反应详情

Step 2 Trifluoromethanesulfonic anhydride (0.613 mL, 3.63 mmol) was added dropwise to a solution of 8-methyl-2-phenylchroman-7-ol (671 mg, 2.79 mmol) in DCM (10 mL) and pyridine (10 mL) at 0° C. After 30 min, the mixture was diluted with EtOAc (70 mL), washed with water (2×30 mL) and brine (30 mL), dried and concentrated. The residue was purified by column chromatography (eluting with a gradient from 95:5 to 85:15 hexane-EtOAc) to give 8-methyl-2-phenylchroman-7-yl trifluoromethanesulfonate as colorless liquid (925 mg, 89%). 1H NMR (400 MHz, chloroform-d) δ 7.28-7.61 (5H, m), 6.97 (1H, d, J=8.58 Hz), 6.79 (1H, d, J=8.58 Hz), 5.11 (1H, dd, J=10.23, 2.31 Hz), 2.99 (1H, ddd, J=16.73, 11.11, 5.83 Hz), 2.68-2.88 (1H, m), 2.17-2.32 (4H, m), 1.88-2.12 (1H, m). Mass spectrum m/z 390.0 (M+H)+.

1. washwashed with water (2×30 mL) and brine (30 mL)
2. customdried
3. concentrationconcentrated
4. customThe residue was purified by column chromatography (
5. washeluting with a gradient from 95:5 to 85:15 hexane-EtOAc)