Réaction #79059

Équation de réaction

Na2CO3

7-amino-4-oxo-3H-pyrido[4,3-d]pyrimidine

NaNO2

HBF4

→

7-fluoro-4-oxo-3H-pyrido[4,3-d]pyrimidine

Rendement 47.0%

Conditions de réaction

Traitement

1. 1
   Températurecooled
2. 2
   Extractionextracted with EtOAc (4×100 mL) The extract
3. 3
   Lavageis washed with water
4. 4
   Filtrationfiltered through silica gel (EtOAc)

Mode opératoire

A solution of 7-amino-4-oxo-3H-pyrido[4,3-d]pyrimidine (1.00 g, 6.17 mmol) in 60% HBF4 (25 mL) at 0° C. is treated with solid NaNO2 (0.85 g, 12.3 mmol, added in portions over 2 h), and is then stirred at 0° C. for a further 1 h and at 20° C. for 30 min. The resulting mixture is ice-cooled, neutralized with saturated aqueous Na2CO3, and extracted with EtOAc (4×100 mL) The extract is washed with water, then filtered through silica gel (EtOAc) to give 7-fluoro-4-oxo-3H-pyrido[4,3-d]pyrimidine (0.48 g, 47%) as a cream solid. 1H NMR (DMSO) δ 12.69 (1H, brs), 9.01 (1H, s), 8.31 (1H, s), 7.34 (1H, s)

Source