反应详情

(R)-7-[3-Amino-4-(2,4,5-trifluoro-phenyl)-butanoyl]-3-trifluoromethyl-5,6,7,8-tetrahydroimidazo[1,5-a]pyrazine-1-carboxylic acid hydrochloride 1 (1.02 g, 2.1 mmol) was dissolved in 30 mL of methanol followed by addition of aqueous sodium hydroxide (2.1 mL, 2.1 mmol). The reaction was stirred for 15 minutes. The reaction mixture was concentrated under reduced pressure and the resulting solid was dissolved in 15 mL of the solvent mixture of dichloromethane/methanol (v:v=1:3). The mixture was filtered and concentrated under reduced pressure to obtain the title compound (R)-7-[3-amino-4-(2,4,5-trifluorophenyl)butanoyl]-3-trifluoromethyl-5,6,7,8-tetrahydro-imidazo[1,5-a]pyrazine-1-carboxylic acid 3 (943 mg, 100%) as a white solid. HPLC: 99.89%. MS m/z (ESI): 451.2 [M+1]. 1H NMR (400 MHz, CD3OD, ppm): δ 7.32-7.41 (m, 1H), 7.11-7.21 (m, 1H), 5.00-5.07 (m, 2H), 4.16-4.24 (m, 2H), 4.05-4.08 (m, 1H), 3.85-3.97 (m, 2H), 3.05-3.17 (m, 2H), 2.91-2.93 (m, 2H).

1. concentrationThe reaction mixture was concentrated under reduced pressure
2. dissolutionthe resulting solid was dissolved in 15 mL of the solvent mixture of dichloromethane/methanol (v:v=1:3)
3. filtrationThe mixture was filtered
4. concentrationconcentrated under reduced pressure