反应详情

To a CH2Cl2 (280 mL) solution of the title compound of Step B (24.7 g, 69.4 mmol) was added m-CPBA (77 wt %, 23.3 g, 104 mmol). After 15 h, 10% Na2S2O5 was added and the solution allowed to stir until the aqueous was Kl paper negative and extracted with CH2Cl2 (2×). The combined organic layers were washed with saturated NaHCO3 (aq.), concentrated and treated with MeOH (220 mL) and 1N NaOH (220 mL). After 15 h, the reaction was partially concentrated to remove the MeOH and acidified with 1M KHSO4 (220 mL) then extracted with CH2Cl2 (2×). The combined organic layers were washed with brine and dried to give a brown solid that was triturated with EtOAc/hexanes giving 17.6 g (74% yield) of the title compound as a white solid. 1H NMR (500 MHz, CDCl3): 7.03 (dd, J=8.5, 2.1 Hz), 1H), 6.84 (d, J=8.5 Hz, 1H), 6.64 (d, J=2.2 Hz, 1H), 4.93-4.89 (m, 1H), 4.34 (dd, J=10.1, 6.8 Hz, 1H), 4.03 (dd, J=9.9, 3.7 Hz, 1H), 1.46 (s, 9H).

1. extractionextracted with CH2Cl2 (2×)
2. washThe combined organic layers were washed with saturated NaHCO3 (aq.)
3. concentrationconcentrated
4. additiontreated with MeOH (220 mL) and 1N NaOH (220 mL)
5. waitAfter 15 h
6. concentrationthe reaction was partially concentrated
7. customto remove the MeOH
8. extractionthen extracted with CH2Cl2 (2×)
9. washThe combined organic layers were washed with brine
10. customdried
11. customto give a brown solid that