Reacción #453041

Ecuación de reacción

5-bromo-3-pyridinol

potassium hydroxide

p-nitrobenzenediazonium tetrafluoroborate

→

title compound

Rendimiento 33.7%

5-Hydroxy-3-bromo-2-(4-nitrophenylazo)pyridine

Rendimiento 33.7%

Disolventes

water

acetic acid

Condiciones de reacción

Tratamiento posterior

1. 1
   workup.ADDITION1979 p 1572-1573) (11.845 g, 0.5 mol) was added
2. 2
   Filtraciónfiltered
3. 3
   Otroto dry in air
4. 4
   Otrowas chromatographed (silica gel; CHCl3/MeOH, 95:5 to 90:10)

Procedimiento

5-bromo-3-pyridinol (8.7 g, 0.05 mol) and potassium hydroxide (Fisher Scientific) were dissolved in water (200 ml). A suspension of p-nitrobenzenediazonium tetrafluoroborate (J. Org. Chem., Vol. 44, No 9. 1979 p 1572-1573) (11.845 g, 0.5 mol) was added, and the mixture was stirred for 1 hour, diluted with acetic acid (50 ml) and filtered. The crude product was allowed to dry in air, then was chromatographed (silica gel; CHCl3/MeOH, 95:5 to 90:10) provided 5.45g (33.7 %) of the title compound. MS (CI/NH3) m/e 323/325 (M+H)+. 1H NMR (DMSO-d6, 300 MHz) δ8.48-8.43 (m, 2H), 8.21-8.20 (d, J=2.37 Hz, 1H) 8.09-8.06 (m, 2H), 7.72-7.71 (d, J=2.37 Hz, 1H).

Fuente