反应详情

Stannous chloride dihydrate (20.49 g; 90.82 mmol) was added to a suspension of methyl 2-fluoro-4-{5-[4-(2-methylpiperidin-1-yl)-3-nitrophenyl]-1,2,4-oxadiazol-3-yl}benzoate, obtained in step 1, (8 g; 18.16 mmol) in EtOH (80 mL) and the resulting mixture was stirred at reflux for 3 hours. The solution was diluted with a saturated aqueous solution of NaHCO3 and extracted with EtOAc (2×). The combined organic layers were washed with brine, dried over MgSO4 and concentrated affording the title compound as a yellow solid. 1H NMR (DMSO, 400 MHz) δ 8.18-7.95 (m, 3H), 7.56-7.55 (d, J=1.77 Hz, 1H), 7.44-7.41 (m, 1H), 7.21-7.19 (d, J=8.38 Hz, 1H), 5.32 (br s, 2H), 3.94 (s, 3H), 3.21-2.92 (m, 2H), 1.88-1.22 (m, 7H), 0.88 (d, J=6 Hz, 3H). LC/MS (Method B): 411.4 (M+H)+; 417.2 (M−H)−. HPLC: Rt 4.47 min (Purity: 95.6%).

1. temperatureat reflux for 3 hours
2. extractionextracted with EtOAc (2×)
3. washThe combined organic layers were washed with brine
4. dry with materialdried over MgSO4
5. concentrationconcentrated