3-Pyridinecarboxaldehyde → 1-cyclopropyl-5-methoxy-2-(pyridin-3-yl)-1H-benzimidazole

Participants

Reaction Steps

To a solution of N1-cyclopropyl-4-methoxy-benzene-1,2-diamine (0.2 g, 0.0011 mol) and pyridine-3-carbaldehyde (0.12 g, 0.0011 mol) in DMF (5 ml) and H2O (2 ml) was added OXONE® monopersulphate (0.81 g, 0.00132 map. Reaction mass was stirred at room temperature for 3 h. The reaction mixture was basified with 10% K2CO3 solution to pH˜8-10 and extracted with EtOAc (3×20 ml). The combined organic layers were washed with brine dried over Na2SO4 and concentrated under vacuum to afford the crude compound which was purified by column chromatography to obtain title compound 1-cyclopropyl-5-methoxy-2-(pyridin-3-yl)-1H-benzimidazole (376). 1H NMR (400 MHz, DMSO-d6), δ: 9.16 (s, 1H), 8.70 (s, 1H), 8.37 (d, J=8.8 Hz, 1H), 7.55 (d, J=8.4 Hz, 2H), 7.23 (s, 1H), 6.96 (d, J=8.8 Hz, 1H), 3.80 (s, 3H), 1.10 (d, J=6.4 Hz, 2H), 0.64 (s, 2H). MS (M+1): 266.1, Purity 98.98%.

Provenance & Evidence