反应详情

温度

0 °C

(2E)-5-(tert-Butyloxycarbonylamino)-5-methylhex-2-enoic acid (5.00 g ; 20.6 mmol) was dissolved in tetrahydrofuran (70 ml). Methyl iodide (10.3 ml; 164 mmol) was added and the solution was cooled to 0° C. Sodium hydride (60% in oil) (2.07 g; 61.6 mmol) was added in portions and the solution was stirred at room temperature for four days. Ethyl acetate (70 ml) and water (60 ml) was added dropwise and the solvent was removed in vacuo. The crude product was dissolved in water (40 ml) and ether (40 ml). The organic phase was washed with a saturated aqueous solution of sodium hydrogencarbonate (30 ml). The aqueous phases were mixed and 5% aqueous citric acid was added to pH 3. The aqueous phase was extracted with ethyl acetate (4×50 ml). The organic phase was washed with water (2×40 ml), an aqueous solution of sodium thiosulfate (5%; 40 ml), water (40 ml), dried over MgSO4 and the solvent was removed in vacuo. The residue was dissolved in ethyl acetate (45 ml) and washed with an aqueous solution of sodium hydrogensulfate (10%; 3×30 ml), dried over MgSO4 and concentrated in vacuo to give 4.00 g of (2E)-5-(N-(tert-butoxycarbonyl)-N-methylamino)-5-methylhex-2-enoic acid.

1. customthe solvent was removed in vacuo
2. dissolutionThe crude product was dissolved in water (40 ml)
3. washThe organic phase was washed with a saturated aqueous solution of sodium hydrogencarbonate (30 ml)
4. additionThe aqueous phases were mixed
5. addition5% aqueous citric acid was added to pH 3
6. extractionThe aqueous phase was extracted with ethyl acetate (4×50 ml)
7. washThe organic phase was washed with water (2×40 ml)
8. dry with materialan aqueous solution of sodium thiosulfate (5%; 40 ml), water (40 ml), dried over MgSO4
9. customthe solvent was removed in vacuo
10. dissolutionThe residue was dissolved in ethyl acetate (45 ml)
11. washwashed with an aqueous solution of sodium hydrogensulfate (10%; 3×30 ml)
12. dry with materialdried over MgSO4
13. concentrationconcentrated in vacuo