反应详情

To a stirred solution of 2-hydroxy-2-(3-(5-phenyl-4-(trifluoromethyl)isoxazol-3-yl)-4,5-dihydronaphtho[1,2-c]isoxazol-7-yl)acetic acid (Preparation 131B isomer 1, 230 mg, 0.50 mmol) in dichloromethane (5 mL) and MeOH (5 mL) was added (trimethylsilyl)diazomethane (0.42 mL, 0.84 mmol) dropwise at 0° C. The excess reagent was quenched by the slow addition of glacial AcOH (0.02 mL, 0.34 mmol) at 0° C. and the solution was concentrated. The resulting residue was mixed with ethyl acetate (30 mL). The ethyl acetate solution was washed with sat. aq. sodium bicarbonate (10 mL) and brine (10 mL), dried (sodium sulfate), filtered through a pad of silica gel, and concentrated. The resulting residue was purified by silica gel flash chromatography (ethyl acetate:hexane 45%) to yield methyl 2-hydroxy-2-(3-(5-phenyl-4-(trifluoromethyl)isoxazol-3-yl)-4,5-dihydronaphtho[1,2-c]isoxazol-7-yl)acetate (230 mg, 0.489 mmol, 97% yield) as an oil: LC/MS M+1=471.09; 1H NMR (400 MHz, CDCl3) δ ppm 8.04 (1H, d, J=8.58 Hz), 7.76 (2H, d, J=7.26 Hz), 7.50-7.67 (3H, m), 7.41-7.49 (2H, m), 5.23 (1H, d, J=5.28 Hz), 3.82 (3H, s), 3.03-3.15 (4H, m).

1. concentrationthe solution was concentrated
2. additionThe resulting residue was mixed with ethyl acetate (30 mL)
3. washThe ethyl acetate solution was washed with sat. aq. sodium bicarbonate (10 mL) and brine (10 mL)
4. dry with materialdried (sodium sulfate)
5. filtrationfiltered through a pad of silica gel
6. concentrationconcentrated
7. customThe resulting residue was purified by silica gel flash chromatography (ethyl acetate:hexane 45%)