JP2702251B2 - Method for producing 1- (3-aminophenyl) -1- (hydroxyphenyl) ethane derivative - Google Patents

Description

The present invention relates to a method for producing a 1- (3-aminophenyl) -1- (hydroxyphenyl) ethane derivative (hereinafter abbreviated as AHE).

This AHE is useful as a raw material for epoxy resins and maleimide compounds, and can also be used as a curing agent for epoxy resins, bismaleimide compounds and isocyanate compounds.

[Conventional technology]

As a compound in which an aniline and a phenol are linked as in the AHE of the present invention, 2- (aminophenyl) -2-
(Hydroxyphenyl) propane is known. This compound is prepared from p-isopropenylphenol and anilines (JP-B-41-17645), and is prepared from isophenylaniline and phenols (JP-A-62-1149).
42).

[Problems to be solved by the invention]

In the above-mentioned compound production method, since the vinyl compound as the raw material has a reactive double bond, there is a problem that a side reaction such as doubling or cyclization is involved in self-polymerization or condensation reaction during storage. On the other hand, a structure in which a phenol and an aniline are bonded to the 2-position of propane is easily cleaved by heat or the like to produce various complicated compounds, and thus its use is restricted depending on the application.

[Problems to be solved by the invention]

Recent heat-resistant resin materials are required to withstand instantaneous impacts such as stress concentration as well as heat resistance, especially when used as a matrix resin such as carbon fiber or glass fiber. As a criterion, the elongation of the matrix resin is important. In order to impart such flexibility, a method of introducing a partially broken structure into the structure of the resin is generally used. Therefore, a meta-based compound is desired as a resin raw material.

[Means for solving the problem]

The present inventors have conducted intensive studies in order to solve the above-mentioned object, and as a result, have come to inertia the present invention.

That is, the present invention relates to 3-amino-α-methylbenzyl alcohol and formula (I) (Wherein, R ₁ and R ₂ represent a hydrogen atom, an alkyl group having 1 to 9 carbon atoms, a cycloalkyl group, an aryl group, or an aralkyl group, which may be the same or different. N is an integer of 1 or 2) Wherein the phenol represented by the formula (II) is reacted in the presence of an acid catalyst. (In the formula, R ₁ , R ₂ and n are the same as those in the formula (I).) A method for producing a 1- (3-aminophenyl) -1- (hydroxyphenyl) ethane derivative represented by the following formula:

The AHE obtained by the method of the present invention is a conventional 2
Thermal stability is better than-(aminophenyl) -2- (hydroxyphenyl) propane. Further, since the amino group is substituted at the meta position, it is useful as a heat-resistant resin material for composite materials.

The method of the present invention will be described specifically.
Amino-α-methylbenzyl alcohol can be produced by reducing 3-nitroacetophenone obtained by nitrating acetophenone.

Examples of the phenol represented by the formula (I) include phenol, o-cresol, m-cresol, p-cresol, o-ethylphenol, p-ethylphenol, on-propylphenol, o-isopropylphenol, and m-cresol. -Isopropylphenol, pn-propylphenol, o-sec-butylphenol, o-ter
t-butylphenol, p-tert-butylphenol,
p-tert-amylphenol, o-phenylphenol, p-phenylphenol, o-cyclohexylphenol, p-cyclohexylphenol, p-tert-octylphenol, p-nonylphenol, o-cumylphenol, p-cumylphenol, 2 , 4-xylenol, 2,6-xylenol, 2,6-tert-butylphenol, 2-methyl-4-tert-butylphenol, 2-methyl-4-phenylphenol, 2,6-dicumylphenol, resorcinol, catechol, Hydroquinone, 2-
Examples include, but are not limited to, methylresorcinol. Of the above, industrially preferred are phenol, cresols and xylenols.

The amount of these phenols to be used is an excess amount based on 3-amino-α-methylbenzyl alcohol, but is specifically 1 to 20 mole ratio, preferably 1.5 to 10 mole ratio.

In the method of the present invention, the condensation reaction is performed in the presence of an acid catalyst. Examples of the acid catalyst include mineral acids such as hydrochloric acid, sulfuric acid, and phosphoric acid, organic sulfonic acids such as methanesulfonic acid, p-toluenesulfonic acid, and xylenesulfonic acid, aluminum chloride, tin chloride, boron trifluoride, iron chloride, and chloride. Lewis acids such as zinc, heteropoly acids, super strong acids such as trifluoromethanesulfonic acid, ordinary cation-type ion exchange resins,
A perfluoroalkanesulfonic acid-type ion exchange resin, a natural zeolite catalyst such as acid clay, and a synthetic zeolite catalyst such as Y-type zeolite, L-type zeolite, mordenite, and ferrilite can be used.

Among them, preferred are solid acid catalysts such as hydrochloric acid, p-toluenesulfonic acid, acid clay, and synthetic zeolites. The amount of these catalysts used is selected arbitrarily from the amount of the catalyst to the large excess with respect to the raw material, but in consideration of economy, 0.5 to 50% by weight, preferably about 3 to 20% by weight is frequently used. You.

In the method of the present invention, the reaction is usually carried out without a solvent, but there is no problem even if a solvent inert to the reaction is used. As the solvent, aromatic hydrocarbons such as toluene and xylene, ethers such as 2-ethoxyethanol and diethylene glycol dimethyl ether, and chlorobenzene can be used.

The reaction temperature varies slightly depending on the type of catalyst, but is usually 80
A range of 200200 ° C., especially 100-180 ° C., is selected. The reaction time is preferably 1 to 20 hours, particularly preferably 2 to 8 hours.

In the reaction, the raw material and the catalyst may be charged at once and the temperature may be raised as it is to carry out the reaction, or the catalyst or one of the raw materials may be charged from the middle. The progress of the reaction can be monitored by high performance liquid chromatography or the like.

Post-treatment after completion of the reaction is generally performed by cooling, filtering or neutralizing the acid to remove the catalyst component, and then washing and separating the solution with water, and a method of isolating the target product from the reaction solution from which the catalyst has been removed. After removing the unreacted raw materials and concentrating the reaction solution, a method of crystallizing using a general recrystallization solvent, a method of crystallizing as a mineral salt such as a hydrochloride, or a method of distilling the target substance by distillation Any of the methods of obtaining can be selected.

1- (3-aminophenyl) -1- (4-hydroxyphenyl) ethane, 1- (3-aminophenyl) -1- (2-hydroxyphenyl) ethane, 1- (3 -Aminophenyl) -1
-(3-methyl-4-hydroxyphenyl) ethane, 1
-(3-aminophenyl) -1- (2-hydroxy-3
-Methylphenyl) ethane, 1- (3-aminophenyl) -1- (2-hydroxy-5-methylphenyl) ethane, 1- (3-aminophenyl) -1- (2-hydroxy-4-methylphenyl) Ethane, 1- (3-aminophenyl) -1- (2-hydroxy-6-methylphenyl) ethane, 1- (3-aminophenyl) -1- (3,5
-Dimethyl-4-hydroxyphenyl) ethane, 1-
(3-aminophenyl) -1- (3,5-dimethyl-4-
Hydroxyphenyl) ethane, 1- (3-aminophenyl) -1- (2-hydroxy-5-methylphenyl) ethane, 1- (3-aminophenyl) -1- (3-isopropyl-4-hydroxyphenyl) ethane , 1- (3-
Aminophenyl) -1- (2-hydroxy-5-tert-
Butylphenyl) ethane, 1- (3-aminophenyl)
-1- (3-cyclohexyl-4-hydroxyphenyl) ethane, 1- (3-aminophenyl) -1- (3-
Phenyl-4-hydroxyphenyl) ethane, 1- (3
-Aminophenyl) -1- (2,4-dihydroxyphenyl) ethane, 1- (3-aminophenyl) -1- (2,5
-Dihydroxyphenyl) ethane, 1- (3-aminophenyl) -1- (2,4-dihydroxy-3-methylphenyl) ethane and the like. Also, these AHEs are
In some cases, it is obtained as a mixture of three isomers.

 Hereinafter, the present invention will be described in more detail with reference to examples.

〔Example〕

Example 1 3-Amino-α-methylbenzyl alcohol was placed in a reactor
27.5 g (0.2 mol), 94 g (1 mol) of phenol, and 10 g of galeonite (trade name, manufactured by Mizusawa Chemical) as a catalyst were charged, and the temperature was raised while stirring. On the way, while the distilling water was being removed from the system, the system was stopped when the temperature reached 160 ° C., and then ripening was performed at 160 to 170 ° C. for 8 hours. After the reaction, the mixture was cooled to 80 ° C., and filtered to remove the catalyst. Unreacted phenol was recovered from the filtrate by vacuum distillation and further distilled at a boiling point of 171 to 175 ° C / 1 mmHg to obtain the desired product. 37.6 g (88.3% yield) of a colorless and transparent oil was obtained. This was analyzed by high performance liquid chromatography (HPLC), and as a result, it had the following composition.

HPLC analysis result (Areac%) 1- (3-aminophenyl) -1- (4-hydroxyphenyl) ethane 51.5% 1- (3-aminophenyl) -1- (2-hydroxyphenyl) ethane 47.7% Other 0.8% Example 2 3-Amino-α-methylbenzyl alcohol in a reactor
27.5 g (0.2 mol), 48.8 g (0.4 mol) of 2,6-xylenol, and 21 g (0.2 mol) of a 35% hydrochloric acid aqueous solution as a catalyst were charged, and the temperature was raised to 120 ° C. with stirring. Thereafter, aging was carried out at the same temperature for 5 hours to complete the reaction.

After adding 200 ml of toluene to the reaction solution and slowly cooling, crystals were precipitated. This is 1- (3-aminophenyl) -1-
It was the hydrochloride of (4-hydroxy-3,5-dimethylphenyl) ethane, which was filtered to give crude crystals. This was recrystallized from a 15% saline solution to obtain crystals of the purified hydrochloride.
After dissolving in 500 ml of water, neutralize with ammonia water,
A white powdery precipitate was deposited. This is filtered and dried to obtain 1
-(3-Aminophenyl) -1- (4-hydroxy-3,
39.6 g (82.5% yield) of 5-dimethylphenyl) ethane was obtained.

The melting point was 110-111 ° C and the result of elemental analysis was as follows.

Elemental analysis value Calculated value of CHN (%) 79.5 7.95 5.8 Measured value (%) 79.2 8.05 5.7 [Effect of the Invention] As described above, using inexpensive raw materials and using a simple method to obtain useful meta-positions AHE having an amino group can be produced in high yield.

──────────────────────────────────────────────────続 き Continuation of the front page (51) Int.Cl. ⁶ Identification number Agency reference number FI Technical display location C07B 61/00 300 C07B 61/00 300

Claims (1)

(57) [Claims] (1) 3-amino-α-methylbenzyl alcohol and a compound of the formula (I) (Wherein, R ₁ and R ₂ represent a hydrogen atom, an alkyl group having 1 to 9 carbon atoms, a cycloalkyl group, an aryl group, or an aralkyl group, which may be the same or different. N is an integer of 1 or 2) Wherein the phenol represented by the formula (II) is reacted in the presence of an acid catalyst. (Wherein, R ₁ and R ₂ represent a hydrogen atom, an alkyl group having 1 to 9 carbon atoms, a cycloalkyl group, an aryl group, or an aralkyl group, which may be the same or different. N is an integer of 1 or 2) A method for producing a 1- (3-aminophenyl) -1- (hydroxyphenyl) ethane derivative represented by the formula: