反应详情

The reaction and work up was conducted as described in the preparation of compound 420. Starting compounds were compound 424 (2.41 g, 9.8 mmol) in 7 mL dry THF, 3,4-dihydro-2H-pyran (0.99 mL, 10.8 mmol) and p-toluenesulfonic acid (37 mg, 0.19 mmol). The crude product was purified by flash chromatography using EtOAc/petroleum ether 1:4 as the eluent to afford the title compound as a pale yellow oil.

1. customThe reaction and work
2. customThe crude product was purified by flash chromatography