A Simple, Versatile Synthetic Route toN-1-Aryl-, -Heteroaryl-, - Acylmethyl-, -Carboxymethyl-and -Alkyl-benzotriazoles via Regiospecific or Highly Regioselective Substitutions of Benzotriazole

All articles of this category In the absence of any added base in refluxing benzene or toluene, benzotriazole replaces the halogen atom of an α-halogenated ketone or a carboxylic ester to give the corresponding N -1-substituted benzotriazole as the only isomer. 2-Bromopyridine and 1-chloro-2,4-dinitrobenzene reacted similarly with benzotriazole to afford the corresponding N -1-substituted benzotriazole derivatives in quantitative yields. Alkyl halides reacted regioselectively to afford the N -1-alkylbenzotriazoles in ratios of more than 10 to 1 over the N -2 isomers. An α-(benzotriazol-1-yl)carboxylic ester was hydrolyzed into the corresponding carboxylic acid, which upon heating under-went smooth decarboxylation into the corresponding 1-alkylbenzotriazole.