Dimethylformamide → 2-Chloro-6,7-difluoroquinoline-3-carbaldehyde

Temperature

30 °C

Phosphoryl chloride (147.1 mL) is carefully added to DMF (32.5 mL) at 0-15° C. to prepare a solution of vilsmeier reagent in phosphoryl chloride, and the mixture is warmed to 30° C. to give clear pale yellow mixture. 3,4-difluoroacetanilide (30 g, 0.12 mol) is added to the mixture, and the resulting mixture is stirred at 80° C. for 30 min, 90° C. for 30 min, 100° C. for 18 hours, and finally 120° C. for 2 hours. The mixture is cooled to room temperature, poured onto ice-water (1500 mL) and extracted with CH2Cl2 7 times (total 3000 mL). The combined organic layer is dried over magnesium sulfate, filtered and concentrated. The brown crystal is collected and washed with CH2Cl2 to give 2-chloro-6,7-difluoroquinoline-3-carbaldehyde as a pale yellow powder.

1. customto give clear pale yellow mixture
2. waitfinally 120° C. for 2 hours
3. temperatureThe mixture is cooled to room temperature
4. additionpoured onto ice-water (1500 mL)
5. extractionextracted with CH2Cl2 7 times (total 3000 mL)
6. dry with materialThe combined organic layer is dried over magnesium sulfate
7. filtrationfiltered
8. concentrationconcentrated
9. customThe brown crystal is collected
10. washwashed with CH2Cl2

ORD record

ord-2eba717907ab4e79bb621f64b3e3d438

Source dataset

uspto-grants-2013_04

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US08410275B2