反应详情

Under an atmosphere of N2, lithium bis(trimethylsilyl)amide solution (10.6 ml, 10.6 mmol, 1.0M in THF) was added dropwise to a solution of methoxy methyltriphenyl phosphonium chloride (3.64 g, 10.6 mmol) in 15 ml THF at 0° C. After 15 min, this solution was added to a solution of the product of STEP 5 (1.95 g, 7.08 mmol) in 15 ml THF at 0° C. The reaction was stirred for 1 h and quenched with H2O. The aqueous layer was extracted with dichloromethane. The combined organic layers were washed with H2O, brine, dried with Na0.2SO4, filtered and concentrated. The residue was purified by chromatography (SiO2, CH2Cl2/MeOH/NH4OH=95/5/0.1) to yield an oil. It was dissolved in 40 ml THF and 40 ml 1.0 N aqueous HCl solution. The reaction was stirred at 25° C. for 2 h. Potassium carbonate powder was added to neutralize the reaction mixture. The solvent was evaporated and residue was extracted with ethyl acetate. The organic layer was washed with brine, dried with MgSO4, and concentrated to give 1.6 g of product. The 1H NMR spectrum of the product was consistent for the proposed structure.

1. customquenched with H2O
2. extractionThe aqueous layer was extracted with dichloromethane
3. washThe combined organic layers were washed with H2O, brine
4. customdried with Na0.2SO4
5. filtrationfiltered
6. concentrationconcentrated
7. customThe residue was purified by chromatography (SiO2, CH2Cl2/MeOH/NH4OH=95/5/0.1)
8. customto yield an oil
9. stirringThe reaction was stirred at 25° C. for 2 h
10. customThe solvent was evaporated
11. extractionresidue was extracted with ethyl acetate
12. washThe organic layer was washed with brine
13. dry with materialdried with MgSO4
14. concentrationconcentrated