CN102796053A - Preparation method of benzotriazole photostabilizer - Google Patents
Preparation method of benzotriazole photostabilizer Download PDFInfo
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- CN102796053A CN102796053A CN201210252357XA CN201210252357A CN102796053A CN 102796053 A CN102796053 A CN 102796053A CN 201210252357X A CN201210252357X A CN 201210252357XA CN 201210252357 A CN201210252357 A CN 201210252357A CN 102796053 A CN102796053 A CN 102796053A
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Abstract
The invention relates to a preparation method of a photostabilizer, particularly a preparation method of a benzotriazole photostabilizer. The invention mainly solves the following technical problems in the prior art: in the benzotriazole photostabilizer preparation process, explosions may occur, the production cost is high, toxic gas can generate to pollute the environment, the existing preparation method is not suitable for industrialized production, and the like. The method comprises the following steps: reducing an azobenzene compound with glucose to obtain an intermediate benzotriazole oxynitride, and reducing with aluminum powder to obtain the benzotriazole photostabilizer.
Description
Technical field
The present invention relates to a kind of preparation method of photostabilizer, especially relate to a kind of preparation method of benzotriazole light stabilizer.
Background technology
The compound method of existing benzotriazole light stabilizer mainly is to be raw material from azobenzene compound, carries out cyclisation according to different reducing process.Its existing method of reducing has: hydrazine hydrate reduction method, zinc powder reduction method, sulfide reduction method etc.
For the reductive agent single stage method makes benzotriazole light stabilizer, the patent of report has US4001266, DE2454889, Fr2292708 etc. with the Hydrazine Hydrate 80.The used solvent of this method is a diethylene glycol diethyl ether, and it costs an arm and a leg.And the temperature of reaction is at least 100 ℃, and the side reaction of azo bond fracture takes place easily, forms a large amount of amine sub products.In addition,, need to prolong the reaction times, in the still-process of reacting by heating thing,, have the danger of blasting because ether solvent has the characteristic of easy generation poly oxide in order to distill out the water in the reagent.
A kind of method is Hydrazine Hydrate 80-zinc powder method; Be to be that raw material is reductive agent with the Hydrazine Hydrate 80 with the azobenzene compound; Azobenzene compound is reduced to midbody benzotriazole oxynitride, uses zinc powder midbody benzotriazole oxynitride to be reduced to benzotriazole light stabilizer then as reductive agent.The patent of report has JP53063379.This method need be handled reacting a large amount of Zinc compounds in back owing to used excessive zinc powder and liquid caustic soda, and the excessive basic metal that neutralize make the waste treatment cost increase, and this process steps is loaded down with trivial details, and reaction time is long, contaminate environment.Patent CN 1455773A adopts zinc powder and sulfuric acid, under acidic conditions, reduces, though reduced the consumption of zinc powder, reaction conditions is too violent, and the zinc powder cost is higher.
Another kind method is Hydrazine Hydrate 80-vat powder method; This method is to be that raw material is reductive agent with the Hydrazine Hydrate 80 with the azobenzene compound; Azobenzene compound is reduced to midbody benzotriazole oxynitride, uses vat powder midbody benzotriazole oxynitride to be reduced to benzotriazole light stabilizer then as reductive agent.The patent of report has CN101029032A.This method uses cheap alcoholic solvent to replace ether solvent, preparation cost is reduced, but with hydrochloric acid neutralization reaction liquid the time, excessive vat powder may produce deleterious hydrogen sulfide in reaction process, and contaminate environment is inappropriate for industrialized production.
Summary of the invention
The present invention provides a kind of preparation method of benzotriazole light stabilizer; It mainly is to solve to have the danger of blasting when existing in prior technology prepares benzotriazole light stabilizer; Production cost is higher; And may produce toxic gas, contaminate environment is inappropriate for the technical problem of industrialized production etc.
Above-mentioned technical problem of the present invention mainly is able to solve through following technical proposals:
The preparation method of a kind of benzotriazole light stabilizer of the present invention is characterized in that described method comprises:
A. be raw material with the azobenzene compound shown in the molecule formula I, in the admixture solvent of methyl alcohol or ethanol and alkali, the mol ratio of raw material and alkali is 1: (2-5) with material dissolution; Raw material and methyl alcohol or alcoholic acid mol ratio are 1: (3-5), in mixed solution, add the glucose of 0.5-1.0 mole then by every mole of material, be heated to backflow; Back flow reaction fully after, the solution colour flavescence uses hydrochloric acid neutralization reaction liquid to be 5-7 to pH; Generate deposition; Through filtering, to wash, drying obtains the midbody benzotriazole oxynitride of molecule formula II;
B. the midbody with the molecule formula II is dissolved in the admixture solvent of toluene or YLENE or benzene and alkali; Midbody and alkali mol ratio are 1: (2-5), midbody and toluene or the mol ratio of YLENE or benzene be 1: (3-8), the heating back adds the aluminium powder of little amount of catalyst and 1.2-1.5 mole in mixed solution by every mole of material; When being stirred well to solution and becoming yellow-green colour; Solution is removed by filter insolubles earlier, and the mass concentration of moisturizing to alkali lye is below 10% again, cooled and filtered; Washing, dry that molecular formula is the benzotriazole light stabilizer of (III);
Wherein molecular formula I, II, III are respectively:
（Ⅱ）
Benzotriazole light stabilizer is a kind of good high molecular synthetic material auxiliary agent, have oil resistant, anti-variable color, low volatilization, with characteristics such as the polymer phase dissolubility is good, can prevent effectively that high molecular synthetic material from wearing out, and prolongs its work-ing life under uviolizing.Benzotriazole light stabilizer is widely used in the organic polymers such as plastics, viton, synthon, dyestuff, coating and pigment; Also can make an addition in the makeup; Prevent of the radiation of sunshine middle-ultraviolet lamp to human body skin; The protection HUMAN HEALTH has very high social value and economic worth.Catalyzer is commercially available product commonly used, and consumption also is general conventional amount used.
The present invention uses cheap alcohols and benzene kind solvent, and the recovery is high, and preparation cost is low.Use aluminium powder to be reductive agent, it is few to have a consumption, and preparation cost is cheap, and reaction conditions is gentle, and side reaction is few, and the characteristics that product purity is high are preparing methods of a kind of environmental protection.
As preferably, described R is-H ,-Cl or-Br.
As preferably, described R1 is-H, C1-C12 alkyl, (C1-C8 alkyl) phenyl.
As preferably, described R2 is-H, C1-C12 alkyl, (C1-C8 alkyl) phenyl ,-CnH2n-COOCH3, wherein n is 0,1,2,3,4.
As preferably, described alkali is sodium hydroxide solution, and its concentration is 10-30%.
As preferably, the temperature of back flow reaction is 60-70 ℃ among the described step a, and the reaction times is 2-3 hour.
As preferably, the concentration of hydrochloric acid is 30% among the described step a.
As preferably, described step b adds catalyzer and aluminium powder in admixture solvent temperature of reaction is 60-70 ℃, and the reaction times is 2-3 hour.
As preferably, described step b the mass concentration of moisturizing to alkali lye be below 10% after, be cooled to 10 ℃ of filtrations.
Therefore, the present invention uses cheap alcohols and benzene kind solvent, and the recovery is high, uses aluminium powder to be reductive agent, and it is few to have a consumption, and preparation cost is cheap, the reaction conditions gentleness, and side reaction is few, and the characteristics that product purity is high are preparing methods of a kind of environmental protection.
Embodiment
Through embodiment, do further bright specifically below to technical scheme of the present invention.
Embodiment 1: the preparation method of a kind of benzotriazole light stabilizer of this example the steps include:
A. with the homemade 2-nitro of 27.2g-2 ˊ-hydroxyl-5 ˊ-methyl-benzene (94.5%); 10g sodium hydroxide and 120ml water join in the 500ml there-necked flask, add 14g glucose then, and control reaction temperature is at 60-70 ℃; Back flow reaction 2 hours, solution became light yellow after reaction was accomplished.Slowly the hydrochloric acid neutralization reaction liquid PH of dropping 30% is 6, produces a large amount of yellow mercury oxides, filters, and with 100ml washing 2 times, drying obtains midbody 2-(2 ˊ-hydroxyl-5 ˊ-aminomethyl phenyl) benzotriazole oxynitride 23.6g respectively, and yield is 97.9%;
B. get the above-mentioned 2-that makes (2 ˊ-hydroxyl-5 ˊ-aminomethyl phenyl) benzotriazole oxynitride 23.6g; 12g sodium hydroxide, the 0.5g catalyzer, 80ml toluene and 60ml water join in the 500ml there-necked flask; Control reaction temperature is at 60-70 ℃; Slowly add the 4g aluminium powder, back flow reaction 2-3 hour, solution became oyster after reaction was accomplished.Solution is removed by filter insolubles earlier, pour the water of 100ml in the filtrating into, be cooled to 10 ℃ of filtrations, respectively with 100ml washing 2 times, dry product 2-(2 ˊ-hydroxyl-5 ˊ-aminomethyl phenyl) the benzotriazole 21.6g that gets, overall yield is 96%.
Embodiment 2: the preparation method of a kind of benzotriazole light stabilizer of this example the steps include:
A. with the homemade 2-nitro of 27.2g-2 ˊ-hydroxyl-5 ˊ-methyl-benzene (94.5%); 8g sodium hydroxide and 120ml water join in the 500ml there-necked flask, add 14g glucose then, and control reaction temperature is at 60-70 ℃; Back flow reaction 2 hours, solution became light yellow after reaction was accomplished.Slowly the hydrochloric acid neutralization reaction liquid PH of dropping 30% is 6, produces a large amount of yellow mercury oxides, filters, and with 100ml washing 2 times, drying obtains midbody 2-(2 ˊ-hydroxyl-5 ˊ-aminomethyl phenyl) benzotriazole oxynitride 23.2g respectively, and yield is 96.3%;
B. get the above-mentioned 2-that makes (2 ˊ-hydroxyl-5 ˊ-aminomethyl phenyl) benzotriazole oxynitride 23.2g; 10g sodium hydroxide, the 0.5g catalyzer, 80ml toluene and 50ml water join in the 500ml there-necked flask; Control reaction temperature is at 60-70 ℃; Slowly add the 3.5g aluminium powder, back flow reaction 2-3 hour, solution became oyster after reaction was accomplished.Solution is removed by filter insolubles earlier, pour the water of 100ml in the filtrating into, be cooled to 10 ℃ of filtrations, respectively with 100ml washing 2 times, dry product 2-(2 ˊ-hydroxyl-5 ˊ-aminomethyl phenyl) the benzotriazole 21.1g that gets, overall yield is 93.8%.
Embodiment 3: the preparation method of a kind of benzotriazole light stabilizer of this example the steps include:
A. with the homemade 2-nitro of 35.4g-4-chloro-2 ˊ-hydroxyl-3 ˊ-tertiary butyl-5 ˊ-methyl-benzene (98.1%); 16g sodium hydroxide; 180ml methyl alcohol and 50ml water join in the 500ml there-necked flask, add 12g glucose then, and control reaction temperature is at 60-70 ℃; Back flow reaction 2 hours, solution became light yellow after reaction was accomplished.Slowly the hydrochloric acid neutralization reaction liquid PH of dropping 30% is 6; Produce a large amount of yellow mercury oxides, filter, respectively with 100ml washing 2 times; Drying obtain midbody 2-(2 '-hydroxyl-3 '-tertiary butyl-5 '-aminomethyl phenyl)-5-chlorobenzotriazole oxynitride 31.8g, yield is 95.9%;
B. get the above-mentioned 2-that makes (2 '-hydroxyl-3 '-tertiary butyl-5 '-aminomethyl phenyl)-5-chlorobenzotriazole oxynitride 31.8g; 20g sodium hydroxide, the 0.5g catalyzer, 50ml toluene and 100ml water join in the 500ml there-necked flask; Control reaction temperature is at 60-70 ℃; Slowly add the 4g aluminium powder, back flow reaction 2-3 hour, solution became oyster after reaction was accomplished.Solution is removed by filter insolubles earlier, pours the water of 100ml in the filtrating into,, be cooled to 10 ℃ of filtrations, respectively with 100ml washing 2 times, dry product 2-(2 '-hydroxyl-3 '-tertiary butyl-5 '-aminomethyl phenyl)-5-chlorobenzotriazole 29.5g, overall yield is 93.5%.
Embodiment 4: the preparation method of a kind of benzotriazole light stabilizer of this example the steps include:
A. with the homemade 2-nitro of 39.3g-4-chloro-2 ˊ-hydroxyl-3 ˊ; 5 ˊ-di-t-butyl nitrogen benzide (99.1%), 16g sodium hydroxide, 160ml methyl alcohol and 50ml water join in the 60ml there-necked flask; Add 14g glucose then; Control reaction temperature is at 60-70 ℃, back flow reaction 2 hours, and solution became light yellow after reaction was accomplished.Slowly the hydrochloric acid neutralization reaction liquid PH of dropping 30% is 6, produces a large amount of yellow mercury oxides, filters; Respectively with 100ml washing 2 times; Drying obtains midbody 2-(2 ˊ-hydroxyl-3 ˊ, 5 ˊ-di-tert-butyl-phenyl)-5-chlorobenzotriazole oxynitride 36.4g, and yield is 97.5%;
B. get the above-mentioned 2-that makes (2 ˊ-hydroxyl-3 ˊ, 5 ˊ-di-tert-butyl-phenyl)-5-chlorobenzotriazole oxynitride 36.4g, 18g sodium hydroxide; 0.5g catalyzer; 50ml toluene and 100ml water join in the 500ml there-necked flask, and control reaction temperature slowly adds the 3.3g aluminium powder at 60-70 ℃; Back flow reaction 2-3 hour, solution became oyster after reaction was accomplished.Solution is removed by filter insolubles earlier, pour the water of 100ml in the filtrating into, be cooled to 10 ℃ of filtrations, respectively with 100ml washing 2 times, dry product 2-(2 ˊ-hydroxyl-3 ˊ, 5 ˊ-the di-tert-butyl-phenyl)-5-chlorobenzotriazole 34g that gets, overall yield is 95.1%.
Embodiment 5: the preparation method of a kind of benzotriazole light stabilizer of this example the steps include:
A. with the homemade 2-nitro of 38.9g-2 ˊ-hydroxyl-3 ˊ; 5 ˊ-two tert-pentyl nitrogen benzide (98.4%), 10g sodium hydroxide, 120ml methyl alcohol and 30ml water join in the 500ml there-necked flask; Add 13g glucose then; Control reaction temperature is at 60-70 ℃, back flow reaction 2 hours, and solution became light yellow after reaction was accomplished.Slowly the hydrochloric acid neutralization reaction liquid PH of dropping 30% is 6, produces a large amount of yellow mercury oxides, filters, and with 100ml washing 2 times, drying obtains midbody 2-(2 ˊ-hydroxyl-3 ˊ, 5 ˊ-di-tert-pentyl-phenyl) benzotriazole oxynitride 34.9g respectively, and yield is 95.1%;
B. get the above-mentioned 2-that makes (2 ˊ-hydroxyl-3 ˊ, 5 ˊ-di-tert-pentyl-phenyl) benzotriazole oxynitride 34.9g, 16g sodium hydroxide; 0.5g catalyzer; 60ml toluene and 80ml water join in the 500ml there-necked flask, and control reaction temperature slowly adds the 3.2g aluminium powder at 60-70 ℃; Back flow reaction 2-3 hour, solution became oyster after reaction was accomplished.Solution is removed by filter insolubles earlier, pour the water of 100ml in the filtrating into, be cooled to 10 ℃ of filtrations, respectively with 100ml washing 2 times, dry product 2-(2 ˊ-hydroxyl-3 ˊ, 5 ˊ-di-tert-pentyl-phenyl) the benzotriazole 31.5g that gets, overall yield is 89.7%.
Embodiment 6: the preparation method of a kind of benzotriazole light stabilizer of this example the steps include:
A. with the homemade 2-nitro of 36.4g-2 ˊ-hydroxyl-5 ˊ-uncle's octyl group nitrogen benzide (97.6%); 18g sodium hydroxide; 180ml methyl alcohol and 50ml water join in the 500ml there-necked flask, add 16g glucose then, and control reaction temperature is at 60-70 ℃; Back flow reaction 2 hours, solution became light yellow after reaction was accomplished.Slowly the hydrochloric acid neutralization reaction liquid PH of dropping 30% is 6, produces a large amount of yellow mercury oxides, filters, and with 100ml washing 2 times, drying obtains midbody 2-(2 ˊ-hydroxyl-5 ˊ-uncle's octyl phenyl) benzotriazole oxynitride 32.1g respectively, and yield is 94.7%;
B. get the above-mentioned 2-that makes (2 ˊ-hydroxyl-5 ˊ-uncle's octyl phenyl) benzotriazole oxynitride 32.1g; 15g sodium hydroxide, the 0.5g catalyzer, 100ml YLENE and 60ml water join in the 500ml there-necked flask; Control reaction temperature is at 60-70 ℃; Slowly add the 4g aluminium powder, back flow reaction 2-3 hour, solution became oyster after reaction was accomplished.Solution is removed by filter insolubles earlier, pour the water of 100ml in the filtrating into, be cooled to 10 ℃ of filtrations, respectively with 100ml washing 2 times, dry product 2-(2 ˊ-hydroxyl-5 ˊ-uncle's octyl phenyl) the benzotriazole 28.7g that gets, overall yield is 88.9%.
The above is merely specific embodiment of the present invention, but constitutional features of the present invention is not limited thereto, and any those skilled in the art is in the field of the invention, and the variation of being done or modify all is encompassed among the claim of the present invention.
Claims (9)
1. the preparation method of a benzotriazole light stabilizer is characterized in that described method comprises:
A. be raw material with the azobenzene compound shown in the molecule formula I, in the admixture solvent of methyl alcohol or ethanol and alkali, the mol ratio of raw material and alkali is 1: (2-5) with material dissolution; Raw material and methyl alcohol or alcoholic acid mol ratio are 1: (3-5), in mixed solution, add the glucose of 0.5-1.0 mole then by every mole of material, be heated to backflow; Back flow reaction fully after, the solution colour flavescence uses hydrochloric acid neutralization reaction liquid to be 5-7 to pH; Generate deposition; Through filtering, to wash, drying obtains the midbody benzotriazole oxynitride of molecule formula II;
B. the midbody with the molecule formula II is dissolved in the admixture solvent of toluene or YLENE or benzene and alkali; Midbody and alkali mol ratio are 1: (2-5), midbody and toluene or the mol ratio of YLENE or benzene be 1: (3-8), the heating back adds the aluminium powder of little amount of catalyst and 1.2-1.5 mole in mixed solution by every mole of material; When being stirred well to solution and becoming yellow-green colour; Solution is removed by filter insolubles earlier, and the mass concentration of moisturizing to alkali lye is below 10% again, cooled and filtered; Washing, dry that molecular formula is the benzotriazole light stabilizer of (III);
Wherein molecular formula I, II, III are respectively:
（Ⅱ）
2. the preparation method of a kind of benzotriazole light stabilizer according to claim 1, it is characterized in that described R for-H ,-Cl or-Br.
3. the preparation method of a kind of benzotriazole light stabilizer according to claim 1 is characterized in that described R1 is-H, C1-C12 alkyl, (C1-C8 alkyl) phenyl.
4. the preparation method of a kind of benzotriazole light stabilizer according to claim 1, it is characterized in that described R2 for-H, C1-C12 alkyl, (C1-C8 alkyl) phenyl ,-CnH2n-COOCH3, wherein n is 0,1,2,3,4.
5. the preparation method of a kind of benzotriazole light stabilizer according to claim 1 is characterized in that described alkali is sodium hydroxide solution, and its concentration is 10-30%.
6. the preparation method of a kind of benzotriazole light stabilizer according to claim 1, the temperature that it is characterized in that back flow reaction among the described step a is 60-70 ℃, the reaction times is 2-3 hour.
7. the preparation method of a kind of benzotriazole light stabilizer according to claim 1, the concentration that it is characterized in that hydrochloric acid among the described step a is 30%.
8. the preparation method of a kind of benzotriazole light stabilizer according to claim 1 is characterized in that described step b adds catalyzer and aluminium powder in admixture solvent temperature of reaction is 60-70 ℃, and the reaction times is 2-3 hour.
9. the preparation method of a kind of benzotriazole light stabilizer according to claim 1, it is characterized in that described step b the mass concentration of moisturizing to alkali lye be below 10% after, be cooled to 10 ℃ of filtrations.
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Cited By (3)
| Publication number | Priority date | Publication date | Assignee | Title |
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| CN103450105A (en) * | 2013-07-26 | 2013-12-18 | 浙江常山科润化学有限公司 | Preparation method of benzotriazole ultraviolet absorbent |
| CN105884703A (en) * | 2016-05-31 | 2016-08-24 | 启东金美化学有限公司 | Preparation method of ultraviolet light absorber UV-PS |
| CN107955007A (en) * | 2017-11-17 | 2018-04-24 | 南京工业大学连云港工业技术研究院 | The synthetic method of ultraviolet absorber UV-326 |
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| CN102040561A (en) * | 2010-11-30 | 2011-05-04 | 浙江工业大学 | Method for synthesizing benzotriazole ultraviolet absorber |
| CN102285926A (en) * | 2011-06-30 | 2011-12-21 | 浙江工业大学 | Method for synthesizing benzotriazole compounds |
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Cited By (4)
| Publication number | Priority date | Publication date | Assignee | Title |
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| CN103450105A (en) * | 2013-07-26 | 2013-12-18 | 浙江常山科润化学有限公司 | Preparation method of benzotriazole ultraviolet absorbent |
| CN103450105B (en) * | 2013-07-26 | 2015-06-17 | 浙江常山科润化学有限公司 | Preparation method of benzotriazole ultraviolet absorbent |
| CN105884703A (en) * | 2016-05-31 | 2016-08-24 | 启东金美化学有限公司 | Preparation method of ultraviolet light absorber UV-PS |
| CN107955007A (en) * | 2017-11-17 | 2018-04-24 | 南京工业大学连云港工业技术研究院 | The synthetic method of ultraviolet absorber UV-326 |
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Application publication date: 20121128 |