Methyl 3-aminopyrazinecarboxylate → Methyl 2-(4-fluorophenyl)imidazo[1,2-a]pyrazine-8-carboxylate

Participants

Reaction Conditions

Reaction Steps

A mixture of 2-bromo-1-(4-fluorophenyl)ethanone (30.0 g, 138 mmol) and methyl 3-aminopyrazine-2-carboxylate (21.2 g, 138 mmol) in ACN (300 mL) was heated at about 80° C. The mixture was removed from heat after about 72 h and concentrated under reduced pressure. The crude material was partitioned between saturated aqueous NaHCO3 (450 mL) and DCM (350 mL). The layers were separated and the aqueous layer was washed with additional DCM (2×250 mL). The combined organic layers were washed with water (3×350 mL) and brine (20 ml) then dried over MgSO4, filtered, and concentrated under reduced pressure to give the crude title compound (38.7 g, 45.5%) that was carried on without further purification. LC/MS (Table 1, Method h) Rt=2.26 min; MS m/z: 272.2 (M+H)+.

Provenance & Evidence