Reaction #71387

Reaction equation

8-(3,5-dimethoxy-phenyl)-2-hydroxy-quinoxaline-5-carbonitrile

POCl3

→

title compound

2-Chloro-8-(3,5-dimethoxy-phenyl)-quinoxaline-5-carbonitrile

Conditions

Workup

1. 1
   Temperatureto cool to rt
2. 2
   Concentrationconcentrated
3. 3
   workup.ADDITIONThe residue was diluted with DCM/NaHCO3 saturated aqueous solution
4. 4
   Extractionextracted with DCM
5. 5
   WashThe organic phase was washed with H2O and brine
6. 6
   Dryingdried (Na2SO4)
7. 7
   Filtrationfiltered
8. 8
   Concentrationconcentrated
9. 9
   OtherThe crude product was purified by silica gel column chromatography (Hex/EtOAc, 7:3)

Procedure

A mixture of 8-(3,5-dimethoxy-phenyl)-2-hydroxy-quinoxaline-5-carbonitrile (Step 85.5) (100 mg, 0.33 mmol) and POCl3 (1 mL) was stirred at 120° C. for 3 h, allowed to cool to rt and concentrated. The residue was diluted with DCM/NaHCO3 saturated aqueous solution and extracted with DCM. The organic phase was washed with H2O and brine, dried (Na2SO4), filtered and concentrated. The crude product was purified by silica gel column chromatography (Hex/EtOAc, 7:3) to afford 90 mg of the title compound as a yellow solid: ES-MS: 326.1 [M+H]+; tR=5.02 min (System 1); Rf=0.34 (Hex/EtOAc, 7:3).

Source