反应详情

Intermediate 6b (150 mg, 0.87 mmol) dissolved in DCM (10 mL) was cooled using an ice bath, and then treated sequentially with triethylamine (0.18 mL, 1.30 mmol) and trichloroethyl chloroformate (0.15 mL, 1.08 mmol). The mixture was stirred with cooling for 45 min, then evaporated to dryness. Residue was purified by FCC, eluting with 0-30% ethyl acetate in cyclohexane, to give the title compound as a beige solid (286 mg, 95%). LCMS (Method 3): Rt 4.25 min, m/z 348/350/352 [MH+].

1. temperaturewas cooled
2. temperaturewith cooling for 45 min
3. customevaporated to dryness
4. customResidue was purified by FCC
5. washeluting with 0-30% ethyl acetate in cyclohexane