Reaktion #810697

Reaktionsgleichung

sodium hydride

2-amino-6-methyl-pyridin-3-ol

6-methyl-2-nitro-pyridin-3-ol

methyl chloroacetate

→

6-Methyl-4H-pyrido[3,2-b][1,4]oxazin-3-one

Lösungsmittel

dimethylsulphoxide

Reaktionsbedingungen

Aufarbeitung

1. 1
   SonstigeThe reaction mixture was quenched with saturated aqueous ammonium chloride solution (10 mL)
2. 2
   Sonstigepartitioned between dichloromethane and water
3. 3
   SonstigeThe organic extracts were dried
4. 4
   Sonstigeevaporated
5. 5
   Sonstigethe residue was chromatographed
6. 6
   Wascheneluting with 0-20% ethyl acetate in dichloromethane affording the product as a white crystalline solid (4.7 g, 62%)

Vorschrift

A solution of 2-amino-6-methyl-pyridin-3-ol (5.7 g, 46 mmol) (prepared by reduction of 6-methyl-2-nitro-pyridin-3-ol according to the procedure of J. Kaminski et al, [J. Med. Chem, 30 (11), 2031 (1987)1 in dimethylsulphoxide (60 ml) was treated with sodium hydride (44 mmol) under argon. After 0.25 hours methyl chloroacetate (4 mL, 5 g, 46 mmol) was added and the mixture heated at 100° C. for 3.5 hours. The reaction mixture was quenched with saturated aqueous ammonium chloride solution (10 mL), then partitioned between dichloromethane and water. The organic extracts were dried and evaporated and the residue was chromatographed eluting with 0-20% ethyl acetate in dichloromethane affording the product as a white crystalline solid (4.7 g, 62%).

Quelle