反应详情

To a mixture of the amine 7 (1.50 g, 3.79 mmol) in dry THF (15 mL) were added Et3N (1.65 mL, 11.75 mmol), and then a solution of benzyl chloroformate (CbzCl, 0.59 mL, 4.17 mmol) in dry THF (4 mL) at 0° C. The resulting white suspension was allowed to warm to rt and stirred for 5 h, then diluted with DCM and water. The aqueous phase was extracted with DCM (2×), and the combined organic layers were washed with 10% HCl and sat. NaHCO3, dried (MgSO4), filtered and concentrated in vacuo. Flash chromatography (SiO2, 8:2, hexanes/EtOAc) afforded 1.45 g (72%) of the title compound as a yellow oil. 1H NMR (300 MHz, CDCl3) δ 7.75-7.65 (m, 4 H), 7.50-7.28 (m, 11 H), 5.70-5.55 (m, 1 H), 5.40 (dd, 1 H, J=15.4, 6.2 Hz), 5.11 (s, 2 H), 4.58 (m, 1 H), 4.21 (m, 1 H), 3.71 (t, 2 H, J=6.6 Hz), 2.30 (q, 2 H, J=6.6 Hz), 1.67 (m, 1 H), 1.40-1.22 (m, 2 H), 1.07 (s, 9 H), 0.92 (m, 6 H); HRMS (ESI) m/z calcd for C33H43NO3SiNa 552.2910. found 552.2930.

1. customat 0° C
2. extractionThe aqueous phase was extracted with DCM (2×)
3. washthe combined organic layers were washed with 10% HCl and sat. NaHCO3
4. dry with materialdried (MgSO4)
5. filtrationfiltered
6. concentrationconcentrated in vacuo