反应详情

A solution of carbamate 81 (542 g, 0.90 mmol) in DCM (10 mL) was treated with TFA (3 mL) at 0° C. After 20 min, the reaction mixture was warmed to ambient temperature. After 1 h, the solution was concentrated, diluted with EtOAc, washed successively with saturated aqueous NaHCO3, and brine, dried over anhydrous Na2SO4, and filtered. The aqueous phase was back-extracted with DCM and the combined organic extracts were concentrated to afford 82 (401 mg, 89%) as a light yellow-colored foam was used without further purification. 1H NMR (CDCl3, 300 MHz): δ7.31-7.26 (m, 5H), 7.00-6.95 (m, 1H), 6.65-6.60 (m, 1H), 6.49-6.47 (m, 1H), 5.14-5.08 (m, 2H), 4.41 (m, 2H), 3.95-3.92 (m, 1H), 3.83-3.72 (m, 2H), 3.40-3.29 (m, 2H), 2.79 (app q, J=5.4 Hz, 1H), 2.34-2.19 (m, 1H), 1.66 (m, 2H), 0.94 (s, 9H) ppm. Mass spectrum, m/z [502.6] (M+H)+.

1. waitAfter 1 h
2. concentrationthe solution was concentrated
3. additiondiluted with EtOAc
4. washwashed successively with saturated aqueous NaHCO3, and brine
5. dry with materialdried over anhydrous Na2SO4
6. filtrationfiltered
7. extractionThe aqueous phase was back-extracted with DCM
8. concentrationthe combined organic extracts were concentrated