Potassium Carbonate → 3-Bromo-5-(difluoromethoxy)pyridine

A mixture of 3-bromo-5-hydroxypyridine (Aldrich, Buchs, Switzerland, 1.394 mmol), sodium chlorodifluoroacetate (Aldrich, Buchs, Switzerland, 1.672 mmol) and potassium carbonate (2.79 mmol) in acetonitrile (10 ml) was refluxed for 4 h 45 min. The reaction was cooled and diluted with dichloromethane, washed with saturated aqueous NaHCO3, with brine, dried over Na2SO4, filtered and evaporated. The residue was taken in DMA and purified by preparative HPLC. The fractions containing product were basified with NaHCO3, concentrated and extracted with dichloromethane (2×). The combined organic layers were washed with brine, dried over Na2SO4, filtered, evaporated to give the title compound as a brown oil. (HPLC: tR 2.91 min (Method A); M+H=224, 226 MS-ES).

1. temperaturewas refluxed for 4 h 45 min
2. temperatureThe reaction was cooled
3. washwashed with saturated aqueous NaHCO3, with brine
4. dry with materialdried over Na2SO4
5. filtrationfiltered
6. customevaporated
7. custompurified by preparative HPLC
8. additionThe fractions containing product
9. concentrationconcentrated
10. extractionextracted with dichloromethane (2×)
11. washThe combined organic layers were washed with brine
12. dry with materialdried over Na2SO4
13. filtrationfiltered
14. customevaporated

ORD record

ord-8905e10dc6a74573a21004a19c46a622

Source dataset

uspto-grants-2013_07

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US08476294B2