反应详情

To a suspension of the ketone of Step 6 (800 mg, 3 mmol) in THF (10 mL) was added methyl bromoacetate (2.3 g, 15 mmol) and 1 g of Zn-copper couple. The reaction mixture was put in a sonicator at r.t. until an exotherm was observed. The reaction flask was cooled in an ice bath to keep the internal temperature below 50° C. and the mixture was stirred at r.t. for 1 hour. The reaction mixture was poured into a 2:1 mixture of saturated aqueous NH4Cl/EtOAc (100 mL) and filtered on paper. The filtrate was extracted with EtOAc, the combined organic layers were washed with brine and water, dried over Na2SO4 and concentrated. The residue was purified by silica gel chromatography eluted with 35% EtOAc in Hexanes to provide 780 mg of the title compound as a pale yellow oil.

1. customwas put in a sonicator at r.t. until an exotherm
2. temperatureThe reaction flask was cooled in an ice bath
3. customthe internal temperature below 50° C.
4. filtrationfiltered on paper
5. extractionThe filtrate was extracted with EtOAc
6. washthe combined organic layers were washed with brine and water
7. dry with materialdried over Na2SO4
8. concentrationconcentrated
9. customThe residue was purified by silica gel chromatography
10. washeluted with 35% EtOAc in Hexanes