反应详情

To a solution of the product from step 1 (0.5 g, 1.6 mmol) in TFA (1 mL) was added triethylsilane (0.5 mL, 25 mmol) at 0° C. The resulting mixture was allowed to warm to rt and stir at rt for 16 h. The mixture was poured onto 30 mL ice-water solution, neutralized with aq NaOH (2N) to pH=6-7, and then extracted with EtOAc (2×20 mL). The combined organic layers were washed with water (5×20 mL) and brine (20 mL). and dried over anhy. Na2SO4. The solvent was removed in vacuo to obtain the crude product which was purified by silica gel flash chromatography to afford the title product (0.45 g, 85%) as a solid; 1H NMR (400 MHz, CDCl3); δ 3.78 (s, 3H), 3.87 (s, 2H), 6.82 (d, J=8.8, 2H), 7.04 (d, J=8.8, 2H), 7.07 (d, J=8.8, 2H), 7.98 (d, J=8.4, 2H).

1. extractionextracted with EtOAc (2×20 mL)
2. washThe combined organic layers were washed with water (5×20 mL) and brine (20 mL)
3. customand dried over anhy
4. customThe solvent was removed in vacuo
5. customto obtain the crude product which
6. customwas purified by silica gel flash chromatography