Hydrochloric Acid → 1-[4-(7-Phenyl-imidazo[1,2-b]pyridazin-6-yl)-phenyl]-cyclobutylamine

Participants

Reaction Steps

105 mg (0.24 mmol) {1-[4-(7-Phenyl-imidazo[1,2-b]pyridazin-6-yl)-phenyl]-cyclobutyl}-carbamic acid tert.-butyl ester, (intermediate example Int-2-0, slightly contaminated), were stirred with 2.3 mL 4M hydrogen chloride in dioxane for 10 days at room temperature. After evaporation of the solvent the residue was brought to pH 9 with saturated aqueous sodium bicarbonate solution. The mixture was stirred for four hours. The precipitate was sucked off and washed with water. The solid substance was dissolved in dichloromethane and purified by chromatography on silicagel (eluents: dichloromethane/methanol) resulting in 49.6 mg of the desired compound which was however yet contaminated. Due to these impurities the compound was again purified by HPLC yielding 21.1 mg (23.7%) of the title compound.

Provenance & Evidence