Benzotriazole CAS 95-14-7
Factory Supply Benzotriazole CAS 95-14-7 with Best Price
- Appearance: White powder
- Assay: 99. 0%min
- Stock: In stock
- Sample: Available
- Zhishang Chemical: Benzotriazole Suppiler&Manufacturer
Benzotriazole: The Complete Guide
Benzotriazole for Sale
Basic Info of Benzotriazole
1H-Benzotriazole; 1,2,3-Benzotriazole; BTA; Benzisotriazoles
Chemical auxiliaries; Intermediates for pharmaceuticals, pesticides and dyestuffs; Pharmaceutical raw materials; Organic raw materials
What is Benzotriazole?
Benzotriazole is also known as 1,2,3-benzotriazole. Aliases: benzotriazepines, indene triazepines.
Appearance is white or yellowish needle-like crystal, which gradually oxidizes and turns red when exposed to air, soluble in alcohol, benzene, toluene and chloroform; slightly soluble in water. Benzotriazoles are a valuable compound. It is widely used in various aspects of chemistry. Such as preservatives, anticoagulants, lubricants, preparation dye intermediates, plant growth regulators, photographic antifogging agents, etc. as synthetic detergents.
Similar to 1,2,3-triazoles, benzotriazoles also have three tautomers, namely two 1H-configurations and one 2H-configuration. Experimental data and quantum chemical results show that the above equilibrium of benzotriazoles in solution and solid state shifts almost completely to the 1H-side, i.e. the 1H-isomer is the more stable isomer. However, the 2H-form of benzotriazole in the photoexcited triplet state is more stable.
The preparation method of benzotriazole, usually prepares o-aminobenzene diazonium salt with o-phenylenediamine diazotization, and then immediately cyclizes one-step synthesis to obtain benzotriazole crude product, then recrystallizes and filtrates, and dry to obtain benzene And pure triazole.
- Benzotriazole, 5-chlorobenzotriazole and 6-nitrobenzotriazole are all effective antifogging agents and stabilizers in photosensitive materials, and are widely used in photographic paper emulsions and developing solutions.
- Benzotriazole is a useful anti-corrosion agent, especially for copper, which can form a layer of insoluble copper benzotriazole (I) with copper. It also has the same anti-corrosion effect on metal materials such as aluminum, cast iron, steel, nickel, and zinc. It can be added to antifreeze for automobile engines, lubricating oil for grinding and cutting, and cleaning fluid for copper and copper alloys to prevent corrosion and improve. The purpose of the corrosion inhibition effect.
- Benzotriazoles belong to ultraviolet absorbers and are the most important class of light stabilizers. The common ones are 2-(2′-hydroxy-5′-methylphenyl)benzotriazole (UV-P), 2-(2′-Hydroxy-3′-tert-butyl-5′-methylphenyl)-5-chlorobenzotriazole (UV-326), 2-(2′-hydroxy-3′,5′ -Di-tert-butylphenyl)-5-chlorobenzotriazole (UV-327), etc., currently used in polyolefin, polyvinyl chloride, polystyrene, acrylic resin, polyester, polyamide, cellulose ester, etc. It is used as an anti-aging agent in plastics and also as a sunscreen.
- Benzotriazole is used in extreme pressure industrial gear oil, hyperbolic gear oil, anti-wear hydraulic oil, oil film bearing oil, lubricating grease and other lubricating greases, and can be used as anti-rust and gas phase corrosion inhibitor.
- Benzotriazoles and their derivatives can also be used in organic synthesis. 1-Hydroxybenzotriazole is a carboxyl activating reagent in peptide synthesis and is used as an auxiliary reagent in DCC synthesis of peptides. 1-Chlorobenzotriazole can be used as a chlorinating reagent, which transfers a Cl+ to a substrate, and as an oxidant, oxidizing primary and secondary alcohols to aldehydes and ketones.
The Manager has Something to Say
This is William, CEO of Zhishang Chemical Co., Ltd.
Welcome to visit our factory . As the top chemical manufacturer, we have been striving for product quality, innovation , R&D, and customer service for the past 7 years. In the next 10 years or even longer, we are committed to becoming the most reliable chemical supplier in the world , creating a well-known international brand trusted by customers, with the spirit of “one meter wide, ten thousand meters deep”, we continue to focus on product research and development, continue to focus on customer service, continue to improve the supply chain service system, to create a professional chemical supply service team, to achieve win-win long-term cooperation. Please feel free to contact us if you have any questions.
- Email: email@example.com
- Phone: +86 176 5311 3209
- WhatsApp: +86 176 5311 3209
- WeChat: Zhishang17653113209
- Skype: +86 176 5311 3209
If you want to buy benzotriazole, pls contact us to get a free quote.
Application of Benzotriazole
Benzotriazole is an important fine chemical product. It has a wide range of uses, mainly used as a corrosion inhibitor for copper and copper alloys, a metal rust inhibitor, a photographic antifogging agent and an intermediate in organic synthesis. It is also widely used in paint additives, preservatives for synthetic detergents, anticoagulants, lubricant additives, synthetic dye intermediates, polymer material stabilizers, plant growth regulators, anti-discoloration agents, gas phase corrosion inhibitors and ultraviolet light absorption. agent.
The use of benzotriazole in combination with a variety of corrosion inhibitors can improve the corrosion inhibition effect. It can also be used in conjunction with a variety of scale inhibitors, bactericidal and algicides. It can produce better corrosion inhibition effect for closed circulating cooling water systems. Adding benzotriazole to antifreeze and coatings for automobiles can play the role of protective materials. In the machining process, adding benzotriazole to the cutting oil can keep the processed copper from discoloring.
Preparation of Benzotriazole
Many researchers at home and abroad have done a lot of research work on the synthesis of benzotriazoles. So far, the reported synthetic routes include o-phenylenediamine method, benzimidazolone method, o-nitrophenylhydrazine method, o-nitrochlorobenzene method, and the preparation of benzotriazepine from sodium benzotriazole azole method.
The o-Phenylenediamine method is the most classic method for synthesizing benzotriazole, which includes the normal-pressure synthesis method of o-phenylenediamine and the improved high-pressure method of o-phenylenediamine.
o-Phenylenediamine normal pressure method: first dissolve o-phenylenediamine in acetic acid aqueous solution, and configure about 40% sodium nitrite aqueous solution; the two solutions are pre-cooled to 1-5 °C, mixed and reacted, and kept at In the ice bath, rapidly heat up to 80°C to close the ring to generate benzotriazole, cool and filter, wash with water to obtain the crude product; be distilled at an absolute pressure of 2000Pa, collect the fraction at 201～204°C, obtain the product with benzene crystallization, and collect the product. The rate is 70% to 80%. At present, most domestic manufacturers use this method. However, this method has the disadvantages of high toxicity of o-phenylenediamine, consumption of a large amount of acetic acid, difficulty in product purification, low yield and harsh reaction conditions. From the 1970s to the 1970s, many improvements were made to the above process, which improved the product yield.
Later, Joseph of the United States switched to the method of dropping an aqueous solution of sodium nitrite, and the initial reaction temperature was increased to 55-60 °C. The reaction mixture was extracted with mixed amyl alcohol, distilled under a pressure of 266.6Pa, and the fractions at 157-170 °C were collected. Cooling, filtering and drying can obtain nearly colorless benzotriazole, and the yield can reach 96%. This method is easy to control the temperature and eliminates the ice bath that is not conducive to industrial production. The mixture after the reaction is extracted with hexanol, and the extraction process is carried out. Add polyethylene glycol 200 to the liquid, first recover hexanol by vacuum distillation, and then azeotropically steam out the polyethylene glycol solution of benzotriazole under the pressure of 266.6Pa. This improvement not only makes benzotriazole The yield increased to 95.1%, and the risk of decomposition and explosion of benzotriazole in vacuum distillation was reduced. The former West German Rochat used potassium nitrite instead of sodium nitrite, and in the presence of xylene and acetic acid, the reaction temperature was 20 ~ 50 ℃, the yield can reach 97%.
- o-Phenylenediamine high-pressure method: The o-phenylenediamine high-pressure method was invented by John in the United States. The molar ratio of o-phenylenediamine to sodium nitrite is 1:1 to 1.05, the reaction temperature is 200 to 300°C, and the pressure It is 4.8×106～6.9×106Pa. After the reaction is completed, the pH value is adjusted to 6 with acid. Since no acid is involved in the diazotization ring-closure reaction, the chance of generating dark-colored tars by diazotization coupling is reduced, thereby improving the product. At the same time, the purification of the product becomes easy. For example, o-phenylenediamine is reacted with 37% aqueous sodium nitrite solution at a temperature of 260 ° C and a pressure of 3.0 × 106 to 3.3 × 106 Pa. After 3 hours of reaction Cooling, the pH value is adjusted from 11.7 to 6 with concentrated sulfuric acid to obtain benzotriazole with a purity of 100% and a yield of 96.9%. This process does not require acetic acid, with few side reactions, little pollution, high yield and reaction time Short, continuous production. Chinese researchers have successfully synthesized benzotriazole by one-step pressurization. Sodium benzotriazole is synthesized from o-phenylenediamine and sodium nitrite in one step by pressurization, and then acidified and crystallized to obtain the product. The cost of this method is reduced by 50% to 70%, and two domestic blanks are filled.