反应详情

120 mg of sodium borohydride were added gradually to a mixture of 1 g of 2-methyl-2-(4-nitrophenoxymethyl)-4-oxochroman (prepared as described in Preparation 1), 10 ml of methanol and 10 ml of tetrahydrofuran, in an ice bath. The resulting reaction mixture was stirred for 30 minutes in the ice bath, after which it was stirred for a further 30 minutes at room temperature. At the end of this time, dilute aqueous hydrochloric acid was added to the reaction mixture to acidify it, and then the mixture was extracted with ethyl acetate. The organic extract was dried over anhydrous magnesium sulfate, and then the organic solvent was removed by distillation under reduced pressure. The residue was subjected to silica gel column chromatography eluted with a 10:1 by volume mixture of benzene and ethyl acetate, to afford 710 mg of the title compound as a pale yellow oily substance.

1. customThe resulting reaction mixture
2. extractionthe mixture was extracted with ethyl acetate
3. extractionThe organic extract
4. dry with materialwas dried over anhydrous magnesium sulfate
5. customthe organic solvent was removed by distillation under reduced pressure
6. washeluted with a 10:1 by volume mixture of benzene and ethyl acetate