Hydrochloric Acid → 3-Chloro-6-phenoxypyridazine

Temperature

90 °C

A mixture of 3,6-dichloropyridazine (1.0 g, 5.23 mmol), phenol (0.50 g, 5.31 mmol), potassium carbonate (2.90 g, 20.98 mmol), and copper(I) iodide (0.59 g, 3.09 mmol) in dimethylsulfoxide (3.6 mL, 1.45 M) was heated to 90° C. overnight. After this time, the reaction was cooled to 25° C. and then poured into a 2N aqueous hydrochloric acid solution (75 mL) rinsing with water. The resulting mixture was filtered through filter paper and diluted with a saturated aqueous sodium chloride solution followed by extraction with ethyl acetate (150 mL). The organics were washed with a saturated aqueous sodium chloride solution (1×75 mL), dried over magnesium sulfate, filtered and concentrated in vacuo. Silica gel column chromatography (AnaLogix, 80 g, 5-24% ethyl acetate/hexanes) afforded 3-chloro-6-phenoxy-pyridazine (1.01 g, 93%) as a yellow solid. 1H-NMR (300 MHz, DMSO-d6) δ ppm 7.14-7.35 (m, 3H), 7.47 (t, J=7.5 Hz, 2H), 7.59 (d, J=9.2 Hz, 1H), 7.96 (d, J=9.2 Hz, 1H).

1. temperatureAfter this time, the reaction was cooled to 25° C.
2. washrinsing with water
3. filtrationThe resulting mixture was filtered
4. filtrationthrough filter paper
5. additiondiluted with a saturated aqueous sodium chloride solution
6. extractionfollowed by extraction with ethyl acetate (150 mL)
7. washThe organics were washed with a saturated aqueous sodium chloride solution (1×75 mL)
8. dry with materialdried over magnesium sulfate
9. filtrationfiltered
10. concentrationconcentrated in vacuo

ORD record

ord-292315c5007d4d9a9bb89eccaa890d86

Source dataset

uspto-grants-2012_09

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US08258134B2