反应详情

温度

70 °C

To a mixture of 5-chloro-3-nitro-4-(4-(pyridin-4-ylmethyl)piperazin-1-yl)pyridin-2-amine (0.031 g, 0.09 mmol), and ethanol (3.0 ml) was added 4-methoxybenzaldehyde (0.020 g, 0.14 mmol) with the aid of ethanol (1 ml) followed by a freshly prepared aqueous solution of Na2S2O4 (1M; 0.36 ml, 0.36 mmol). The reaction mixture was heated at 70° C. for 5 h, then allowed to cool to room temperature and the solvents were removed in vacuo. The residue was triturated with water, and the precipitate was collected by filtration, washed with water, ethanol, and diethyl ether. This material was further purified on a 10 g isolute silica column using a gradient of methanol (0 to 5%) in ethyl acetate/dichloromethane (v/v; 1:1) as eluant. The title compound was obtained as a pale yellow solid (0.007 g, 18%); 1H-NMR (500 MHz, DMSO-d6) 2.61 (br s, 4H, piperazine N(CH2)2), 3.71 (br s, 4H, piperazine N(CH2)2), 3.61 (s, 2H, NCH2), 3.83 (s, 3H, OMe), 7.09 (d, J=8.85 Hz, 2H) and 8.12 (d, J=8.80 Hz, 2H) (3,5-C6H4OMe and 2,6-C6H4—OMe), 7.40 (d, J=5.86 Hz, 2H), and 8.54 (d, J=4.48 Hz, 2H) (pyrid-4-yl protons), 8.08 (s, 1H, imidazo[4,5-b]pyridine 5-H), 13.37 (s, 1H, imidazo[4,5-b]pyridine N—H);

1. temperatureto cool to room temperature
2. customthe solvents were removed in vacuo
3. customThe residue was triturated with water
4. filtrationthe precipitate was collected by filtration
5. washwashed with water, ethanol, and diethyl ether
6. customThis material was further purified on a 10 g isolute silica column