反应详情

1-Methylethyl 4-[(1S)-1-({5-[2-fluoro-4-(methylthio)phenyl]-2-pyrazinyl}oxy)ethyl]-1-piperidinecarboxylate (0.334 g, 45%) was prepared as a yellow oil from 5-[2-fluoro-4-(methylthio)phenyl]-2-pyrazinol (and tautomers thereof) (prepared as in Example 161, Alternative synthesis, Step 4, 0.405 g, 1.71 mmol), crude 1-methylethyl 4-{(1R)-1-[(methylsulfonyl)oxy]ethyl}-1-piperidinecarboxylate (0.70 g, 2.32 mmol) and K2CO3 (0.48 g, 3.43 mmol) in DMF (15 mL) in a manner similar to Example 166, Step 2. The crude product was purified by chromatography on an ISCO silica gel column using 0 to 25% EtOAc/hexanes. 1H NMR (400 MHz, CDCl3): δ 8.52 (s, 1H), 8.22 (d, 1H, J=1.3 Hz), 7.85 (t, 1H, J=8.3 Hz), 7.10 (dd, 1H, Ja=8.3 Hz, Jb=1.7 Hz), 7.01 (dd, 1H, Ja=12.1 Hz, Jb=1.8 Hz), 5.15-5.05 (m, 1H), 4.89 (septet, 1H, J=6.2 Hz), 4.19 (bs, 2H), 2.80-2.65 (m, 2H), 2.50 (s, 3H), 1.85-1.65 (m, 3H), 1.40-1.15 (m, 11H); LRMS (ESI), m/z 434 (M+H).

1. customThe crude product was purified by chromatography on an ISCO silica gel column