Ammonium Chloride → N-(3-ethyl-1-((6-methylpyridin-2-yl)methyl)-1H-indazol-4-yl)-7-(2-(4-methylpiperazin-1-yl)ethoxy)imidazo[1,2-a]pyridine-3-carboxamide

Participants

Reaction Steps

To a cooled (ice/water bath) solution of 3-ethyl-1-((6-methylpyridin-2-yl)methyl)-1H-indazol-4-amine (0.080 g; 0.30 mmol) in anhydrous THF (2 mL) under nitrogen was added drop wise LHMDS (1.0 M solution in THF; 0.32 mmol). The mixture was stirred with cooling for 10 minutes and then added to a solution of ethyl 7-(2-(4-methylpiperazin-1-yl)ethoxy)imidazo[1,2-a]pyridine-3-carboxylate (Preparation D) in anhydrous THF (2 mL) with ice/water cooling. An excess of saturated aqueous ammonium chloride solution was added to quench the reaction. The mixture was extracted with DCM. The aqueous phase was then rendered basic by the addition of saturated aqueous sodium carbonate solution and extracted multiple times with DCM and EtOAc. The combined organic extracts were dried over sodium sulfate and concentrated under reduced pressure. The residue was purified by preparative thin layer chromatography on silica, eluting with DCM/MeOH/NH4OH (100:8:1). Purification by thin layer chromatography of the isolated material was repeated under the same conditions to provide N-(3-ethyl-1-((6-methylpyridin-2-yl)methyl)-1H-indazol-4-yl)-7-(2-(4-methylpiperazin-1-yl)ethoxy)imidazo[1,2-a]pyridine-3-carboxamide (53 mg). MS (ES+APCI) m/z=553.1 (M+H).

Provenance & Evidence