Hydrochloric Acid → 7-METHOXY-QUINOXALIN-5-YLAMINE

A solution of 4-methoxy-2,6-dinitro-phenylamine (5 g, 23.5 mmol) in EtOH (200 mL) was hydrogenated over 10% Pd/C (2 g) at 40 psi for 1 hour. After H2 uptake had ceased, the reaction was filtered through a pad of celite and washed with EtOAc (50 mL) and concentrated. Glyoxal (8 ml, 704 mmol) and EtOH (50 mL) were immediately added and the reaction was heated at reflux for 2 hours. The cooled reaction was diluted with H2O (50 mL) and extracted into CH2Cl2 (3×100 mL). The organic phases were combined, dried over Na2SO4, filtered and concentrated. The resulting oil was purified by column chromatography (10% MeOH/CH2Cl2) affording 430 mg (10%) as a red oil. An analytical sample was prepared as the HCl salt from EtOAc affording a red solid.

1. filtrationthe reaction was filtered through a pad of celite
2. washwashed with EtOAc (50 mL)
3. concentrationconcentrated
4. temperaturethe reaction was heated
5. temperatureat reflux for 2 hours
6. customThe cooled reaction
7. extractionextracted into CH2Cl2 (3×100 mL)
8. dry with materialdried over Na2SO4
9. filtrationfiltered
10. concentrationconcentrated
11. customThe resulting oil was purified by column chromatography (10% MeOH/CH2Cl2)
12. customaffording 430 mg (10%) as a red oil

ORD record

ord-5914a2c300ef4033ae31b003234e2a21

Source dataset

uspto-grants-2001_11

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US06313126B1