Aluminum chloride-catalyzed C-alkylation of pyrrole and indole with chalcone and bis-chalcone derivatives

摘要

The AlCl3-catalyzed alkylation of pyrrole (2) with chalcone (1a-i) at a ratio of 8:1 in the presence of 10mol% AlCl3 gave the solely 2-alkyl pyrroles (3a-i) at room temperature for 12 in good yields. The same reaction was performed with pyrrole (2) and chalcone at a ratio of 1:3 in CH3CN at rt for 3h to achieve 2,5-dialkyl pyrroles (4a-f). In addition, the reaction of the pyrrole (2) and indole (7) on 1,4-phenylene bis-chalcones (5a-g) at the ratio of 8:1 at rt for 24h gave the double-addition products 6a-g and 8a-g in good yields, respectively. The structure of the products was confirmed by H-1 and C-13 NMR spectroscopy and elemental analysis.