compound, a phenol compound and formalin in the presence of a solvent, and causing a dehydration condensation reaction under heating, can be arbitrarily adopted. .. However, preferably, a diamine compound represented by the general formula (2) described later is used as a starting material, and this is subjected to a dehydration condensation reaction with 2-hydroxybenzaldehyde to obtain a diimine compound (1).
Step (2) of hydrogenating the diamine compound to obtain a secondary diamine compound.
Step of dehydrating and condensing the secondary diamine compound with formaldehyde to cyclize it into a benzoxazine compound (3)
A production method containing sequentially is preferable.
In the above three reaction steps, each reaction step may be performed separately or continuously. For example, after the target product is isolated or purified from the reaction-terminated mixture containing the target product of the step obtained in the reaction, the target product may be used as a raw material for the next step and the reaction of the next step may be sequentially carried out. The reaction of the next step may be sequentially carried out by using the reaction-terminated mixture containing the target substance of the step as it is as a raw material of the next step.

工程（２）

工程（３）

Hereinafter, each step is exemplified by a reaction formula for the manufacturing methods of steps (1) to (3).
Process (1)

Process (2)

Process (3)

（式中、Ｘはスルホニル基を示す。）
一般式（２）中の「Ｘ」がスルホニル基である化合物（以下、「化合物１Ａ」という。）の化学構造を下記に示す。

第一級ジアミンと２－ヒドロキシベンズアルデヒドとの脱水縮合反応において、原料の第一級ジアミンと２－ヒドロキシベンズアルデヒドとの添加モル比（２－ヒドロキシベンズアルデヒド／第一級ジアミン）は、少なくとも化学量論比以上であり、好ましくは、２／１～３／１の範囲である。 The production method including the steps (1) to (3), which is a preferable production method of the benzoxazine compound represented by the above general formula (1) of the present invention, will be described in more detail.
<About process (1)>
The step (1) is a step of dehydrating and condensing the primary diamine compound with 2-hydroxybenzaldehyde to obtain a diimine compound. The raw material primary diamine compound is a diamine compound represented by the following general formula (2) corresponding to the benzoxazine compound of the present invention.

(In the formula, X represents a sulfonyl group.)
The chemical structure of the compound in which "X" in the general formula (2) is a sulfonyl group (hereinafter referred to as "Compound 1A") is shown below.

In the dehydration condensation reaction between the primary diamine and 2-hydroxybenzaldehyde, the added molar ratio (2-hydroxybenzaldehyde / primary diamine) of the raw material primary diamine and 2-hydroxybenzaldehyde is at least the chemical quantitative ratio. The above is preferably in the range of 2/1 to 3/1.

The reaction is usually carried out in the presence of a solvent. The solvent is not particularly limited as long as it does not inhibit the reaction, but is an aliphatic ester solvent such as acetate, an aliphatic ether solvent such as 1,4-dioxane and tetrahydrofuran, an alcohol solvent such as 2-methoxyethanol and the like. Is preferably mentioned. These solvents can be used alone or in combination. The amount of the solvent used is not particularly limited as long as it does not interfere with the reaction, but is usually used in the range of 5 to 10 times by weight with respect to the raw material primary diamine.
The reaction temperature is usually in the range of room temperature to 120 ° C. The reaction pressure may be carried out under normal pressure conditions, under pressure or under reduced pressure.
No particular catalyst is required to accelerate the reaction.
There are no restrictions on the method of adding raw materials, solvents, etc., the reaction method, and the like, and the reaction can be appropriately selected. For example, 2-hydroxybenzaldehyde (salitylaldehyde) is added dropwise to a mixed solution of a primary diamine and a solvent at a predetermined temperature under stirring, and then the reaction is carried out at that temperature, or after the addition is completed. Examples thereof include a method in which the temperature is further raised and water produced as a by-product is azeotropically boiled with a solvent to distill out of the system while reacting.
After the reaction is completed, if the crystals or solids of the target product are precipitated or precipitated, the reaction-terminated mixture containing the target product in the step (1) thus obtained can be used as it is or cooled to prepare the reaction solution. The desired product of the step can be obtained by filtering and drying the obtained crystals. Further, if the crystals or solid of the target product are not precipitated or precipitated at the end of the reaction, the target product can be taken out from the reaction end mixture according to a known method. For example, the target product can be precipitated and precipitated by dropping the reaction-terminated mixture into a large amount of the poor solvent or adding the poor solvent to the reaction-terminated mixture. The desired product of the obtained step (1) can be recrystallized as necessary to increase its purity. Further, the obtained isolated product of the target product of the step (1) or the reaction-terminated mixture containing the target product is used as a raw material of the step (2). Here, it is preferable to use the isolated product of the step (1) as the raw material of the step (2).

The chemical structure of the compound obtained from "Compound 1A" (hereinafter referred to as "Compound 1B") in the step (1) is shown below.

<About process (2)>
The step (2) is a step of hydrogenating the diimine compound obtained in the step (1) to obtain a secondary diamine compound.
The hydrogenation reaction of the diimine compound is preferably a reduction reaction with a reducing agent, and the reducing agent is a known aluminum hydride system in which imine described in, for example, JP-A-2002-255908 is hydrogenated to form a secondary amine. , Boron hydride type, silicon hydride type and other reducing agents can be used. A boron hydride system is preferable, and sodium borohydride and lithium borohydride are particularly preferable. The amount of the reducing agent used is usually preferably 2 to 4 mol times as much as 1 mol of the raw material diimine.
The reduction reaction is usually carried out in the presence of an alcohol solvent. Preferred alcohol solvents are lower alcohols such as methanol, ethanol and isopropanol. These solvents can be used alone or in combination. Further, the amount of the solvent used is not particularly limited, but is usually preferably in the range of 5 to 20 times by weight with respect to the raw material diimine.
The reaction temperature is preferably in the range of room temperature to 50 ° C.
There are no restrictions on the mode of the reaction, the method of adding the raw material, the reducing agent, the solvent, etc., the reaction method, and the like, and the reaction can be appropriately selected. For example, a method in which the raw material diimine, the reducing agent and the solvent are put together in a reaction vessel and then stirred, or the raw material diimine and the solvent are put in a reaction vessel and then the reducing agent is divided and added under stirring. Can be mentioned.

After the reaction is completed, if the crystals or solids of the target product are precipitated or precipitated, the reaction-terminated mixture containing the target product in the step (2) thus obtained can be used as it is or cooled to prepare the reaction solution. The desired product of the step can be obtained by filtering and drying the obtained crystals. Further, if the crystals or solid of the target product are not precipitated or precipitated at the end of the reaction, the target product can be taken out from the reaction end mixture according to a known method. For example, the target substance can be precipitated and precipitated by dropping the reaction-terminated mixture into a large amount of the poor solvent or adding the poor solvent to the reaction-terminated mixture.
The object of the obtained step (2) can be recrystallized or washed with water as needed to increase its purity. The obtained isolated product of the target product in step (2) or the reaction-terminated mixture containing the target product is used as a raw material for step (3). Here, it is preferable to use the isolated product of the step (2) as the raw material of the step (3).

The chemical structure of the compound obtained from "Compound 1B" (hereinafter referred to as "Compound 1C") in the step (2) is shown below.

<About process (3)>
The step (3) is a step of cyclizing the secondary diamine compound obtained in the step (2) by dehydration condensation reaction with formaldehyde to obtain a benzoxazine compound.
Examples of the raw formaldehyde used in the reaction include formalin (aqueous formaldehyde solution) and paraformaldehyde. The added molar ratio (formaldehyde / secondary diamine) of the raw material secondary diamine to formaldehyde is at least the stoichiometric ratio or more, and is preferably in the range of 2/1 to 3/1.
The reaction is usually carried out in the presence of a solvent. The solvent is not particularly limited as long as it does not inhibit the reaction, but is preferably an alcohol solvent such as ethanol, n-propanol and 2-methoxyethanol, an aliphatic ester solvent such as ethyl acetate and butyl acetate, and diethyl ether. Examples thereof include an aliphatic ether solvent such as dioxane.
The reaction temperature is preferably in the range of 40 to 120 ° C.
No particular catalyst is required to accelerate the reaction.
There are no restrictions on the method of adding raw materials, solvents, etc., the reaction method, and the like, and the reaction can be appropriately selected. For example, a method in which an aqueous formaldehyde solution is added dropwise to a mixed solution of a secondary diamine as a raw material and a solvent at a predetermined temperature at a predetermined temperature, and then the reaction is carried out at that temperature, or after the addition of the aqueous formaldehyde solution is completed, further. Examples thereof include a method in which the reaction is carried out under reflux conditions while azeotropically boiling water produced as a by-product by raising the temperature with a solvent and distilling it out of the system.

After the reaction is completed, the reaction-terminated mixture containing the benzoxazine compound of the present invention obtained in the step (3) thus obtained is cooled as it is or cooled if crystals or solids of the target substance are precipitated or precipitated. The reaction solution is filtered, and the obtained crystals are dried to obtain the target product of the step. Further, if the crystals or solid of the target product are not precipitated or precipitated at the end of the reaction, the target product can be taken out from the reaction end mixture according to a known method. For example, the target product can be precipitated and precipitated by dropping the reaction-terminated mixture into a large amount of the poor solvent or adding the poor solvent to the reaction-terminated mixture.
The obtained target product of the step can be recrystallized or washed with water according to a known method to obtain a high-purity product, if necessary.
Thus, in step (3), "Compound 1" can be obtained from "Compound 1C".

The obtained benzoxazine compound is subjected to ring-opening polymerization by heating to produce a benzoxazine resin. Although a curing agent is basically not required for curing the benzoxazine compound, a high temperature of about 180 ° C. to 200 ° C. is usually required for curing. Known curing accelerators such as organic acids and phenols can also be used to lower the curing temperature.

工程（２）：第二級ジアミン化合物「化合物１Ｃ」の合成
３リッター四つ口フラスコに工程（１）で得られたジイミン化合物「化合物１Ｂ」１４７ｇ、エタノール１４８７ｇを仕込み、水素化ホウ素ナトリウム２６．２ｇの粉末を２時間毎に３回に分けて室温で添加した。添加後、室温で２２時間撹拌すると僅かに濁りのある黄色透明の溶液となった。この溶液を水１７６９ｇとエタノール２８２ｇとの混合液に滴下し生成した沈殿をろ別した。この沈殿を２４６３ｇの水に分散させ室温で３時間撹拌して、ろ別し、さらに１５３１ｇの水に分散し室温で３時間撹拌した後ろ別し、漏斗の上からろ液のｐＨが７になるまで水を掛けて洗浄した。
得られた粉体を乾燥して、純度９３．７％（高速液体クロマトグラフィー分析法）の第二級ジアミン化合物「化合物１Ｃ」の粉末１２８ｇを得た。
収率 ８６．１％（ジイミン化合物「化合物１Ｂ」に対する収率）
１Ｈ‐ＮＭＲ（４００ＭＨｚ）測定（溶媒：DMSO-d6）：4.15(s, 2H×2:a), 6.21(ddd, 1H×2:b), 6.26(dd, 1H×2:c), 6.30(s, 1H×2:d), 6.48(ddd, 1H×2:e), 6.71(ddd, 1H×2:f), 6.78(dd, 1H×2:g), 7.02-7.13(m, 5H×2:h,i,j,k), 7.86(ddd, 2H×2:l).

工程（３）：ベンゾオキサジン化合物「化合物１」の合成
１リッター四つ口フラスコに工程（２）で合成した第二級ジアミン化合物「化合物１Ｃ」３６ｇ、酢酸エチル４８０ｇを仕込み、３５％ホルマリン水溶液１２ｇを４０℃で滴下した。滴下終了後４０℃で１６．５時間撹拌すると、撹拌中に結晶が析出した。反応終了液を室温まで冷却した後、結晶をろ別し乾燥することにより、純度１００％（ゲルパーミエーションクロマトグラフィー分析法）のベンゾオキサジン化合物「化合物１」の結晶３１．５ｇを得た。
収率 ８４．４％（第二級ジアミン化合物「化合物１Ｃ」に対する収率）
融点 １３９℃（示差走査熱量測定法）
１Ｈ‐ＮＭＲ（４００ＭＨｚ）測定（溶媒：CDCl3）：4.61(s, 2H×2:a), 5.32(s, 2H×2:b), 6.55(ddd, 1H×2:c), 6.77(dd, 1H×2:d), 6.80(dd, 1H×2:e), 6.87(ddd, 1H×2:f), 6.94(ddd, 1H×2:g), 6.98-7.01(m, 3H×2:h,i), 7.12(ddd, 1H×2:j), 7.26(t, 1H×2:k), 7.84(ddd, 2H×2:l).

重合：ベンゾオキサジン化合物「化合物１」の重合
得られたベンゾオキサジン化合物「化合物１」を１７０℃で融解させ、オーブン中１８０℃で２時間、２００℃で２時間硬化させた硬化物のガラス転移温度は、動的粘弾性測定のtanδ値で２３５℃であった。 Hereinafter, the present invention will be described in more detail with reference to Examples.
<Example 1> (Synthesis of benzoxazine compound "Compound 1" and polymerization of the compound)
Step (1): Synthesis of diimine compound "Compound 1B" 180 g of the primary diamine compound "Compound 1A" and 900 g of ethyl acetate were placed in a 2-liter four-necked flask, and 112 g of salicylaldehyde was added dropwise at room temperature. After the dropping, the mixture was stirred under reflux with ethyl acetate for 21 hours, and as a result, crystals were precipitated during stirring. The reaction completion solution was cooled to 4 ° C., filtered, and the separated crystals were dried to obtain 234 g of crystals of the diimine compound "Compound 1B" having a purity of 99.7% (gel permeation chromatography analysis method).
Yield 87.0% (yield with respect to "Compound 1A")
Melting point 164 ° C (differential scanning calorimetry)
1H-NMR (400MHz) measurement (solvent: CDCL3): 6.93-7.14 (m, 7H × 2: b, c, e, f, g, i), 7.37-7.41 (m, 3H × 2: d, h, j), 7.91 (d, 2H × 2: a), 8.60 (s, 1H × 2: l), 12.94 (s, 1H × 2: k).

Step (2): Synthesis of the secondary diamine compound "Compound 1C" 147 g of the diimine compound "Compound 1B" and 1487 g of ethanol obtained in the step (1) were charged in a 3-liter four-necked flask, and sodium borohydride 26. 2 g of powder was added every 2 hours in 3 divided doses at room temperature. After the addition, the mixture was stirred at room temperature for 22 hours to obtain a slightly turbid yellow transparent solution. This solution was added dropwise to a mixed solution of 1769 g of water and 282 g of ethanol, and the resulting precipitate was filtered off. This precipitate was dispersed in 2463 g of water, stirred at room temperature for 3 hours and filtered, and further dispersed in 1531 g of water and stirred at room temperature for 3 hours. Washed with water.
The obtained powder was dried to obtain 128 g of a secondary diamine compound "Compound 1C" having a purity of 93.7% (high performance liquid chromatography analysis method).
Yield 86.1% (Yield with respect to dimin compound "Compound 1B")
1H-NMR (400MHz) measurement (solvent: DMSO-d6): 4.15 (s, 2H × 2: a), 6.21 (ddd, 1H × 2: b), 6.26 (dd, 1H × 2: c), 6.30 ( s, 1H × 2: d), 6.48 (ddd, 1H × 2: e), 6.71 (ddd, 1H × 2: f), 6.78 (dd, 1H × 2: g), 7.02-7.13 (m, 5H ×) 2: h, i, j, k), 7.86 (ddd, 2H × 2: l).

Step (3): Synthesis of benzoxazine compound "Compound 1" 36 g of the secondary diamine compound "Compound 1C" synthesized in step (2) and 480 g of ethyl acetate were placed in a 1-liter four-necked flask, and 12 g of a 35% formalin aqueous solution was charged. Was added dropwise at 40 ° C. After the completion of the dropping, the mixture was stirred at 40 ° C. for 16.5 hours, and crystals were precipitated during the stirring. After cooling the reaction completion solution to room temperature, the crystals were separated by filtration and dried to obtain 31.5 g of crystals of the benzoxazine compound "Compound 1" having a purity of 100% (gel permeation chromatography analysis method).
Yield 84.4% (Yield with respect to the secondary diamine compound "Compound 1C")
Melting point 139 ° C (differential scanning calorimetry)
1H-NMR (400MHz) measurement (solvent: CDCl3): 4.61 (s, 2H × 2: a), 5.32 (s, 2H × 2: b), 6.55 (ddd, 1H × 2: c), 6.77 (dd, 1H × 2: d), 6.80 (dd, 1H × 2: e), 6.87 (ddd, 1H × 2: f), 6.94 (ddd, 1H × 2: g), 6.98-7.01 (m, 3H × 2: h, i), 7.12 (ddd, 1H × 2: j), 7.26 (t, 1H × 2: k), 7.84 (ddd, 2H × 2: l).

Polymerization: Polymerization of the benzoxazine compound "Compound 1" The glass transition temperature of the cured product obtained by melting the obtained benzoxazine compound "Compound 1" at 170 ° C and curing it in an oven at 180 ° C for 2 hours and at 200 ° C for 2 hours. Was 235 ° C. in the tan δ value of the dynamic viscoelasticity measurement.

工程（１）：ジイミン化合物＜ビス｛４－{４－[２－(２－ヒドロキシフェニル)－１－アザビニル]フェノキシ}フェニル｝スルホン＞の合成
ビス｛４－（４－アミノフェニルオキシ）フェニル｝スルホン４００ｇ、１，４－ジオキサン２０００ｇを５リッター四つ口フラスコに仕込み、６０℃でサリチルアルデヒド２４９ｇを滴下した。滴下後６０℃で２２時間撹拌したが、撹拌中に結晶が析出した。反応終了液を１５℃まで冷却後、ろ過、乾燥して、純度１００％（ゲルパーミエーションクロマトグラフィー分析法）のビス｛４－{４－[２－(２－ヒドロキシフェニル)－１－アザビニル]フェノキシ}フェニル｝スルホンの結晶５７５ｇを得た。
収率 ９７．０％（原料第一級ジアミン対する収率）
融点 ２０９℃（示差走査熱量測定法）
１Ｈ‐ＮＭＲ（４００ＭＨｚ）測定（溶媒：CDCl3）：6.96(t, 1H×2:g), 7.03-7.07(m, 3H×2:b,e), 7.10(d, 2H×2:d), 7.30(d, 2H×2:c), 7.38-7.42(m, 2H×2: h,f), 7.90(d, 2H×2:a), 8.63(s, 1H×2:i), 13.10(s, 1H×2:j).

工程（２）：第二級ジアミン化合物＜ビス｛４－(４－{[(２－ヒドロキシフェニル)メチル]アミノ}フェノキシ)フェニル｝スルホン＞の合成
５リッター四つ口フラスコに工程（１）で得られたビス｛４－{４－[２－(２－ヒドロキシフェニル)－１－アザビニル]フェノキシ}フェニル｝スルホン３００ｇ、エタノール３０００ｇを仕込み、水素化ホウ素ナトリウム５３．３ｇの粉末を２時間毎に３回に分けて室温で添加した。添加後室温で２７時間撹拌した後、水素化ホウ素ナトリウムの粉末を１７．８ｇ追加した。追加後、室温で２３時間撹拌するとクリーム色のスラリー液となった。この液を５℃まで冷却し、析出物をろ別した後、この析出物を２１８６ｇの水に分散させ室温で３時間撹拌し、ろ別した。さらに１４４０ｇの水に分散し室温で１．５時間撹拌した後、ろ別し、漏斗の上からろ液のｐＨが８になるまで水を掛けて洗浄した。得られた析出物を乾燥して、純度９１．４％（高速液体クロマトグラフィー分析法）のビス｛４－(４－{[(２－ヒドロキシフェニル)メチル]アミノ}フェノキシ)フェニル｝スルホンの粉末２４２ｇを得た。
収率 ８０．１％（ビス｛４－{４－[２－(２－ヒドロキシフェニル)－１－アザビニル]フェノキシ}フェニル｝スルホンに対する収率）
融点 １４３℃（示差走査熱量測定法）
工程（３）：ベンゾオキサジン化合物「比較化合物」の合成
５リッター四つ口フラスコに工程（２）で合成したビス｛４－(４－{[(２－ヒドロキシフェニル)メチル]アミノ}フェノキシ)フェニル｝スルホン２４４ｇ、１，４－ジオキサン１２２２ｇを仕込み、３５％ホルマリン水溶液８１ｇを４０℃で滴下した。滴下終了後４０℃で３．５時間撹拌した。
この液を６８℃まで加熱し反応で析出した結晶を溶解した後、トルエン１２２１ｇを加え再度加熱した。この溶液を６６．５℃から５℃まで冷却後、析出した結晶をろ別、乾燥することにより、純度１００％（ゲルパーミエーションクロマトグラフィー分析法）のベンゾオキサジン化合物「比較化合物」の結晶１８４ｇを得た。
収率 ７２．６％：ビス｛４－(４－{[(２－ヒドロキシフェニル)メチル]アミノ}フェノキシ)フェニル｝スルホンに対する収率
融点 １８８℃（示差走査熱量測定法）
１Ｈ‐ＮＭＲ（４００ＭＨｚ）測定（溶媒：CDCl3）：4.62(s, 2H×2:a), 5.34(s, 2H×2:b), 6.82(dd, 1H×2:c), 6.91-6.94(m, 5H×2:d,e,f), 7.02(dd, 1H×2:g), 7.12-7.14(m, 3H×2:h,i), 7.80(ddd, 2H×2:j).

重合：ベンゾオキサジン化合物「比較化合物１」の重合
得られたベンゾオキサジン化合物「比較化合物１」を２００℃で融解させ、オーブン中２００℃で２時間硬化させた硬化物のガラス転移温度は、動的粘弾性測定のtanδ値で１９９℃であった。 <Comparative Example 1> Synthesis and polymerization of the benzoxazine compound "Comparative Compound 1" represented by the following chemical formula.

Step (1): Synthesis of diimine compound <bis {4- {4- [2- (2-hydroxyphenyl) -1-azavinyl] phenoxy} phenyl} sulfone> Bis {4- (4-aminophenyloxy) phenyl} 400 g of sulfone and 2000 g of 1,4-dioxane were charged into a 5-liter four-mouthed flask, and 249 g of salicylaldehyde was added dropwise at 60 ° C. After the dropping, the mixture was stirred at 60 ° C. for 22 hours, but crystals were precipitated during the stirring. The reaction completion solution is cooled to 15 ° C., filtered, dried, and subjected to 100% purity (gel permeation chromatography analysis method) bis {4- {4- [2- (2-hydroxyphenyl) -1-azavinyl]. 575 g of phenoxy} phenyl} sulfone crystals were obtained.
Yield 97.0% (yield with respect to the raw material primary diamine)
Melting point 209 ° C (differential scanning calorimetry)
1H-NMR (400MHz) measurement (solvent: CDCl3): 6.96 (t, 1H × 2: g), 7.03-7.07 (m, 3H × 2: b, e), 7.10 (d, 2H × 2: d), 7.30 (d, 2H × 2: c), 7.38-7.42 (m, 2H × 2: h, f), 7.90 (d, 2H × 2: a), 8.63 (s, 1H × 2: i), 13.10 ( s, 1H × 2: j).

Step (2): Synthesis of secondary diamine compound <bis {4- (4- {[(2-hydroxyphenyl) methyl] amino} phenoxy) phenyl} sulfone> in a 5-liter four-necked flask in step (1) 300 g of the obtained bis {4- {4- [2- (2-hydroxyphenyl) -1-azavinyl] phenoxy} phenyl} compound and 3000 g of ethanol were charged, and a powder of 53.3 g of boron hydride was added every 2 hours. It was added in 3 portions at room temperature. After the addition, the mixture was stirred at room temperature for 27 hours, and then 17.8 g of sodium borohydride powder was added. After the addition, the mixture was stirred at room temperature for 23 hours to obtain a cream-colored slurry liquid. The solution was cooled to 5 ° C., and the precipitate was filtered off. Then, the precipitate was dispersed in 2186 g of water, stirred at room temperature for 3 hours, and filtered off. Further, the mixture was dispersed in 1440 g of water, stirred at room temperature for 1.5 hours, filtered off, and washed with water from the top of the funnel until the pH of the filtrate became 8. The resulting precipitate was dried to a powder of bis {4- (4-{[(2-hydroxyphenyl) methyl] amino} phenoxy) phenyl} sulfone with a purity of 91.4% (high performance liquid chromatography analysis). 242 g was obtained.
Yield 80.1% (Yield for bis {4- {4- [2- (2-hydroxyphenyl) -1-azavinyl] phenoxy} phenyl} sulfone)
Melting point 143 ° C (differential scanning calorimetry)
Step (3): Synthesis of benzoxazine compound "comparative compound" Bis {4- (4- {[(2-hydroxyphenyl) methyl] amino} phenoxy) phenyl synthesized in step (2) in a 5-liter four-necked flask. } 244 g of sulfone and 1222 g of 1,4-dioxane were charged, and 81 g of a 35% formalin aqueous solution was added dropwise at 40 ° C. After completion of the dropping, the mixture was stirred at 40 ° C. for 3.5 hours.
This liquid was heated to 68 ° C. to dissolve the crystals precipitated by the reaction, and then 1221 g of toluene was added and heated again. After cooling this solution from 66.5 ° C to 5 ° C, the precipitated crystals are filtered off and dried to obtain 184 g of crystals of a benzoxazine compound "comparative compound" having a purity of 100% (gel permeation chromatography analysis method). Obtained.
Yield 72.6%: Yield for bis {4- (4-{[(2-hydroxyphenyl) methyl] amino} phenoxy) phenyl} sulfone Melting point 188 ° C (differential scanning calorimetry)
1H-NMR (400MHz) measurement (solvent: CDCl3): 4.62 (s, 2H × 2: a), 5.34 (s, 2H × 2: b), 6.82 (dd, 1H × 2: c), 6.91-6.94 ( m, 5H × 2: d, e, f), 7.02 (dd, 1H × 2: g), 7.12-7.14 (m, 3H × 2: h, i), 7.80 (ddd, 2H × 2: j).

Polymerization: Polymerization of the benzoxazine compound "Comparative Compound 1" The glass transition temperature of the cured product obtained by melting the obtained benzoxazine compound "Comparative Compound 1" at 200 ° C. and curing it in an oven at 200 ° C. for 2 hours is dynamic. The tan δ value of the viscoelasticity measurement was 199 ° C.

工程（１）：ジイミン化合物＜ビス｛４－{３－[２－(２－ヒドロキシ－５－メチルフェニル)－１－アザビニル]フェノキシ}フェニル｝スルホン＞の合成
ビス｛４－（３－アミノフェニルオキシ）フェニル｝スルホン３６．２ｇ、酢酸エチル２０４．４ｇおよび５－メチルサリチルアルデヒド２５．１ｇを５００ミリリッター四つ口フラスコに仕込んだ。酢酸エチル還流下で３３．５時間撹拌した。途中、常圧下８０℃で蒸留を行い、酢酸エチルを７８．４ｇ留出させた。結晶は反応中に析出した。反応終了液を４℃まで冷却後、ろ別して分離した結晶を乾燥して、純度９９．７％（ゲルパーミエーションクロマトグラフィー分析法）のビス｛４－{３－[２－(２－ヒドロキシ－５－メチルフェニル)－１－アザビニル]フェノキシ}フェニル｝スルホンの結晶５４．０ｇを得た。
収率 ９６．４％（ビス｛４－（３－アミノフェニルオキシ）フェニル｝スルホンに対する収率）
融点 １６７．０℃（示差走査熱量測定法）
１Ｈ‐ＮＭＲ（４００ＭＨｚ）測定（溶媒：CDCl3）：2.34(s,3H×2:a), 6.94-6.99(m,3H×2:b,c,d), 7.09-7.24(m,5H×2:e,f,g,h), 7.45(t, 1H×2:i), 7.92(d, 2H×2:j), 8.57(s, 1H×2:k), 12.72(s, 1H×2:l).

工程（２）：第二級ジアミン化合物＜ビス｛４－(３－{[(２－ヒドロキシ-５-メチルフェニル)メチル]アミノ}フェノキシ)フェニル｝スルホン＞酢酸ブチル溶液の合成
１リッター四つ口フラスコに工程（１）で得られたビス｛４－{３－[２－(２－ヒドロキシ－５－メチルフェニル)－１－アザビニル]フェノキシ}フェニル｝スルホン５４．０ｇ、エタノール５４０．０ｇを仕込み、３０～３２℃で水素化ホウ素ナトリウム６．１１ｇの粉末を２時間毎に２回に分けて室温で添加した。添加後、３０℃で２３時間撹拌すると僅かに濁りのある黄色透明の溶液となった。この溶液を、２リッター四つ口フラスコに仕込んだ水６４８．０ｇとエタノール１０８．０ｇの混合液に滴下し、生成した沈殿をろ別、乾燥し、粉末６２．８ｇを得た。この粉末６２．８ｇ、水１２５．６ｇ、酢酸ブチル５０２．４ｇを１リッター四つ口フラスコに仕込み、室温～３０℃で溶解後、撹拌しながら酢酸５．３ｇで中和した。その後静置し中和分液水を分液し、水洗分液を２回繰り返し、ビス｛４－(３－{[(２－ヒドロキシ-５-メチルフェニル)メチル]アミノ}フェノキシ)フェニル｝スルホンの酢酸ブチル溶液５５４．３ｇを取得した。
純度 ９７．０％（酢酸ブチル除去値:高速液体クロマトグラフィー分析法）
溶液中の第二ジアミン化合物分子量 M+1:674 M-1:672（高速液体クロマトグラフィー質量分析）
工程（３）：ベンゾオキサジン化合物「比較化合物２」の合成
１リッター四つ口フラスコに工程（２）で合成したビス｛４－(３－{[(２－ヒドロキシ-５-メチルフェニル)メチル]アミノ}フェノキシ)フェニル｝スルホンの酢酸ブチル溶液５５４．３ｇを仕込み、３５％ホルマリン水溶液１９．７ｇを４０℃で滴下した。滴下終了後４０℃で２３．５時間撹拌して反応を完結させたが、撹拌中に結晶が析出した。反応終了液を５℃まで冷却した後、結晶をろ別し乾燥することにより、純度９９．７％（ゲルパーミエーションクロマトグラフィー分析法）のベンゾオキサジン化合物「比較化合物２」の結晶４６．８ｇを得た。
収率 ８２．９％（ビス｛４－{３－[２－(２－ヒドロキシ－５－メチルフェニル)－１－アザビニル]フェノキシ}フェニル｝スルホンに対する収率）
融点 １５７℃（示差走査熱量測定法）
１Ｈ‐ＮＭＲ（４００ＭＨｚ）測定（溶媒：CDCl3）：2.27(s,3H×2a), 4.59(s, 2H×2:b), 5.32(s, 2H×2:c), 6.59(ddd, 1H×2:d), 6.77(d, 1H×2:e), 6.80(t, 1H×2:f), 6.83(d, 1H×2:g), 6.94-6.97(m, 2H×2:h,i), 7.01(ddd, 2H×2:j), 7.27(t, 1H×2:k), 7.85(ddd, 2H×2:l).

重合：ベンゾオキサジン化合物「比較化合物２」の重合
得られたベンゾオキサジン化合物「比較化合物２」を１８０℃で融解させ、オーブン中１８０℃で２時間、２００℃で２時間硬化させた硬化物のガラス転移温度は、動的粘弾性測定のtanδ値で２０３℃であった。 <Comparative Example 2> Synthesis and polymerization of the benzoxazine compound "Comparative Compound 2" represented by the following chemical formula "Comparative Compound 2" is a compound corresponding to the compound (II-c) of Patent Document 3.

Step (1): Synthesis of diimine compound <bis {4- {3- [2- (2-hydroxy-5-methylphenyl) -1-azavinyl] phenoxy} phenyl} sulfone> Bis {4- (3-aminophenyl) 36.2 g of oxy) phenyl} sulfone, 204.4 g of ethyl acetate and 25.1 g of 5-methylsalicylic aldehyde were charged into a 500 milliliter four-necked flask. The mixture was stirred under reflux with ethyl acetate for 33.5 hours. On the way, distillation was carried out at 80 ° C. under normal pressure to distill 78.4 g of ethyl acetate. Crystals precipitated during the reaction. After cooling the reaction completion solution to 4 ° C., the separated crystals are dried by filtration and bis {4- {3- [2- (2-hydroxy-) with a purity of 99.7% (gel permeation chromatography analysis method). 54.0 g of crystals of 5-methylphenyl) -1-azavinyl] phenoxy} phenyl} sulfone was obtained.
Yield 96.4% (Yield for bis {4- (3-aminophenyloxy) phenyl} sulfone)
Melting point 167.0 ° C (differential scanning calorimetry)
1H-NMR (400MHz) measurement (solvent: CDCl3): 2.34 (s, 3H × 2: a), 6.94-6.99 (m, 3H × 2: b, c, d), 7.09-7.24 (m, 5H × 2) : e, f, g, h), 7.45 (t, 1H × 2: i), 7.92 (d, 2H × 2: j), 8.57 (s, 1H × 2: k), 12.72 (s, 1H × 2) : l).

Step (2): Secondary diamine compound <bis {4- (3-{[(2-hydroxy-5-methylphenyl) methyl] amino} phenoxy) phenyl} sulfone> Synthesis of butyl acetate solution 1 liter 4 mouths The flask was charged with 54.0 g of the bis {4- {3- [2- (2-hydroxy-5-methylphenyl) -1-azavinyl] phenoxy} phenyl} sulfone obtained in the step (1) and 540.0 g of ethanol. , A powder of 6.11 g of sodium boron hydride at 30-32 ° C. was added every 2 hours in 2 portions at room temperature. After the addition, the mixture was stirred at 30 ° C. for 23 hours to obtain a slightly turbid yellow transparent solution. This solution was added dropwise to a mixed solution of 648.0 g of water and 108.0 g of ethanol charged in a 2-liter four-necked flask, and the generated precipitate was filtered off and dried to obtain 62.8 g of powder. 62.8 g of this powder, 125.6 g of water, and 502.4 g of butyl acetate were placed in a 1-liter four-necked flask, dissolved at room temperature to 30 ° C., and then neutralized with 5.3 g of acetic acid with stirring. After that, let stand to separate the neutralized liquid, and repeat the washing with water twice to repeat bis {4- (3-{[(2-hydroxy-5-methylphenyl) methyl] amino} phenoxy) phenyl} sulfone. 554.3 g of a butyl acetate solution of the above was obtained.
Purity 97.0% (Butyl acetate removal value: High performance liquid chromatography analysis method)
Molecular Weight of Second Diamine Compound in Solution M + 1: 674 M-1: 672 (High Performance Liquid Chromatography Mass Spectrometry)
Step (3): Synthesis of benzoxazine compound "Comparative Compound 2" Bis {4- (3-{[(2-hydroxy-5-methylphenyl) methyl] synthesized in step (2) in a 1-liter four-necked flask] 554.3 g of a butyl acetate solution of amino} phenoxy) phenyl} sulfone was charged, and 19.7 g of a 35% formalin aqueous solution was added dropwise at 40 ° C. After the completion of the dropping, the reaction was completed by stirring at 40 ° C. for 23.5 hours, but crystals were precipitated during stirring. After cooling the reaction completion solution to 5 ° C., the crystals are separated and dried to obtain 46.8 g of crystals of the benzoxazine compound "Comparative Compound 2" having a purity of 99.7% (gel permeation chromatography analysis method). Obtained.
Yield 82.9% (Yield for bis {4- {3- [2- (2-hydroxy-5-methylphenyl) -1-azavinyl] phenoxy} phenyl} sulfone)
Melting point 157 ° C (differential scanning calorimetry)
1H-NMR (400MHz) measurement (solvent: CDCl3): 2.27 (s, 3H × 2a), 4.59 (s, 2H × 2: b), 5.32 (s, 2H × 2: c), 6.59 (ddd, 1H ×) 2: d), 6.77 (d, 1H × 2: e), 6.80 (t, 1H × 2: f), 6.83 (d, 1H × 2: g), 6.94-6.97 (m, 2H × 2: h, i), 7.01 (ddd, 2H × 2: j), 7.27 (t, 1H × 2: k), 7.85 (ddd, 2H × 2: l).

Polymerization: Polymerization of the benzoxazine compound "Comparative Compound 2" The obtained benzoxazine compound "Comparative Compound 2" was melted at 180 ° C. and cured in an oven at 180 ° C. for 2 hours and at 200 ° C. for 2 hours. The transition temperature was 203 ° C. as the tan δ value of the dynamic viscoelasticity measurement.

Claims (1)

A benzoxazine compound represented by the general formula (1).

(In the formula, X represents a sulfonyl group.)