反应详情

温度

-10 °C

To a solution of piperidine-1,4-dicarboxylic acid mono-tert-butyl ester (1.20 equiv; 252.61 mmol; 57.92 g) in THF (400 mL), add NMM (3 equiv; 631.52 mmol; 69.66 mL). Cool to −10° C. with a dry ice-acetone bath. Add isobutyl chloroformate (1.1 equiv; 231.56 mmol; 30.26 mL) dropwise maintaining the temperature below −5° C. After 30 min at from −5 to 10° C., add 2-amino-1-(4-fluoro-3-(trifluoromethyl)-phenyl)-ethanone hydrochloride (54.23 g; 1.00 equiv; 210.51 mmol) suspended in THF (300 mL) and stir the mixture in the bath at −5° C. for 20 min and then 1 h at RT. Partition between water and EA; wash the organic layer with water then saturated NaCl aqueous (brine), dry over anhydrous MgSO4, filter and concentrate in vacuo. Suspend the crude in MTBE and stir for 2 h. Filter the solid and dry in vacuo to give the title compound (64.44 g; 70.79%). 1H NMR (300 MHz, DMSO): 8.37-8.26 (m, 3H), 7.74-7.68 (m, 1H), 4.61 (d, J=5.5 Hz, 2H), 3.91 (d, J=12.9 Hz, 2H), 2.75-2.64 (m, 2H), 2.46-2.37 (m, 1H), 1.69-1.60 (m, 2H), 1.39 (s, 12H).

1. custom1 h
2. customat RT
3. customPartition between water and EA
4. washwash the organic layer with water
5. dry with materialsaturated NaCl aqueous (brine), dry over anhydrous MgSO4
6. filtrationfilter
7. concentrationconcentrate in vacuo
8. stirringstir for 2 h
9. filtrationFilter the solid
10. customdry in vacuo