反应详情

Sodium borohydride (0.21 g, 5.5 mmol) was added to a solution of the product from Step B (1.2 g, 5.5 mmol) in MeOH (10 ml) at room temperature. After stirring for 2 h at room temperature the solvent was evaporated and a saturated aqueous solution of ammonium chloride (10 mL) was added to the residue; this mixture was extracted with ethyl acetate (3×50 mL). The combined extracts were washed with brine (10 ml), dried (MgSO4) and evaporated to a residue which was purified by chromatography (silica, 20% to 30% ethyl acetate in hexane) to give an oil (0.68 g, 56%): MS (ES) m/z 221 (M+).

1. customwas evaporated
2. additiona saturated aqueous solution of ammonium chloride (10 mL) was added to the residue
3. extractionthis mixture was extracted with ethyl acetate (3×50 mL)
4. washThe combined extracts were washed with brine (10 ml)
5. dry with materialdried (MgSO4)
6. customevaporated to a residue which
7. customwas purified by chromatography (silica, 20% to 30% ethyl acetate in hexane)