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CN111057019A - Method for producing 2-(2'-hydroxy 5'-methoxyphenyl)benzotriazole - Google Patents

Method for producing 2-(2'-hydroxy 5'-methoxyphenyl)benzotriazole Download PDF

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CN111057019A
CN111057019A CN201911333135.9A CN201911333135A CN111057019A CN 111057019 A CN111057019 A CN 111057019A CN 201911333135 A CN201911333135 A CN 201911333135A CN 111057019 A CN111057019 A CN 111057019A
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methoxyphenyl
hydroxyl
benzotriazole
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李传碧
刘春玲
王贺
韩爽
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Jilin Normal University
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    • CCHEMISTRY; METALLURGY
    • C07ORGANIC CHEMISTRY
    • C07DHETEROCYCLIC COMPOUNDS
    • C07D249/00Heterocyclic compounds containing five-membered rings having three nitrogen atoms as the only ring hetero atoms
    • C07D249/16Heterocyclic compounds containing five-membered rings having three nitrogen atoms as the only ring hetero atoms condensed with carbocyclic rings or ring systems
    • C07D249/18Benzotriazoles
    • C07D249/20Benzotriazoles with aryl radicals directly attached in position 2
    • CCHEMISTRY; METALLURGY
    • C08ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
    • C08KUse of inorganic or non-macromolecular organic substances as compounding ingredients
    • C08K5/00Use of organic ingredients
    • C08K5/0008Organic ingredients according to more than one of the "one dot" groups of C08K5/01 - C08K5/59
    • C08K5/005Stabilisers against oxidation, heat, light, ozone
    • CCHEMISTRY; METALLURGY
    • C08ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
    • C08KUse of inorganic or non-macromolecular organic substances as compounding ingredients
    • C08K5/00Use of organic ingredients
    • C08K5/16Nitrogen-containing compounds
    • C08K5/34Heterocyclic compounds having nitrogen in the ring
    • C08K5/3467Heterocyclic compounds having nitrogen in the ring having more than two nitrogen atoms in the ring
    • C08K5/3472Five-membered rings
    • C08K5/3475Five-membered rings condensed with carbocyclic rings

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Abstract

本发明是一种苯并三唑类紫外线吸收剂制造方法,更具体的说是一种制造2‑(2’‑羟基5’‑甲氧基苯基)苯并三唑的方法,步骤如下:邻硝基苯胺在无机强酸性、低温条件下,与碱金属亚硝酸盐反应合成重氮盐;在碱性条件下,将对甲氧基苯酚溶解在脂肪族溶剂中,在低温条件下与重氮盐偶合得到偶氮化合物;偶氮化合物在碱性条件下,在还原剂作用下,生产半还原产物;半还原产物在有机溶剂中,在金属还原剂作用下,得到本产品。由于采用上述制造方法,使制造紫外线吸收剂2‑(2’‑羟基5’‑甲氧基苯基)苯并三唑更简单、含量高、产率高、无污染、阻隔率高。

Figure 201911333135

The present invention is a kind of manufacture method of benzotriazole ultraviolet absorber, more specifically a kind of manufacture method of 2-(2'-hydroxyl 5'-methoxyphenyl) benzotriazole, and the steps are as follows: Under the condition of inorganic strong acidity and low temperature, o-nitroaniline reacts with alkali metal nitrite to synthesize diazonium salt; The azo compound is obtained by coupling the nitrogen salt; the azo compound produces a semi-reduced product under the action of a reducing agent under alkaline conditions; the semi-reduced product is obtained in an organic solvent under the action of a metal reducing agent. Due to the above-mentioned production method, the production of the ultraviolet absorber 2-(2'-hydroxy 5'-methoxyphenyl) benzotriazole is simpler, the content is high, the yield is high, no pollution, and the blocking rate is high.

Figure 201911333135

Description

Method for producing 2- (2 '-hydroxy-5' -methoxyphenyl) benzotriazole
Technical Field
The invention relates to a method for preparing benzotriazole ultraviolet absorbent, in particular to a method for preparing 2- (2 '-hydroxy 5' -methoxyphenyl) benzotriazole.
Background
Ultraviolet absorbers, which are the main type of light stabilizers, are substances that selectively absorb ultraviolet light of a fixed wavelength and then undergo energy conversion to release or consume energy as thermal energy or harmless low radiation, and do not harm the human body. The existing ultraviolet absorbent mainly comprises benzophenone absorbent, carboxylic acid absorbent and benzotriazole absorbent. The benzophenone absorbent and the carboxylic acid absorbent have low ultraviolet absorptivity, low barrier rate, easy leaching and short service life of protected materials (such as plastics). The benzotriazole ultraviolet absorbent is a nitrogen-containing heterocyclic compound with excellent performance and capable of absorbing ultraviolet with specific wavelength, and plays an important role in industry, agriculture and manufacturing.
A new benzotriazole ultraviolet absorbent with high absorptivity, high barrier rate and difficult leaching is needed to adapt to industrial application.
Disclosure of Invention
The invention aims to provide a method for preparing 2- (2 '-hydroxy 5' -methoxyphenyl) benzotriazole, which has high absorption rate and high barrier rate and is difficult to leach out.
The technical scheme of the invention is as follows:
a method of making 2- (2 '-hydroxy 5' -methoxyphenyl) benzotriazole comprising the steps of:
a. reacting o-nitroaniline with alkali metal nitrite under the conditions of inorganic strong acid and low temperature to synthesize diazonium salt;
b. under the alkaline condition, p-methoxyphenol is dissolved in an aliphatic solvent and coupled with diazonium salt under the low-temperature condition to obtain an azo compound;
c. the azo compound is used for producing a semi-reduction product under the action of a reducing agent under the alkaline condition;
d. the semi-reduction product is put in organic solvent and under the action of metal reducing agent, so that the product is obtained.
The strong inorganic acid used is hydrochloric acid or sulfuric acid.
The reaction temperature in the a.b step is controlled below 5 ℃.
The alkali metal nitrite used includes sodium nitrite or potassium nitrite.
The alkaline conditions described are the addition of an amount of NaOH, KOH or Ca (OH) to the solvent2And (4) forming.
Aliphatic solvents mentioned include cyclohexane, octane, petroleum ether.
Reducing agents described include inorganic salts: na (Na)2S、NaHS、NH4HS、(NH4)2S and their mixture, the aldehydes include formaldehyde, acetaldehyde, paraformaldehyde, paraldehyde, reducing sugar, and hydrazine.
Metallic reducing agents are described as Zn, Sn, Al, Fe and mixtures thereof.
The organic solvents mentioned are xylene, toluene, benzene.
The molar ratio of the o-nitroaniline to the p-methoxyphenol is 1: 1; the mass ratio of the alkali metal nitrite to the o-nitroaniline is 5-6: 10.
the invention has the beneficial effects that:
1. therefore, the invention discloses a 2- (2 '-hydroxy 5' -methoxyphenyl) benzotriazole ultraviolet absorbent, which can effectively absorb ultraviolet light of 260-400nm and has higher barrier rate (barrier rate 90.1%) compared with other ultraviolet absorbents. The light stabilizer is widely applied to plastics, synthetic rubber, dyes, fibers and the like, and is a high-efficiency light stabilizer.
2. The ultraviolet absorbent has high ultraviolet absorptivity and high blocking rate, is not easy to leach, and has good effect.
Drawings
FIG. 1 is a diagram showing ultraviolet absorption of 2- (2 '-hydroxy-5' -methoxyphenyl) benzotriazole.
Detailed Description
A process for the manufacture of 2- (2 '-hydroxy 5' -methoxyphenyl) benzotriazole, comprising the steps of:
a. reacting o-nitroaniline with alkali metal nitrite under the conditions of inorganic strong acid and low temperature to synthesize diazonium salt;
b. under the alkaline condition, p-methoxyphenol is dissolved in an aliphatic solvent and coupled with diazonium salt under the low-temperature condition to obtain an azo compound;
c. the azo compound is used for producing a semi-reduction product under the action of a reducing agent under the alkaline condition;
d. the semi-reduction product is put in organic solvent and under the action of metal reducing agent, so that the product is obtained.
The strong inorganic acid used is hydrochloric acid or sulfuric acid. The reaction temperature in the a.b step was controlled to 5 ℃ or lower. The alkali metal nitrite used includes sodium nitrite or potassium nitrite. The alkaline conditions described are the addition of an amount of NaOH, KOH or Ca (OH) to the solvent2And (4) forming. Aliphatic solvents mentioned include cyclohexane, octane, petroleum ether. Reducing agents described include inorganic salts: na (Na)2S、NaHS、NH4HS、(NH4)2S and their mixture, the aldehydes include formaldehyde, acetaldehyde, paraformaldehyde, paraldehyde, reducing sugar, and hydrazine. Metallic reducing agents are described as Zn, Sn, Al, Fe and mixtures thereof. The organic solvents mentioned are xylene, toluene, benzene.
Examples
1. a, preparing diazonium salt: adding 10g of o-nitroaniline, 30g of deionized water and 28ml of hydrochloric acid (33%) into a 100ml three-necked bottle provided with a stirrer and a thermometer, stirring, heating to 45 ℃, keeping the temperature for 1 hour, cooling to 0 ℃, adding 5.5g of sodium nitrite, keeping the temperature and stirring for 3 hours to obtain diazonium salt for later use.
b preparation of azo Compound: 100ml of cyclohexane and 10g of p-methoxyphenol were added to a 500ml three-necked flask equipped with a stirrer and a thermometer, and after dissolution by stirring at room temperature, NaOH6g was added, stirring was continued for 1 hour, the temperature was lowered to 0 ℃ and the diazonium salt to be used was added to the three-necked flask within 0.5 hour. 21g of a red azo compound was obtained.
c, half reduction reaction: into a 1000ml three-necked flask equipped with a stirrer and a thermometer were charged the above azo compound, Ca (OH)28g,NH4HS16g, and deionized water 280 ml. Stirring, heating to 50 deg.C, reacting for 1 hr to obtain yellow semi-reduced product 19 g.
d, reduction reaction: 20g of half-reduced product, 280ml of benzene and 10g of Fe powder are respectively added into a 500ml three-necked bottle provided with a stirrer and a thermometer, stirred and heated to 60 ℃, and reacted for 1 hour to obtain 15g of white product with the content of 99.3 percent.
2. a, preparing diazonium salt: adding 10g of o-nitroaniline, 30g of deionized water and 6ml of sulfuric acid (93%) into a 100ml three-necked bottle provided with a stirrer and a thermometer, stirring, heating to 45 ℃, keeping the temperature for 1 hour, cooling to 0 ℃, adding 5g of potassium nitrite, keeping the temperature and stirring for 3 hours to obtain diazonium salt for later use.
b preparation of azo Compound: in a 500ml three-necked flask equipped with a stirrer and a thermometer, 100ml of cyclohexane and 10g of p-methoxyphenol were charged, and after dissolving the mixture by stirring at room temperature, Ca (OH) was added26g, stirring is continued for 1 hour, the temperature is reduced to 0 ℃, and the diazonium salt for standby is added into a three-necked bottle within 0.5 hour. 22.4g of a red azo compound was obtained.
c, half reduction reaction: into a 1000ml three-necked flask equipped with a stirrer and a thermometer were charged the above azo compound, Ca (OH)28g, 10g of paraformaldehyde and 270ml of deionized water. Stirring, heating to 50 deg.C, reacting for 1 hr to obtain yellow semi-reduced product 20.8 g.
d, reduction reaction: 21g of semi-reduction product, 300ml of benzene, 8g of Sn powder and 1.5g of hydrazine are respectively added into a 500ml three-necked bottle provided with a stirrer and a thermometer, and the mixture is stirred and heated to 60 ℃ to react for 1 hour to obtain 17g of white product with the content of 98.9 percent.
3. a, preparing diazonium salt: adding 10g of o-nitroaniline, 30g of deionized water and 6ml of hydrochloric acid (93%) into a 100ml three-necked bottle provided with a stirrer and a thermometer, stirring, heating to 45 ℃, keeping the temperature for 1 hour, cooling to 0 ℃, adding 6g of sodium nitrite, keeping the temperature and stirring for 3 hours to obtain diazonium salt for later use.
b preparation of azo Compound: 50ml of cyclohexane, 30ml of petroleum ether and 10g of p-methoxyphenol are added into a 500ml three-necked flask equipped with a stirrer and a thermometer, after stirring and dissolving at room temperature, 6g of KOH is added, stirring is continued for 1 hour, the temperature is reduced to 0 ℃, and the diazonium salt for standby is added into the three-necked flask within 0.5 hour. 23.4g of a red azo compound was obtained.
c, half reduction reaction: into a 1000ml three-necked flask equipped with a stirrer and a thermometer, the above azo compound, Ca (OH)28g of hydrazine, 18g of hydrazine,280ml of deionized water. Stirring, heating to 50 deg.C, reacting for 1 hr to obtain 21.6g of yellow semi-reduced product.
d, reduction reaction: 20g of half-reduced product, 300ml of benzene, 5.5g of Sn powder and 1.5g of Zn powder are respectively added into a 500ml three-necked bottle provided with a stirrer and a thermometer, and the mixture is stirred and heated to 60 ℃ to react for 1 hour to obtain 16.5g of white product with the content of 99.2 percent.
The absorption principle of benzotriazole ultraviolet absorber
The benzotriazole ultraviolet absorbent can selectively absorb ultraviolet with the wavelength of 290-400nm, and a hydrogen atom on an ortho-hydroxyl and a nitrogen atom on benzotriazole generate a resonance effect. Researches show that the benzotriazole ultraviolet absorbers exist in a phenolic structure, and the light resistance of the benzotriazole ultraviolet absorbers is because the benzotriazole ultraviolet absorbers can perform reversible tautomeric conversion through hydrogen bond chelating rings in molecules, and after ultraviolet light is absorbed, protons can be rapidly transferred to nitrogen atoms to form tautomers, so that excitation energy is effectively converted, and redundant energy is rapidly converted into heat energy to be released, so that the absorbed energy is consumed, and the ultraviolet absorbers return to the ground state. Thus, the ultraviolet energy is converted into heat to be discharged, and the damage of the ultraviolet to the plastic products is avoided.
The synthesis process of the invention is divided into three steps: firstly, synthesizing diazonium salt; secondly, synthesizing an azo compound; and thirdly, reducing the azo compound. Other benzotriazole reductions require two steps (semi-reduction, reduction), thus reducing the synthesis steps.
The absorption intensity peak is 200nm-52nm, the absorption intensity is above 75%, the ultraviolet absorbent synthesized by the patent has wide absorption range and large absorption intensity. The absorption range is 200nm-520nm, and the absorption intensity is more than 75%.
The product synthesis route is as follows:
Figure BDA0002328823470000031

Claims (10)

1.一种制造2-(2’-羟基5’-甲氧基苯基)苯并三唑的方法,按以下步骤进行:1. a method for making 2-(2'-hydroxyl 5'-methoxyphenyl) benzotriazole, is carried out according to the following steps: a、邻硝基苯胺在无机强酸性、低温条件下,与碱金属亚硝酸盐反应合成重氮盐;a, o-nitroaniline reacts with alkali metal nitrite to synthesize diazonium salt under inorganic strong acidity and low temperature conditions; b、在碱性条件下,将对甲氧基苯酚溶解在脂肪族溶剂中,在低温条件下与重氮盐偶合得到偶氮化合物;b. Under alkaline conditions, p-methoxyphenol is dissolved in an aliphatic solvent, and the azo compound is obtained by coupling with a diazonium salt under low temperature conditions; c、偶氮化合物在碱性条件下,在还原剂作用下,生产半还原产物;c. The azo compound produces semi-reduced products under the action of a reducing agent under alkaline conditions; d、半还原产物在有机溶剂中,在金属还原剂作用下,得到本产品。d. The semi-reduced product is obtained in an organic solvent under the action of a metal reducing agent. 2.根据权利要求1所述的一种制造2-(2’-羟基5’-甲氧基苯基)苯并三唑的方法,其特征在于:所使用的无机强酸有盐酸或硫酸。2. a kind of method of making 2-(2'-hydroxyl 5'-methoxyphenyl) benzotriazole according to claim 1 is characterized in that: the inorganic strong acid used has hydrochloric acid or sulfuric acid. 3.根据权利要求1所述的一种制造2-(2’-羟基5’-甲氧基苯基)苯并三唑的方法,其特征在于:所述a.b步骤中反应温度控制在5℃以下。3. a kind of method of making 2-(2'-hydroxyl 5'-methoxyphenyl) benzotriazole according to claim 1, is characterized in that: in described a.b step, reaction temperature is controlled at 5 ℃ the following. 4.根据权利要求1所述的一种制造2-(2’-羟基5’-甲氧基苯基)苯并三唑的方法,其特征在于:所使用的碱金属亚硝酸盐包括亚硝酸钠或亚硝酸钾。4. a kind of method of making 2-(2'-hydroxyl 5'-methoxyphenyl) benzotriazole according to claim 1 is characterized in that: the alkali metal nitrite used comprises nitrous acid sodium or potassium nitrite. 5.根据权利要求1所述的一种制造2-(2’-羟基5’-甲氧基苯基)苯并三唑的方法,其特征在于:所叙述的的碱性条件是在溶剂中加入一定量的NaOH、KOH或Ca(OH)2形成的。5. a kind of method of making 2-(2'-hydroxyl 5'-methoxyphenyl) benzotriazole according to claim 1, is characterized in that: described basic condition is in solvent It is formed by adding a certain amount of NaOH, KOH or Ca(OH) 2 . 6.根据权利要求1所述的一种制造2-(2’-羟基5’-甲氧基苯基)苯并三唑的方法,其特征在于:所叙述的脂肪族溶剂包括环己烷、辛烷、石油醚。6. a kind of method of making 2-(2'-hydroxyl 5'-methoxyphenyl) benzotriazole according to claim 1, is characterized in that: described aliphatic solvent comprises cyclohexane, Octane, petroleum ether. 7.根据权利要求1所述的一种制造2-(2’-羟基5’-甲氧基苯基)苯并三唑的方法,其特征在于:所叙述的还原剂包括无机盐类:Na2S、NaHS、NH4HS、(NH4)2S、及其混合物,醛类包括甲醛、乙醛、多聚甲醛、三聚乙醛、还原性糖,肼。7. a kind of method of making 2-(2'-hydroxyl 5'-methoxyphenyl) benzotriazole according to claim 1 is characterized in that: described reducing agent comprises inorganic salts: Na 2S, NaHS , NH4HS , ( NH4 ) 2S, and mixtures thereof, aldehydes include formaldehyde, acetaldehyde, paraformaldehyde, paraldehyde, reducing sugars, hydrazine. 8.根据权利要求1所述的一种制造2-(2’-羟基5’-甲氧基苯基)苯并三唑的方法,其特征在于:所叙述的金属还原剂有Zn、Sn、Al、Fe及其混合物。8. a kind of method of making 2-(2'-hydroxyl 5'-methoxyphenyl) benzotriazole according to claim 1, is characterized in that: described metal reducing agent has Zn, Sn, Al, Fe and their mixtures. 9.根据权利要求1所述的一种制造2-(2’-羟基5’-甲氧基苯基)苯并三唑的方法,其特征在于:所叙述的有机溶剂有二甲苯、甲苯、苯。9. a kind of method of making 2-(2'-hydroxyl 5'-methoxyphenyl) benzotriazole according to claim 1, is characterized in that: described organic solvent has xylene, toluene, benzene. 10.根据权利要求1所述的一种制造2-(2’-羟基5’-甲氧基苯基)苯并三唑的方法,其特征在于:所述邻硝基苯胺和对甲氧基苯酚摩尔比1:1;碱金属亚硝酸盐和邻硝基苯胺质量比值为5-6:10。10. a kind of method of making 2-(2'-hydroxyl 5'-methoxyphenyl) benzotriazole according to claim 1, is characterized in that: described o-nitroaniline and p-methoxyl group The molar ratio of phenol is 1:1; the mass ratio of alkali metal nitrite and o-nitroaniline is 5-6:10.
CN201911333135.9A 2019-12-20 2019-12-20 Method for producing 2-(2'-hydroxy 5'-methoxyphenyl)benzotriazole Pending CN111057019A (en)

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Citations (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPS52113974A (en) * 1976-03-19 1977-09-24 Kawaken Fine Chem Co Ltd Synthesis of benzotriazole derivatives
CN102295613A (en) * 2010-06-25 2011-12-28 吉林师范大学 Method for preparing 2-(2'-hydroxyl 5'-tert-octyl phenyl)benzotriazole
CN108026054A (en) * 2015-07-07 2018-05-11 3M创新有限公司 substituted benzotriazole phenol
CN109073781A (en) * 2016-04-21 2018-12-21 依视路国际公司 The optical material of benzotriazole UV absorbers comprising red shift

Patent Citations (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPS52113974A (en) * 1976-03-19 1977-09-24 Kawaken Fine Chem Co Ltd Synthesis of benzotriazole derivatives
CN102295613A (en) * 2010-06-25 2011-12-28 吉林师范大学 Method for preparing 2-(2'-hydroxyl 5'-tert-octyl phenyl)benzotriazole
CN108026054A (en) * 2015-07-07 2018-05-11 3M创新有限公司 substituted benzotriazole phenol
CN109073781A (en) * 2016-04-21 2018-12-21 依视路国际公司 The optical material of benzotriazole UV absorbers comprising red shift

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