反应详情

To a solution of benzyl 4-[(trimethylsilyl)oxy]-3,6-dihydropyridine-1(2H)-carboxylate (800 g, 2.61 mol) in acetonitrile was added Selectfluor™ (932.8 g, 2.63 mol) in small portions under nitrogen at 0° C. After the addition was complete, the reaction mixture was allowed to warm to room temperature and stirred overnight. TLC (EtOAc/petroleum ether=1:1) indicated the reaction was complete, and the solvent was removed in vacuo. The residue was triturated with ethyl acetate (5 L, 3 L) for 30 min and filtered. The filtrate was concentrated and the syrup was purified by column chromatography (EtOAc/petroleum ether=1:10 to 2:3) to afford benzyl 3-fluoro-4-oxopiperidine-1-carboxylate. 1H NMR (600 MHz, CDCl3-D6) 7.40-7.30 (m, 5H); 5.20 (s, 2H); 5.00-4.70 (d, 1H); 5.20-4.90 (d, 1H); 4.30-4.20 (m, 1H); 3.40-3.20 (m, 2H); 2.50 (s, 2H).

1. additionAfter the addition
2. customthe solvent was removed in vacuo
3. customThe residue was triturated with ethyl acetate (5 L, 3 L) for 30 min
4. filtrationfiltered
5. concentrationThe filtrate was concentrated
6. customthe syrup was purified by column chromatography (EtOAc/petroleum ether=1:10 to 2:3)