| abstract |
Compounds of formula I or II n nwhere R is an aryl moiety, such as phenyl, naphthyl or biphenylyl, or is phenyl substituted by one or more trifluoromethyl, bromo or cyano, and E 1 and E 2 are independently hydrogen, alkyl, aralkyl and the like are prepared by reaction of a benzotriazole substituted on the 5-position of the benzo ring by a halogen atom with a arylboronic acid or ester in the presence of a transition-metal catalyst, such as palladium (II) diacetate. The benzotriazole compounds of formula I are particularly efficacious as stabilizers for automotive coatings and candle wax. |