反应详情

Ethyl 1,4-dioxaspiro[4,5]decane-8-carboxylate (6.28 g, 29.3 mmol) obtained in Step 1 was dissolved in THF, and N,O-dimethylhydroxylamine hydrochloride (4.30 g, 44.1 mmol) was added thereto, followed by stirring. In an atmosphere of argon at −30° C., a 2.0 mol/L solution of isopropylmagnesium chloride in THF (44.1 mL, 88.2 mmol) was added dropwise to the reaction mixture, followed by stirring at −5° C. for 1 hour. Water was added to the reaction mixture, followed by extraction with chloroform. The organic layer was washed with a saturated aqueous solution of sodium chloride and dried over anhydrous magnesium sulfate, and then the solvent was distilled away under reduced pressure. The resulting residue was purified through silica gel column chromatography (ethyl acetate) to afford N-methoxy-N-methyl-1,4-dioxaspiro[4,5]decane-8-carboxamide (6.61 g, 99%).

1. stirringby stirring at −5° C. for 1 hour
2. extractionfollowed by extraction with chloroform
3. washThe organic layer was washed with a saturated aqueous solution of sodium chloride
4. dry with materialdried over anhydrous magnesium sulfate
5. distillationthe solvent was distilled away under reduced pressure
6. customThe resulting residue was purified through silica gel column chromatography (ethyl acetate)