反应详情

To a solution of 2-methoxyimino-4-oxo-pentanoic acid ethyl ester (2.62 g, 14 mmol) in DMF (30 mL) is added potassium carbonate (2.5 g, 18.2 mmol) followed by 1-iodo-2-methyl-propane (1.62 mL, 14 mmol) and the mixture is stirred at ambient temperature overnight. Additional 1-iodo-2-methyl-propane (0.8 mL, 7 mmol) is added and the mixture is stirred at 60° C. for 1 hour. The reaction mixture is diluted with EtOAc and is adjusted to pH 3 with 1N HCl. The organic layer is washed with brine, dried (MgSO4), filtered, and concentrated under reduced pressure. The residue is purified by column chromatography (0 to 20% EtOAc in hexanes) to give the title compound as a colorless oil (1 g, 29%). 1H NMR (400 MHz, CDCl3) δ 4.33 (q, 2H), 4.06 (s, 3H), 4.03 (dd, 1H), 2.07 (s, 3H), 1.88 (m, 1H), 1.58 (m, 1H), 1.43 (m, 1H), 1.37 (t, 3H), 0.89 (d, 6H).

1. stirringthe mixture is stirred at 60° C. for 1 hour
2. washThe organic layer is washed with brine
3. dry with materialdried (MgSO4)
4. filtrationfiltered
5. concentrationconcentrated under reduced pressure
6. customThe residue is purified by column chromatography (0 to 20% EtOAc in hexanes)