Dimethylformamide dimethyl acetal → 4-Bromo-5-methoxy-2-nitrobenzaldehyde

温度

120 °C

The crude 1-bromo-2-methoxy-4-methyl-5-nitrobenzene (2.6 g, 11 mmol) was dissolved in N,N-dimethylformamide (15 mL) and N,N-dimethylformamide dimethylacetal (5 mL, 38 mmol) was added. The reaction was heated to 120° C. for 18 hours. The reaction was cooled to room temperature and the mixture was added directly to a 0° C. suspension of sodium periodate (12.2 g, 57.2 mmol) in water (20 mL) and N,N-dimethylformamide (5 mL). The reaction was stirred at 0° C. for 2 hours, then allowed to warm to room temperature and stir for another 6 hours. The reaction mixture was filtered, rinsing with ethyl acetate, toluene, and water. The filtrate was extracted with ethyl acetate (3×). The combined organics were washed with water and brine, dried over sodium sulfate, filtered, and concentrated. Purification by flash column chromatography (0-50% ethyl acetate/heptanes) gave the title compound (550 mg, 19%) as a pale yellow solid. 1H NMR (400 MHz, CDCl3, δ): 10.47 (s, 1 H), 8.41 (s, 1 H), 7.35 (s, 1 H), 4.05 (s, 3 H).

1. temperatureThe reaction was cooled to room temperature
2. additionthe mixture was added directly to a 0° C.
3. temperatureto warm to room temperature
4. stirringstir for another 6 hours
5. filtrationThe reaction mixture was filtered
6. washrinsing with ethyl acetate, toluene, and water
7. extractionThe filtrate was extracted with ethyl acetate (3×)
8. washThe combined organics were washed with water and brine
9. dry with materialdried over sodium sulfate
10. filtrationfiltered
11. concentrationconcentrated
12. customPurification by flash column chromatography (0-50% ethyl acetate/heptanes)

ORDレコード

ord-b97b8f91ff104853b495473e15ccc6ed

出典データセット

uspto-grants-2014_08

DOI

10.6084/m9.figshare.5104873.v1

特許番号

US08802688B2