Sodium Carbonate → tert-butyl 4-(3-(4-aminophenoxy)pyrazin-2-yl)-5,6-dihydropyridine-1(2H)-carboxylate

Participants

Reaction Conditions

Reaction Steps

Into a sealed 150-mL flask were placed 4-(3-chloropyrazin-2-yloxy)aniline (2 g, 9 mmol) (see Step 1, Example 215), tert-butyl 4-(4,4,5,5-tetramethyl-1,3,2-dioxaborolan-2-yl)-5,6-dihydropyridine-1(2H)-carboxylate (4.19 g, 13.5 mmol), trans-dichlorobis-(triphenylphosphine)palladium (II) (0.5 g, 0.72 mmol), sodium carbonate (4.78 g, 45.1 mmol) and 30 mL of 4:1 DME-water. After the mixture was degassed for 5 min, the reaction was stirred at 80° C. for 18 h. The cooled reaction was diluted with CH2Cl2 and washed with aqueous saturated NaHCO3 solution; the aqueous layer was back-extracted with CH2Cl2 (2×). The organic extracts were combined, dried (MgSO4), filtered, and concentrated in vacuo. Flash column chromatography (20% to 60% EtOAc/Hexanes) afforded tert-butyl 4-(3-(4-aminophenoxy)pyrazin-2-yl)-5,6-dihydropyridine-1(2H)-carboxylate) as a cream solid. MS (ESI, pos. ion) m/z: 369.0 (M+1).

Provenance & Evidence