Toluene → 4-(5-Chloro-2-methoxyphenyl)pyridazine

Beteiligte Stoffe

Reaktionsbedingungen

Reaktionsschritte

To an argon purged flask containing toluene (187 mL), ethanol (20.6 mL) and a 2M aqueous solution of sodium carbonate (132.3 mL) was added 4-bromopyridazine hydrobromide (Preparation 5, 15 g, 64 mmol), 5-chloro-2-methoxybenzeneboronic acid (13.4 g, 72 mmol) and tetrakis(triphenylphosphine) palladium (0) (3.2 g, 2.8 mmol). The flask was purged with argon again, then the reaction mixture heated to 110° C. for 4 hours. The mixture was filtered through Celite™ and the filtrate concentrated in vacuo. The residue was partitioned between ethyl acetate and water. The organic layer was washed with water and brine, then dried over anhydrous sodium sulfate, filtered and concentrated in vacuo. The crude residue was dissolved in ethyl acetate and extracted with a 2M aqueous solution of hydrogen chloride (×3). The aqueous layer was basified with sodium hydrogen carbonate and extracted with ethyl acetate. The organic layer was then washed with water and brine, dried over anhydrous sodium sulfate, filtered and concentrated in vacuo to afford the title compound (8 g, 58%).

Herkunft & Nachweise