Phosphorus oxychloride → 2-Chloro-4-cyanopyridine

Temperature

110 °C

4-cyanopyridine-N-oxide (10.0 g) was added to phosphorus oxychloride (85 mL) and heated to 110° C. for 2.5 h. The mixture was cooled to room temperature and the excess phosphorus oxychloride removed under reduced pressure. The residue was dissolved in water and made basic with concentrated ammonia. The product was extracted into methylene chloride, dried over anhydrous magnesium sulfate and concentrated under reduced pressure. Column chromatography on silica gel (100 mL) using methylene chloride as eluent to give 7.19 g of the title compound: 1H NMR (CDCl3) δ 7.48, 7.6, 8.6.

1. temperatureThe mixture was cooled to room temperature
2. customthe excess phosphorus oxychloride removed under reduced pressure
3. dissolutionThe residue was dissolved in water
4. extractionThe product was extracted into methylene chloride
5. dry with materialdried over anhydrous magnesium sulfate
6. concentrationconcentrated under reduced pressure

ORD record

ord-997f4f9348f844eb9f2a3334e3ef40cf

Source dataset

uspto-grants-2007_02

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US07176242B2