反应详情

温度

90 °C

A 100 mL round bottom flask was charged with tert-butyl 4-(3-amino-5-bromopyrazin-2-yl)piperazine-1-carboxylate (8.37 g, 0.0234 mol), ethyl 3-bromo-2-oxopropanoate (13.6 g, 0.070 mol) and EtOH (50 mL). The mixture was stirred at 90° C. for 6 h. Reaction progress was monitored by LC-MS. Work-up: the reaction mixture was filtered. The collected solid was washed with ethyl ether, to afford 5.7 g (56%) of ethyl 5-bromo-8-(piperazin-1-yl)imidazo[1,2-a]pyrazine-2-carboxylate hydrobromide. 1H NMR (300 MHz, DMSO-d6) δ: 8.43 (s, 1H), 7.73 (s, 1H), 4.37-4.32 (m, 6H), 3.16 (br, 4H), 1.34 (t, J=6.9 Hz, 3H).

1. customReaction progress
2. filtrationthe reaction mixture was filtered
3. washThe collected solid was washed with ethyl ether