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19a) 4- (6-BROMO-PYRAZIN-2-YI)-MORPHOLINE PBr3 (11 g, 36.9 mmol, 5.5 eq) is added to 2, 6-dichloro-pyrazine (1.0 g, 6.7 mmol, 1 eq) at rt and heated to 150 °C for 24 h. This solution is dried in vacuum and the residue is dissolved in CH2CI2 (50 mL). The organics are washed with H20, brine and dried. Morpholine is added to this solution dropwise at 0 °C and warmed to rt in 5 h. The solution is washed with H20 and brine. Chromatography (SiO2, 10-60percent EtOAc-hexanes gradient elution) provides product 4-(6-BROMO-PYRAZIN-2-YL)-MORPHOLINE (0.5 g, 31 percent). MS/ESI, M+1 = 246.01, H NMR (400 MHz, CDCI3) 8 7.99 (s, 1 H), 7.95 (s, 1 H), 3.82 (t, J = 4.0 Hz, 4H), 3.58 (t, J = 4.0 Hz, 4H).