反应详情

To a suspension of sodium hydride (1.92 g, 60% in Oil) in a mixture of tetrahydrofuran (200 ml) and N,N-dimethylformamide (50 ml) was added dropwise ethyl 3-(benzyloxycarbonylamino)propionate (10 g) at 30° C. under nitrogen atmosphere, which was stirred for 30 minutes. To the reaction mixture was added methyl iodide (3 ml) and stirred for additional 6 hours. To the resulting mixture was added carefully water (5 ml), which was poured into a mixture of ethyl acetate (500 ml), n-hexane (150 ml) and water (100 ml). Organic layer was separated, washed n turn with water (100 ml×3), 1N-aqueous hydrochloric acid (100 ml), brine (100 ml), saturated sodium hydrogen carbonate in water (100 ml) and brine (100 ml×2), and dried over magnesium sulfate. Evaporation of the solvent gave a residue, which was chromatographed on silica gel (250 ml) eluting In turn with n-hexane, 10%, 50% ethyl acetate in n-hexane to give ethyl 3-(N-benzyloxycarbonyl-N-methylamino)propionate (8.32 g).

1. stirringstirred for additional 6 hours
2. customOrganic layer was separated
3. washwashed n
4. dry with materialdried over magnesium sulfate
5. customEvaporation of the solvent
6. customgave a residue, which
7. customwas chromatographed on silica gel (250 ml)
8. washeluting In turn with n-hexane, 10%, 50% ethyl acetate in n-hexane