TWI501954B - Facile synthesis of benzoxazines and substituted benzoxazines via one-pot/two-pot procedure and use thereof - Google Patents

Description

One-pot/two-pot manufacturing method and use of oxo-nitrobenzocyclohexane (BENZOXAZINE) resin and substituted oxo-nitrobenzo-cyclohexane resin

The present invention discloses a novel oxonitrobenzocyclohexane resin. The present invention also discloses a one-pot/two-pot process for a novel synthetic oxo-nitrobenzocyclohexane resin utilizing mono- or polyfunctional amines or nitros with ortho-hydroxyl groups. A ketone or aldehyde to synthesize an oxoazobenzocyclohexane resin.

Phenolic resin is a commonly used thermosetting resin obtained by polycondensation of a phenolic monomer and an aldehyde monomer. The oxo-nitrobenzocyclohexane resin developed in recent years is also a kind of phenolic resin, which is characterized in that the monomer is ring-hardened after heating, but does not release water when hardened, so it is better than phenolic resin. Processability.

The most commonly used oxo-nitrobenzocyclohexane resins are Bm and Ba. Bm is synthesized from bisphenol A, formaldehyde and methylamine [1], and Ba is synthesized from bisphenol A, formaldehyde and aniline [2]. The synthesis method of Bm and Ba is as follows:

At present, almost all oxo-nitrobenzocyclohexane resins are synthesized from bisphenol A, formaldehyde and monofunctional amines. If a difunctional amine, formaldehyde, and a monofunctional phenol are used to synthesize an oxoazobenzocyclohexane resin, then -NCH ₂ OH will be condensed with NH _{2 of} aniline to form a high molecular weight insoluble, -NCH ₂ The equation for the NH ₂ condensation water of OH and aniline is as follows:

In addition, in the synthesis of oxoazobenzocyclohexane resin, aromatic amines form an intermediate of tris(1,3,5,-triarylhexahydro-1,3,5-triazine) with formaldehyde. The network structure of the trinitrogen heterocycle causes cross-linking to form insoluble matter. Therefore, when an oxoazobenzocyclohexane resin is synthesized from a difunctional amine, formaldehyde, and a monofunctional phenol, there are disadvantages such as generation of a high molecular weight insoluble matter, poor purity, low yield, and the like.

In order to improve the above-mentioned disadvantages of the synthesis of oxobenzobenzocyclohexane resin by aromatic bisamine, a new synthesis method has been proposed [3], and the flow is as follows:

The method utilizes a bisamine to react with 2-hydroxybenzaldehyde to obtain a compound having a C=N double bond structure, followed by reduction of a double bond using a reducing agent sodium borohydride (NaBH ₄ ), and then using formaldehyde. The dehydration ring is closed, and finally an aromatic oxo-nitrobenzocyclohexane resin is obtained.

Although the above method can smoothly obtain an oxoazobenzocyclohexane resin based on an aromatic bisamine, the method is not advantageous for industrial production because of various synthesis steps; in addition, because of the reactivity of ketones and diamines Far less than the reactivity of aldehydes and diamines, so this method can only be used as a starting material for the aldehydes of the ortho-hydroxyl group, such as 2-hydroxybenzaldehyde and its derivatives. Things. If a ketone having an ortho-hydroxyl group, such as 2-hydroxyacetophenone, is used, it cannot be reacted with a bisamine.

references:

[1] Ninc X., Ishida H. J. Polym. Sci. Part A: Polym. Chem. 1994, 32, 1121.

[2] Ishida H., Rodriguez Y. Polymer 1995, 36, 3151.

[3] Lin C.H., Chang S.L., Hsieh C.W., Lee H.H. Polymer 2008, 49, 1220.

SUMMARY OF THE INVENTION The object of the present invention is to provide a novel oxonitrobenzocyclohexane resin and a process for preparing the oxonitrobenzocyclohexane resin. The method of the invention simplifies the previous three-step process to synthesize the oxo-nitrobenzocyclohexane resin, so as to facilitate industrial production, and the reaction can be carried out from the amine-based precursor nitro group, thereby greatly reducing the raw material cost. In addition, in the past, it was necessary to select a reactive aldehyde (such as 2-hydroxybenzaldehyde) to react with a bisamine, and if a less reactive ketone (such as 2-hydroxyacetophenone) was used, it could not be combined with a bisamine. Carry out the reaction. The present invention overcomes this limitation by using a ketone as a starting material to synthesize an oxonitrobenzocyclohexane resin.

According to one of the objects of the present invention, an oxonitrobenzocyclohexane resin represented by the formula (1) is disclosed. Wherein n is 1, 2 or 3; R is selected from the group consisting of C ₁ -C ₆ alkyl, C ₃ -C ₇ cycloalkyl, CF ₃ and a group consisting of; R ₁ to R ₄ are each independently selected from the group consisting of hydrogen, hydroxyl, C ₁ -C ₆ alkyl, C ₁ -C ₆ alkoxy, CF ₃ , OCF ₃ , phenyl, halogen, benzene a group consisting of an oxy group and a C ₃ -C ₇ cycloalkyl group; Q is a single bond,

When n=2, W is selected from the following groups:

When n=3, W is selected from the following groups or

When n=1 and Q is a single bond, W is

T is selected from the group consisting of hydrogen, C ₁ -C ₆ alkyl, hydroxyl, C ₁ -C ₆ alkoxy, amine, carboxyl, CF ₃ , phenyl, halogen, phenoxy and C ₃ -C ₇ rings a group consisting of alkyl groups; Y and Z groups are each independently selected from the group consisting of hydrogen, C ₁ -C ₆ alkyl, C ₁ -C ₆ alkoxy, CF ₃ , phenyl, halogen, phenoxy and C ₃ -C _A group consisting of ₇ cycloalkyl groups.

When R of the above formula (1) oxobenzobenzocyclohexane resin is CH ₃ , W is a phenyl group, R ₁ to R _{2 are} each a hydrogen atom, Q is a single bond, and when n is 2, the formula ( 1) One of the embodiments of the oxonitrobenzoxylene resin may be

The above oxynitride benzocyclohexane resin of the formula (1) can be used as a latent epoxy resin hardener.

Another object of the present invention is to provide a potting/two-pot method for preparing an oxonitrobenzocyclohexane resin of the above formula (1), which utilizes a ketone having an ortho-hydroxyl group. Synthesizing oxonitrobenzocyclohexane resins such as 2-hydroxyacetophenone or aldehydes such as 2-hydroxybenzaldehyde with a mono- or polyfunctional amine or nitro group, of which The potting/two-pot method involves a reduction reaction of a nitro group.

In the two-pot method, first, a ketone or an aldehyde having an ortho-hydroxyl group and an amine or a nitro group having a mono- or polyfunctional group are dissolved in a solvent, and a reducing agent is added. Or a reducing agent/touch coal, the reaction is stirred under a hydrogen atmosphere at a temperature ranging from room temperature to 100 ° C to form an intermediate, and at this time, the reaction mixture may be dropped into an aqueous methanol solution to precipitate a product. The intermediate is then dissolved in a solvent, and formaldehyde is added to the mixture at room temperature for a period of time to raise the temperature to 60 ° C to reflux temperature. Finally, the solution was dropped into an aqueous methanol solution or the solvent was distilled off on a rotary evaporator to precipitate a product.

As for the one-pot method, the ketone or aldehyde having an ortho-hydroxyl group and an amine or a nitro group having a mono- or poly-functional group are first dissolved in a solvent, and a reducing agent or a reducing agent/touch is added. The coal was continuously stirred at room temperature to 100 ° C under a hydrogen atmosphere for a while, then formaldehyde was added, and the reactor was heated to 60 ° C to reflux temperature and stirring was continued. Finally, the solution was dropped into an aqueous methanol solution to precipitate a product.

The present invention provides a two-pot process for preparing an oxonitrobenzocyclohexane resin of the above formula (1), which comprises the steps of: (1) an aldehyde having an ortho-hydroxyl group of the formula (2) or The ketone compound is dissolved in a solvent with a mono- or polyfunctional amine or a nitro group of the formula (3), and a reducing agent or a reducing agent/catalyst is added, and the reaction is stirred under a hydrogen atmosphere at room temperature to 100 ° C to form a formula (4). Intermediate;

(2) dissolving the intermediate of the formula (4) in a solvent, adding formaldehyde to the mixture at room temperature for a period of time, raising the temperature to 60 ° C to reflux temperature, removing the solvent from the solution, and precipitating the product; wherein the A ^m are each other Independently a hydrogen atom or an oxygen atom; R ₁ to R ₂ are as defined above; R is as defined above or as H; W, Q and n are as defined above; and m is an integer from 1 to n.

The present invention also provides a method for preparing a oxoxobenzocyclohexane resin of the above formula (1), which comprises the following steps: (1) an aldehyde having an ortho-hydroxyl group of the formula (2) Or a ketone compound and a mono- or polyfunctional amine or a nitro group of the formula (3) are dissolved in a solvent, and a reducing agent or a reducing agent/catalyst is added, and the reaction is continuously stirred at room temperature to 100 ° C in a hydrogen atmosphere, and added. Formaldehyde, warmed to 60 ° C to reflux temperature to make it react for a period of time; (2) remove the solvent to precipitate the product; wherein A ^m and m are defined as before; R ₁ ~ R ₂ are as defined before; R The definition is as before or H; and W, Q and n are defined as before.

Among the above methods, the solvent used in each step is well known in the art. For example, the solvent of the step (1) in the one-pot method and the two-pot method may be NN-dimethylvinylamine (DMAc) or ethanol (Ethanol), and the solvent used in the step (2) in the two-pot method is Dioxane or Chloroform.

The reducing agent or reducing agent/catalyst used in the above method is selected from lithium aluminum hydride (LiAlH ₄ ), hydrazine/palladium carbon catalyst (Pd/C), stannous chloride (SnCl ₂ )/palladium. A group consisting of a carbon catalyst (Pd/C), sodium borohydride (NaBH ₄ ), hydrogen (H ₂ )/palladium carbon catalyst (Pd/C), and hydrogen (H ₂ )/nickel (Ni).

One of the characteristics of the method of the present invention is that a single or polyfunctional amine (such as a monoamine, a bisamine, a guanamine, etc.), a mono- or polyfunctional nitro group has an amine group and a nitrate after hydrogenation reaction or a structure. The thiol-cyclohexane resin having a different structure is obtained by reacting a monomer with a ketone or an aldehyde having an ortho-hydroxy group.

In the above method, the difunctional amine or nitro group is selected from an aromatic amine group or a nitro group, an aromatic amine group or a nitro group having an ether group in the para position, an aromatic amine group having an ether group in the meta position or A group consisting of a nitro group, a benzene ring/naphthylcycloamino group or a nitro group and an aromatic amine group or a nitro group having a substituent.

In the above method, the hydrogen atom or oxygen atom represented by A ^m may also be represented herein by A, B and C as described below.

According to the above method, when the difunctional amine group or nitro group used is represented by the following formula (5) Wherein A and B are each independently a hydrogen atom or an oxygen atom; and X is selected from the group consisting of:

An oxobenzobenzocyclohexane resin represented by the formula (6) can be synthesized

This synthesis can be represented by the following process:

Further, according to the above method, when the difunctional amine group or the nitro group used is an aromatic amine group or a nitro group having an ether group as shown in the following formula (7), Wherein A, B, X and Y are as defined above, and the oxobenzobenzocyclohexane resin represented by formula (8) can be synthesized.

This synthesis can be represented by the following process:

Further, according to the above method, when the difunctional amine group or the nitro group used is an aromatic amine group or a nitro group having an ether group as shown in the following formula (9), Wherein Ar is selected from the group consisting of: The A, B, Y and Z systems are as defined above, and the oxoazobenzocyclohexane resin represented by the formula (10) can be synthesized.

This synthesis can be represented by the following process:

Further, according to the above method, when the difunctional amine group or the nitro group used is an aromatic amine group or a nitro group having an ether group at the position represented by the following formula (11), Wherein A, B and X are as defined above, and the oxobenzobenzocyclohexane resin represented by formula (12) can be synthesized.

This synthesis can be represented by the following process:

Further, according to the above method, when the difunctional amine group or the nitro group used is an aromatic amine group or a nitro group having an ether group at the position represented by the following formula (13), Wherein A, B and Ar are as defined above, and an oxobenzobenzocyclohexane resin represented by formula (14) can be synthesized.

This synthesis can be represented by the following process:

Further, according to the above method, when the difunctional amine group or nitro group used is a benzene ring/naphthalene ring amine group or a nitro group represented by the following formula (15), A ₂ N-Ar-NB ₂ (15) wherein A , B and Ar are defined as before, and the oxo-nitrobenzocyclohexane resin represented by the formula (16) can be synthesized.

This synthesis can be represented by the following process:

Further, according to the above method, when the difunctional amine group or the nitro group used is a substituent-containing amine group or a nitro group represented by the following formula (17), Wherein A, B, X, Y and Z are as defined above, and an oxobenzobenzocyclohexane resin represented by formula (18) can be synthesized.

This synthesis can be represented by the following process:

According to the above method, when a hydrazine-functional amine group or a nitro group represented by the following formula (19) is used, Wherein A, B and C independently of each other may be a hydrogen atom or an oxygen atom, and X, Y and Z are as defined above, and an oxobenzobenzocyclohexane resin represented by formula (20) may be synthesized.

This synthesis can be represented by the following process:

According to the above method, when the hydrazine-functional amine group or nitro group used is an oxime-functional amine group or a nitro group having an ether group represented by the following formula (21), Wherein A, B and C independently of each other may be a hydrogen atom or an oxygen atom, and X, Y and Z are as defined above, and an oxobenzobenzocyclohexane resin represented by formula (22) may be synthesized.

This synthesis can be represented by the following process:

According to the above method, when the hydrazine-functional amine group or nitro group used is represented by the following formula (23), Wherein A, B and C may be a hydrogen atom or an oxygen atom, and an oxoazobenzocyclohexane resin represented by the formula (24) may be synthesized.

This synthesis can be represented by the following process:

The invention is further illustrated by the following examples, which are not intended to limit the scope of the invention, and any modifications and variations which may be obtained without departing from the spirit of the invention are range.

Example

The implementation of the above related inventions will be illustrated by the following specific examples.

Example 1 Synthesis of p-HB-Bz by two-pot method using p-phenylenediamine

To synthesize P-HB-Bz by the two-pot method of the present invention, please refer to the flow shown in FIG. 1A.

Take 24.84 g (0.2 mol) of 2-hydroxybenzaldehyde, 10 g (0.09 mol) of p-phenylenediamine, 0.3 g of Pd/C and 100 ml of DMAc in a high pressure reactor at room temperature in a hydrogen atmosphere. After stirring the reaction for a while, the Pd/C was suction-filtered, and the filtrate was poured into an aqueous methanol solution to precipitate an intermediate product p-HB-r. Fig. 1B is a ¹ H-NMR chart of the intermediate product p-HB-r, from which it was confirmed that the intermediate product p-HB-r was smoothly synthesized.

Next, p-HB-r was dissolved in chloroform, formaldehyde was added, and the mixture was stirred at room temperature for a while, and then the temperature was raised to reflux temperature for 12 hours. Finally, the solution was evaporated to dryness on a rotary evaporator to precipitate product. Fig. 1C is a ¹ H-NMR chart of p-HB-Bz, from which the structure of p-HB-Bz was confirmed to be correct.

Figure 1D is a DSC scan of p-HB-Bz. The DSC results show that p-HB-Bz has a broad processing window and exhibits good processability. The end is provided with an oxoazobenzocyclohexane group. -HB-Bz, which releases OH groups after heat hardening Epoxy resin reaction, regarded as a new type of latent epoxy resin hardener.

Example 2 Synthesis of p-HB-Bz by two-pot method using p-nitroaniline

To synthesize p-HB-Bz by the two-pot method of the present invention, please refer to the flow shown in FIG.

19.5 g (0.16 mol) of 2-hydroxybenzaldehyde, 10 g (0.07 mol) of p-nitroaniline, 0.3 g of Pd/C and 100 ml of DMAc were placed in a high pressure reactor at room temperature in a hydrogen atmosphere. After stirring the reaction for a while, the Pd/C was suction-filtered, and the filtrate was poured into an aqueous methanol solution to precipitate an intermediate product p-HB-r. The p-HB-r structure synthesized from p-nitroaniline as the starting material was identified by the ¹ H-NMR structure, and the p-HB-r structure synthesized from p-phenylenediamine was the same, and the structure was confirmed to be correct. .

Next, p-HB-r was dissolved in chloroform, formaldehyde was added, and the mixture was stirred at room temperature for a while, and then the temperature was raised to reflux temperature for 12 hours. Finally, the solution was evaporated to dryness on a rotary evaporator to precipitate product. The structure was identified by ¹ H-NMR, and the structure of p-HB-Bz was confirmed to be correct.

Example 3 Synthesis of p-HB-Bz by one-pot method using p-phenylenediamine

To synthesize p-HB-Bz by one of the potting methods of the present invention, please refer to the flow shown in FIG.

Take 24.84 g (0.2 mol) of 2-hydroxybenzaldehyde, 10 g (0.09 mol) of p-phenylenediamine, 0.3 g of Pd/C and 100 ml of DMAc in a high pressure reactor at room temperature in a hydrogen atmosphere. The intermediate product p-HB-r is obtained after stirring the reaction for a while. At this time, 16.51 g (0.2 mol) of formaldehyde was further added to the high-pressure reactor, and the mixture was heated to 70 ° C for 12 hours, and then Pd/C was filtered, and the filtrate was poured into an aqueous methanol solution to precipitate a product. The p-HB-Bz structure synthesized by the one-pot method was identified by the ¹ H-NMR structure, and the structure was confirmed to be correct.

Example 4 Synthesis of p-HB-Bz by one-pot method using p-nitroaniline

To synthesize p-HB-Bz by one of the potting methods of the present invention, please refer to the flow shown in FIG.

19.5 g (0.16 mol) of 2-hydroxybenzaldehyde, 10 g (0.07 mol) of p-nitroaniline, 0.3 g of Pd/C and 100 ml of DMAc were placed in a high pressure reactor at room temperature in a hydrogen atmosphere. The intermediate product p-HB-r is obtained after stirring the reaction for a while. At this time, 16.51 g (0.2 mol) of formaldehyde was further added to the high-pressure reactor, and the mixture was heated to 70 ° C for 12 hours, and then Pd/C was filtered, and the filtrate was poured into an aqueous methanol solution to precipitate a product. The p-HB-Bz structure synthesized by the one-pot method from p-nitroaniline as the starting material was identified by the ¹ H-NMR structure, and the structure was confirmed to be correct.

Example 5 Synthesis of DDM-HB-Bz by one-pot method using 4,4-diaminodiphenyl methane (DDM)

To synthesize DDM-HB-Bz by one of the potting methods of the present invention, please refer to the flow shown in FIG. 5A.

13.56 g (0.11 mol) of 2-hydroxybenzaldehyde, 10 g (0.05 mol) of DDM, 3 g of Pd/C and 100 ml of DMAc were placed in a high pressure reactor and stirred at room temperature under hydrogen atmosphere. After a period of time, 9.01 g of formaldehyde (0.11 mol) was added, and the mixture was heated to 70 ° C for 12 hours, and then Pd/C was filtered, and the filtrate was poured into an aqueous methanol solution to precipitate a product. Fig. 5B shows the results of structural identification of ¹ H-NMR, and it was confirmed that DDM-HB-Bz can be obtained smoothly by one-pot method.

Example 6 Synthesis of ODA-HB-Bz by one-pot method using 4,4-diaminodiphenyl ether (ODA)

To synthesize ODA-HB-Bz by one of the potting methods of the present invention, please refer to the flow shown in Fig. 6A.

Take 13.56 g (0.11 mol) of 2-hydroxybenzaldehyde, 10 g (0.05 mol) of ODA, 3 g of Pd/C and 100 ml of DMAc in a high pressure reactor, and stir the reaction under a hydrogen atmosphere at room temperature. After a period of time, 9.01 g of formaldehyde (0.11 mol) was added, and the mixture was heated to 70 ° C for 12 hours, and then Pd/C was filtered, and the filtrate was poured into an aqueous methanol solution to precipitate a product. Fig. 6B shows the results of structural identification of ¹ H-NMR, and it was confirmed that ODA-HB-Bz can be obtained smoothly by one-pot method. Fig. 6C is a DSC scan of ODA-HB-Bz, and it is confirmed from the exothermic peak in the figure that ODA-HB-Bz which can be self-crosslinking reaction is smoothly obtained.

Comparative example 1 Synthesis of p-HB-Bz by three-step method using p-phenylenediamine

10 g of p-phenylenediamine (92.5 mmol), 22.58 g of 2-hydroxybenzaldehyde (185.1 mmol) and dimethylformamide (DMF) 100 mL were added to a three-neck reactor and reacted under nitrogen atmosphere. After the hour, the p-HB orange powder was precipitated by dropping into an aqueous methanol solution, and suction filtration was performed. The powder obtained by suction filtration was dried in a vacuum oven at a yield of 90%, and its structural correctness was confirmed by ¹ H-NMR.

Next, an intermediate p-HB-r was synthesized. The reactor was first purged with nitrogen, and after removing water for half an hour, the nitrogen was turned off and a hydrogen balloon was charged. 10 g of p-HB (31.6 mmol), 3.85 g of NaBH ₄ (101.2 mmol) and 100 mL of ethanol were added to the three-neck reactor, reacted at room temperature for 12 hours, and then dropped into water to precipitate a white powder. After filtration, it was dried in a vacuum oven at a yield of 85%, and the structure of p-HB-r was confirmed to be correct by ¹ H-NMR analysis.

Finally, 10 g of p-HB-r (31.24 mmol), formaldehyde 5.574 g (68.7 mmol) and 100 mL of chloroform were placed in a three-neck reactor, reacted at room temperature for 5 hours, and then heated to reflux for 12 hours. The p-HB-Bz yellow powder was obtained by removing the solvent using a rotary evaporator.

Example 7 Synthesis of p-HA-Bz by two-pot method using p-phenylenediamine

The synthesis of p-HA-Bz of this example is similar to that of Example 1. Now, 2-hydroxyacetophenone is substituted for 2-hydroxybenzaldehyde to synthesize p-HA-Bz, and p-HA-Bz is synthesized by two-pot method. Please refer to FIG. 7A for the flow.

Take 27.70 g (0.2 mol) of 2-hydroxyacetophenone and 10 g (0.09 mol) of p-phenylenediamine, 0.3 g of Pd/C and 100 ml of DMAc in a high pressure reactor at 65 ° C for hydrogen After stirring the reaction for a while, Pd/C was filtered, and the filtrate was poured into an aqueous methanol solution to precipitate an intermediate product p-HA-r. Fig. 7B is a ¹ H-NMR chart of the intermediate product p-HA-r, from which it was confirmed that the intermediate product p-HA-r was smoothly synthesized.

Next, p-HA-r was dissolved in chloroform, formaldehyde was added, and the mixture was stirred at room temperature for a while, and then the temperature was raised to reflux temperature for 12 hours. Finally, the solution was evaporated to dryness on a rotary evaporator to precipitate product and recrystallized from ethanol. Fig. 7C is a ¹ H-NMR chart of p-HA-Bz, from which it was confirmed that p-HA-Bz was successfully synthesized.

Fig. 7D is a DSC scan of p-HA-Bz, and the exothermic peak in the figure can indirectly confirm the smooth synthesis of p-HA-Bz which can be self-opened and crosslinked.

Example 8 Synthesis of p-HA-Bz by two-pot method using p-nitroaniline

The synthesis of p-HA-Bz in this example is similar to that of Example 7. Now, p-HA-Bz can be synthesized by using p-nitroaniline instead of p-phenylenediamine. The procedure for synthesizing p-HA-Bz by two-pot method is described. Figure 8.

21.77 g (0.16 mol) of 2-hydroxyacetophenone and 10 g (0.07 mol) of p-nitroaniline, 0.3 g of Pd/C and 100 ml of DMAc were placed in a high pressure reactor at 65 ° C. After stirring the reaction for a while, Pd/C was filtered, and the filtrate was poured into an aqueous methanol solution to precipitate an intermediate product p-HA-r. The p-HA-r structure synthesized from p-nitroaniline as the starting material was identified by the ¹ H-NMR structure, and the p-HA-r structure synthesized from p-phenylenediamine was the same, and the structure was confirmed to be correct. .

Next, p-HA-r was dissolved in chloroform, formaldehyde was added, and the mixture was stirred at room temperature for a while, and then the temperature was raised to reflux temperature for 12 hours. Finally, the solution was evaporated to dryness on a rotary evaporator to precipitate product. It was confirmed by ¹ H-NMR structure identification that the structure was correct.

Example 9 Synthesis of p-HA-Bz by one-pot method using p-phenylenediamine

To synthesize p-HA-Bz by one of the potting methods of the present invention, please refer to the flow shown in FIG.

Take 27.70 g (0.2 mol) of 2-hydroxyacetophenone and 10 g (0.09 mol) of p-phenylenediamine, 0.3 g of Pd/C and 100 ml of DMAc in a high pressure reactor at 65 ° C for hydrogen The intermediate product p-HA-r can be obtained after stirring the reaction for a period of time in an environment. At this time, 16.51 g (0.2 mol) of formaldehyde was further added to the high-pressure reactor, and after maintaining the reaction at 70 ° C for 12 hours, Pd/C was filtered, and the filtrate was poured into an aqueous ethanol solution to precipitate a product. The p-HA-Bz structure synthesized by the one-pot method was identified by the ¹ H-NMR structure, and the structure was confirmed to be correct.

Example 10 Synthesis of p-HA-Bz by one-pot method using p-nitroaniline

To synthesize p-HA-Bz by one of the potting methods of the present invention, please refer to the flow shown in FIG.

21.77 g (0.16 mol) of 2-hydroxyacetophenone and 10 g (0.07 mol) of p-nitroaniline, 0.3 g of Pd/C and 100 ml of DMAc were placed in a high pressure reactor at 65 ° C. The intermediate product p-HA-r can be obtained after stirring the reaction for a period of time in an environment. At this time, 16.51 g (0.2 mol) of formaldehyde was further added to the high-pressure reactor, and after maintaining the reaction at 70 ° C for 12 hours, Pd/C was filtered, and the filtrate was poured into an aqueous ethanol solution to precipitate a product. The p-HA-Bz structure synthesized by the one-pot method using p-nitroaniline as a starting material was identified by the ¹ H-NMR structure, and the structure was confirmed to be correct.

Comparative example 2 Synthesis of p-HA-Bz by three-step method using p-phenylenediamine

2 g of p-phenylenediamine (18.51 mmol), 5.5392 g of 2-hydroxyacetophenone (40.71 mmol) and DMAc 20 mL were added to the reactor, and the temperature was raised to 70 ° C for 12 hours under nitrogen atmosphere. A bright yellow powder precipitated. It was identified by ¹ H-NMR and MASS as the reaction unilateral NH ₂ or the raw material structure, and p-HA having a bilateral imine structure could not be obtained smoothly, and the reduction and condensation ring closure reaction could not be continued.

Example 11 Preparation of p-HB-Bz as epoxy resin hardener

p-HB-Bz and its precursor p-phenylenediamine as epoxy resin bisphenol A diglycidyl ether (DGEBA), dicyclopentadiene epoxy resin (HP 7200) and phosphomethyl phenolic epoxy The hardener of the resin (CNE) was uniformly mixed at an equivalent ratio of 1:1, and after curing, the following comparative analysis was carried out.

Fig. 11 is a graph showing the heating rate of 10 ° C / min by differential scanning scanning analyzer (DSC) after p-HB-Bz and p-phenylenediamine were uniformly mixed with phosphomethyl phenolic epoxy resin (CNE), respectively. It can be clearly observed from the figure that the p-phenyleneamine/CNE system has a reaction exotherm at about 100 ° C, while the p-HB-Bz/CNE system passes the p-HB-Bz melting point (166 ° C). The cross-linking reaction with CNE started at 220 °C, and it has a fairly wide processing window. It can be known from DSC that oxo-nitrobenzoxene and epoxy resin have good storage stability and good processing characteristics. . In summary of the above advantages, oxobenzobenzocyclohexane is regarded as a novel latent type hardener, which greatly increases industrial applications.

Figure 12 is a graph showing the dynamic viscosity of p-HB-Bz and p-phenylenediamine and three epoxy resins at a heating rate of 5 ° C / min.

The results show that the storage modulus of the p-HB-Bz/epoxy resin system is between 1.42 and 2.16 GPa, which is slightly lower than that of the p-diamine/epoxy resin system, mainly due to the oxo-nitrobenzoxanone. The phenolic OH produced after the thermal ring opening is further subjected to a ring-opening crosslinking reaction with an epoxy resin to cause a large amount of soft ether-based segment formation, but the hydrogen bond between the OH groups makes the intermolecular The increase in force makes the glass transition temperature of p-HB-Bz as the epoxy resin hardener system higher than that of p-phenylenediamine as the hardener.

1A is a synthetic scheme for synthesizing p-HB-Bz by a two-pot method using p-phenylenediamine.

Figure 1B is a ¹ H-NMR chart of the intermediate p-HB-r.

Figure 1C is a ¹ H-NMR chart of p-HB-Bz.

Figure 1D is a DSC scan of p-HB-Bz.

2 is a synthetic scheme for synthesizing p-HB-Bz by a two-pot method using p-nitroaniline.

Figure 3 is a synthetic scheme for the synthesis of p-HB-Bz by a one-pot method using p-phenylenediamine.

Figure 4 is a synthetic scheme for the synthesis of p-HB-Bz by a one-pot method using p-nitroaniline.

Figure 5A shows the synthetic scheme for the synthesis of DDM-HB-Bz by a one-pot method using 4,4-diaminodiphenylmethane.

Figure 5B is a ¹ H-NMR chart of DDM-HB-Bz.

Figure 6A shows the synthetic scheme for the synthesis of ODA-HB-Bz by a one-pot method using 4,4-diaminodiphenyl ether.

Fig. 6B is a ¹ H-NMR chart of ODA-HB-Bz.

Figure 6C is a DSC scan of ODA-HB-Bz.

Fig. 7A is a synthetic scheme for synthesizing p-HA-Bz by a two-pot method using p-phenylenediamine.

Figure 7B is a ¹ H-NMR chart of the intermediate p-HA-r.

Figure 7C is a ¹ H-NMR chart of p-HA-Bz.

Figure 7D is a DSC scan of p-HA-Bz.

Figure 8 is a synthetic scheme for synthesizing p-HA-Bz by two-pot method using p-nitroaniline.

Figure 9 is a synthetic scheme for the synthesis of p-HA-Bz by a one-pot method using p-phenylenediamine.

Figure 10 is a synthetic scheme for the synthesis of p-HA-Bz by a one-pot method using p-nitroaniline.

Figure 11 is a DSC scan of p-HA-Bz and p-phenylenediamine mixed with CNE.

Figure 12 is a DMA scan of p-HA-Bz and p-phenylenediamine mixed with three epoxy resins.

The following patent claims are intended to define the scope of the invention. It should be understood that the obvious modifications that can be made by the skilled person based on the disclosure of the present invention are also within the scope of the present invention.

Claims (18)

An oxonitrobenzocyclohexane resin of the formula (1), Wherein n is 1, 2 or 3; R is selected from C ₁ -C ₆ alkyl; and R ₁ to R ₂ are each independently selected from hydrogen, hydroxyl, C ₁ -C ₆ alkyl, C ₁ -C ₆ a group consisting of an alkoxy group, a CF ₃ group, an OCF ₃ group, a phenyl group, a halogen group, a phenoxy group, and a C ₃ -C ₇ cycloalkyl group; Q is a single bond, , , , When n=2, W is selected from the following groups: When n=3, W is selected from the following groups When n=1 and Q is a single bond, W is T is selected from the group consisting of hydrogen, C ₁ -C ₆ alkyl; and Y and Z are each independently selected from the group consisting of hydrogen and C ₁ -C ₆ alkyl. The oxoazobenzocyclohexane resin of the formula (1), wherein R is CH ₃ , W is a phenyl group, R ₁ to R _{2 are} each a hydrogen atom, Q is a single bond, and n is 2 , the formula (1) oxo-nitrobenzocyclohexane resin is of the formula (p-HA-Bz) A use of the oxynitrobenzo-cyclohexane resin of the formula (1) of claim 1 as a latent epoxy resin hardener. A two-pot process for preparing an oxonitrobenzocyclohexane resin of the formula (1) of claim 1, which comprises the steps of: (1) a ketone compound having an ortho-hydroxyl group of the formula (2) Dissolving with the formula (3) mono- or polyfunctional amines or nitros in a solvent, and adding a reducing agent or a reducing agent/catalyst, stirring at room temperature to 100 ° C under hydrogen atmosphere to form an intermediate of formula (4) ; (2) dissolving the intermediate of the formula (4) in a solvent, adding formaldehyde to the mixture at room temperature for a period of time, then raising the temperature to 60 ° C to reflux temperature, removing the solvent from the solution to precipitate the product; wherein the A series are independent of each other It is a hydrogen atom or an oxygen atom; R ₁ to R ₂ are defined in claim 1; R is defined as the same as claim 1; W, Q and n are defined in claim 1. A method for preparing a oxobenzobenzocyclohexane resin of the formula (1) of claim 1, which comprises the steps of: (1) a ketone compound having an ortho-hydroxy group of the formula (2) Dissolve with the formula (3) mono- or polyfunctional amines or nitros in a solvent, and add a reducing agent or a reducing agent/catalyst, continuously stir the reaction under a hydrogen atmosphere at room temperature to 100 ° C, add formaldehyde, and heat up to Stirring at 60 ° C to reflux temperature for a period of time; (2) removing the solvent from the solution to precipitate the product; wherein A is defined in claim 4; R ₁ to R ₂ are defined in claim 1; R is defined in the request Item 1; and W, Q, and n are defined in claim 1. The method of claim 4 or 5, wherein the solvent of the step (1) is N-N-dimethylvinylamine (DMAc) or ethanol (Ethanol). The method of claim 4 or 5, wherein the reducing agent or reducing agent/catalyst of the step (1) is palladium carbon (Pd/C). The method of claim 4, wherein the solvent of the step (2) is Dioxane or Chloroform. The method of claim 4 or 5, wherein the polyfunctional amine or nitro group is a difunctional amine or a nitro group and a hydrazine functional amine or a nitro group. The method of claim 9, wherein the difunctional amine or nitro group is selected from the group consisting of an aromatic amine group or a nitro group, an aromatic amine group or a nitro group having an ether group in the para position, and an aromatic group having an ether group in the meta position. A group consisting of an amine group or a nitro group, a benzene ring/naphthylcycloamino group or a nitro group and an aromatic amine group or a nitro group having a substituent. The method of claim 10, wherein the aromatic amine group or the nitro group having an ether group in the para position is represented by the formula (9), Wherein A and B are each independently a hydrogen atom or an oxygen atom; and Ar is selected from the group consisting of: The Y and Z systems are defined in request item 1. The method of claim 11, wherein the aromatic amine group or the nitro group of the formula (9) is an aromatic amine group or a nitro group (10) oxoazobenzocyclohexane resin The method of claim 10, wherein the aromatic amine group or the nitro group having an ether group is represented by the formula (13), Wherein A and B are defined in request item 11; and Ar is defined in request item 11. The method of claim 13, wherein the aromatic amine group of the formula (2) and the formula (13) or the nitro group is synthesized by the formula (14) oxoazobenzocyclohexane resin The method of claim 10, wherein the benzene ring/naphthylcycloamine or nitro group is represented by the formula (15), A ₂ N-Ar-NB ₂ (15) wherein A and B are defined in claim 11; It is defined in request item 11. The method of claim 15, wherein the benzene ring/naphthalene cyclic amine group or the nitro group is synthesized by the formula (2) and the formula (15) oxynitride benzocyclohexane resin The method of claim 9, wherein the hydrazine functional amino group or nitro group is represented by formula (23), Among them, A, B and C are each independently a hydrogen atom or an oxygen atom. The method of claim 17, wherein the functional group (2) and the formula (23) are a functional amino group or a nitro group (24) oxoazobenzocyclohexane resin.