1,4-Dioxane → 2-Bromo-1-(6-(2-(4-fluorophenyl)-2-methylpropylamino)pyridazin-3-yl)ethanone

Participants

Reaction Conditions

Reaction Steps

6-chloro-N-(2-(4-fluorophenyl)-2-methylpropyl)pyridazin-3-amine (300 mg, 1.1 mmol, 1.0 equiv) and dioxane (5 mL) were added to a microwave vial and sonication was applied until the mixture was homogeneous. Tributyl(1-ethoxyvinyl)stannane (475 μL, 1.4 mmol, 1.3 equiv) and trans-dichlorobis(triphenylphosphine)palladium (30 mg, 0.04 mmol, 0.03 equiv) were then added, and the reaction was heated in a microwave reactor at 150° C. for 20 min. The reaction was concentrated, dissolved in EtOAc (25 mL), and mixed with 2.0 M potassium fluoride (5 mL). The mixture was filtered through celite, and then washed with water, dried over Na2SO4, filtered, and concentrated. The crude solid was redissolved in 50% THF/water (4 mL), followed by the addition of NBS (300 mg, 1.7 mmol, 1.5 equiv). The reaction mixture was stirred for 1 h and then diluted with brine (20 mL) and ethyl acetate (20 mL). After transferring to a separatory funnel and shaking, the organic layer was separated from the aqueous layer. The organic layer was then dried over Na2SO4, filtered, and concentrated to give a brown oil that was purified by silica gel chromatography (0-100% EtOAC/hexanes) to afford 270 mg of 2-bromo-1-(6-(2-(4-fluorophenyl)-2-methylpropylamino)pyridazin-3-yl)ethanone as an orange oil.

Provenance & Evidence