- An anti-ultraviolet type single-carbonization two imine compound and its preparation method
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The invention will be benzo triazole structure and connected with the carbodiimide structure, to provide a molecular weight, the lower the melting point of the traditional single-carbodiimide high anti-ultraviolet type single-carbonization two imine compound, to overcome the traditional single-carbodiimide under the high temperature easily from the polyester, polyamino compounds to the disadvantages in the migration, improving the material water-resistant xie kang aging performance. The invention synthetic anti-ultraviolet type single-carbodiimide compound can be used as an anti-hydrolysis stabilizing agent for the polyurethane and polyester elastomer, and in particular can be used for photovoltaic industry, biodegradable material and the like.
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- 2 - PHENYL - 1, 2, 3 - BENZOTRIAZOLES FOR UV RADIATION ABSORBANCE
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The present invention relates to novel benzotriazoles and to novel topical compositions comprising these benzotriazoles. Furthermore, the invention relates to the use of the novel benzotriazoles as photostabilizer and solubiliser for dibenzoylmethane deri
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Page/Page column 49
(2011/08/04)
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- One-pot synthesis of benzotriazoles and benzotriazole 1-oxides by reductive cyclization of o-nitrophenylazo compounds with benzyl alcohol
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Reductive cyclization of 2-[(2-nitrophenyl)azophenols 1 with benzyl alcohol and sodium hydroxide afforded 2-(2H-benzotriazol- 2-yl)phenols 3 and their 1-oxide 2 in good to excellent yields.
- Farkas, Renata,Toerincsi, Mercedes,Kolonits, Pal,Alonso, Oscar Jimenez,Novak, Lajos
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experimental part
p. 2579 - 2588
(2010/04/27)
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- Processes for the preparation of benzotriazole UV absorbers
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Provided is a process for preparing 2H-benzotriazole UV absorbers containing a perfluoroalkyl moiety at the 5-position of the benzo ring, for example a trifluoromethyl group, which involves diazotizing the perfluoroalkyl substituted o-nitroaniline using concentrated sulfuric acid plus sodium nitrite or nitrosylsulfuric acid to form the corresponding monoazobenzene intermediate via the diazonium salt intermediate which is reduced to the corresponding 5-perfluoroalkyl substituted 2H-benzotriazole UV absorber compound by conventional reduction means. Also provided is a novel one-pot, multiphase reaction for the preparation of 2(2-nitrophenylazo) substituted phenols, which are precursors for 2H-benzotriazole UV absorbers.
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- Preparation of Some 2-(2' H-Benzotriazol-2'-yl)phenol Ultraviolet Absorbers: Application of the Transalkylation Reaction
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When 2-(2' H-benzotriazol-2'-yl)phenols containing t-alkyl substituents are warmed in toluene solution with an aluminium chloride/nitromethane catalyst, the t-alkyl groups are transferred to the solvent (toluene).This transalkylation reaction has been used to prepare not readily accessible or previously inaccessible 2-(2' H-benzotriazol-2'-yl)phenols, a class of ultraviolet absorbers widely used in industry.
- Rosevear, Judi,Wilshire, John F.K.
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p. 1163 - 1176
(2007/10/02)
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- Tetrahydrophthalimide methyl-2-phenylbenzatriazoles
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A compound of the formula, wherein R1 is hydrogen or a halogen atom, R2 is STR1 R3 is hydrogen, an alkyl group, a cycloalkyl group or an aralkyl group, and n is an integer of 1 or 2, which is useful as ultraviolet absorber.
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