反应详情

温度

70 °C

To a mixture of 5-bromo-3-nitro-4-(4-(pyridin-2-ylmethyl)piperazin-1-yl)pyridin-2-amine (0.043 g, 0.11 mmol), ethanol (4 ml), and 4-dimethylaminobenzaldehyde (0.021 g, 0.14 mmol) was added a freshly prepared aqueous solution of Na2S2O4 (1M; 0.44 ml, 0.44 mmol). The reaction mixture was heated at 70° C. for 4 h, then allowed to cool to room temperature and the solvents were removed in vacuo. The residue was absorbed on silica gel and the free running powder was placed on a 10 g isolute silica column which was eluted with 1% to 5% methanol in ethyl acetate. The title compound was obtained as a yellow solid after trituration with diethyl ether (0.006 g, 11%); 1H-NMR (500 MHz, DMSO-d6) 1H-NMR (500 MHz, DMSO-d6) 2.66 (br s, 4H, piperazine N(CH2)2), 3.00 (s, 6H, N(CH3)2), 3.65 (br s, 4H, piperazine N(CH2)2), 3.70 (s, 2H, NCH2), 6.82 (d, J=9.00 Hz, 2H) and 8.01 (d, J=8.76 Hz, 2H) (3,5-C6H4NMe2 and 2,6-C6H4—NMe2), 7.28 (dd, J=4.00, 5.86 Hz, 1H), 7.53 (d, J=9.00 Hz, 1H), 7.80 (td, J=1.70, 9.09 Hz, 1H), and 8.52 (d, J=4.96 Hz, 1H) (pyrid-2-yl protons), 8.14 (s, 1H, imidazo[4,5-b]pyridine 5-H), 13.13 (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 absorbed on silica gel
4. washwas eluted with 1% to 5% methanol in ethyl acetate