反应详情

A solution of compound 2 (11.0 g, 71.3 mmol) in THF (80 mL) was treated with a 1.6 M solution of n-BuLi in hexane (58 mL, 92.8 mmol) dropwise at 0° C. for 20 min. After 30 min, paraformaldehyde (6.4 g) was added to the reaction mixture at 0° C. After 5 h, the reaction mixture was quenched with aq NH4Cl at 0° C. and diluted with EtOAc (200 mL) and washed with aq NH4Cl and brine. The organic layer was dried over MgSO4 and concentrated. The residue was purified with 20% EtOAc in hexanes by silica get column chromatography to give 8.15 g of compound 3 (44.2 mmol, 62% yield): 1H NMR (CDCl3) δ 4.63 (t, J=3.4 Hz, 1H), 4.22 (t, J=2.1 Hz, 2H), 3.91˜3.76 (m, 2H), 3.59˜3.46 (m, 2H), 2.51 (tt, J=7.1, 2.2 Hz, 2H), 1.86˜1.46 (m, 6H).

1. waitAfter 5 h
2. customthe reaction mixture was quenched with aq NH4Cl at 0° C.
3. additiondiluted with EtOAc (200 mL)
4. washwashed with aq NH4Cl and brine
5. dry with materialThe organic layer was dried over MgSO4
6. concentrationconcentrated
7. customThe residue was purified with 20% EtOAc in hexanes by silica
8. customget column chromatography