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

Beteiligte Stoffe

Reaktionsbedingungen

Reaktionsschritte

Dioxane (125 mL) was added to tert-butyl (4-((2-chloropyridin-4-yl)methoxy)naphthalen-1-yl)carbamate (Intermediate C) (9.6 g) and the mixture stirred at 20° C. Cesium carbonate (2 eq, 16.3 g) and 2-amino-6-ethylpyrazine (1.5 eq, 4.8 g) were added to the stirred mixture at ° C. Argon was purged through the reaction mixture. Tris(dibenzylideneacetone)dipalladium(0) (0.05 eq, 1.14 g) and racemic BINAP (0.10 eq, 1.56 g) were added to the reaction mixture. The mixture was stirred for an additional 15 min at 20° C. The mixture was heated to 90° C. at a rate of 1.5 K/min then stirred for 12 h at 90° C. The mixture was cooled to 20° C. and stirring continued for an additional 6 h. The heterogeneous mixture was filtered over Celite, and the filter washed with dioxane (twice 5 mL). The filtrate was concentrated in vacuo at 20 mbar and 50° C. The residue was dissolved in ethanol (150 mL). Spontaneous crystallization occurred. The heterogeneous mixture was stirred for 3 h at 22° C. The precipitate was filtered and washed with ethanol (10 mL). The product was dried in vacuo at 50° C. for 20 h to give tert-butyl (4-((2-((6-ethylpyrazin-2-yl)amino)pyridin-4-yl)methoxy)naphthalen-1-yl)carbamate (9.05 g, 76.8%).

Herkunft & Nachweise