Ethanol → 6-Chloro-2-(4-morpholin-4-ylmethyl-phenyl)-7-(4-pyridin-3-ylmethyl-piperazin-1-yl)-3H-imidazo[4,5-b]pyridine

Participants

Reaction Conditions

Reaction Steps

To a mixture of 5-chloro-3-nitro-4-(4-pyridin-3-ylmethyl-piperazin-1-yl)-pyridin-2-ylamine (0.031 g, 0.09 mmol) and EtOH (3.0 ml) was added 4-morpholin-4-ylmethyl-benzaldehyde (0.025 g, 0.12 mmol) followed by a freshly prepared aqueous solution of Na2S2O4 (1M; 0.36 ml, 0.36 mmol). The reaction mixture was stirred at 80° C. for 20 h, then allowed to cool to room temperature and concentrated in vacuo. The resulting residue was absorbed on silica, and the free-running powder was placed on a 10 g isolute silica column. Elution with a gradient of methanol (2 to 13%) in ethyl acetate/dichloromethane (v:v; 4:1) afforded a yellow solid. The title compound was obtained as a pale yellow solid after trituration with diethyl ether (0.014 g, 30%); 1H-NMR (500 MHz, DMSO-d6) 2.38 (br s, 4H) and 3.59 (t, J=4.5 Hz, 4H) (morpholine N(CH2)2 and morpholine O(CH2)2), 2.62 (br s, 4H, piperazine N(CH2)2), 3.53 (s, 2H) and 3.61 (s, 2H) (NCH2-pyridyl and C6H4CH2N), 3.71 (br s, 4H, piperazine N(CH2)2), 7.39 (dd, J=5.30, 8.2 Hz, pyridine 5-H), 7.47 (d, J=8.2 Hz, 2H) and 8.12 (d, J=8.7 Hz, 2H) (3,5-C6H4— and 2,6-C6H4—), 7.78 (d, J=6.9 Hz, 1H, pyridine 4-H), 8.14 (s, 1H, imidazo[4,5-b]pyridine 5-H), 8.50 (dd, J=1.50, 4.6 Hz, 1H, pyridine 6-H), 8.56 (d, J=1.5 Hz, 1H, pyridine 2-H), 13.42 (br s, 1H, imidazo[4,5-b]pyridine N—H);

Provenance & Evidence