反应详情

3-Trifluoromethyl-imidazo[1,5-a]pyrazine 1j (12.0 g, 64.2 mmol) was dissolved in 150 mL of anhydrous ethanol, then 10% Pd/C (500 mg) was added to the solution. The reaction mixture was stirred at room temperature under a hydrogen atmosphere for 12 hours. The reaction solution was filtered through a pad of coarse silica gel and the filtrate was concentrated under reduced pressure to obtain the title compound 3-trifluoromethyl-5,6,7,8-tetrahydro-imidazo[1,5-a]pyrazine 1k (12.2 g, yield 99%) as a brown solid. 1H NMR (400 MHz, CDCl3, ppm): δ 6.84 (s, 1H), 4.10 (m, 4H), 3.26 (m, 2H), 1.81 (s, 1H).

1. filtrationThe reaction solution was filtered through a pad of coarse silica gel
2. concentrationthe filtrate was concentrated under reduced pressure