Use of a novel reagent has been established for the synthesis of a series of 4,5-diaryl-2H-1,2,3-triazoles (6a-i and 9a-e) from cyanostilbene analogs of benzo[b]thiophene, benzo[b]furan and indole, catalyzed by L-proline via Lewis base-catalyzed one-step [3+2]cycloaddition of azide. This method provides an efficient, simple and environmentally benign procedure that affords good yields and relatively short reaction times.
Keywords: 4,5-Diaryl-2H-1,2,3-triazoles; Heteroaryl cyanostilbenes; L-Proline; Sodium azide; [3+2] Cycloaddition of azide.