Organic Reactions in Ionic Liquids: A Simple Highly Regioselective or Regiospecific Substitutions of Benzotriazole

In the absence of any added base in ionic liquids [Bmim][BF 4 ], benzotriazole replaces the halogen atom of an α-halogenated ketone or α-halogenated carboxylic ester to give the corresponding N-1-substituted benzotriazole as the only isomer, and 1-chloro-2,4-dinitrobenzene reacted similarly with benzotriazole to afford the N-1-substituted benzotriazole in a good yield.Alkyl halides reacted regioselectively to afford the N-1-alkylbenzotriazole in ratios of more than 15 to 1 over the N-2-isomer.