Toluene → 5-(Pyridazin-3-yl)pyridin-2-amine

Beteiligte Stoffe

Reaktionsbedingungen

Reaktionsschritte

To a sealed flask were added 5-(4,4,5,5-tetramethyl-1,3,2-dioxaborolan-2-yl)pyridin-2-amine 145-1 (1.54 g, 7 mmol), 3-chloropyridazine 145-2 (0.8 g, 7 mmol), Pd(PPh3)4 (500 mg, 0.7 mmol), toluene (50 mL), ethanol (12 mL) and 2M Na2CO3 (11 mL). The reaction mixture was bubbled with nitrogen for 2 minutes and stirred at 90° C. for 10 hours. After cooled to room temperature, the solvents were evaporated and the residue was redissolved in dichloromethane (200 ml) and treated with 1M HCl aqueous solution (50 mL). The two layers were separated and the aqueous layer was treated with 10% NaOH aqueous solution to adjust the pH to around 13. The resulting solution was evaporated and the remaining solid was exacted with ethyl acetate (100 mL×3). The combined organic phases were concentrated to give 5-(pyridazin-3-yl)pyridin-2-amine 145-3 as dark brown solid. MS m/z 173.1 (M+1).

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