反应详情

Combine 2-nitro-meta-xylene (5 mL, 0.037 mol), N,N-dimethylformamide dimethylacetal (5.4 mL, 1.1 eq) and N,N-dimethylformamide (60 mL) in a flask and reflux under nitrogen for 2 days. Let cool to room temperature then concentrate to approximately one-half volume. Add methanol (40 mL) and trimethylsilylchloride (6.6 mL, 1.4 eq). Reflux overnight. Dilute with ethyl acetate after cooling to room temperature then extract with saturated sodium bicarbonate followed by brine. Dry over magnesium sulfate, filter and concentrate. Purification by column chromatography (9:1 Hexanes:ethyl acetate) gives 1.15 g (14%) product as a light yellow oil. 1H NMR (400 MHz, DMSO-d6) δ 2.23 (s, 3H), 2.80 (d, J=5.36 Hz, 2H), 3.19 (s, 6H), 4.45 (m, 1H), 7.32 (m, 2H), 7.42 (m, 1H).

1. concentrationthen concentrate to approximately one-half volume
2. temperatureReflux overnight
3. temperatureafter cooling to room temperature
4. extractionthen extract with saturated sodium bicarbonate
5. dry with materialDry over magnesium sulfate
6. filtrationfilter
7. concentrationconcentrate
8. customPurification by column chromatography (9:1 Hexanes:ethyl acetate)