Potassium Carbonate → 4-Bromo-2-phenylpyridine

A mixture was prepared of 2,4-dibromopyridine (10 g, 42.21 mmol), phenylboronic acid (5.1 g, 42.21 mmol), and potassium carbonate (11.7 g, 84.42 mmol) in 100 mL dimethoxyethane and 40 mL of water. Nitrogen was bubbled directly into the mixture for 30 minutes. Next, tetrakis(triphenylphosphine)palladium(0) was added (244 mg, 2.11 mmol) and the mixture was heated to reflux under nitrogen overnight. The mixture was cooled and diluted with ethyl acetate and water. The layers were separated and the aqueous layer was extracted with ethyl acetate. The organic layers were washed with brine, dried over magnesium sulfate, filtered, and evaporated to a residue. The residue was purified by column chromatography eluting with 0, 2, and 5% ethyl acetate/hexanes. Obtained 4.28 g of a yellow liquid (43%).

1. customNitrogen was bubbled directly into the mixture for 30 minutes
2. additionNext, tetrakis(triphenylphosphine)palladium(0) was added (244 mg, 2.11 mmol)
3. temperaturethe mixture was heated
4. temperatureto reflux under nitrogen overnight
5. temperatureThe mixture was cooled
6. additiondiluted with ethyl acetate and water
7. customThe layers were separated
8. extractionthe aqueous layer was extracted with ethyl acetate
9. washThe organic layers were washed with brine
10. dry with materialdried over magnesium sulfate
11. filtrationfiltered
12. customevaporated to a residue
13. customThe residue was purified by column chromatography
14. washeluting with 0, 2, and 5% ethyl acetate/hexanes

ORD record

ord-607ba29de73b462b99b58bde0bcf2613

Source dataset

uspto-grants-2013_08

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US08519384B2