反应详情

To a solution of 1H-indole-4-carbaldehyde (2.00 g, 13.8 mmol) in anhydrous DMF (6.5 mL) was added sodium hydride (827 mg of 60% dispersion in oil, 20.7 mmol). The mixture was stirred for 30 min at room temperature. Ethyl iodide (2.22 mL, 27.5 mmol) was then added and the reaction mixture was stirred for 12 h at room temperature. Water was added (100 mL) and the mixture was extracted with ethyl acetate (3×100 mL). Combined organic layers were washed with brine (100 mL), dried over Na2SO4, filtered and concentrated to an orange oil. Purification by column chromatography (silica gel, gradient elution of CH2Cl2 to 5% MeOH/CH2Cl2) gave the title compound (1-ethyl-1H-indole-4-carbaldehyde) (2.43 g, 99%) as a yellow oil: 1H NMR (300 MHz, DMSO-d6) δ 10.19 (s, 1H), 7.88 (d, J=8.1 Hz, 1H), 7.68-7.64 (m, 2H), 7.37-7.32 (m, 1H), 7.08 (d, J=3.0, 1H), 4.28 (q, J=7.2 Hz, 2H), 1.36 (t, J=7.2 Hz, 3H).

1. stirringthe reaction mixture was stirred for 12 h at room temperature
2. extractionthe mixture was extracted with ethyl acetate (3×100 mL)
3. washCombined organic layers were washed with brine (100 mL)
4. dry with materialdried over Na2SO4
5. filtrationfiltered
6. concentrationconcentrated to an orange oil
7. customPurification
8. washby column chromatography (silica gel, gradient elution of CH2Cl2 to 5% MeOH/CH2Cl2)