Phosphorus oxychloride → 7-(2-(4-methylpiperazin-1-yl)ethoxy)-N-(1-((5-(trifluoromethyl)pyridin-2-yl)methyl)-1H-indazol-4-yl)imidazo[1,2-a]pyridine-3-carboxamide

Participants

Reaction Conditions

Reaction Steps

To a solution of 7-(2-(4-methylpiperazin-1-yl)ethoxy)imidazo[1,2-a]pyridine-3-carboxylic acid lithium chloride (0.0653 g, 0.188 mmol) in dry DMA (2.0 mL) at 0° C. was added POCl3 (0.0345 mL, 0.376 mmol) and the mixture was stirred at 0° C. for 30 minutes. 1-((5-(Trifluoromethyl)pyridin-2-yl)methyl)-1H-indazol-4-amine (0.055 g, 0.188 mmol) was added as a DMA solution (1.0 mL) and the mixture was gradually warmed to ambient temperature and stirred overnight. The mixture was concentrated under vacuum and 2M LiOH (2.5 mL) was added. The mixture was stirred for 10 minutes. The mixture was diluted with CHCl3 (20 mL) and with saturated aqueous NaHCO3 and the layers were mixed and separated. The aqueous phase was further extracted with CHCl3 and the combined organic layers were washed with brine and dried over Na2SO4, filtered and concentrated. The product was purified by preparative TLC (15% MeOH/CH2C12 adding 1% 7N NH3/MeOH) to provide 7-(2-(4-methylpiperazin-1-yl)ethoxy)-N-(1-((5-(trifluoromethyl)pyridin-2-yl)methyl)-1H-indazol-4-yl)imidazo[1,2-a]pyridine-3-carboxamide as a tan solid (0.028 g). The solid was dissolved in MeOH (2.0 mL) and HCl (1.88 mL, 3.76 mmol, 2.0M in Et2O) was added. The mixture was stirred for 2 hours and then concentrated. The resulting solid was washed with Et2O and finally with hexanes and dried under vacuum to provide the title compound (0.032 g, 24%). MS (ES+APCI) m/z=579 (M+H-3HCl).

Provenance & Evidence