Reacción #320662

Ecuación de reacción

2-bromo-3-hydroxypyridine

phenylboronic acid

HCl

→

3-hydroxy-2-phenylpyridine

Rendimiento 45.4%

Disolventes

toluene

ethanol

sodium hydroxide

water

Condiciones de reacción

Tratamiento posterior

1. 1
   Otrowas degassed with a stream of nitrogen
2. 2
   workup.ADDITIONThe mixture was diluted with water (50 mL) and ethyl acetate (100 mL)
3. 3
   Secadothe organic layer was dried over sodium sulfate
4. 4
   Concentraciónconcentrated
5. 5
   Otroaffording a yellow solid
6. 6
   Extracciónthe resulting solution was extracted with ethyl acetate
7. 7
   Extracciónagain was extracted with ethyl acetate
8. 8
   SecadoThe combined organic extracts were dried with sodium sulfate
9. 9
   Concentraciónconcentrated to an oily solid, which
10. 10
    Otrowas triturated with 2:1 hexane/ethylacetate

Procedimiento

A mixture of 2-bromo-3-hydroxypyridine (2.20 g, 12.6 mmol), phenylboronic acid (2.00 g, 16.3 mmol) and palladium (tetrakis)triphenylphosphine (250 mg) in toluene (30 mL), ethanol (15 mL) and 5% aqueous sodium hydroxide (15 mL) was degassed with a stream of nitrogen and stirred vigorously at 100° C. overnight. The mixture was diluted with water (50 mL) and ethyl acetate (100 mL), and the organic layer was dried over sodium sulfate and concentrated, affording a yellow solid. This material was suspended in water (100 mL), a few mL of 1N HCl was added, and the resulting solution was extracted with ethyl acetate. The aqueous layer was neutralized with saturated aqueous sodium bicarbonate, and again was extracted with ethyl acetate. The combined organic extracts were dried with sodium sulfate and concentrated to an oily solid, which was triturated with 2:1 hexane/ethylacetate, affording 0.98 g of 3-hydroxy-2-phenylpyridine.

Fuente