反应详情

Compound 4.3 (43.27 g, 134.9 mmol) was dissolved in ethanol (168.6 mL). To the solution was added tin (80.1 g, 674.5mmol) and the reaction was stirred at room temperature for 15 min., then cooled to 0° C. To the reaction was added 4N HCl/dioxane solution (168.6 mL, 674.5 mmol) dropwise at 0° C. Then the reaction was refluxed for 3.5 h. After cooling to room temperature, the reaction mixture was concentrated in vacuo and filtered to remove insoluble materials and the filtrate was concentrated in vacuo to give the residue. The resulting residue was purified using silica gel column chromatography (hexane/EtOAc=10/1) to give 4.4 (27.2 g). 1H NMR (400 MHz) (CDCl3) δ 7.13 (1H, d, J=2.3 Hz); 7.09 (1H, dd, J=2.4, 8.4 Hz); 6.60 (1H, d, J=8.4 Hz); 4.59 (2H, s); 4.25 (2H, q, J=7.1 Hz); 3.32(1H, s); 2.63-2.55 (2H, m); 1.68-1.57 (2H, m); 1.28 (3H, t, J=7.1 Hz); 0.95 (3H, t, J=7.4 Hz).

1. temperaturecooled to 0° C
2. temperatureThen the reaction was refluxed for 3.5 h
3. temperatureAfter cooling to room temperature
4. concentrationthe reaction mixture was concentrated in vacuo
5. filtrationfiltered
6. customto remove insoluble materials
7. concentrationthe filtrate was concentrated in vacuo
8. customto give the residue
9. customThe resulting residue was purified