JPH04187679A - Preparation of 2-(2-hydroxyphenyl)benzotriazole derivative - Google Patents

Abstract

PURPOSE:To prepare the subject compound useful as a weather resistance- improving agent for organic materials by reacting a (hydroxyalkylphenyl) benzotriazole with an alpha-olefin in the presence of methane sulfonic acid at a high temperature. CONSTITUTION:A 2-(2-hydroxy-5-alkylphenyl)benzotriazole [e.g. 2-(2-hydroxy-5- isopropylphenyl)benzotriazole] of formula I (R1 is 3-8C alkyl; X is H, Cl) [e.g. 2-(2-hydroxy-5isopropylphenyl)benzotriazole] is reacted with an alpha-8-12C olefin in the presence of a methane sulfonic acid at temperature of >=150 deg.C, preferably 160-190 deg.C, to prepare the objective 2-(2-hydroxy-3,5-dialkylphenyl)benzotriazole of formula II (R2 is 8-12C alkyl). After the reaction is finished, the reaction solution is allowed to stand. The lover layer containing the major part of the sulfonic acid is preferably separated, and the remaining upper layer is washed with water and subsequently purified.

Description

[Detailed Description of the Invention] <Industrial Application Field> The present invention is a material that changes the structure of 2-(2-hydroxyphenyl)benzotriazole, which is well known as a material that is added to organic materials to improve weather resistance. It is about improving performance.

2-(2-hydroxyphenyl)benzotriazole, which is the structural base of the present invention, has the effect of absorbing ultraviolet rays and converting them into harmless wavelengths when added to an organic polymer compound. When added to organic materials such as synthetic resins, this property has the great effect of making light stable. For this reason, it is widely used in various organic polymer compounds such as polyolefin resins, polyester resins, vinyl chloride resins, ABS, AS, and EVA.

<Prior art> Due to its excellent properties, 2-(2-hydroxyphenyl)benzotriazole has many known compounds as its derivatives, but most of them have poor solubility in organic solvents and have comparatively low melting points. Due to its high molecular weight, it has poor compatibility with large organic resins such as polyolefins, and has the disadvantage that it precipitates when used at high concentrations. Furthermore, there are problems such as sublimation and volatilization, which limits its use. In recent years, the field of application of synthetic resins has expanded, and in many cases they are formed into membranes such as films and paints, and are used under harsher conditions than before, such as high processing temperatures.

Therefore, there is a need for a device that can be used stably under such conditions.

The present inventors have proposed a method for solving the above-mentioned problems by introducing highly organic substituents into organic polymeric compounds in order to increase their compatibility, thereby lowering the melting point and at the same time making them highly soluble in organic solvents. The present inventors investigated methods for obtaining the new 2-(2-hydroxyphenyl)benzotriazole rust conductor in an economically advantageous manner.

The following are known methods for producing polymers having a 2-(2-hydroxyphenyl)benzotriazole structure.

JP-A-62-63575, JP-A-62-63576, and JP-A-55-7292 are 2-(2-hydroxyphenyl)
We have proposed a compound with a cumyl group introduced into the benzotriazole structure.This higher molecular weight suppresses sublimation and evaporation at high temperatures, improves processing stability and product weather resistance, but many of them There remain problems in use, such as a high melting point and insufficient compatibility.

In USP 3,766,205 and EPOO 57,160, an acrylic acid group is introduced at the 5-position of the phenyl group in a 2-(2-hydroxyphenyl)benzotriazole skeleton, and this is esterified to obtain a high molecular weight, low melting point product. Japanese Patent Application Publication No. 64-71863, Japanese Patent Application Publication No. 1989-1. -2033 to 2-(2
-Hydroxy5-methylphenyl)benzotriazole is alkylated with an alpha olefin having 8 to 16 carbon atoms using sulfonic acid as a catalyst to obtain a compound intended for enhanced performance.

These known products have complicated manufacturing and reaction steps, and there is still much room for improvement from an economical standpoint.

<Problem to be solved by the invention> The present inventors have discovered that 2-(2-hydroxyphenyl) in the skeleton
As a result of our search for a structure that has penzotrisol, has excellent compatibility with solvents, has high evaporation properties, is weather resistant, and is easy to use, we found that - bottom (If), where X is hydrogen. , represents a chlorine atom, R+ represents an alkyl group having 3 to 8 carbon atoms, and this alkyl group may be branched.

R2 is an alkyl group having 8 to 12 carbon atoms, and R2 may be branched. It is a mixture of two or more structures.

The structure has superior performance compared to conventional ones,
Moreover, they have discovered a method that can be produced industrially advantageously.

2-(2-hydroxy-5-alkylphenyl)benzotriazoles represented by the general formula (1) (where X represents hydrogen or a chlorine atom, RI represents an alkyl group having 3 to 8 carbon atoms, and The alkyl group may be branched.) to-bottom% formula% where 7 is represented by a carbon number of 8 to 12, by reacting with an alpha olefin of the general formula (It) where X is Represents hydrogen or chlorine atom, R1 has 3 carbon atoms
represents an alkyl group of 8 to 8, and this alkyl group may be branched. R2 represents an alkyl group having 8 to 12 carbon atoms, and this alkyl group may be branched.

The present invention relates to the mN method for 2-(2-hydroxy-3,5-dialkylphenyl)benzotriazole represented by mN.

[Means for solving 11 problems] Next, the present invention will be explained in more detail.

A compound represented by the general formula (1) that can be used in the present invention is the general formula (1), where X is hydrogen or a chlorine atom, and R3 has 3 carbon atoms.
to 8 alkyl groups, which may be branched.

2-(2-hydroxy-5-alkylphenyl)benzotriazole represented by: 2-(2-hydroxy-5-isopropylphenyl)benzotriazole, 5-chloro-2-(hydroxy-5-isopropylphenyl)benzo Triazole, 2-hydroxy-5-
terbutylphenyl)benzotriazole, 2-(2
-Hydroxy-5-teroctylphenyl)benzotriazole is particularly preferably used.6 The catalyst used in the reaction, methanesulfonic acid, is used in anhydrous form. The amount to be used is preferably about the same mole relative to 2-(2-hydroxyl-5-alkylphenyl)hensitriazole.

Since the anhydrous methanesulfonic acid used here is relatively expensive, it is advantageous to recover and reuse it.In the present invention, after the reaction is completed, it is allowed to stand and is separated into the lower layer as a colored liquid. The methanesulfonic acid layer is separated as it is without diluting it with water and used as a catalyst in the next reaction.

The methanesulfonic acid layer of this black liquid contains the raw material 2-(2
-Hydroxy-5-alkylphenylbenzotriazole contains almost no alkylated reaction product.The result of recovering, reusing, and reacting in this way only replenishes L that is physically destroyed. When the reaction was carried out using the first new catalyst, good results were obtained without any problems.

The alpha olefin having 8 to 12 carbon atoms may have a linear or branched alkyl group, and may be a mixture of these. The amount used is raw material 2-
(2-hydroxy-5-alkylphenyl)benzotriazole is preferably used in an amount of 2 to 3 moles, and a larger amount can be used and recovered after the reaction.

For the reaction, it is best to heat and melt methanesulfonic acid and the raw material 2-(2-hydroxy-5-alkyl)benzotriazole, and then add the alpha olefin dropwise into this mixture. It is best to heat the mixture to a temperature of 100 mL.If the alpha olefin is added dropwise while stirring, it will generate heat, so it is better to add the olefin continuously over 11 minutes.

The heating is adjusted to maintain a temperature of 160 to 190°C from the time the dropwise addition begins. Equilibrium is reached in about 8 hours, so the reaction is terminated.

The reaction is preferably carried out in a nitrogen stream to prevent unnecessary coloration.

Next, the present invention will be explained in detail with reference to Examples.

In the examples, 1 part refers to the weight part unless otherwise specified.

Example 1゜20 equipped with a counterflow condenser, stirrer, dropping funnel, and thermometer
Add 240 parts of methanesulfonic anhydride to a reactor containing 00S parts.
．． 3 parts, 2-(2-hy-1-roxy-5-isopropylphenyl)benzo-1-lyazole (mp 85, 6
-86, 1°C) 632.2 parts and heated to 150% in an oil bath.
Heat and stir to ℃.

While nitrogen gas was slightly passed through the reactor, 842 parts of 1-dodecene (trade name: Dodecene-1: Sanni Kasei) was added dropwise over a period of 5 hours. The enthusiasm for this development can be seen.

The temperature of the contents was maintained at 180 parts at 5°C and reacted.

This T&! When the stirring is stopped and the mixture is allowed to stand still, the liquid will separate into two layers, and the black layer at the bottom will be separated.

The oil layer is stirred and washed using 500 parts of 80"C hot water. At this time, in order to improve the liquid separation, 30 parts of toluene
Dilute with 0 parts. After repeating this washing once again, the dehydration process begins.

Attach an azeotropic dehydrator, stir and heat, and extract water in the form of toluene-water. When the water was completely dehydrated, 100 parts of white clay was added, followed by another 111 parts.

After countercurrent heating and hot filtration, a light brown oil containing the reaction product is obtained. Add 200 parts of 80% ayuic acid to this oil and heat it to 100°C to extract colored impurities. The reaction product thus obtained is subjected to vacuum distillation and loaded.

Distillation was carried out using a rectification column at 0.15 mmHg, bp, 1
The fractions at 95-220°C were collected.

921 parts (yield 87.5%) product UVλ1. x is 31
0□,,341. ,, (chloroform).

Example 1 was placed in a reactor equipped with an actual k N 2° 2000 parts by volume, a backflow condenser, a stirrer, 1 dropping funnel, and a thermometer. 230 parts of recovered methanesulfone 11 and new methanesulfone!
2-(2-hydroxy-5-isopropylphenyl)benzotriazole (m
p, 85.6-86.1°C) 632.2 parts were charged.
The mixture was stirred and heated to 150° C. in an oil bath, and 842 parts of dodecene-1 was added dropwise over 5 hours while nitrogen gas was supplied weakly.

1 During this period, the reaction temperature was kept at 5° C. for 180 parts. When dodecene-1 was added dropwise, the temperature of the contents rose due to heat generation, so the reaction was carried out while controlling the heating.

After reacting at this temperature for an additional 2 hours, the mixture was allowed to cool and when left to stand, the mixture separated into two layers, so the lower layer, a black liquid containing methanesulfonic acid, was separated.

The oil layer is diluted with 300 parts of toluene and then washed with 80°C warm water and agitation. Washed with warm water twice and then dehydrated. After complete dehydration, clay treatment and formic acid extraction f141. After doing this, it was distilled under reduced pressure.

Fraction 9 from 195°C to 224°C at 0.2 m m Hg
Obtained 15 copies.

Example 3 1000S volume unit backflow cooler if! Stirrer, dropping funnel,
Add 96% of methanesulfonic anhydride to a reactor equipped with a thermometer.
part, 2-(2-hydroxy-5-teroctylphenyl)benzotriazole (mp, 1.04,5-10
5.2°C) 323.4 parts were added and stirred at 150°C with oil detergent. Octene-1 (Mitsubishi Kasei) 28 in nitrogen stream
Add 0 parts while being careful not to generate heat 6. Set the reaction temperature to 170~
The reaction was carried out for 10 hours while maintaining the temperature at 180°C.

Example 1. While recovering methanesulfonic acid through static separation using the same method as in , the oil component was washed with hot water, dehydrated, and decolorized.

345 parts of a fraction (transparent pale yellow) with a boiling point of 200-225°C at 0.15-0.2 mmHg were obtained. This product has a maximum absorption wavelength in the ultraviolet region of λ332, λ302, 5. (chloroform).

Example 4- Example 3. In Example 3, 10 parts of new methanesulfonic acid was used in place of 96 parts of methanesulfonic acid in the previously separated and recovered methanesulfonic acid under the reaction conditions of Example 3. The reaction and post-treatment were carried out in the same manner as above. 0.15-0.2 mm
348 parts of a Hg boiling point of 202-225° C. were obtained.

Example 5゜Example 3. 2-(2-hydroxy-5-ter
5-chloro-2(2-hydroxy-5-isopropylphenyl)benzotriazole (mp, 102.4 parts) instead of 323.4 parts of octylphenyl)benzotriazole.
Same recipe 1 except that 288 parts (4-103.0℃) were used.
The reaction was carried out under the following conditions. After purification in the same manner, vacuum distillation was performed to obtain 300 parts of pale yellow oil.

Claims (3)

[Claims] (1) 2-(2-hydroxy-5-alkylphenyl)benzotriazole represented by the general formula (I) ▲ Numerical formulas, chemical formulas, tables, etc. are available ▼ Here, R_1 represents an alkyl group having 3 to 8 carbon atoms. ,
This alkyl group may be branched. X represents a hydrogen or chlorine atom. General formula (II) characterized by reacting an α-olefin having 8 to 12 carbon atoms in the presence of methanesulfonic acid at a temperature of 150°C or higher ▲There are mathematical formulas, chemical formulas, tables, etc.▼ Here, R_1 is carbon represents an alkyl group of numbers 3 to 8,
This alkyl group may be branched. R_
2 represents an alkyl group having 8 to 12 carbon atoms, and may be branched. X represents a hydrogen or chlorine atom. A method for producing 2-(2-hydroxy-3,5-dialkylphenyl)benzotriazole represented by: (2) The compound represented by general formula (II) according to claim 1, characterized in that after the completion of the reaction, after the reaction is completed, a layer containing a large amount of sulfonic acid is separated into a lower layer by being allowed to stand, and then the upper layer is washed with water and purified. Ru2
-Production method of (2-hydroxy-3,5-dialkyl phenyl)benzotriazole (3) The layer containing a large amount of methanesulfonic acid separated in claim 2 is used in the same manner as methanesulfonic acid in the method of claim 1.
- A method for producing (2-hydroxy-3,5-dialkyl phenyl)benzotriazole.