Compounds of formula I or II ##STR1## where R is a heteroaryl moiety, such as 3-pyridyl, or T is a heteroaryl moiety, such as thien-2,5-diyl, and E.sub.1 and E.sub.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 heteroarylboronic 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.