Microwave-Assisted Synthesis of N-2-Benzyl-3-(4-ethoxycarbonylphenyl)indazole Derivatives

- The microwave-assisted synthesis for promoting N-2 substituted indazoles as the major products were successfully developed by treating 3-(4-ethoxycarbonylphenyl)indazoles with various substituted benzyl chloride (benzyl, o-chlorobenzyl, m-chlorobenzyl, and p-chlorobenzyl chloride) in the presence of two equivalents of triethylamine. The result was better than two trandional methods including the directly substitution with benzyl chloride and Mitsunobu reaction with benzyl alcohol.