Ethanol → 6-Bromo-2-(4-methoxyphenyl)-7-(4-((1-methyl-1H-imidazol-2-yl)methyl)piperazin-1-yl)-3H-imidazo[4,5-b]pyridine

Participants

Reaction Conditions

Reaction Steps

To a mixture of 5-bromo-4-(4-((1-methyl-1H-imidazol-2-yl)methyl)piperazin-1-yl)-3-nitropyridin-2-amine (0.035 g, 0.088 mmol, 1 eq), EtOH (2 mL) and DMF (0.3 mL), p-anisaldehyde (0.013 g, 0.097 mmol, 1.1 eq) was added followed by a freshly prepared aqueous solution of Na2S2O4 (1M; 0.26 mL, 0.26 mmol). The reaction mixture was heated at 85° C. for 24 h, then allowed to cool to room temperature, and diluted with DCM and a few drops of aqueous NH3 until complete dissolution was observed. This solution was deposited on two preparative silica TLC plates and eluted with DCM/MeOH (v/v; 94:6). The title compound was obtained after trituration with diethyl ether as a dark yellow solid (0.009 g, 21%); 1H-NMR (500 Mz, DMSO-d6): δ 2.55-2.63 (m, 4H, piperazine N(CH2)2), 3.58-3.67 (m, 6H, piperazine N(CH2)2 and NCH2), 3.72 (s, 3H, imidazole Me), 3.84 (s, 3H, OMe), 6.77 (d, 1H, J=1.0 Hz, imidazole 4-H), 7.07-7.13 (m, 3H), 8.13 (d, J=8.5 Hz, 2H), 8.20 (s, 1H, imidazo[4,5-b]pyridine 5-H), 13.34 (br s, 1H, imidazo[4,5-b]pyridine N—H); LC (Method B)-MS (ESI, m/z): Rt=3.33 min—482/484 [(M+H+), Br isotopic pattern, 100%]. ESI-HRMS: Found: 482.1297, calculated for C22H25BrN7O (M+H)+: 482.1304.

Provenance & Evidence