Sodium Carbonate → 4-(3-Amino-pyrido[2,3-b]pyrazin-6-yl)-2-methoxy-phenol

Beteiligte Stoffe

Reaktionsbedingungen

Reaktionsschritte

To a suspension of 1.13 g 6-Chloro-pyrido[2,3-b]pyrazin-3-ylamine (5.94 mmol; 1 eq) and 1.67 g 2-Methoxy-4-(4,4,5,5-tetramethyl-[1,3,2]dioxaborolan-2-yl)-phenol (6.55 mmol; 1.1 eq.) in ethylene glycol dimethyl ether (45 mL) under Ar, a solution of 6.29 g sodium carbonate (59.3 mmol; 10 eq.) in water (20 mL) and a suspension of 378 mg FluoroFlash catalyst (0.24 mmol; 0.04 eq.) in undecafluoro(trifluoromethyl)cyclohexane (45 mL) were added. The mixture was heated to 75° C. for 5 hours. Additional 0.76 g (2.97 mmol; 0.5 eq) of 2-Methoxy-4-(4,4,5,5-tetramethyl-[1,3,2]dioxaborolan-2-yl)-phenol were added and the resulting mixture was stirred at 75° C. for 7.5 hours. After cooling to room temperature, the aqueous and organic phase were separated from the fluorous phase and concentrated in vacuo. The residue was dissolved in methanol and methylene dichloride and filtered. The black solution was again concentrated in vacuo. The residue was taken up in water and the resulting solution was neutralized with 1 N HCl whereas the product crystallizes. The brown solid was filtered of, washed with water and dried in vacuo to afford 1.5 g (80.2% yield) of 4-(3-Amino-pyrido[2,3-b]pyrazin-6-yl)-2-methoxy-phenol.

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