反应详情

To a solution of Intermediate 46a (3.43 g, 12.8 mmol), Ph3P (6.71 g, 25.6 mmol) and Et3N (7.14 mL, 51.2 mmol) in THF (75 mL) at 0° C. was added hexachloroethane (6.06 g, 25.6 mmol) and the solution stirred at RT for 4 h. The brown suspension was filtered and the solid washed with THF (10 mL). The combined organics were applied to an SCX-2 cartridge, which was washed with DCM-MeOH (1:1, 100 mL) and MeOH (100 mL). The product was eluted with 2M NH3 in MeOH; concentration in vacuo gave an off-white solid. FCC, using 1-5% [2M NH3 in MeOH] in DCM, gave the title compound as an off-white solid (1.70 g, 53%). 1H NMR (300 MHz, CDCl3): 1.66 (3H, d, J 6.8), 2.45-2.60 (4H, m), 3.63-3.76 (4H, m), 4.28 (1H, q, J 6.8), 7.21 (1H, ddd, J 10.0, 7.5, 2.3), 7.76 (1H, ddd, J 10.0, 4.9, 0.9), 8.50 (1H, ddd, J 3.9, 2.3, 0.9).

1. filtrationThe brown suspension was filtered
2. washthe solid washed with THF (10 mL)
3. washwas washed with DCM-MeOH (1:1, 100 mL) and MeOH (100 mL)
4. washThe product was eluted with 2M NH3 in MeOH
5. concentrationconcentration in vacuo
6. customgave an off-white solid