Quinoline → 2,3-Dichloro-5-nitropyridine

Temperature

120 °C

A 2 L flask with mechanical stirrer and thermocouple was charged with POCl3 (200 g, 1.30 mol). The flask was cooled in an ice bath to an internal temperature of 0–5° C. as quinoline (84 g, 0.65 mol) was added. The product of Example 2A (227 g, 1.30 mol) was added in portions, so as to maintain the reaction temperature below 10° C. The cold bath was removed, and the mixture was warmed to 120° C. for 90 minutes. The temperature was decreased to 100° C. and the reaction mixture was quenched by addition of water (500 mL) maintaining the internal temperature between 100–110° C. After complete addition, the mixture was cooled in ice to 0–5° C. for 1 hour and filtered. The filter cake was washed with cold water and dried under vacuum at 40° C. to provide the title compound. 1H NMR (CDCl3, 300 MHz) δ 8.39 (d, J=3 Hz, 1H), 9.16 (d, J=3 Hz, 1H).

1. additionwas added
2. temperatureso as to maintain the reaction temperature below 10° C
3. customThe cold bath was removed
4. customwas decreased to 100° C.
5. customthe reaction mixture was quenched by addition of water (500 mL)
6. temperaturemaintaining the internal temperature between 100–110° C
7. additionAfter complete addition
8. temperaturethe mixture was cooled in ice to 0–5° C. for 1 hour
9. filtrationfiltered
10. washThe filter cake was washed with cold water
11. customdried under vacuum at 40° C.

ORD record

ord-56073b2ca82343608754e95be4ff7a7f

Source dataset

uspto-grants-2008_04

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US07354937B2