反应详情

To a solution of ethyl 4-oxopiperidine-3-carboxylate (180.0 g, 0.87 mol, 1.0 eq.) in DCM (2.7 L) was added Et3N (352.14 g, 3.48 mol, 4.0 eq.) dropwise at 15° C. and stirred for 30 min followed by addition of (BOC)2O (210.0 g, 0.96 mol, 1.10 eq.) maintaining the temperature below 10° C. The resulted mixture was stirred at rt overnight, and concentrated to give a crude product that was stirred with hexane (3.5 L) for 1 h and filtered. The filtered cake was washed with hexanes. The combined organic phase was concentrated to furnish the title compound (226.0 g, 0.83 mol, 95.4%).

1. temperaturemaintaining the temperature below 10° C
2. stirringThe resulted mixture was stirred at rt overnight
3. concentrationconcentrated
4. customto give a crude product that
5. filtrationfiltered
6. washThe filtered cake was washed with hexanes
7. concentrationThe combined organic phase was concentrated