2H-Benzotriazol

Nitro-azobenzole werden primar zu den analogen Hydrazobenzolen reduziert. In Ammoniakpuffer-Losung bildet sich an Quecksilber bei —0,5 bis —0,65 V quantitativ das 2-Aryl-2H-benzotriazol-l-oxid. Bei —1,0 bis —1,4 V entsteht ebenfalls quantitativ das... 

Di-ferf-butyl-6-(5-chloro-2H-benzotriazol-2-yl)phenol, UV absorber (23)... 

H-Benzotriazol-2-yl)-4-(l, 1,3,3-tetramethylbutyl)-phenol (29) Cyasorb UV-3638 Cytec Corp. 

Methyl-3,4-dihydro-2tf-pyrido[l,2-a]pyrimidin-2-one is used in fluorescence (chiral) derivatization of carboxylic acids in HPLC with different 2-substituted 2H-benzotriazoles 688 in the presence of 2-bromo-1-ethylpyridinium tetrafluoroborate at room temperature (89MI2, 89MI15). This sensitive method has proved useful for the determination of carboxylic acids (e.g., ibuprofen) in small amounts of biological samples (89MI2). 

Copolymeirization provides an unique approach to the synthesis of polyfunctional stabilizers. E.g. terpolymers of 4-isopropenyl-2,6-di-terr-butylphenol, methyl methacrylate and 2-(2-hydroxy-5-isopropenyl)-2H-benzotriazole or poly[4-(2,2,6,6-tetramethylpiperidyl) methacrylate-co-4-hydroxy-3,5-di-tert-butyl-benzyl methacrylate] (96), having M 5,400, posses properties of AO and LS [108]. 

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