2-Hydroxyisobutyric acid → Pyrrolo[1,2-b]pyridazine-3-carboxamide

Participants

Reaction Steps

To a solution of 6-bromo-4-(((3R,4R)-3-ethylpiperidin-4-yl)amino)pyrrolo[1,2-b]pyridazine-3-carboxamide (275 mg, 0.75 mmol) and 2-hydroxy-2-methylpropanoic acid (156 mg, 1.501 mmol) in dichloromethane (3.8 ml) were added DIEA (1.3 ml, 7.5 mmol) and HATU (571 mg, 1.501 mmol). The reaction was stirred at room temperature for 14 hrs. The product mixture was partitioned between ethyl acetate and water. The ethyl acetate layer was washed with brine, dried over sodium sulfate, filtered, and concentrated under reduced pressure. The crude product was purified via medium pressure chromatography (silica gel column, EtOAc/hexanes eluent, 0-100% gradient elution) to yield 6-bromo-4-((3R,4R)-3-ethyl-1-(2-hydroxy-2-methylpropanoyl)piperidin-4-yl)amino)pyrrolo-[1,2-b]pyridazine-3-carboxamide (240 mg, 0.531 mmol, 70.7% yield) as a white solid. LCMS (Method K) m/z 454.4 ([M+H]+).

Provenance & Evidence