反应详情

温度

0 °C

To a suspension of 4-methoxybenzyltriphenylphosphonium chloride (419 mg, 1.0 mmol) in THF (10 mL) at 0° C. was added solid potassium tert-butoxide (224 mg, 2.0 mmol). The resultant orange-red solution was stirred for 15 min at 0° C. then cooled to −45° C. Solid compound 53 (327 mg, 1.0 mmol) was added and the reaction mixture stirred for 30 min at this temperature. To this pale yellow solution glacial acetic acid (60 μL, 1 mmol) was added and the solvent was removed in vacuo. The crude product was suspended in dichloromethane, adsorbed onto silica gel and purified by flash chromatography using hexanes-ethyl acetate (7:3) to yield a white solid (143 mg, 33%) after drying under high vacuum. 1H NMR: (400 MHz, DMSO-d6): δ 12.04 (bs, 1H), 7.27 (d, J=8.0 Hz, 2H), 7.24 (d, J=8.4 Hz, 2H), 7.18 (d, J=8.4 Hz, 2H), 6.97 (d, J=8.4 Hz, 2H), 6.88 (d, J=8.8 Hz, 2H), 6.84 (d, J=8.8 Hz, 2H), 6.53 (d, J=12.4 Hz, 2H), 6.48 (d, J=12.0 Hz, 2H), 4.90 (dd, J=9.2 and 4.4 Hz, 1H), 3.36 (dd, J=14.0 and 4.4 Hz, 1H), 3.11 (dd, J=14.0 and 8.8 Hz, 1H).

1. temperaturethen cooled to −45° C
2. stirringthe reaction mixture stirred for 30 min at this temperature
3. customthe solvent was removed in vacuo
4. custompurified by flash chromatography