反应详情

1,2,3,4,11,11a-Hexahydro-2-benzyl-4-methyl-pyrazino[1,2-b]isoquinolin-6-one (from Isomer B, 93 mg, 0.30 mmol) and 10% palladium on carbon (40 mg) in EtOAc (9 ml) was stirred under a balloon of hydrogen. After 3 days the reaction was about 60% complete by HPLC. The catalyst was filtered off and then fresh catalyst added. After stirring an additional day under a balloon of hydrogen, the reaction was filtered through Celite® rinsing with EtOAc and methanol to afford 56 mg of crude product. Column purification (Chiralcel OD, 15% 1/1 MeOH/EtOH in hexanes) afforded pure (4R,11aR)-1,2,3,4,11,11a-hexahydro-4-methyl-pyrazino[1,2-b]isoquinolin-6-one (18 mg, 28% yield). MS (ESI) 217 (M+H). Further elution afforded pure (4S,11aS)-1,2,3,4,11,11a-hexahydro-4-methyl-pyrazino[1,2-b]isoquinolin-6-one (16 mg, 25% yield). MS (ESI) 217 (M+H).

1. filtrationThe catalyst was filtered off
2. additionfresh catalyst added
3. filtrationthe reaction was filtered through Celite®
4. washrinsing with EtOAc and methanol
5. customto afford 56 mg of crude product
6. customColumn purification (Chiralcel OD, 15% 1/1 MeOH/EtOH in hexanes)