2,2'-thiene-2,5-diylbis(1,3-benzoxazole)
Fluorescent brightener 185
CAS: 2866-43-5;12224-41-8
Molecular Formula: C18H10N2O2S
2,2'-thiene-2,5-diylbis(1,3-benzoxazole) - Names and Identifiers
| Name | Fluorescent brightener 185 |
| Synonyms | Ebf FBA185 Optical Brightener EBF Fluorescent brightener EBF fluorescent brightener 185 Fluorescent Brightening Ebf Optical Brightening Agent EBF C.I. Fluorescent Brightener 172 2,5-di(benzoxazol-2-yl)thiophene 2.5-bis-(benzoxazol-2-)thiophene 2,5-Bis(2-benzoxazolyl)thiophene 2,2'-thiophene-2,5-diylbis(benzoxazole) 2,2'-(2,5-thiophenediyl)bis-benzoxazole 2,2'-thiene-2,5-diylbis(1,3-benzoxazole) Benzoxazole, 2,2-(2,5-thiophenediyl)bis- |
| CAS | 2866-43-5 12224-41-8 |
| EINECS | 220-685-1 |
| InChI | InChI=1/C18H10N2O2S/c1-3-7-13-11(5-1)19-17(21-13)15-9-10-16(23-15)18-20-12-6-2-4-8-14(12)22-18/h1-10H |
2,2'-thiene-2,5-diylbis(1,3-benzoxazole) - Physico-chemical Properties
| Molecular Formula | C18H10N2O2S |
| Molar Mass | 318.35 |
| Density | 1.385 |
| Melting Point | 216-220°C |
| Boling Point | 466.4±30.0 °C(Predicted) |
| Flash Point | 235.9°C |
| Water Solubility | 9.551ug/L(25 ºC) |
| Vapor Presure | 1.98E-08mmHg at 25°C |
| Appearance | Bright yellow crystal powder |
| pKa | 1.27±0.10(Predicted) |
| Storage Condition | Room Temprature |
| Refractive Index | 1.6000 (estimate) |
| Physical and Chemical Properties | This product is light yellow crystalline powder, bright blue fluorescence. The melting point was 218-219 °c. Miscible with water in any proportion. Resistant to hard water, acid and alkali. After using it, the fabric is resistant to light, chlorine bleaching and washing. |
| Use | Mainly used for commercial whitening agent EB, can also be used for all kinds of polyolefin plastics, BS engineering plastics, organic glass and other whitening |
2,2'-thiene-2,5-diylbis(1,3-benzoxazole) - Risk and Safety
| Toxicity | LD50 oral in rat: > 30gm/kg |
2,2'-thiene-2,5-diylbis(1,3-benzoxazole) - Reference
| Reference Show more | 1. He Zhi Hua, Zuojun Feng, Xiong Ma Jian, Zhu Bijun. Determination of fluorescent whitening agents in pharmaceutical composite membranes by high performance liquid chromatography [J]. Journal of Pharmaceutical Analysis, 2020,40(09):1645-1652. |
2,2'-thiene-2,5-diylbis(1,3-benzoxazole) - safety
Open Data Verified Data
This product can be managed according to general industrial chemicals. When using it, gloves and protective glasses should be worn to avoid direct contact with the skin and eyes. If it gets on the skin, rinse with water and soap. Place in a cool and dry warehouse to prevent exposure to sunlight and rain.
Last Update：2023-10-20 08:59:47
2,2'-thiene-2,5-diylbis(1,3-benzoxazole) - Preparation method
Open Data Verified Data
1. Synthesis of 2-Chloromethylbenzoxazole (Feed as Mass Fraction)
Add 54.5 parts of o-aminophenol and 220 parts of chlorobenzene into a reactor, stir to form a suspension, and add 0.6 parts of catalyst pyridine. Under nitrogen protection and stirring, add 20.0 parts of 2-chloroacetyl chloride dropwise. After the dropwise addition, heat it to 80 ℃. Gradually heat it to 100 ℃ during the reaction, keep it warm for 2 hours, and add 3 parts of o-toluene sulfonic acid. Under continued nitrogen protection, stir and reflux for 5 hours. Steam out chlorobenzene to obtain a brown oily substance called 2-chloromethylbenzoxazole.
2. Synthesis of bis (benzoxazol-2-methyl) sulfide
Put 63 portions of sodium sulfide into a reaction kettle, add 3 times the amount of water, and stir to dissolve. Subsequently, 0.8 parts of benzyl n-tributyl ammonium bromide were added. Cool to 10 ℃. The one generated in the previous step α- Chloromethylbenzoxazole was added to dichloromethane to form a solution. Add this solution dropwise to the sodium sulfide solution, react for 3 hours, let it stand, discard the water layer, wash the organic layer with water to neutral, mix dry sodium sulfate with the washed organic matter, dehydrate, and then filter out sodium sulfate. The filtrate is vacuum evaporated into dichloromethane. Cool and crystallize, then recrystallize with methanol. Obtain pure bis (benzoxazol-2-methyl) sulfide.
3. Generation of whitening agent EBP
First, prepare a sodium methoxide solution using metallic sodium and anhydrous methanol. Cool the solution to 0 ℃, add glyoxal, and stir for 4 hours to gradually generate crystalline precipitates. 2,5-Dibenzoxazolylthiophene is neutralized with dilute acid, filtered, and the filter cake is washed to neutral with water, and then vacuum dried to obtain the crude whitening agent EBF. Then recrystallize in chlorobenzene to obtain a high-quality product.
Last Update：2024-01-02 23:10:35
2,2'-thiene-2,5-diylbis(1,3-benzoxazole) - Reference Information
| EPA chemical information | Information provided by: ofmpub.epa.gov (external link) |
| use | this product is used as whitening treatment agent for vinegar fiber, nylon, polyester, polypropylene fiber, chlorine fiber and blended fiber. It is mainly used for commercial whitening agent EB, and can also be used for whitening and brightening of various polyolefin plastics, BS engineering plastics, plexiglass, etc. |
| production method | synthesis of 2-chloromethylbenzo [soxazole] (the feed is mass fraction) 54.5 parts of o-aminophenol and 220 parts of chlorobenzene are put into a reaction kettle, stirred to form a suspension, and 0.6 parts of catalyst pyridine are added. Under nitrogen protection and stirring, 20.0 parts of 2-chloroacetyl chloride are added dropwise, heated to 80 ℃ after dropwise addition, gradually heated to 100 ℃ in the reaction, kept warm for 2 h, 3 parts of o-toluenesulfonic acid are added, stirred and refluxed for 5 h under the condition of continuous nitrogen filling protection. Chlorobenzene is steamed out to obtain brown oil, namely 2-chloromethylbenzo [soxazole]. Synthesis of bis (benzo [oxazole] -2-methyl) sulfide 63 parts of sodium sulfide are put into the reaction kettle, 3 times the water is added, and the solution is stirred. Then add 0.8 parts of benzyl n-tributylammonium bromide. Cold to 10 ℃. Add the α-chloromethyl benzo [oral] azole generated in the previous step to dichloromethane and prepare a solution. Then add this solution dropwise to the sodium sulfide solution, react for 3 h, stand still, discard the water layer, wash the organic layer to neutral, stir and mix with dry sodium sulfate and organic matter after washing, dehydrate, and then filter out sodium sulfate. The filtrate evaporates methylene chloride in vacuum. Cooling crystallization, then recrystallization with methanol. The pure product is bis (benzo [oxazole] -2-methyl) sulfide. The formation of the whitening agent EBP is first prepared with sodium metal and anhydrous methanol to prepare sodium methoxide solution, the solution is cooled to 0 ℃, and glyoxal is added to stir for 4 hours to gradually generate crystallization precipitation. That is, 2, 5-dibenzo [oxazole] azolylthiophene, neutralized with dilute acid, filtered, the filter cake washed with water to neutral, and then vacuum dried to obtain crude whitening agent EBF. Then recrystallize in chlorobenzene to obtain fine products. |
Last Update：2024-04-09 19:05:11
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Product Name: Fluorescent brightener 185 Request for quotationCAS: 2866-43-5
Tel: +86-17551318830
Email: r@reformchem.com
Mobile: +86-17551318830
QQ: 3785839865
Product Name: 2,5-Bis(2-benzoxazolyl)thiophene Visit Supplier Webpage Request for quotation
CAS: 2866-43-5
Tel: 18301782025
Email: 3008007409@qq.com
Mobile: 18021002903
QQ: 3008007409
Wechat: 18301782025
CAS: 2866-43-5
Tel: 18301782025
Email: 3008007409@qq.com
Mobile: 18021002903
QQ: 3008007409
Wechat: 18301782025
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