Cesium carbonate → Tert-butyl (4-((2-((6-ethylpyrazin-2-yl)amino)pyridin-4-yl)methoxy)naphthalen-1-yl)carbamate

Beteiligte Stoffe

Reaktionsbedingungen

Reaktionsschritte

A mixture of tert-butyl (4-((2-chloropyridin-4-yl)methoxy)naphthalen-1-yl)carbamate (Intermediate C) (1050 mg, 2.73 mmol), 6-ethylpyrazin-2-amine (437 mg, 3.55 mmol), and cesium carbonate (1333 mg, 4.09 mmol) in 1,4-dioxane (15 mL) was degassed with nitrogen for 5 min. A solution of Pd2(dba)3 (125 mg, 0.136 mmol) and BINAP (170 mg, 0.273 mmol) in 1,4-dioxane (5 mL) was added, and the reaction mixture stirred at 90° C. for 6 h. The reaction mixture was allowed to cool and was stirred at room temperature for 16 h, then diluted with 10% MeOH/DCM (25 mL) and filtered through a plug of Celite, washing with additional 10% MeOH/DCM (15 mL). The solvent was removed in vacuo and the crude product was combined with MeOH (15 mL) and slurried for 3 h. The resulting orange solid was isolated by filtration, then combined with MeOH/EtOH (5 mL) solution and stirred for 72 h. Again the resulting orange solid was isolated by filtration, then acetone (20 mL) was added and the mixture was slurried for 2 h. The residual solid was filtered off, and the filtrate was evaporated to give the subtitle compound tert-butyl (4-((2-((6-ethylpyrazin-2-yl)amino)pyridin-4-yl)methoxy)naphthalen-1-yl)carbamate (360 mg, 27%); Rt 2.6 min (Method 2); m/z 472 (M+H)+ (ES+); 1H NMR δ: 1.18 (3H, t), 1.47 (9H, s), 2.63 (2H, q), 5.36 (2H, s), 6.99 (1H, d), 7.06 (1H, d), 7.36 (1H, d), 7.53-7.63 (2H, m), 7.90-8.06 (3H, overlapping m), 8.29 (1H, d), 8.36 (1H, m), 8.91 (1H, s), 8.96 (1H, s), 10.06 (1H, s).

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