反应详情

To a solution of 71 (22.9 mg, 3.2 μmol) in 1:1 THF/AcOH (1.4 mL) was added Zn (5.0 mg, 7.8 μmol, nanosize). The mixture was sonicated for 15 min. More Zn (5.0 mg, 7.8 μmol, nanosize) was added, followed by sonication for a further 15 min. The suspension was filtered through a celite pad, washing with EtOAc several times. The filtrates were washed with sat. NaHCO3, brine, dried over MgSO4 and concentrated under vacuum. The crude residue was passed through a short plug of silica gel eluting with hexane/EtOAc 4:1 to give 17.1 mg (99% yield) of 71a as colorless oil: 1H NMR (400 MHz, CDCl3) δ (m, 6H), 0.96 (t, J=7.9 Hz, 9H), 0.97 (d, J=6.8 Hz, 3H), 1.05 (d, J=6.8 Hz, 3H), 1.11 (s, 3H), 1.26 (s, 3H), 1.44 (s, 9H), 1.84-1.90 (m, 1H), 2.21 (dd, J=6.7 and 17.0 Hz, 1H), 2.36 (dd, J=6.7 and 17.0 Hz, 1H), 3.24-3.29 (m, 1H), 3.44-3.52 (m, 2H), 3.67 (dd, J=3.9 and 8.9 Hz, 1H), 4.36 (dd, J=3.5 and 6.5 Hz, 1H), 4.50 (d, J=12.0 Hz, 1H), 4.54 (d, J=12.0 Hz, 1H), 7.32-7.36 (m, 5H); 13C NMR (100 MHz, CDCl3) δ 5.0, 6.9, 9.7, 13.9, 20.2, 21.8, 28.0, 36.3, 40.8, 41.5, 53.7, 72.5, 72.9, 73.2, 73.6, 80.7, 127.4, 127.5, 128.2, 138.6, 171.0, 221.4; IR (film, NaCl, cm−1) 3502, 2959, 2875, 1731, 1683, 1456, 1366, 1154, 1098, 996, 739; LRMS (ESI) calcd for C30H52O6SiCl3Na [M+Na+] 559.3, found 559.3; [α]23D=−41.0 (c=0.4, CHCl3).

1. customThe mixture was sonicated for 15 min
2. customfollowed by sonication for a further 15 min
3. filtrationThe suspension was filtered through a celite pad
4. washwashing with EtOAc several times
5. washThe filtrates were washed with sat. NaHCO3, brine
6. dry with materialdried over MgSO4
7. concentrationconcentrated under vacuum