1,4-Dioxane → 2-Bromo-1-(6-chloropyridazin-3-yl)ethanone

Participants

Reaction Conditions

Reaction Steps

To a stirring solution of dioxane (100 mL, degassed) was added 3,6-dichloropyridazine (5.0 g, 34 mmol), Cl2Pd(PPh3)2 (2.4 g, 3.4 mmol), and tributyl(1ethoxyvinyl)tin (18.2 g, 50 mmol). The reaction was heated to 100° C. and stirred for 1 h. The reaction was then concentrated, followed by the addition of EtOAc (100 mL) and potassium fluoride (50 mL of a saturated aqueous solution). The mixture was stirred for 30 min and then filtered through a pad of Celite. The filtrate was concentrated and then dissolved in THF (80 mL) and water (80 mL). NBS (18.1 g, 102 mmol) was then added, and the reaction was stirred for 20 min at rt. The reaction mixture was poured into ethyl acetate (200 mL), washed twice with brine (50 mL), dried over Na2SO4, filtered, concentrated, and purified by silica gel chromatography to afford 4.2 g of 2-bromo-1-(6-chloropyridazin-3-yl)ethanone.

Provenance & Evidence